Introduction to Psychological Science: Integrating Behavioral, Neuroscience and Evolutionary Perspectives - William J. Ray 2021

Motivation and Emotion

LEARNING OBJECTIVES

✵ 10.1 Discuss the processes that influence how people are motivated.

✵ 10.2 Summarize the mechanisms that affect our levels of hunger and our eating behavior.

✵ 10.3 Explain the factors that affect our sexual motivation and behavior.

✵ 10.4 Discuss the scientific understanding of emotionality.

✵ 10.5 Discuss the major theories of emotion.

Imagine that as you walk across campus, a person of the opposite sex walks up to you and says, “I have been noticing you around campus. I find you to be very attractive.” She or he then says to you, “Would you go out with me tonight?” What would you do? If you were similar to the students who actually participated in this study, about half of you would say “yes,” which also means that about half of you would say “no.”

Would it matter if you were a male or a female? No, men and women both equally agreed to (or turned down) the request for a date.

Now, what if the person who found you attractive asked you to come over to their apartment that night?

Would you agree? What if they directly asked you to go to bed with them that night? What would be your response then?

Would you expect males and females to answer these last two propositions differently?

The answer is, of course, yes. In two original studies, about 70 percent of the males agreed to either go to the female’s apartment or to go to bed with her (Clark & Hatfield, 1989). No female, on the other hand, agreed to go to bed with the male who told her she was attractive. A few women (6% in one study and 0% in the other) agreed to go to his apartment that night.

We all have needs, but how we experience and express them is an important question for psychologists. This chapter focuses on basic motivations and emotions as well as factors that influence how individuals and groups differ in their expression.

Motivation

All of us come into the world with needs. We need food, water, and oxygen to create energy and live life. We need stimulation to help our nervous systems develop. Part of being human is to experience these needs. Swimming under water will at some point compel us to seek air. We also feel hungry and thirsty. Such needs are very basic. Some of these experiences follow a predictive pattern, such as feeling sleepy every night or hungry after not eating. These processes are built into us as humans and other multi-cell organisms. In fact, we even come into the world with preferences. Three-day-old babies show preferences for certain flavors (Mennella & Beauchamp, 1998).

Darwin initially spoke of two basic needs that motivate all organisms. These are self-preservation and sexuality. The common term used at that time was instinct. For Darwin, an instinct was a set of behaviors that was present in the organism and did not need to be learned (Darwin, 1859). In his Principles of Psychology, William James used a similar definition of instinct as “the faculty of acting in such a way as to produce certain ends, without foresight of the ends, and without previous education in the performance” (James, 1890: Chapter 24: 1,004). James further suggested that every instinct is an impulse. As such, instincts were critical processes that were part of the organism, which involved internal processes that can lead to action.

The subjective experience of a need is a stirring or desire to move. Actually, this is the Latin etymology of the English word motivation as well as of the English word emotion. Thus, motivations and emotions are processes that cause us to move and potentially engage in an action. Psychology has traditionally conceptualized motivation in terms of needs and drives, although these terms are rarely used today. Today, motivation is defined as the process that makes a person move toward a goal-directed behavior. Emotion is defined as a subjective or internal experience that is accompanied by physiological changes. Psychologists focus more on the mechanisms that create the states traditionally referred to as needs and drives as well as the underlying states accompanied with emotions.

One characteristic of needs or drives is that there is a goal state that is sought. We can think of experiences such as being hungry as having the goal of finding food. We can also describe the subjective experience of feeling satisfied after eating. On a physiological level we can consider the changes that take place in the gastrointestinal system and the brain structures that interact. One term used to describe this process is homeostasis.

Homeostasis was initially described by the French physiologist Claude Bernard. The term comes from the Greek meaning same and steady. The concept was further expanded by the Harvard physiologist Walter Cannon in his 1930s book The Wisdom of the Body. The basic idea is that a number of systems in our body seek to maintain the body’s stability. If our body becomes too hot, we begin to sweat to decrease our body’s temperature. Likewise, if we become cold, we shiver in order to increase our body’s heat. In this way homeostasis works like a thermostat in your house that keeps the temperature at a certain level. Besides temperature, hunger can also be seen as a homeostatic process in that when we feel hungry, we eat to create energy and return to a normal state. Overall, our search for a certain level of energy can be seen as homeostatic.

Basic Motivations

The humanistic psychologist Abraham Maslow (1908—1970) suggested that beyond basic needs humans also have the need to be recognized by others as well as to acknowledge their own self. Maslow referred to the desire to express one’s self in the context of humanity as self-actualization. However, he suggested that self-actualization would only come after basic needs were satisfied. For Abraham Maslow, these different needs can be organized in the form of a hierarchy.

This hierarchy is often portrayed as a pyramid (see Figure 10-1). The pyramid describes five basic sets of needs.

1. Physiological needs such as hunger, thirst, sleep, breathing, and sexuality.

2. Safety needs, which include the need for security, stability, protection, and order.

3. Belongingness and love needs, which include the desire to be part of a family or group.

4. Esteem needs, which include the desire for achievement, mastery, competence, and independence. Maslow also describes a subset of esteem needs, which include the desire for reputation, prestige, status, and appreciation.

5. The need for self-actualization represents a person’s desire for self-fulfillment.

Figure 10-1 Maslow’s hierarchy of needs.

The base of the pyramid is composed of physiological needs such as hunger and thirst. One basic idea is that the needs portrayed at the bottom of the pyramid must be satisfied before a person will seek higher needs. If you’re hungry, you will eat before you look for someone to become friends with. Likewise, you don’t seek status if you feel unsafe in your environment.

In describing the basic physiological needs, Maslow (1970) echoes Walter Cannon by emphasizing the role of homeostasis and the manner in which these needs reflect the wisdom of the body. This suggests that the physiological needs of a human are in constant flux and vary around a number of physiological parameters such as oxygen or blood sugar level. There are also a variety of unconscious mechanisms that motivate individuals in particular directions. For example, various studies have shown that children with nutritional deficits will seek foods that will correct these deficits. It is the physiological needs that are emphasized in the first part of the chapter.

Intrinsic and Extrinsic Motivation

Maslow initially developed his theory of needs in reaction to the strong learning through reinforcement view of human behavior. This view, as described by B. F. Skinner and others, suggested that humans do what they do to receive reinforcements with little emphasis on internal thoughts or feelings. Today, we know that ideas themselves can influence and direct our behavior. One focus in the history of motivation research in psychology was an emphasis on external factors. In our own lives there are numerous examples of external rewards. We study to make good grades, we work for money, and we sometimes do things to obtain praise from others. To perform behaviors for the seeking of rewards is referred to as extrinsic motivation.

Maslow suggested that there was more to life than just seeking rewards. We perform behaviors because we enjoy it. We play video games, listen to music, read books, or exercise for the experience itself. This is referred to as intrinsic motivation. Clearly, Maslow was using the concept of intrinsic motivation when he described self-actualized individuals. These are people who need to write or play music, create literature or science, or perform physical feats to be who they are.

The concepts of intrinsic and extrinsic motivation are person and situation specific. That is, you can see one individual displaying extrinsic motivation when they study for an exam while another person may genuinely love the material and want to learn everything they can. Given different material, you could see the opposite situation for these same two people.

CONCEPT CHECK

1. How does having a need or drive lead to motivation?

2. What is the meaning of homeostasis? What role does it play in our functioning as humans?

3. What are the five levels of Maslow’s hierarchy of needs? Give an example of each.

4. What is the difference between extrinsic and intrinsic motivation? Give an example of each.

Motivation for Food

Food plays an important role in the life of humans. On a basic level, we need food to supply energy to support our daily functioning. Unlike our need for oxygen, which must be satisfied in the moment, we are able to store the components of food for later use. The desire for food can be seen on a number of levels going from culture to genes.

Food also plays an important role in our social and cultural life. For example, food plays a critical role during the celebration of holidays such as Thanksgiving. Religious holidays also give food a critical role. In our everyday life, there are television channels dedicated to preparing and cooking food as well as eating foods from around the world. On an individual level, many of us look for “comfort foods” to change our feeling states. Likewise, there are also a number of individuals who eat when they experience stress, although some people eat less when stressed (Dallman, 2009). However, both those who eat more and those who eat less during stress increase the amount of comfort foods such as chocolate and sweets they eat. Further, feeling sad favors eating foods that are high in fat and sweetness.

Everyone has certain foods that they love and foods that they don’t like. Some of our choices are cultural and related to the foods that we grew up with. Some of our choices are genetic, such as the ability to drink milk into adulthood described previously. At times our evolutionary history may have us seeking substances that do not lead to a healthy lifestyle. For example, in our early history, sugar was not easy to come by. It was only found in foods that were not constantly available, such as fruits.

Since sugar gives us a pleasant feeling, we came to seek it. In fact, we consume sugars even when full. We think of drugs as being highly reinforcing for humans and other animals. However, one study showed that rodents are more likely to work for sweet rewards, even when not hungry, than to work for cocaine (Lenoir, Serre, Cantin, & Ahmed, 2007). The constant availability of sugars and other such substances today plays a critical role in obesity and some eating disorders, although other factors also play a role (Drewnowski, 1997).

What foods do you crave and when do you crave them? In terms of particular foods, chocolate is one of the most heavily craved foods. Why is this so? At this point it appears to be more than its physiological effects including the effects of sugar. These other factors also include aroma, caloric content, and texture. Further, the craving of chocolate is seen to be stronger in those who engage in binge eating than in those who do not (Wolf et al., 2017).

Feeling hungry and feeling full is also a homeostatic system that balances the intake of calories and their expenditure to perform the functions of our body. This is a complex system that monitors energy available and that involves both our gastrointestinal (GI) system and the brain. In fact, our brain is a major component of metabolism that is involved in the creation of energy. Over the past three decades, research involving appetite regulation has identified numerous hormones that influence feeling hungry and feeling full (Sandoval, Cota, & Seeley, 2008; Kaviani & Cooper, 2017). It is also these mechanisms that keep our weight fairly stable.

Experiences of Hunger and Satiety

Our experience around food ranges from feeling hungry to feeling full. Most of us have felt hungry between meals and gone looking for a snack. What are the mechanisms that underlie these experiences? Although the mechanisms that relate to food intake and metabolism are complicated in terms of the brain, the hypothalamus has been shown to play an important role (De Araujo, Schatzker, & Small, 2020; Koch & Horvath, 2014). Further, the hypothalamus can adapt quickly to changes in the environment in terms of particular hormones.

It is the hypothalamus that monitors the body’s energy supplies (Dietrich & Horvath, 2013). One of the ways it does this is to detect how much long-term energy is stored in fat. This is accomplished by detecting levels of the hormone leptin, which is secreted by fat and produced by a certain gene. With increased fat levels, more leptin is produced and can be monitored by the brain. In this way leptin reduces appetite and stimulates energy usage. Leptin is also seen to reduce the experience of reward associated with eating (Monteleone & Maj, 2013). If an individual lacks the gene that produces leptin, he or she will become obese. However, most people who are obese do not lack this gene.

Neurons in the hypothalamus are also sensitive to the body’s level of blood glucose. Because the brain needs energy, it is not surprising that there are neurons in the hypothalamus that are very sensitive to blood glucose levels. Specifically, there is a small area of the hypothalamus referred to as the arcuate nucleus that accomplishes the regulation of energy balance (Dietrich & Horvath, 2013).

The hypothalamus in terms of eating is often seen to work in a homeostatic manner. As described previously, homeostasis is the process by which the body keeps itself in balance. Like a thermostat that turns on heat when the air is cold and turns off heat when the air is warm, neurons in the hypothalamus are able to stimulate the appetite when energy levels are low. In one part of the hypothalamus, there are two different sets of neurons. One set stimulates food consumption, and the other set of neurons inhibits food intake.

Motivation for eating takes place on number of levels, including craving food, paying attention to food, and increased experiencing of foods. This is illustrated by the situation in which you go to the grocery store hungry and buy more food than normal (de-Magistris & Gracia, 2017). Neurons in the hypothalamus also perform the opposite function when you do not need food. That is, when you’ve had your snack, the hypothalamus sends out messages that make you feel less hungry. Specifically, eating a snack that results in an increase in leptin and glucose levels in your blood will reduce your desire to eat more food.

Eating a snack with another form of sugar, fructose, will actually increase your desire to eat (Lane & Cha, 2009). Eating foods with a fructose component, as compared to a glucose component, shows a smaller increase in the hormones that signal the experience of feeling full, or satiety. In one brain-imaging study, individuals were given drinks with either fructose or glucose (Page et al., 2013). The results showed that glucose, but not fructose, influenced the brain regions associated with appetite regulation and reward processing. Since fructose is often added to soft drinks, this can result in increased intake and obesity.

Figure 10-2 Location of hypothalamus and other structures in the brain.

Overall, researchers suggest there are three pillars for understanding how the brain controls appetite (Sternson & Eiselt, 2017).

1. The first pillar is neurons in the hypothalamus that, when activated, make us feel hungry. These are referred to as AGRP (agouti-related protein) neurons in that they produce a protein that acts to increase appetite. The activity of these neurons is more involved with food seeking rather than its consumption.

2. The second pillar is circuits of neurons involving the lateral hypothalamus. These circuits are related to the consumption of food and the positive effects of eating.

3. The third pillar is neurons in the hypothalamus that suppress eating when activated. They produce a protein referred to as CGRP (calcitonin gene-related peptide).

Thus, in separate parts of the hypothalamus are neurons whose activity make us seek food, feel good from eating food, and feel full, which is related to a cessation of eating. It is assumed that the circuits interact to maintain a homeostatic pattern.

Hormones in the Gastrointestinal System

After we eat food, hormones are released in the gastrointestinal system. These hormones signal a number of factors including the nature of the foods eaten. For examples, diets low in proteins increase food intake, whereas diets high in proteins decrease food intake. These hormones in turn go to our brain, especially the hypothalamus. One of these hormones is ghrelin. Ghrelin is produced by cells in the stomach that stimulate your appetite as well as promote gastric emptying. Another hormone as noted previously that reduces the desire to eat is leptin, which is released from fat cells.

Eating Pattern and Obesity

Motivation for eating has a longer-term evolutionary history. Over evolutionary time, there were environmental demands in which we needed to expend energy quickly and others in which little energy was required. One way our bodies do this is by reducing our metabolism when we eat less food. We also have mechanisms to store fat when foods are plentiful. In fact, all animals, including humans, tend to favor the intake of foods and fat storage in comparison to using available energy resources. This was reasonable since in our long past there were periods of famine. Although useful in highly unpredictable times, today with freely available foods in the developed world, there can be a mismatch between our evolutionary history and our current demands. For many people, a sedentary lifestyle is the norm. As such, these mechanisms make the balance of energy storage in the form of fat from eating and energy expenditure a difficult one for many people today. In fact, since 1980, the prevalence of obesity has doubled in more than 70 countries (The GBD 2015 Obesity Collaborators, 2017).

It is not only the amount of food eaten that is important but also the types of foods that one eats. One study showed that eating fruits, vegetables, and legumes reduced disease and death (Miller et al., 2017). This study examined 135,335 individuals aged 35 to 70 in 18 countries around the world. From a review of a number of studies, it is possible to make recommendations in terms of foods that one eats (Willett & Stampfer, 2013).

Good data now support the benefits of diets that are rich in plant sources of fats and protein, fish, nuts, whole grains, and fruits and vegetables. It is also suggested that you eat red meat in moderation and that you avoid excess sugar and processed foods, which often contain excessive sugars and salt. Many fad diets have not been shown to have exceptional health benefits. Also, the Centers for Disease Control and Prevention (CDC) has a number of resources to help individuals eat well (https://www.cdc.gov/nccdphp/dnpao/features/nutrition-month/ and https://www.cdc.gov/healthyweight/healthy_eating/index.html). Likewise, the US Department of Health and Human Services has a series of dietary guidelines for healthy eating (http://health.gov/dietaryguidelines/). In spite of this, Americans consume more calories than many other places in the world. Daily calorie intake for various countries in the world is shown in Figure 10-3.

Figure 10-3 Daily calorie intake worldwide.

Gender Differences in Weight

The effects of food intake influences body changes differently in males and females (Berthoud & Morrison, 2008). One major difference is where in the body excess food deposits fat (Blaak, 2001). In females, fat tends to be deposited in the hips and thigh regions. Excessive fat deposits result in a pear shape in females. Males, on the other hand, tend to store fat around the abdominal area. This results in more of an apple shape or “beer belly.” Also, as seen in Figure 10-4, women have more overall body fat than men, even when they are not over-weight. From an evolutionary perspective, this would be adaptive for females as they require a greater access to nutrition during reproductive experiences (Power & Schulkin, 2007). Levels of body fat are lower in athletes and higher in obese individuals (see Table 10-1).

Figure 10-4 Percentage of body fat for males and females by age.

Body Mass Index (BMI)

Weight and weight gain have become common topics in the popular press, including a large number of books on dieting. Part of this is an estimation of whether you are underweight or overweight. A common measure of weight in relation to obesity is body mass index or BMI. This is an indirect measure of body fat based on a person’s height and weight (see Figure 10-5). There are a variety of BMI calculators on the web as well as cell phone apps.

Figure 10-5 BMI is determined by comparing height and weight.

In general, a BMI score below 18.5 is considered underweight; 18.5—24.9 is considered normal; 25—29.9 is considered overweight; and 30 and above obese. A BMI greater than 30 is associated with increased mortality from cardiovascular diseases, diabetes, cancer, and other diseases. Further, weight gain in adulthood was associated with increased risk of developing chronic diseases in later life (Zheng et al., 2017).

CDC data suggest that 33.9% of Americans over the age of 20 are obese and 34.4% are overweight (http://www.cdc.gov/nchs/fastats/overwt.htm). There is a difference in these statistics by state. All states show an increase in obesity over the past 20 years. There has also been an increase in obesity for both adolescent boys and girls in the latest data over 20 years.

According to the CDC, overweight and obese individuals are at higher risk for the following disorders:

✵ Hypertension

✵ Dyslipidemia (for example, high low-density lipoprotein (LDL) cholesterol, low high-density lipoprotein (HDL) cholesterol, or high levels of triglycerides)

✵ Type 2 diabetes

✵ Coronary heart disease

✵ Stroke

✵ Gallbladder disease

✵ Osteoarthritis

✵ Sleep apnea and respiratory problems

✵ Some cancers (endometrial, breast, and colon)

In addition to an individual’s actual weight, there is also the person’s attitude toward their weight. In some cultures, being heavier in weight is seen as positive, whereas in others, it is thinness that is sought. Currently, in the US as shown by the popular press including books, dieting is a topic of great interest. However, there are times in which attitudes and behaviors related to eating go to the extreme. These situations may involve eating disorders.

Eating Disorders

The three major eating disorders are anorexia nervosa, bulimia nervosa, and binge-eating disorder (Brownley et al., 2016; Keel, Brown, Holland, & Bodell, 2012). Anorexia nervosa and bulimia nervosa are the most commonly discussed eating disorders. They tend to have an onset before puberty and mainly influence women. However, the issue of eating disorders in men is beginning to gain more attention, especially in such situations as male athletes attempting to achieve a certain weight to participate in a sporting event.

Anorexia Nervosa

Since the 1600s, anorexia nervosa has been described in terms of three characteristics. These are:

1. Food refusal

2. Onset in adolescence

3. Lack of concern of the consequences of not eating

There is a consistency in the way individuals with anorexia nervosa display the symptoms. These include a preoccupation with food while at the same time showing a resistance to eating. Body image is also distorted. That is, in addition to the outward signs of anorexia nervosa, there are also distortions in body image (Gaudio & Quattrocchi, 2012; McLean & Paxton, 2019).

One common characteristic is for the person to see both specific body parts and overall weight as being heavier than they are. The body image distortion has been described as having a perceptual, an emotional, and a cognitive component. The perception consists of whether one’s self or others are underweight, normal, or overweight. The emotional, or affective, component involves whether the person is satisfied or dissatisfied with one’s own body. The cognitive component consists of beliefs concerning one’s body image as well as the mental representation of one’s body. These beliefs exist separately without actually viewing body types.

Both cultural and biological factors play an important role. Twin studies suggest that 50% to 80% of the variance in both anorexia nervosa and bulimia can be accounted for by genetics. Overall, these genetic influences appear to show heritability of global attitudes toward food and dieting including the restriction of eating, binge eating, and self-induced vomiting. Genetic influences may keep those with anorexia nervosa from experiencing normal feelings of hunger (Couzin-Frankel, 2020; Zeltser, 2018).

In terms of cultural factors, anorexia is seen more in developed economies. Paradoxically, anorexia nervosa is higher in cultures where food is abundant. As a country develops, there is an increase in the occurrence of anorexia. It has been suggested that with economic development come changing roles for women, a shift in eating patterns, and an emphasis on thinness (Nasser, Katzman, & Gordon, 2001).

Bulimia Nervosa

Although overeating followed by purging has been described since Roman times 2,000 years ago, the eating disorder bulimia nervosa was not introduced into the medical literature until 1979 (Russell, 1979). The main characteristics are periods of overeating, in which the person feels out of control, followed by purging. This disorder is generally reported in women and associated with an over concern related to weight and appearance.

Overall, there are three major aspects of bulimia. The first is binge eating in which the person consumes large amounts of food. Typically, the individual consumes 2,000 calories in one sitting, which is equal to the number of calories recommended for a female’s daily intake for a healthy lifestyle. The second aspect is the purging. Purging is where a person eliminates food from the body by such means as vomiting, taking laxatives, diuretics, or enemas. The third aspect is a psychological one in which one’s self-worth is seen in relation to one’s weight or body shape.

Binge-Eating Disorder

Binge-eating disorder is characterized by the consumption of large amounts of food and the sense that one cannot control her eating behavior. Although the amount of food varies from person to person, it can go as high as 10,000 calories. Binge-eating is higher in those who are overweight than those who are normal weight. The prevalence is 2.9% in overweight individuals and 1.5% in normal weight individuals. Also, obese individuals take in a larger number of calories during binge eating and non-binge eating episodes. There is evidence to suggest that binge eating runs in families and is not related to obesity per se. Thus, it should be considered to be different from familial obesity. In terms of all eating disorders, it is a myth that eating disorders are only seen in females, as described in the box: Myths and Misconceptions: Eating Problems Are Only Seen in Females.

Myths and Misconceptions: Eating Problems Are Only Seen in Females

For many people when they hear about eating disorders, the image that comes to mind is that of a female. It may be a female who is underweight or someone we know who binges and purges. Although it is true that more females than males report eating disorders, it is not true that males do not also show any of these disorders. In fact, in cases of severe anorexia nervosa, both males and females show similar rates of death.

One review of the literature suggests that eating disorders in males are under-recognized and under-reported (Raevuori, Keski-Rahkonen, & Hoek, 2014). Health care professionals are also beginning to recognize that males differ from females in how they display problems in eating. For example, issues with eating may also occur with issues with exercise and being muscular in men. That is, males may engage in extreme exercise at the same time they engage in problematic eating. Also, certain groups such as gay males show problems in eating patterns and exercise.

Another area in which male eating disorders are seen is that of sports. It may be surprising that eating disorders have been found to be more common among elite athletes than among the general population (Sundgot-Borgen & Tortstviet, 2004). Eating disorders are seen in both male and female athletes, although they are more common for females than males. For men, the most common disorder was bulimia, found especially in the weight category sports such as wrestling (9%). In sports such as wrestling, an athlete must “make weight.” That is, to compete in a certain weight category, the individuals must show their weight to be at certain level. For some, this puts pressure on them as they consider ways to make their required weights. One way to do this follows the purging pattern seen in bulimia.

Student athletes are influenced by a number of individuals, including their coach. In one case study of a 12-year-old runner, his coach suggested he might do better competing in a different track and field event such as shot put (Dosil, 2008). Since this student had wanted to be a lean runner as he had seen on TV, he became upset at this advice. Rather than discuss it, he went home and said to himself that he should stop eating so he could become lean. This upset his parents as he refused to eat and began to lose weight. Fortunately, in this case a psychologist was able to work with the adolescent, his parents, and his coach to reduce the problematic eating behaviors.

Another case involved a 22-year-old taekwondo national champion competing to go to the Olympics (Dosil, 2008). He was at a higher weight level than he liked and argued with his coach about his weight. The coach thought the athlete was letting himself go and putting on weight. With the competition coming soon, he considered a number of ways to lose weight and be allowed to compete in a lower weight-class category. These included taking laxatives and diuretics, going to a sauna, and training in plastic clothing. Feeling the athlete was not working at his potential, the coach consulted a sports psychologist who was able to work with the athlete and his coach in terms of the advantages and disadvantages of remaining in the current weight class. This turned into a more long-term collaboration, which resulted in adequate food intake with the athlete performing well.

At this point health care workers and researchers are beginning to identify assessment techniques that identify males with eating problems as well as groups that may be at risk. This includes understanding how eating disorders differ in males and females.

Thought Question: What factors do you think are important in characterizing the differences in eating disorders in males and females?

CONCEPT CHECK

1. Food clearly represents a basic human need. What are some ways it goes beyond that basic level to become a motivation?

2. What are the three critical pieces in understanding how the brain, particularly the hypothalamus, controls appetite?

3. How does our evolutionary history in terms of eating pattern play a role in obesity today?

4. What are the three major eating disorders described in this chapter? What are the defining characteristics of each?

Sexuality

Sexuality is a driving force in many species including humans. The creation of offspring is different in different species. In some species such as frogs a single sexual encounter can produce a hundred offspring. In other species such as humans, sexuality generally leads to a single infant. Also, timing of sexual activity varies. Most primates only engage in sexual activity when there is a high probability of producing offspring. Humans, on the other hand, may engage in sexual activity at any time. In fact, the World Health Organization estimates that more than 100 million acts of sexual intercourse between humans take place each day. However, only 1 in a 100 will result in conception.

Humans use the internal experience of sexual arousal and the external experience of sexual activity for a variety of purposes (see LeVay & Baldwin, 2012, for an overview). Humans spend more time in the sex act itself than do other species. For example, unlike male chimpanzees who go from penile penetration to ejaculation in only 90 seconds, seven out of ten American adults questioned reported spending 15 minutes to 1 hour making love. Further, unlike many species, humans are one of the few species that has sex face to face. This suggests that sexual activity for humans goes beyond basic motivation and has an important pair bonding and social component.

Historical Perspectives

Humans have depicted sexual activities in paintings and carvings for thousands of years. Some of the more famous are Etruscan ceramic plates showing a variety of sexual positions dating from some 2,500 years ago in Italy. With the excavation of Pompeii and Herculaneum near Naples, Italy, a variety of scenes were discovered on the walls in the cities that graphically depicted sexual activities. These towns were covered by volcanic ash when Mount Vesuvius erupted in 79 AD. Similar sexual illustrations have been found throughout the world.

However, at certain times, some cultures have seen sexual activity as a negative force in human life. In the 18th and 19th centuries in Europe and the United States, there were those in the medical profession who suggested that sexual stimulation, especially masturbation, could lead to mental illness. In the late 1800s, John Kellogg was a physician who ran the Battle Creek Sanitarium in Michigan and crusaded against masturbation. Both graham crackers and unsweetened cornflakes were introduced as an aid for reducing sexual desire. His brother added sugar to the cornflakes and sold them through his Kellogg’s company.

Also in the 1800s, a number of scientists began to approach sexuality from a scientific perspective. Charles Darwin presented the manner in which sexual selection and self-preservation were important instincts seen across many species. Sigmund Freud emphasized the manner in which sexuality was an important driving force in humans. Havelock Ellis in England was one of the first to study human sexuality itself.

From 1897 to 1910, Ellis published a series of books entitled Studies in the Psychology of Sex. In these books he suggested variations in sexuality should be viewed statistically in terms of frequency. He also suggested that variations in sexual practices had their roots in normal sexual practices. Ellis also went against a common notion at that time and suggested that females like males have sexual desires and seek and enjoy sex. Further, he suggested that a gay or lesbian orientation was a normal variation of human sexuality and should not be viewed as a disorder. He also suggested that homosexual tendencies were present at birth.

In the 1930s, Alfred Kinsey, a zoologist, was asked to teach a course on marriage. In preparing for the course, Kinsey realized that little was known about the sexual behavior of Americans. Further, students found it difficult to obtain factual information free of moral or social perspectives. This led Kinsey to conduct a large-scale survey of some 12,000 individuals across the United States. The results of these surveys were published in two books: Sexual Behavior in the Human Male (1948) and Sexual Behavior in the Human Female (1953). In 1947, the Institute for Sex Research was established at Indiana University with Alfred Kinsey as director. This was later renamed the Kinsey Institute and continues performing research related to sexuality (https://kinseyinstitute.org/).

The original Kinsey survey focused on sexual experiences in terms of various socioeconomic variables such as age, education, marital status, occupation, and religious identification. The prevailing cultural myth of the middle of the last century was that females merely engaged in sex for procreative purposes or to please their male partners.

Many Americans in the 1950s were shocked to learn that females are as capable as males of sexual response. Further, 50% of the females interviewed had engaged in pre-marital coitus and 25% had engaged in extramarital sex. In addition, 84% of the males and 69% of the females reported being aroused by sexual fantasies. Also, 89% of the males and 64% of the females used fantasy as part of masturbation. Even more shocking to some was the number of males and females who reported they had masturbated (92% for males and 62% for females). Some newspapers and magazines refused to publish stories about this survey and its data. Some lawmakers even suggested it undermined the moral fiber of the nation.

Sexual Activities of Americans

In 2016 the Centers for Disease Control and Prevention (CDC) reported a survey that included face-to-face interviews with a national sample of 10,416 males and females in the US (https://www.cdc.gov/nchs/data/nhsr/nhsr088.pdf). In order to obtain more accurate information, the information in the survey that was related to sexuality was collected using a laptop computer instead of communicating it directly to the interviewer. As can be seen in Figure 10-6, among males and females 15—44 years of age, 92% of males and 94.2% of females have had vaginal intercourse. Further, 87.4% of males and 86.2% of females have had oral sex with a member of the opposite sex. Anal sex with the opposite sex was lower: 42.3% for males and 35.9% for females. In this survey, any reported same-sex contact was 6.2% for males and 17.4% for females. This included people who saw themselves as bisexual and homosexual/lesbian. This survey was updated from 2002 and 2011 surveys, which showed similar results.

Figure 10-6 Percentage of males and females 15—44 years of age who have had each type of sexual contact: United States, 2011—2013.

In 2010, the Center for Sexual Health Promotion at Indiana University’s School of Health, Physical Education and Recreation published a comprehensive study on sexual attitudes and behaviors (http://www.nationalsexstudy.indiana.edu/). The survey included description of more than 40 combinations of sexual acts that people perform during sexual events, the use of condoms, and the percentage of Americans participating in same-sex encounters. The survey gathered information from 5,865 adolescents and adults aged 14 to 94. This survey (see Table 10-2) shows that sexual activity continues across the lifespan and that there is a variety in the types of sexual acts that humans engage in. It should be noted that the CDC study asked if a person had performed a specific sexual act, whereas the Center for Sexual Health Promotion study asked if the sexual act had been performed in the last 12 months.

Understanding Human Sexuality

Like many human processes, sexual arousal and desire take place on a number of levels in a complex manner. There are cognitive considerations through which an individual may increase desire or choose to inhibit sexual activity. Thoughts, images, and other human cognitive processes can both increase and decrease desire. This level of functioning is only beginning to be understood in terms of sexual disorders. There are also emotional experiences contained within the sexual experience that may include joy and love. Finally, there is the physical level of functioning that includes the activities included in sexual encounters. Across all three levels, one important research question has been the manner in which measurements can be made.

With the advent of psychophysiological techniques to measure blood flow in the sexual organs of males and females, a different type of precision is possible. However, as with a number of psychophysiological measures, the relationship between changes in physiology and the experienced cognitions and feelings may not be exact. More recently, measures of brain activity using such brain-imaging techniques as EEG or fMRI allow for an understanding of cortical involvement. Sexual responding in a variety of species is related to specific external signals that are related to the possibility of conception. Humans, on the other hand, can also respond to internal thoughts and continued sexual arousal even without external stimuli.

In the popular press, men are often portrayed as thinking about sex much more often than women. However, clear research has not been available. In order to study the differences between men and women in cognitions, college students were asked to click a small counter every time they thought about sex, food, and sleep (Fisher, Moore, & Pittenger, 2012). These data show that men did indeed think more about sex than women. However, they also thought more about food and about sleep than women did. Statistical analyses did not show that males and females had different patterns of thought in relation to food, sex, and sleep. Thus, the gender differences relate to appetites in general rather than in a specific domain.

In studies of sexual orientation including heterosexual, homosexual, and bisexual individuals, it has been shown that these different groups are aroused by different types of stimuli. One study examined self-reported arousal in males as well as changes in penis size in relation to videos of explicit sexual interactions (Cerny & Janssen, 2011). Males who identified themselves as heterosexual, homosexual, or bisexual were asked to watch videos of males and females engaging in sex, males engaging in sex, and scenes including both males and females in a bisexual situation. As in previous research, heterosexual males showed the most changes in erections and self-report arousal to the heterosexual videos. They also showed the least changes to the homosexual videos. Both bisexual and homosexual men showed similar changes to the homosexual videos. However, the bisexual males showed the greatest changes to the bisexual videos. Overall, this research suggests that males show both subjective and physiological arousal in a manner that is consistent with their sexual orientation.

Brain Activity and Sexuality

Brain-imaging studies allow for cortical measures of arousal in addition to self-report and blood flow changes in sexual organs. Overall, when both males and females achieve orgasm, there are changes in the brain. In males, areas involved in vigilance shut down. When males experience an ejaculation, the same areas of the brain are active as when the person takes heroin. As seen using positron emission tomography (PET) these areas are the midbrain and the ventral tegmental area (VTA). In females, areas involved in controlling thoughts and emotions become silent (see Portner, 2008 for an overview).

Do men and women look at different aspects of a picture depicting sexual activity? One way to answer this question is to use eye tracking, which measures where a person looks when viewing stimuli in real time. One study suggests that both males and females look at the bodies of opposite sex nudes rather than the faces (Lykins et al., 2006). In another study, while viewing sexually explicit photographs of heterosexual couples engaged in intercourse or oral sex, males spent more time looking at the face of the female, whereas females spent more time looking at genitals (Rupp & Wallen, 2007). Females who were on birth control pills spent less time looking at the sexual characteristics of the picture.

Sexual Arousal

Since the term sexual arousal was introduced to the scientific literature in the 1930s, it has referred to a number of distinct processes (see Janssen, 2011; Sachs, 2007 for overviews). The term has been used in a psychological sense to refer to the internal experience of both cognitive and emotional processes. It has also been used in a physiological sense to refer to hormonal changes, brain changes, and changes in sexual organs related to blood flow. It is also the case that the subjective experience of arousal and genital physiological responses and arousal may not go together. In terms of gender differences, males show a higher correlation between genital responses and subjective sexual arousal than women (Chivers et al., 2010). This has led some researchers to suggest that females are more sensitive to the situational context in which sexual activity takes place than are males.

Sexual Functioning

In the 1960s, William Masters and Virginia Johnson began laboratory studies of the human sexual response by observing couples engaging in sexual activities. Although sexual activity had been studied in animals for at least 200 years, human laboratory studies were first reported in the 1960s. Before this time, little was known concerning what happens to our bodies as we become aroused and engage in sexual activity. In order to understand these processes, Masters and Johnson created instruments that were able to film and measure changes in male and female sexual responsiveness during arousal and sex. Masters and Johnson also studied clinical populations to help treat sexual and reproductive problems. Their major books include: Human Sexual Response (1966), Human Sexual Inadequacy (1970), and Homosexuality in Perspective (1979).

In studying the sexual responses of males and females, Masters and Johnson realized that there was a similarity in how men and women experienced the sexual experience (Masters & Johnson, 1966). They identified four phases of the human sexual response, which are (1) excitement, (2) plateau, (3) orgasm, and (4) resolution (see Figure 10-7). It should be noted that Masters and Johnson saw dividing the sexual experience into four parts as arbitrary and other researchers have used slightly different categories. Also, outside the laboratory, sexual activity begins with desire and this should be considered as an initial step preceding Masters and Johnson’s four phases (see Wincze & Carey, 2001 for an overview). The four phases of sexual response can be described on a variety of levels. The two main ones are blood flow, which is referred to as vasocongestion, and muscular tension, which is referred to as myotonia.

Figure 10-7 The human sexual response in terms of Masters and Johnson’s four stages. The letters A, B, and C show different patterns of sexual responses seen in the study. Pattern A in males and females shows an orgasm. Pattern B shows a pattern that does not lead to orgasm. Pattern C shows multiple orgasms.

In the excitement phase, blood flow is increased in the genital region in both males and females. This is both a physiological and a psychological state. In males, this results in an erection of the penis and the testes becoming elevated. In females, blood flow swells the clitoris and enlarges the labia. Also, the vagina begins to moisten. Excitement is felt throughout the body with increased muscle tension. Both the penis and the clitoris are richly endowed with nerve endings, which make them highly sensitive to touch, pressure, and temperature, which leads to the sensation of pleasure.

The experiences begun in the excitement phase continue during the second of Masters and Johnson’s phases, the plateau phase. During this phase, most individuals pay little attention to external stimuli as the pleasurable internal experiences continue. In the male, the Cowper’s gland releases a substance that changes the pH of the urethra from the acidity of urine to protect the sperm that will be released during orgasm. There is also an increase in heart rate and breathing. Some individuals also show a flush throughout their body.

The tension of the plateau stage climaxes in the third phase: orgasm. Muscular contractions in the male cause the sperm from the testes to be released, become part of the seminal fluid from the prostate, and be expelled. This experience lasts only a few seconds. In the process of ejaculation, the internal sphincter of the bladder closes in a manner that both prevents semen under pressure from entering the bladder and urine from the bladder from becoming part of the seminal fluid. In females, pelvic muscles also contract in a somewhat rhythmical manner, which may lead to the experience of a climax. Both men and women show muscular spasms throughout their bodies.

The fourth phase is the resolution phase following orgasm. Both males and females return to pre-arousal levels during the resolution phase. This includes a decrease in blood flow and muscle tension. During resolution, males, unlike females, experience a time period in which they cannot achieve another orgasm. This time period generally increases with age.

Gender and Sexuality

The beginning of this chapter asked you to imagine that as you walk across campus, a person of the opposite sex walks up to you and says, “I have been noticing you around campus. I find you to be very attractive.” She or he then offers you a number of alternatives. These range from going out on a date to having a sexual affair. Clearly, there could be individual differences for why one gave the answer he or she did. They could have been busy, not felt comfortable, responded in terms of a cultural or religious norm, and so forth. However, there were clear gender differences in our willingness to make ourselves available to another, especially for sexual activity. Why is this?

One answer is related to our human history. In thinking about sex differences from this perspective, we would expect to see the greatest differences in areas in which males and females have faced different adaptive problems. Conversely, with challenges that both males and females alike faced, we would expect to see fewer sex differences. The basic idea is that males and females have experienced different roles in reproduction and parenting throughout our long human history. In turn, males and females have faced different challenges, which have led to different processes in structure and function. This may have also led to different priorities in accomplishing these goals. In many ways scientists are just beginning this exploration and thus many important factors have yet to be articulated.

Let’s begin with the realization that the mechanisms of reproduction differ in males and females. In mammals, males produce small mobile sperm in large numbers, whereas females produce a relatively limited number of large eggs. One important pressure of the female is that she carries the fertilized egg to the birth of the offspring. The male, on the other hand, is not required to be temporally and spatially involved in the development of the fetus in the same way as the female. Thus, it is potentially possible for a given male to be involved in the production of many more offspring than a given female. Further, during both the time in which the female carries the fetus and after birth, the female must find resources such as food to supply the energy requirements of both herself and her offspring. Traditionally, the consequences of having a sexual relationship differ for a male and female in terms of pregnancy. Culturally, the burden of pregnancy has been on the female worldwide. Sexual practices have changed in the last 50 years with the advent of more successful forms of birth control.

The differences in terms of reproduction requirements between men and women have also led evolutionary psychologists to suggest jealousy would be expressed differently (Buss, Larsen, & Semmelroth, 1992; Buss, 2018). The basic idea is that since a male cannot know for certain who was the father of a child, this will lead to greater jealousy in relation to a female having sexual relations with another man. A female, on the other hand, desires that her mate be invested with her child and thus would show more jealously in terms of emotional infidelity. One review looking at 25 years of research in this area suggests support for the gender differences in jealousy, although a debate still exists (Edlund & Sagarin, 2017). It should also be noted that jealousy is not experienced in the same way with same-sex couples.

Other related answers to the gender differences can be seen in four major areas. These are sexual desire, commitment, aggression, and flexibility.

The first gender difference in sexuality is sexual desire. Overall, men show more interest in sex than do women, and this can be seen in a variety of ways. For example, males report thinking about sex more than females, including more sexual fantasies and feelings of desire. Males are also more interested in visual sexual stimuli. They like looking at sexually orientated magazines or Internet sites and are also more willing to spend money to obtain such stimuli. This is less true with females. Recent brain-imaging research has shown that males produce greater activation of the amygdala and hypothalamus than do females in response to viewing sexual stimuli, although both males and females showed similar responses in areas of the brain associated with reward, and both rated the material as equally arousing (Hamann, Herman, Nolan, & Wallen, 2004). In actual sexual behavior, there are also gender differences, with males seeking sex more often than females. This is also true with same-sex orientation, as seen in comparisons of gay and lesbian couples. That is, homosexual gay couples report having sex more often than lesbian couples. In one meta-analysis of 177 studies examining gender differences in a variety of sexual behaviors and attitudes, incidence of masturbation showed the largest difference (Oliver & Hyde, 1993). The gender differences found in sexual desire or behavior cannot be related to satisfaction of experience since this meta-analysis also found no differences in level of sexual satisfaction between males and females.

The second gender difference in sexuality is commitment. This is true for both attitudes and behavior. When asked about sexual desire, males are more likely to emphasize physical desire and intercourse, whereas females are more likely to describe relationship elements. Likewise in fantasies, females tend to include familiar partners and commitment, whereas males are more willing to include strangers and emphasize specific sexual acts. Males are also more willing to engage in premarital and extramarital sexual behaviors than females.

The third gender difference in sexuality relates to aggression and sexuality (see Campbell, 1999 for an overview). Human males have been shown to engage in aggression more often than human females from about age 2 onward. Such data as police records from across a variety of cultures universally show males to be more aggressive than females. Not only are males more aggressive, but they commit more serious crimes, including almost 90% of the murders reported in the United States. When asked to describe their own sexuality, males are more likely than females to include a dimension involving aggression, power, and dominance (Andersen, Cyranowski, & Espindle, 1999). Men are also seen as taking the lead in early stages of dating relationships, and although females do initiate sexual behaviors, they do so less frequently than their male partners (Impett & Peplau, 2003). Finally, using physical force to initiate sexual intercourse is primarily a male behavior (Felson, 2002).

The fourth gender difference in sexuality relates to the manner in which external factors can influence attitudes and behaviors (see Baumeister, 2000 for a review). The research suggests that males are less sensitive to situational factors than are females in terms of sexual behaviors. In reviewing this research, Baumeister (2000) describes three basic themes that emerge. One theme is that once a male’s sexual predispositions or tastes emerge, they will remain stable. Another theme is that a female’s predispositions will be more influenced by her culture and society than will a male’s. From this one would predict that females would vary from one culture to another in terms of sexual predispositions. The final theme is that the relationship between one’s attitudes toward sexuality and one’s behavior will be different for males and females. That is to say, females should show higher correlations between cultural attitudes and sexual behavior than males, whereas males should show higher correlations between their own sexual attitudes and behaviors.

CONCEPT CHECK

1. Sexuality clearly represents a basic human drive. What are some ways it goes beyond that basic level to become a motivation?

2. What are the unique contributions of the following people to our understanding of the historical perspectives of human sexuality:

a. John Kellogg?

b. Charles Darwin?

c. Sigmund Freud?

d. Havelock Ellis?

e. Alfred Kinsey?

3. What did the Centers for Disease Control and Prevention (CDC) survey in 2016 and the Center for Sexual Health Promotion at Indiana University’s School of Health, Physical Education and Recreation study in 2010 contribute to our understanding of the sexual activities of Americans?

4. What are the three levels on which human sexual arousal and desire take place?

5. Describe human sexual arousal from the following perspectives:

a. Physiological

b. Psychological

c. Subjective experience

d. Gender

6. What are the four phases of Masters and Johnson’s model of human sexual response? How is it different for males and females?

7. Research has shown clear gender differences in our willingness to make ourselves available to another, especially for sexual activity. What five explanations were presented as to why this might be so?

Emotion

William James published an article in 1884 with the title “What is an emotion?” More than 130 years later we still do not have a definitive answer to his question. As noted by many authors, emotionality is a difficult concept to define. Everyone seems to know what it is until asked. To complicate matters, everyday English does not clearly distinguish between feelings, moods, emotions, passions, affects, and motivations. Further, emotional experience and expression are related to your culture and situation (Barrett, Adolphs, Marsella, Martinez, & Pollak, 2019).

One neuroscientist, Antonio Damasio, suggests that emotions are our instinctual bodily reactions to specific situations such as seeing a bear in the woods (https://www.scientificamerican.com/article/feeling-our-emotions/). That is, when we see the bear, our heart races, our breathing changes, our mouth becomes dry, and our muscles prepare to run. Feelings, on the other hand, occur when we become aware of these bodily changes. As such, feelings can be influenced by our expectations and previous experiences. That is, if we believe that where we are walking is a dangerous place, then we may experience changes in our bodily processes in a stronger fashion. Likewise, we can experience the feelings a sick person is going through as we have memories of ourselves being sick.

We can also have mixed emotions at the same time (Russell, 2017). However, most of us are able to describe the emotions that we are experiencing and are able to distinguish between feeling states. An emotion is a positive or negative reaction that is in response to a particular behavior or physiological activity. Most psychologists see emotions as part of our human history as adaptations and communications. Mammal mothers, including humans, have a brain circuit that goes from the hypothalamus to the ventral tegmental area (VTA). This pleasure area in the brain shows an increase in the neurotransmitter oxytocin, which is associated with a feeling of caring (Asma & Gabriel, 2019). Emotions are not only expressed in our faces, but also in our voice and touch, as when we hug one another (Schirmer & Adolphs, 2017). Seeing a mother kiss her son in an MRI (magnetic resonance imaging) can help us to realize the universality of feelings. We experience the image without regards to culture, race, or socio-economic factors.

How to understand and define emotionality is a topic of current debate (see Adolphs, 2017; Adolphs & Anderson, 2018; Asma & Gabriel, 2019; Barrett, 2017; Keltner, Sauter, Tracy, & Cowen, 2019; Ortony & Turner, 1990; Russell, 2003). Carroll Izard asked more than 30 experts in the field of emotion research to give a definition of emotion. He found no consensus and some even said it was not possible to define the term emotion (Izard, 2007). However, current research suggests that emotional information is important and influences all of our decisions, including what we pay attention to, how we learn, as well as what we remember (Todd, Miskovic, Chikazoe, & Anderson, 2020).

Figure 10-8 This image shows a mother kissing her son. The image was created in a brain-imaging scanner and shows the brains of both the mother and son as well as the act of kissing. People from around the world experience this as a mother loving her son.

One debate centered on the number of specific emotions. Darwin suggested that a number of specific emotions were part of the patterned reaction of the organism to specific situations. He basically saw emotions as an action pattern. You see a bear and experience fear. These basic emotions include surprise, fear, disgust, sadness, anger, and fear. But he also considered what are called social emotions in that they are often seen in a social context. These include guilt, love, shame, and blushing. In the same way that we see a multitude of colors based on the processing of three types of receptors, our emotional processes can be based on a few primary ones. Other researchers have noted the close connection between motivational states and emotions, as would be seen in sexuality, play, helplessness, and anger, as well as caring and attachment (Panksepp, 1998, 2004, 2017).

Current research is seeking to combine the basic emotion approach of examining six or so emotions with social and motivational emotions to examine some 20 or 30 different states (Cowen & Keltner, 2017, 2020; Cowen, Sauter, Tracy, & Keltner, 2019). Most examples of emotional expression or experience are blends of different states. Some emotions such as sadness, anger, or fear show more cross-cultural consistency than others. Overall, current researchers not only note the manner in which emotions can be evoked in specific situations but are also influenced by expectations as well as one’s culture (Barrett, Lewis, & Haviland-Jones, 2016). Further, with the advent of digital media, we can share emotional experiences with a large number of people (Goldenberg & Gross, 2020).

Research examining how emotional terms in different languages are related to one another suggest that emotionality has both a cultural and universal basis (Jackson et al., 2019). That is, although happy is very different from fear or anxiety in most cultures, cultural factors can influence how happy or anxiety is related to which other emotional states. Individuals are also able to experience emotional differences from another’s voice cross-culturally (Laukka & Elfenbein, 2020). Further, physiological activation is an important aspect of understanding emotional terms.

Research suggests that our brain uses a range of pre-programed solutions for solving problems of daily living (Bach & Dayan, 2017). Emotions are a critical part of these programs. However, with humans in comparison to some other animals, the brain plays an active role in predicting what happens next and, in this way, emotional expression and regulation varies by situational factors as well as our expectations. Further, our sensory system plays an important role in how we create and experience emotional processes (Kryklywy, Ehlers, Anderson, & Todd, 2020). Thus, more sophisticated pattern analyses of neuroimaging data show that affective dimensions and emotion categories are uniquely represented in the activity of distributed neural systems that span cortical and subcortical regions (Kragel & LaBar, 2016).

What is troubling for some authors is that research has not found exact brain patterns that completely differentiate one specific emotion from another. However, it is clear that some parts of the brain and the networks connected with them are involved in different specific emotions (Gu et al., 2019). In specific, the amygdala has been associated with fear, the insula with disgust, the anterior cingulate cortex with sadness, and the orbitofrontal cortex with anger.

This part of the chapter will present a scientific understanding of emotionality. As a scientific topic, emotions have been studied from the standpoint of watching humans and other animals experience different states. Human facial expressions have been a large part of this approach. This was the classic approach of Darwin in the 1800s, which will be discussed in some detail. Emotions have also been studied from the standpoint of human experiences in terms of self-reports, often using rating scales. This approach was used by Wilhelm Wundt in the 1800s. For more than 100 years, the physiological responses such as changes in heart rate and electrodermal responses such as sweating have also been used. More recently, emotions have been studied in terms of brain networks and particular brain structures involved. From an early age, humans also learn to regulate their emotions (Tottenham, 2017).

Historically, emotionality has been studied in terms of specific emotions such as anger, fear, and happiness. As you will see, Darwin saw these emotional states as helping the person or animal to better function in his or her environment. Emotional states also function as a way in which we communicate important information with one another. Whereas Darwin sought to use emotionality to describe the sum of a set of experiences and reactions to the environment, Wundt (1912) sought to break down the emotional experience into its component parts. Wundt emphasized two properties. The first was valence, which ranged from feeling pleasant to unpleasant. The second property was arousal, which ranged from low to high arousal. Thus, any emotion could be described in terms of these two dimensions.

There has been considerable debate concerning these two approaches. That is, should we use a categorical approach of describing specific emotions such as anger, fear, or happiness or should we use a dimensional approach of noting where an emotional experience falls on the pleasantness/arousal dimensions. The answer appears to be both. It may be the case, as in many debates in science, that we discover that both positions are useful but under different conditions. For example, in science, ice and steam are categorical states. However, they can also be understood by their relation to an underlying dimension, that of temperature or the kinetic theory of heat to be specific. Likewise, our visual system transforms a continuous electromagnetic spectrum into discrete experiences. Receptors in our nervous system are tuned to three major frequencies that result in our experience of specific colors related to red, green, and blue. If our experience of emotionality is similar, this would suggest that it is quite possible to have both a dimensional approach and a categorical approach to emotionality.

We can further consider emotions as experiences created by our brain. Although we speak of emotions in the same way we speak of colors, different emotions like different colors may have evolved at different times in our human history. Öhman (1999), for example, has suggested that different emotions should be viewed as independent from one another in that they may have evolved at different times in our human history.

Darwin suggests that certain of our emotions such as joy or fear occurred early in our evolutionary history while others such as contempt or disdain would have come later. Darwin also speculates that early emotions such as disgust share the same facial expression as that seen in the motor action of vomiting. What could this mean? For Darwin it meant that emotional expressions such as disgust accompanied previous acts such as vomiting. Over evolutionary time, the expression of disgust came to be a response of its own. In this sense, our emotional expressions can be seen as coming from primitive motor processes and in this way represent the beginning of an action that is not completed. However, humans have developed means of regulating emotions and their expression. As such human emotional systems have rich interconnections with cognitive processes in the brain.

Different emotions also influence our bodies in different ways. If you make the facial expression of fear, for example, you will be able to view a larger part of the environment around you and find a particular object in your vision than if you experience disgust (Susskind et al. 2008). Disgust shows just the opposite pattern. Not showing emotions can also disrupt our relationships with others (Niedenthal & Brauer, 2012). Some expressions such as a smile can be used for different purposes. These different social functions are reinforcing desired behaviors in others, affiliation and maintaining social bonds, and reflecting social hierarchies and dominance (Martin, Rychlowska, Wood, & Niedenthal, 2017). However, each of these smiles use a different set of facial muscles.

From a human origins perspective, we want to ask the functional question of the role of emotionality in our human history. In doing this, we can break up the concept of emotion into emotional recognition, emotional production, and even the nature of emotions themselves. We can also describe the external aspects of emotions and consider the situations that bring forth particular emotional processing. Some films make us cry while others make us laugh. Of course, the emotion is not in the film but in us and in our interaction with the plot of the film. We can also consider the internal aspects of emotions and describe the internal recognition and experience of emotionality. Current research also suggests that our ability to quickly make trait characterizations of other people in social situations, such as their trustworthiness, may have evolved from our ability to analyze emotional expressions (Todorov, 2008).

Darwin and The Expression of Emotions

One critical scientist in the study of emotions is Charles Darwin. In The Expression of the Emotions in Man and Animals, Darwin portrays a careful observation of emotionality. Throughout his book, Darwin presents drawings and photographs of people and animals as they express different emotions. The common theme is that emotions are universal and represent an example of evolution through natural selection.

Paul Ekman (2009) suggests Darwin made a number of important contributions to our study of emotions.

1. Darwin saw emotions as discrete. That is to say we experience fear, anger, disgust and so forth as distinct entities.

2. Darwin emphasized the human face in the expression of emotions, as illustrated by the photographs of human faces he used in his book.

3. One of Darwin’s main ideas is that emotional processes are innate and found across a variety of species including humans. Darwin clarified this idea by suggesting that while facial expressions are universal, gestures may be specific to a given culture.

4. Emotions are not unique to humans and may be found in a variety of species.

5. Particular muscle movements may signal a particular emotion.

Let’s begin by considering the muscles in our faces. There are more than 50 muscles in the human face, far more than are needed for eating, language, or closing the eyes alone. Why do we have these muscles in the face? One answer for psychologists is that these muscles have evolved for the expression of emotion. In fact, the ability to quickly express and to recognize these expressions gave humans an important means of communication. Darwin suggests that these expressions are displayed involuntarily and also exist in non-human animals for purposes other than social communication. Darwin emphasized that facial expressions play an important role in preparing an organism for taking in information from the environment and acting on that information. Thus, facial expressions of emotions have a long evolutionary history that predates social communication.

Darwin also saw patterns related to approach or withdrawal, which is described as valence in current emotional theories. Overall, for Darwin, opposite internal states produce the opposite external movements from those of the principle one. That is to say, we shrug our shoulders when we feel helpless because it is the opposite set of movements from when we feel aggressive.

As can be seen in the illustration (see Figure 10-9) from The Expression of Emotion, a hostile dog has its ears up, its tail up, its eyes fixed, its back elevated, and so forth. The opposite internal state according to Darwin would result in the opposite external manifestation with its ears down, its tail down, its back down, and so forth. However, as Darwin noted, these responses may be species specific. For example, although dogs and cats have different postures for fear and aggression, each species displays the opposite response for the opposite emotion.

Figure 10-9 Figures from Darwin showing opposite external movements with opposite emotions.

With emotions also come physiological reactions. For example, in rage, the face becomes red with the veins on the forehead and neck distended. Monkeys also redden from passion. Various species of animals, including humans, when frightened experience the hairs of their arms standing upright. Darwin also notes that with different emotions, the heart rate speeds up, which in turn influences the brain, which in turn influences the heart.

The idea that there are specific physiological reactions for different emotions and that the cardiovascular and cortical system mutually interact with each other are two of Darwin’s ideas from this book that were considerably ahead of their time. Darwin further notes that anger, rage, and indignation are displayed in a common manner throughout the world. In this way, it is not voluntary action or previous learning or habit that influences the expression of emotion but the organization of the nervous system.

These ideas today continue to drive research in the neurosciences (for example, Susskind et al., 2008). Susskind and his colleagues examined two emotional expressions—fear and disgust. Fear is an emotional response that has been associated with greater perceptual attention, whereas disgust has been associated with sensory rejection. Given that these emotional responses reflect opposite types of sensory processing, Darwin’s ideas would suggest that their expression would involve opposite responses. Indeed, when Susskind and his colleagues examined how the skin of the face changes in fear and disgust, they found the skin to deform in the opposite ways in these two emotional expressions, as shown in Figure 10-10.

Figure 10-10 Facial expressions of fear and disgust show the opposite patterns.

These researchers next looked at three different physiological measures during the expression of fear and disgust. These were: (1) how much air an individual was able to breathe in during each of these emotions, (2) how fast the eye was able to move, and (3) how large a visual area were individuals able to see. Again, fear and disgust resulted in the opposite with individuals able to take in more air, move their eyes faster, and see a larger visual area during fear and less during disgust. These authors see their research supporting Darwin’s idea that not only does emotional expression allow for social communication but that it also modifies our ability to prepare for perception and action. The connection between facial expressions and physiological changes suggests that facial expressions are more than just social signaling, important as that is, but also offer biological advantages in terms of potential perception and action.

Throughout The Expression of the Emotions in Man and Animals Darwin saw emotional expression to be universal, shaped by natural selection, having survival value, and found in humans and a variety of animal species. Darwin also helps us to think about larger “why” questions such as why do a number of species, including humans, touch one another when being affectionate, or weep when feeling grief, or show their teeth when angry. Using careful observation, Darwin sought to articulate the specific muscles involved in many facial expressions including surprise, fear, helplessness, disgust, guilt, love, suffering, shame, and blushing. Current neuroscience research shows that specific facial expression in mice in response to emotional stimuli can be classified in distinct categories and related to specific brain activity (Dolensek, Gehrlach, Klein, & Goglla, 2020).

Darwin also sought to demonstrate the universality of emotion recognition by showing different emotions to people. For example, he showed pictures displaying surprise to some 24 people and reported that all but two reported some variation of surprise or astonishment (p. 279). Darwin was clearly using his work to forward his argument of universal expression of emotion, as he said in the concluding chapter, “I have endeavored to show in considerable detail that all the chief expressions exhibited by man are the same throughout the world” (p. 355).

Universal Emotionality

By the end of the 20th century, researchers such as Paul Ekman had followed Darwin’s tradition by studying facial expressions cross-culturally and demonstrating the universality of emotional expression (Ekman, 1973). For example, Ekman performed interesting research in New Guinea by showing individuals different emotional facial expressions and asking them to tell a story that causes the person to look the way they were in the picture (Ekman & Friesen, 1971). He also performed the research in reverse manner in which a story was told without using emotional terms. The person was then asked which of a series of emotional faces would best represent the person in the story. This type of research supported the idea that both emotional recognition and emotional expression were universal.

Let’s think about the task. How did you come to recognize the facial expressions that you see? It has been estimated that human faces can produce more than 10,000 different expressions (Ekman, 2003). Clearly one aspect of it is experience. You hear others commenting on someone’s expression and giving it a label. However, if your recognition of emotions was totally through your culture, as some researchers thought, then we might expect to see different cultures having different expressions even for such basic emotions as fear or disgust or surprise. Popular culture has taken these basic facial expressions and turned them sideways to create emoticons. Thus, a happy face becomes:-) or J and a sad one:-(or L

Like many in psychology in the 1950s, Paul Ekman assumed facial expressions to be socially learned and largely influenced by culture (Ekman, 1957). However, his own cross-cultural work and that of others forced Ekman to adopt the opposite position. Ekman asked if emotional expression differed across cultures (see Ekman, 1999b for an overview). He presented a series of emotional faces to people in five different countries: Chile, Argentina, Brazil, Japan, and the United States.

What Ekman found echoed what Darwin had suggested years earlier: Facial expressions can be seen as universal. As noted previously, Ekman later confirmed this by observing facial expressions displayed by isolated tribes in New Guinea who had no contact with Western culture or seen television, movies, or photographs. Facial expressions research is described in the box: Applying Psychological Science: An Ingenious Way to Look at Facial Expressions.

Applying Psychological Science: An Ingenious Way to Look at Facial Expressions

If you were asked to create experiments to understand the role of innate patterns of reaction and the role of culture in facial expressions, how might you do that? You could of course do what Paul Ekman did and study how emotional expressions are understood in different cultures around the world. You would have even stronger support for your conclusions if the cultures you studied did not have much contact with other cultures through media and television. If people in each culture displayed different facial expressions for a particular emotion, then you could conclude that an individual would have learned their facial expressions from their own culture. If, on the other hand, the facial expressions were more similar around the world, then you would have more support for the idea that emotional expression was universal. How else might you answer this question?

One ingenious set of studies used a group of individuals who could not have seen the facial expressions of others. They studied individuals who had been blind all their life (Galati et al., 1997). In performing the study, they created a number of stories designed to produce specific emotions. In particular these stories elicited joy, disgust, anger, fear, sadness, and surprise. These stories were read to both blind and sighted individuals. In addition, both the sighted and blind individuals were asked to pose the facial expressions associated with these emotions.

In order to rate the emotional expressions they had experts use a coding system for describing facial expressions. These researchers found that both sighted and blind individuals produced similar facial expressions. However, the blind participants used a smaller set of facial muscles. In both groups, emotions such as joy were more adequately produced. These researchers concluded that blind individuals were capable of performing emotional expressions voluntarily. Clearly, internal emotions are expressed in facial expressions whether one has seen facial expressions or not.

Thought Question: What other kinds of questions concerning whether a particular human experience or behavior is universal or culturally determined could you study using this approach?

Display Rules Across Cultures

If facial expressions are universal, how are cultural factors involved? That is, are there rules for how emotions are displayed? For example, smiles appear to be seen all over the world in humans. However, there are cross-cultural differences in terms of when and how to display smiles. In a clever series of studies, Ekman and others have shown that, although the ability to recognize an emotional expression may be universal, people do not always allow themselves to make the expression. That is, one characteristic of humans is that we are able to regulate our emotions and their expression (Tottenham, 2017).

To examine emotional expression cross-culturally, Paul Ekman showed films of surgery and accidents to Americans and Japanese individually (see Ekman, 1999b). When they were viewing the films alone, people from both cultures showed the same facial expression to the films. However, if there was an experimenter in the room with the person while they were watching the films, the Japanese more than the Americans would not fully display their emotional reactions. Thus, situational and cultural factors can influence emotional expression. These are called “display rules.”

In order to better understand display rules, David Matsumoto and his colleagues examined emotional expression in some 32 countries (Matsumoto et al., 2008). As would be expected, across the world, people are more willing to express their emotions in groups they are a part of as compared to strangers.

Another distinction that was made by these researchers was whether the culture emphasized individualism versus a collective approach. For example, the United States emphasizes the individual and his or her achievement. On the other hand, some countries such as China define people in terms of the group they are a part of. Figure 10-11 shows the relationship between emotional expression and individualism in the countries studied. As you can see, there is a positive correlation between the amount of emotional expression and the degree of individualism across countries. That is, those whose culture stresses individualism are more likely to show their emotions than those whose culture emphasizes the group.

Figure 10-11 The relationship between emotional expression and individualism.

Source: Matsumoto, Yoo, and Fontaine (2008).

Evolutionary Perspectives of Emotionality

The basic perspective from the standpoint of evolutionary psychology is that emotions evolved for their adaptive value in dealing with fundamental life tasks (Ekman, 1999a; Al-Shawaf, Conroy-Beam, Asao, & Buss, 2016). Fundamental life tasks are universal human predicaments such as losses, frustrations, and achievements. Specially, these events can include fighting, falling in love, escaping predators, and so forth (Tooby & Cosmides, 1990). The important implication is that our current emotional expression and experience is directly influenced by our ancestral past. In general, similar cortical and neurochemical mechanisms involved in emotional experience and expression can be found across a variety of species. For example, current research suggests that facial expressions seen in primates during play and during submission map onto the human expressions of laughter and smiling, respectively (Ekman, Campos, & de Waal, 2003).

One researcher who has connected emotionality with basic life tasks is Jaak Panksepp. Panksepp (1998, 2004, 2017) suggested that there are basic systems from which emotions develop. These systems are anger, fear, sexual lust, maternal care, separation distress, and social bonding, as well as playfulness and a resource acquisition system. He further suggests that these can also be seen to be related to particular psychopathologies. Below are the emotional systems and the psychopathologies that develop from them.

1. Anger or rage is evoked when there is stiff competition for resources. This system can also be aroused by restraint, frustration, and other irritations. Out of this system can emerge irritability, contempt, and hatred. Psychopathologies associated with this system would be those involving aggression, such as conduct disorders in children, psychopathic tendencies, and personality disorders.

2. Fear is evoked when the organism is in the presence of danger. This system will evoke freezing at low levels of arousal and flight at higher levels. Research suggests that external stimuli may be processed at fast, but less-conscious, levels through low-level brain circuits or slower, but more accurately, at high cognitive levels. Out of this system can emerge simple anxiety, worry, and psychic trauma. Psychopathologies associated with this system include generalized anxiety disorder (GAD), phobias, and various forms of post-traumatic stress disorder (PTSD).

3. Sexual lust becomes manifest during puberty, although the basic components of the system exist early in the development of the organism. Out of this system can emergeerotic feelings, as well as jealousy. Psychopathologies associated with this system include fetishes and sexual addictions.

4. Care systems are designed to allow us to nurture one another. Out of this system can emerge nurturance, love, and attraction. Psychopathologies associated with this system include dependency disorders, attachment disorders, and aloofness.

5. Separation distress is seen when a young organism is separated from its mother. In a variety of species, the infant will cry out in these situations. Extreme cases become more of a panic situation. Panksepp suggests that these feelings of abandonment may build on early pain circuits. Out of this system can emerge sadness, guilt, shame, and shyness. Psychopathologies associated with this system include panic attacks, pathological grief, depression, agoraphobia, and social phobia.

6. Play is seen in a variety of species and is often accompanied by the expression of joy and laughter. As we saw earlier, play is considered an important preparation for later social life. Out of this system can emerge joy and happy playfulness. Psychopathologies associated with this system include mania and disorders of hyperactivity, such as attention deficit hyperactivity disorder (ADHD).

7. The seeking system controls our desire to find and harvest the resources of the world. Across species, it is related to the motivation to obtain resources from the environment. In humans, it is connected with goal-directed urges and positive expectations concerning the world, as well as with awareness and appraisals of the world. Out of this system can emerge interest, frustration, and caring. Psychopathologies associated with this system include obsessive compulsive disorders (OCD), paranoid schizophrenia, and addictive disorders.

CONCEPT CHECK

1. Explain why it has been difficult for researchers to settle on a single definition for emotion.

2. Describe four methods that have been used to study emotions scientifically.

3. Charles Darwin used a categorical approach to studying emotions, while Wundt emphasized the dimensions of emotions. How can we understand emotions as both categories and dimensions?

4. What important contributions did Charles Darwin make to our study of emotions?

5. Describe Paul Ekman’s research to determine whether emotional expression is universal or culturally determined. What was his conclusion?

6. In what ways do “display rules” impact emotional expression?

7. What are the seven basic systems that Jaak Panksepp proposed for understanding how emotions evolved because of their adaptive value in dealing with fundamental life tasks?

Nature of Basic Emotions

What is a basic emotion? One way to answer this question is to consider what criteria are common to all emotions. Ekman suggested a set of characteristics common to all emotions (Ekman, 1999a). They are:

1. distinctive universal signals—By this Ekman is referring to a distinctive facial expression that goes with each of the basic emotions. As illustrated by the facial expressions presented by Darwin or the experimental procedure described by Ekman, a specific facial expression is associated with each of the basic emotions.

2. emotion-specific physiology—This means that underlying emotional states are distinctive patterns of physiological activity expressed in the central and autonomic nervous systems. Indeed, in a variety of studies it has been shown that autonomic nervous system activity displays different patterns for anger, fear, disgust, and sadness.

3. automatic appraisal mechanism—The basic idea is that there is a very fast—usually out-of-awareness—process that allows for appraisal of both internal and external stimuli.

4. universal antecedent events—In sadness, for example, there is a loss of someone or something significant to the person.

5. distinctive appearance developmentally—This suggests that each emotion may appear developmentally across individuals in the same order.

6. present in non-human primates—Current research, as well as Darwin’s observations, suggests that non-human primates share most if not all emotional expressions with humans.

7. quick onset—The basic idea is that emotions are quick and that is their survival value. You see something disgusting, have a reaction, and move away.

8. brief duration—The basic idea is that emotions are short term.

9. unbidden occurrence—The basic idea is that emotions are spontaneous. This simply means that individuals do not plan to have an emotional reaction.

One current example of these characteristics of emotions is that of LeDoux’s (1994) research. He describes the presence of a second visual system that runs through the mid-brain, allowing for quick responses without the visual clarity of our normal visual system. Such a system might cause you to jump as you walk through the woods if you see a snake-like structure on the ground in front of you. It is only through the slower normal visual system that you can make a distinction of whether what you saw was a snake or a stick. From an evolutionary self-preservation perspective, it is better to be wrong and think a stick is a snake than vice versa. The basic idea is that emotions are quick and that is their survival value. You see something disgusting, for example, have a reaction, and move away.

For clarity, it is important to distinguish emotions from moods, which are more long-lasting. It is also possible to turn an emotion into a mood by the continued presence of the stimuli or by talking to yourself about the situation. Neuroscience research involving emotions are sometimes referred to as affective neuroscience.

A number of researchers including Ekman followed Darwin’s lead to suggest there is a finite number of basic emotions (Tomkins, 1965). In the 1980s Silvan Tomkins articulated the basic theoretical ideas that directed emotion research during the last quarter of the 20th century. One idea is that affect is a separate system and works as an amplified response, which gives a sense of urgency to basic cognitive processes as memory, perception, thought, and action (Tomkins, 1984). Another one of Tomkins’s ideas was that the body response produced by emotions is centered on the face.

Various researchers have described these in slightly different terms, although most include anger, disgust, fear, happiness, sadness, and surprise. Sometimes contempt is included, although this shows less universality across studies (Elfenbein & Ambady, 2002). The analogy to this approach is similar to seeing colors. With colors, there are basic primary colors recognized by all people from which combinations may be made. Similarly, basic emotions can combine to have complex blends or combinations.

Classic studies in facial recognition have been conducted by Paul Ekman and Carroll Izard and others over the past 40 years, suggesting universality in emotional facial recognition in both literate and preliterate cultures. A meta-analysis describing almost 100 separate studies with over 20,000 participants further supports the existence of these emotional universals (Elfenbein & Ambady, 2002). As would be expected, emotions are most accurately rated if they are judged by the same national, ethnic, or regional groups that expressed the emotion. As with language, environment plays a role in shaping the expression and recognition of basic emotions.

Underlying Dimensions of Emotionality

In the late 1800s, Wundt sought to find the elements that underlie emotionality (Wundt, 1896). He constructed three-dimensional variables. The first was a dimensional scale ranging from pleasure to displeasure, which is referred to as valence. The second was a scale ranging from tension to relief referred to as arousal, and the third was a scale ranging from excitation to calm referred to as power. Over the years these dimensions have come to be described as valence, arousal, and power. Most recent utilizations of this approach have emphasized valence (positive—negative) and arousal (activation—deactivation) as underlying the experience of emotionality (Russell, 1980, 2003, 2009). Power is typically not included in this conceptualization.

In order to test this, James Russell asked individuals to rate a variety of emotional words. Russell’s model suggests the experience of any emotion can be seen as reflecting a point related to the degree of arousal and the degree of pleasure (Russell, 1980). This can be diagramed, as shown in Figure 10-12.

Figure 10-12 A graphical representation of the circumplex model of affect with the horizontal axis representing the valence dimension and the vertical axis representing the arousal or activation dimension.

Source: Posner, Russell, and Peterson (2005).

The dimensional approach emphasizes the experience of emotionality and sees pleasure and displeasure as core concepts (Barrett, Mesquita, Ochsner, & Gross, 2007). It also emphasizes the situational and cultural variants in emotional experiences. However, brain-imaging studies have shown that different arousal and valence states are reflected in different patterns of brain activation (Baucom, Wedell, Wang, Blitzer, & Shinkareva, 2012).

In another series of studies, Peter Kuppens and his colleagues examined the relationship between valence and arousal (Kuppens, Tuerlinckx, Russell, & Barrett, 2013). What they found was that arousal increases as one approaches the extreme stages of valence. That is, high arousal is associated with feeling miserable as well as feeling happy. There is less arousal with feeling states found in the middle of the valence continuum. They also found that when reporting similar feelings, there are great individual differences in terms of valence and arousal. This suggests that the valence—arousal dimensions are not universal for every person. Further, it is possible for a person to have mixed emotions and actually feel happy and sad at the same time (Russell, 2017).

Historical Theories of Emotionality

Historically, emotions have been described in terms of three separate components. These are the physiological response, the behavioral response, and the emotional experience or feeling. Further the physiological response has been divided into that of the brain and that of the bodily response, such as heart rate and blood pressure changes. At the end of the 19th century and throughout the 20th century, three major approaches were suggested to describe the nature of emotion generation. These were the James—Lange theory developed in the 1880s, the Cannon—Bard theory developed in the 1920s, and the Schachter—Singer theory developed in the 1960s. One key element in these theories was the role of the brain and the role of the peripheral physiological activity.

James-Lange Theory

William James’s theory of emotions evolved out of his understanding of the research of his day (James, 1884). At that time, sensory processing and movement processes were well studied in terms of their relationship to the brain. James, who thought that humans have more instincts than other animals, places the creation of emotions within this context. That is, we see a bear and react in an automatic manner. Our heart rate increases and we may tremble. For James, our experience of these bodily manifestations is the emotion. That is, we see a bear, our body reacts, and we call the experience of this reaction an emotion. In this way he turned the common sense sequence of events backwards. Carl Lange developed a similar theory independently and thus today we refer to the James—Lange theory of emotion. Overall, the James—Lange theory of emotion suggests our experience of emotion occurs from peripheral activity in our body rather than from the brain’s initial reaction.

Cannon-Bard Theory

Walter Cannon, who was a physiologist at Harvard and a former student of James, suggested that the peripheral physiological responses to seeing a bear, for example, were too slow to precede the experience of an emotion (Cannon, 1927). Further, he suggested that we see similar reactions, such as increased heart rate, to a number of environmental stimuli, making it difficult to experience different emotions from non-brain physiology alone. Working with a doctoral student of his, Philip Bard, Cannon and Bard offered an alternative to the James—Lange theory of emotion some 40 years later. Unlike the James—Lange theory in which one step is followed by another, Cannon and Bard suggested that brain and body physiological reactions could occur at the same time. Thus, you can experience an emotion as created by your brain and a bodily reaction produced separately.

Schachter-Singer Theory

Some 40 years after the Cannon—Bard theory was published, the social psychologists Stanley Schachter and Jerome Singer suggested a combination of the James—Lang and Cannon—Bard theories (Schachter & Singer, 1962). This came to be referred to as a two-factor theory of emotion and the cognitive-arousal theory of emotion. The first factor was the suggestion that the physiological response to many emotional events was basically the same. That is, there is physiological arousal associated with many emotional events involving happiness, surprise, fear and anger. This arousal was then interpreted according to the situation and thus received a label. In this way, you experience arousal and then seek an explanation to understand this arousal.

They tested this idea by giving adrenaline, which produces arousal, to groups of participants (Schachter & Singer, 1962). One group was told they would experience the symptoms associated with adrenaline such as a higher heart rate. The other group was told that they were injected with vitamins and would not experience anything. After the injection, they met a confederate of the experimenters who either acted in a manner that would provoke a happy or angry response. In response to the experience of arousal, the second group reported that they were feeling either happy or angry, whereas the first group attributed their reactions to the adrenaline. Thus, the Schachter—Singer theory suggests that your experience of an emotion is based on both basic internal reactions as well as your interpretation of these experiences.

Physiological Systems Involved in Emotion

Which parts of the brain are important for the processing of emotional information? A number of studies in a variety of species including humans are beginning to answer this question (Bennett & Hacker, 2005). Although various brain areas are involved with different emotions, it is not the case that one brain area is only involved with one emotion. Rather a number of networks involving different brain areas are involved with different emotions (Kragel & LaBar, 2016). Using statistical techniques, it is possible to show which brain areas show activation during particular emotions, such as surprise, fear, anger, and sadness (Kragel, Knodt, Hariri, & LaBar, 2016). Figure 10-13 shows the results from one such network analysis.

Figure 10-13 Areas of the brain associated with the experience of discrete emotions. Notice that different areas of the brain are involved with different emotions.

Source: Kragel, Knodt, Hariri, and LaBar (2016).

It is important to realize that the neural organization involved in emotionality can span multiple levels of the brain depending on the nature of the emotional response (see Tucker, Derryberry, & Luu, 2000, for an overview). For example, at the brain stem level including the pons, one can see basic representations of laughing and crying. The basic brain stem level controls many of the basic physiological processes involved in movement, chewing, eye movement, and facial expression as well as levels of arousal involving the sympathetic and parasympathetic nervous systems. Even in rare cases when an infant is born with only a brain stem, he or she is still able to show facial displays of pleasure and distress. When this occurs, it is difficult to distinguish emotional responses from those involved in motivational processes. In fact, some researchers have suggested that emotion is always involved in motivation to action or its inhibition.

Emotionality involves our total body (de Gelder, 2016). When we are walking in the woods or on a dark street in the city at night, a slight sound can quickly give us an emotional reaction of surprise or fear. In this case our sensory systems play an important role. The autonomic nervous system, which will be discussed in detail in the next chapter, can increase our heart rate and blood flow in relation to an unexpected event. Overall, this gives us the experience of arousal. The autonomic nervous system is regulated by the hypothalamus, which is also important for motivation. Thus, the brain is crucial for both motivation and emotion.

As you read previously, the hypothalamus is part of a system referred to as the limbic system. Other areas, as shown in Figure 10-14 of the limbic system, are parts of the thalamus, the amygdala, the hippocampus, and the cingulate gyrus. The limbic system is sometimes referred to as the emotional brain in the same way that the occipital lobe is referred to as the visual brain. Of course, emotional processing does not take place totally in only one area of the brain without connections to other cortical networks.

Figure 10-14 Structures and areas in the limbic system. The limbic system is associated with emotional processing.

One of the first reviews of the brain-imaging literature suggested that particular brain areas are involved with different tasks that reflect different emotions (Phan, Wager, Taylor, & Liberzon, 2002). They found six specific relationships. First, the medial prefrontal cortex has a general role in many emotional tasks. Second, fear specifically engages the amygdala. Third, sadness was associated with activity in the subcallosal cingulate. Fourth, if the person viewed emotional material, then the occipital lobe was activated along with the amygdala. Fifth, if memory or imagery was used to create the emotional experience, then the insula and anterior cingulate was activated. The insula, which is involved in our sense of self, is also involved in our experience of emotion (Craig, 2016). And sixth, in emotional tasks that required cognitive effort, activation was seen in the anterior cingulate and the insula. Let us now turn to specific brain areas involved in emotion.

The type of task is critical. Emotional memory tasks involve the hippocampus to a greater extent than some other structures. Fear processing includes the amygdala. Seeing emotional faces includes the fusiform face area (FFA) of the temporal lobe. Overall, in research utilizing emotional stimuli and emotional responses, the limbic system has been shown to be critical.

One prime brain structure for involvement in emotion is the amygdala (see Adolphs, Tranel, Damasio, & Damasio, 1994; Méndez-Bértolo et al., 2016). The amygdala, as the name implies in Latin, is an almond-shaped structure found on each side of the brain. It is a subcortical area found in the frontal part of the temporal lobe. The amygdala receives processed sensory information and also has a direct connection to the olfactory bulb. Structures involved in memory and attention such as the hippocampus, basal ganglia, and basal forebrain connect to the amygdala. The amygdala also has direct connections with the frontal lobes, which are involved in planning and decision-making. Given these connections, the amygdala sits between external information brought in through our sensory systems and the necessary attentional, memory, and emotional responses.

The amygdala shows faster responses when confronted with threating stimuli as opposed to pleasant ones (Méndez-Bértolo et al., 2016). In electrophysiological studies with primates, the amygdala shows the highest levels of responding to threatening face displays. On the other hand, scenes of grooming or huddling show less responding. There are actually two amygdala, one on each side of the limbic system. With humans, brain-imaging studies show greater left amygdala activity when viewing fearful faces as opposed to happy ones. The level of change in amygdala activity correlates with the intensity of the expression. There is also data to show that you make a larger amygdala response when seeing fear faces in individuals of your own culture than in individuals of another culture (Chiao, 2018).

Both humans and monkeys who have had damage to this area do not respond appropriately to fearful faces, as was the case of SM described in the feature Real World Psychology later in this chapter. Lack of sleep can also influence the connection between the amygdala and the frontal cortex, which results in problems in emotional recognition and expression (Goldstein & Walker, 2014).

Humans normally remember emotional material better than non-emotional material and this can even influence future learning (Tambini, Rimmele, Phelps, & Davachi, 2017). With damage to the amygdala, this is not the case. Most recent research with the amygdala extends the view of the amygdala processing negative emotions to a structure involved in any event that may have major negative significance for an individual. In non-human primates, there is a long tradition showing the role of the amygdala in social processes, especially those related to dominance. Monkeys normally establish dominance hierarchies with the alpha male being the one in charge. Following damage to the amygdala, the monkey would no longer display any aggressive behavior. Overall, the amygdala is seen to play an important role in the evaluation of both emotional and social processes.

The amygdala has projections that go to the temporal lobe. This allows it to be involved in emotional recognition involving both emotional face perception and emotional memories. The area of the right temporal lobe, the fusiform gyrus, appears to respond selectively to faces as compared to other types of complex visual stimuli, and networks with the amygdala are thought to process the emotional content of the face. In terms of memories, scientists make the distinction between explicit memories and implicit memories. In relation to emotionality, implicit memories would involve the internal feeling or how one felt in a particular situation and explicit memories would involve details of the external situation. These two aspects of emotional memory are influenced differently by damage to the amygdala and areas of the temporal lobes (Bennett & Hacker, 2005). Damage to the amygdala interferes with emotional memories that are implicit but not explicit. Damage to areas of the temporal lobe on the other hand do the opposite. It interferes with explicit memories but not the implicit ones. Thus, with temporal lobe damage you could remember feeling a certain way but not the situation in which it occurred.

Another part of the brain involved in emotional processes is the prefrontal cortex, especially the bottom third of it, which is called the orbitofrontal cortex (see Berridge, 2003 for an overview). In a variety of studies, the left frontal area has been seen to mediate positive affect, whereas the right is related to negative affect. Neurons in the prefrontal cortex have been shown to fire when the organism sees foods it likes. However, unlike the amygdala, damage to the prefrontal cortex does not result in a loss of emotional reactions. The involvement of this area in emotionality appears to be of a higher level. For example, individuals with damage to this area appear not to incorporate the emotional consequences of their own actions into their everyday behaviors. It has also been suggested that this area is related to our ability to induce an emotion in ourselves through cognitive means or to reduce an emotional reaction.

As we saw in the chapter on brain evolution, the complexity of the human brain has allowed for a type of emotional functioning different from that of other animals. We can think about our emotions. We can inhibit them. We can voluntarily create them. They also influence our cognitions (Phelps, 2006). Difficulties in emotional control and regulation are associated with a number of mental disorders including schizophrenia (Sheppes, Suri, & Gross, 2015; Kring & Elis, 2013). As Hughlings Jackson noted, our higher level cognitive processes can re-represent and thus transform the lower level emotional processes. In such a process we can add new features to an emotional reaction. We can also experience emotional responses to symbolic objects such as the flag of one’s country or religious symbols as well as music and art. At times, an individual has a disorder that makes emotional recognition difficult. One such example is described in the box: The World Is Your Laboratory: What If You Couldn’t Feel Fear?

The World Is Your Laboratory: What If You Couldn’t Feel Fear?

In 1994, a case study was published in the journal Nature concerning a woman who had a rare genetic disorder (Adophs, Tranel, Damasio, & Damasio, 1994). This genetic disorder called Urbach—Wiethe disease resulted in almost complete destruction of the amygdala on both sides while sparing other brain structures. The destruction of the amygdala in individuals with this disorder begins at about 10 years of age. At the time of this first report, SM, as she was referred to, was 30 years old. She was cheerful and showed no problems as she completed personality and IQ tests. In fact, her social behavior was indiscriminately trusting and friendly.

Since the amygdala is associated with the experience of emotions, the researchers sought to determine her experience of emotions. To do this they showed her pictures of faces, each with a different emotional expression. These facial expressions included happiness, surprise, fear, anger, disgust, sadness, and a neutral expression. Her results were compared to others who showed brain damage but not of the amygdala. Although she could recognize and remember faces without any problem, emotional expression was more difficult for her. She rated the faces of fear, anger, and surprise less intense than did the other participants. She also had difficulty when a single face portrayed complex emotions.

During the years that followed this initial report, SM participated in a number of studies (Adolphs, Gosselin, Buchanan, Tranel, Schyns, & Damasio, 2005; Feinstein, Adolphs, & Tranel, 2016). Consistently, she has shown the inability to recognize fear from facial expressions. However, she can recognize fearful natural scenes or fear from a person’s tone of voice. The question that arose was where did she look when she saw a face? To answer this question, the researchers showed her, and a set of control participants, more than 3,000 faces that varied in gender and were either happy or fearful. Through a series of studies, it became clear that when SM looked at faces, she did not look at the eyes. The eyes are important in the display of fear as they are opened wide with the upper eyelids raised. As can be seen in Figure 10-15, SM looked in the area of the nose and did not look at the eyes. Looking at the mouth makes it easier to perceive happiness but not fear. However, if instructed to look at the eyes, SM still did not recognize fear.

Figure 10-15 The location of where individuals look when viewing emotional faces. SM does not look at the eyes.

Even more interesting was that SM showed no reaction to experiences in which she was directly involved (Feinstein, Adolphs, Damasio, & Tranel, 2011). Although she reported not liking snakes, when the researchers took her to a pet store, she walked over and picked up one of the snakes without showing any fear. Likewise taking her to a “haunted house” or showing her emotionally evocative films did not elicit fear in SM as it did in control participants.

Where other individuals show fear, SM showed interest and arousal. In fact, in everyday situations that are dangerous, SM did not avoid danger. This resulted in her being held up at gun point as well as nearly killed in an act of domestic violence. Without the amygdala as part of larger networks, different aspects of the evolutionary value of emotional experiences are lost. However, the psychologists who work with SM see her as a survivor (Feinstein, Adolphs, & Tranel, 2016). In 2015, she celebrated her 50th birthday.

Thought Question: What if, like SM, you couldn’t feel fear? How would your everyday life be affected?

CONCEPT CHECK

1. What are the nine characteristics that Paul Ekman suggests are common to all emotions?

2. Various researchers have slightly different lists of basic emotions. What is your list of basic emotions?

3. Wilhelm Wundt introduced the concept of looking at the underlying dimensions of emotionality by specifying three dimensions: valence, arousal, and power. Over time, how have these three dimensions changed in meaning and in our understanding of how they are related?

4. Three major approaches have been suggested to describe how emotions are generated. What are they? What is the unique contribution of each of them?

5. How would you describe how different brain areas are involved with different emotions, for example, is it a one-to-one matching, all brain areas are involved with all emotions, or something else?

6. In what ways does emotionality involve our total body?

7. What system is referred to as the emotional brain? What structures are part of that system?

8. The amygdala is a central player in emotionality. List at least five processes or tasks in which it plays an important role.

9. “The complexity of the human brain has allowed for a type of emotional functioning different from that of other animals.” List at least four ways in which this is true.

Summary

Leaning Objective 1: Discuss the processes that influence how people are motivated.

Motivation is defined as the process that makes a person move toward a goal-directed behavior. Psychologists focus more on the mechanisms that create the states traditionally referred to as needs and drives. One characteristic of needs or drives is that there is a goal state that is sought. We can think of experiences such as being hungry as having the goal of finding food. We can also describe the subjective experience of feeling satisfied after eating. On a physiological level, we can consider the changes that take place in the gastrointestinal system and the brain structures that interact. One term used to describe this process is homeostasis.

Maslow’s Hierarchy of Needs pyramid describes five basic sets of needs: (1) physiological needs such as hunger, thirst, sleep, breathing, and sexuality; (2) safety needs, which include the need for security, stability, protection, and order; (3) belongingness and love needs, which include the desire to be part of a family or group; (4) esteem needs, which include the desire for achievement, mastery, competence, and independence; (4b) a subset of esteem needs, which include the desire for reputation, prestige, status, and appreciation; and (5) the need for self-actualization, representing a person’s desire for self-fulfillment.

To perform behaviors for the seeking of rewards is referred to as extrinsic motivation. We perform behaviors because we enjoy it. We play video games, listen to music, read books, or exercise for the experience itself. This is referred to as intrinsic motivation.

Learning Objective 2: Summarize the mechanisms that affect our motivation for food.

Food plays an important role in the life of humans. On a basic level, we need food to supply energy to support our daily functioning. The desire for food can be seen on a number of levels going from culture to genes. Food also plays an important role in our social and cultural life.

Feeling hungry and feeling full is also a homeostatic system that balances the intake of calories and their expenditure to perform the functions of our body. This is a complex system that monitors energy available and that involves both our gastrointestinal (GI) system and the brain. In fact, our brain is a major component of metabolism that is involved in the creation of energy. Over the past three decades, research involving appetite regulation has identified numerous hormones that influence feeling hungry and feeling full. It is also these mechanisms that keep our weight fairly stable

There are three pillars for understanding how the brain controls appetite. The first pillar is neurons in the hypothalamus that, when activated, make us feel hungry. These are referred to as AGRP (agouti-related protein) neurons in that they produce a protein which acts to increase appetite. The activity of these neurons is more involved with food seeking rather than its consumption. The second pillar is circuits of neurons involving the lateral hypothalamus. These circuits are related to the consumption of food and the positive effects of eating. The third pillar is neurons in the hypothalamus that suppress eating when activated. They produce a protein referred to as CGRP (calcitonin gene-related peptide). After we eat food, hormones are released in the gastrointestinal system. These hormones signal a number of factors including the nature of the foods eaten, and, in turn, go to our brain, especially the hypothalamus. In one part of the hypothalamus, there are two different sets of neurons.

CDC data suggest that 33.9% of Americans over the age of 20 are obese and 34.4% are overweight. There is a difference in these statistics by state. All states show an increase in obesity over the past 20 years. In terms of adolescents, there has also been an increase in obesity for both boys and girls in the latest data over 20 years. The three major eating disorders are anorexia nervosa, bulimia nervosa, and binge-eating disorder.

Learning Objective 3: Explain the factors that affect our sexual motivation.

Sexuality is a driving force in many species including humans. Most primates only engage in sexual activity when there is a high probability of producing offspring. Humans, on the other hand, may engage in sexual activity at any time. Humans use the internal experience of sexual arousal and the external experience of sexual activity for a variety of purposes. This suggests that sexual activity for humans goes beyond basic motivation and has an important pair bonding and social component.

Humans have depicted sexual activities in paintings and carvings for thousands of years. Some of the more famous are Etruscan ceramic plates, showing a variety of sexual positions dating from some 2,500 years ago in Italy. However, in the 18th and 19th centuries in Europe and the United States, some cultures have seen sexual activity as a negative force in human life. Also, in the 1800s, Charles Darwin, Sigmund Freud, and Havelock Ellis began to approach sexuality from a scientific perspective. In the 1930s, Alfred Kinsey conducted a large-scale survey of some 12,000 individuals across the United States. The results of these surveys were published in two books: Sexual Behavior in the Human Male (1948) and Sexual Behavior in the Human Female (1953). In 1947, the Institute for Sex Research was established at Indiana University with Alfred Kinsey as director. This was later renamed the Kinsey Institute and continues performing research related to sexuality.

In 2016, the Centers for Disease Control and Prevention (CDC) surveyed a national sample of 10,416 males and females in the United States. Among males and females 15—44 years of age, 92% of males and 94.2% of females have had vaginal intercourse. Further, 87.4% of males and 86.2% of females have had oral sex with a member of the opposite sex. Anal sex with the opposite sex was lower: 42.3% for males and 35.9% for females. In this survey, any reported same-sex contact was 6.2% for males and 17.4% for females. This included people who saw themselves as bisexual and homosexual/lesbian. This survey was updated from 2002 and 2011 surveys, which showed similar results.

In studying the sexual responses of males and females, Masters and Johnson realized that there was a similarity in how men and women experienced the sexual experience (Masters & Johnson, 1966). They identified four phases of the human sexual response, which are (1) excitement; (2) plateau; (3) orgasm; and (4) resolution.

Learning Objective 4: Discuss the scientific understanding of emotionality.

An emotion is a positive or negative feeling that is in response to a particular behavior or physiological activity. Also, emotions are not only expressed in our faces, but also in our voice and touch as when we hug one another.

One critical scientist in the study of emotions is Charles Darwin. In The Expression of the Emotions in Man and Animals, Darwin portrays a careful observation of emotionality. Throughout his book, Darwin presents drawings and photographs of people and animals as they express different emotions. The common theme is that emotions are universal and represent an example of evolution through natural selection.

By the end of the 20th century, researchers such as Paul Ekman had followed Darwin’s tradition by studying facial expressions cross-culturally and demonstrating the universality of emotional expression. For example, Ekman performed interesting research in New Guinea by showing individuals different emotional facial expressions and asking them to tell a story that causes the person to look the way they were in the picture. He also performed the research in reverse manner, in which a story was told without using emotional terms. The person was then asked which of a series of emotional faces would best represent the person in the story. This type of research supported the idea that both emotional recognition and emotional expression were universal.

Learning Objective 5: Discuss the major theories of emotion.

Historically, emotions have been described in terms of three separate components. These are the physiological response, the behavioral response, and the emotional experience or feeling. Throughout the 20th century, three major approaches were suggested to describe the nature of emotion generation. These were the James—Lange theory developed in the 1880s, the Cannon—Bard theory developed in the 1920s, and the Schachter—Singer theory developed in the 1960s. One key element in these theories was the role of the brain and the role of the peripheral physiological activity.

Several brain areas play key roles in the experience of emotion. First, the medial prefrontal cortex has a general role in many emotional tasks. Second, fear specifically engages the amygdala. Third, sadness was associated with activity in the subcallosal cingulate. Fourth, if the person viewed emotional material, then the occipital lobe was activated along with the amygdala. Fifth, if memory or imagery was used to create the emotional experience, then the insula and anterior cingulate was activated. And sixth, in emotional tasks that required cognitive effort, activation was seen in the anterior cingulate and the insula. Emotional memory tasks involve the hippocampus to a greater extent than some other structures. Fear processing includes the amygdala. Seeing emotional faces includes the fusiform face area (FFA) of the temporal lobe. Overall, in research utilizing emotional stimuli and emotional responses, the limbic system has been shown to be critical.

Study Resources

Review Questions

1. How is motivation related to learning in humans? Describe and develop a comprehensive learning environment for young children using Maslow’s hierarchy of needs.

2. From an evolutionary perspective, what is the functional role of motivation in our human history?

3. What roles do motivation and emotion play in the development and treatment of eating disorders?

4. What are the relationships between motivation and sexuality in humans?

5. What are the relationships between emotions and sexuality in humans?

6. Construct a comprehensive model of human sexuality beginning with Masters and Johnson’s model of human sexual response and incorporating other contextual factors covered in this chapter, for example, gender differences and role of culture.

7. What is an emotion? How have various researchers from different time periods answered this question? What research questions did they ask? What is your answer to the question of what is an emotion? What research questions would you like to ask?

8. From an evolutionary perspective, what is the functional role of emotionality in our human history?

9. In what ways are emotions similar across animals and humans?

For Further Reading

✵ Asma, S., & Gabriel, R. (2019). The Emotional Mind: The Affective Roots of Culture and Cognition. Cambridge, MA: Harvard University Press.

✵ Ekman, P., Campos, J., Davidson, R., & de Waal, F. (2003). Emotions Inside Out: 130 Years after Darwin’s The Expression of Emotions in Man and Animals. New York: New York Academy of Sciences.

✵ Johnston, E., & Olson, L. (2015). The Feeling Brain: The Biology and Psychology of Emotions. New York: W.W. Norton & Co.

Web Resources

✵ CDC eating guideline—https://www.cdc.gov/nccdphp/dnpao/features/healthy-eating-tips/ and https://www.cdc.gov/healthyweight/healthy_eating/index.html

✵ HHS dietary guidelines—http://health.gov/dietaryguidelines/

✵ CDC weight—https://www.cdc.gov/nchs/fastats/obesity-overweight.htm

✵ Kinsey Institute—https://kinseyinstitute.org/

✵ CDC sexual activity—https://www.cdc.gov/nchs/data/nhsr/nhsr088.pdf

✵ Sexual attitudes—http://www.nationalsexstudy.indiana.edu/

✵ Reactions to fear—https://www.scientificamerican.com/article/feeling-our-emotions/

Key Terms and Concepts

anorexia nervosa

binge-eating disorder

body mass index

bulimia nervosa

emotions

extrinsic motivation

homeostasis

intrinsic motivation

motivations

purging

satiety

self-actualization

sexuality