The content covered in this chapter will allow you to score more points on the MCAT—and to prepare for your clinical clerkships in psychiatry. This chapter is unique in that it covers not how the mind normally works, as we see in the other chapters in this book, but rather how the mind works when it is functioning abnormally. The MCAT tests critical thinking; one common way to do this is to ask what happens when a system—like the mind—is not functioning normally. Thus, this chapter covered high-yield information that is likely to appear on the MCAT because it connects all three subjects of the Psychological, Social, and Biological Foundations of Behavior section. In the next chapter, we move away from the individual as we begin to explore social psychology; from there, we’ll continue expanding outward as we move into sociology.
Understanding Psychological Disorders
· The biomedical approach to psychological disorders takes into account only the physical and medical causes of a psychological disorder. Thus, treatments in this approach are of a biomedical nature.
· The biopsychosocial approach considers the relative contributions of biological, psychological, and social components to an individual’s disorder. Treatments also fall into these three areas.
· The Diagnostic and Statistical Manual of Mental Disorders is used to diagnose psychological disorders. Its current version is DSM-5 (published May 2013). It categorizes mental disorders based on symptom patterns.
· Psychological disorders, especially anxiety, depressive, and substance use disorders, are very common in the population.
Types of Psychological Disorders
· Schizophrenia is the prototypical disorder with psychosis as a feature. It contains positive and negative symptoms.
o Positive symptoms add something to behavior, cognition, or affect and include delusions, hallucinations, disorganized speech, and disorganized behavior.
o Negative symptoms are the loss of something from behavior, cognition, or affect and include disturbance of affect and avolition.
· Depressive disorders include major depressive disorder, dysthymia, and seasonal affective disorder.
o Major depressive disorder contains at least one major depressive episode.
o Persistent depressive disorder (dysthymia) is the presence of depressive symptoms for at least two years that do not meet criteria for major depressive disorder.
· Bipolar and related disorders have manic or hypomanic episodes.
o Bipolar I disorder contains at least one manic episode.
o Bipolar II disorder contains at least one major depressive episode and least one hypomanic episode.
o Cyclothymic disorder describes periods of manic and depressive symptoms that are not severe enough to be labeled an episode. These symptoms must persist for at least 2 years and be present the majority of that time.
· Anxiety disorders capture conditions in which excessive fear or anxiety impairs one's daily functions. Anxiety disorders are differentiated by the stimuli that induces anxiety.
o Specific phobias are irrational fears of specific objects or situations.
o Separation anxiety disorder is anxiety due to separation from one's caregivers, often with the ideation that if separated, either the caregiver or the patient will be harmed.
o Social anxiety disorder is anxiety due to social or performance situations with the ideation that the patient will be negatively evaluated.
o Selective mutism disorder is the impairment of speech in situations where speaking is expected.
o Panic disorder is marked by recurrent panic attacks: intense, overwhelming fear and sympathetic nervous system activity with no clear stimulus. It may lead to agoraphobia.
o Agoraphobia is a fear of places or situations where it is hard for an individual to escape.
o Generalized anxiety disorder is a disproportionate and persistent worry about many different things for at least six months.
· Obsessive—compulsive disorder and related disorders are characterized by perceived needs (obsessions or preoccupations) and paired actions to meet those needs (compulsions).
o Obsessive—compulsive disorder is characterized by obsessions (persistent, intrusive thoughts and impulses) and compulsions (repetitive tasks that relieve tension but cause significant impairment in a person’s life).
o Body dysmorphic disorder is characterized by an unrealistic negative evaluation of one’s appearance or a specific body part. The individual often takes extreme measures to correct the perceived imperfection.
o Hoarding disorder is characterized by the reluctance of giving up one's physical possessions. Often this behavior is associated with excessive acquisition of physical items.
· Posttraumatic stress disorder (PTSD) is characterized by intrusion symptoms (reliving the event, flashbacks, nightmares), avoidance symptoms (avoidance of people, places, objects associated with trauma), negative cognitive symptoms (amnesia, negative mood and emotions), and arousal symptoms (increased startle response, irritability, anxiety). These symptoms can be explained from the behaviorist perspective.
· Dissociative disorders include dissociative amnesia, dissociative identity disorder, and depersonalization/derealization disorder.
o Dissociative amnesia is an inability to recall past experience without an underlying neurological disorder. In severe forms, it may involve dissociative fugue, a sudden change in location that may involve the assumption of a new identity.
o Dissociative identity disorder is the occurrence of two or more personalities that take control of a person’s behavior.
o Depersonalization/derealization disorder involves feelings of detachment from the mind and body or from the environment.
· Somatic symptom and related disorders involve significant bodily symptoms.
o Somatic symptom disorder involves at least one somatic symptom, which may or may not be linked to an underlying medical condition, that causes disproportionate concern.
o Illness anxiety disorder is a preoccupation with thoughts about having, or coming down with, a serious medical condition.
o Conversion disorder involves unexplained symptoms affecting motor or sensory function and is associated with prior trauma.
· Personality disorders (PD) are patterns of inflexible, maladaptive behavior that cause distress or impaired functioning in at least two of the following: cognition, emotions, interpersonal functioning, or impulse control. They occur in three clusters: A (odd, eccentric), B (dramatic, emotional, erratic), and C (anxious, fearful).
o Cluster A includes paranoid, schizotypal, and schizoid PDs. Cluster B includes antisocial, borderline, histrionic, and narcissistic PDs. Cluster C includes avoidant, dependent, and obsessive—compulsive PDs.
o Paranoid PD involves a pervasive distrust and suspicion of others.
o Schizotypal PD involves ideas of reference, magical thinking, and eccentricity.
o Schizoid PD involves detachment from social relationships and limited emotion.
o Antisocial PD involves a disregard for the rights of others.
o Borderline PD involves instability in relationships, mood, and self-image. Splitting is characteristic, as are recurrent suicide attempts.
o Histrionic PD involves constant attention-seeking behavior.
o Narcissistic PD involves a grandiose sense of self-importance and need for admiration.
o Avoidant PD involves extreme shyness and fear of rejection.
o Dependent PD involves a continuous need for reassurance.
o Obsessive—compulsive PD involves perfectionism, inflexibility, and preoccupation with rules.
Biological Basis of Nervous System Disorders
· Schizophrenia may be associated with genetic factors, birth trauma, adolescent marijuana use, and family history. There are high levels of dopaminergic transmission.
· Depression is accompanied by high levels of glucocorticoids and low levels of norepinephrine, serotonin, and dopamine.
· Bipolar disorders are accompanied by high levels of norepinephrine and serotonin. They are also highly heritable.
· Alzheimer’s disease is associated with genetic factors, brain atrophy, decreases in acetylcholine, senile plaques of β-amyloid, and neurofibrillary tangles of hyperphosphorylated tau protein.
· Parkinson’s disease is associated with bradykinesia, resting tremor, pill-rolling tremor, masklike facies, cogwheel rigidity, and a shuffling gait. There is decreased production of dopamine by cells in the substantia nigra.
Answers to Concept Checks
1. Whereas the biomedical model considers only the physical, pathological mechanisms that underlie mental illness, the biopsychosocial model considers the contributions of these biological factors along with psychology (thoughts, emotions, or behaviors) and social situation (environment, social class, discrimination, or stigmatization).
2. The following disorders occur in greater than 2 percent of the United States population per year: specific phobia, social anxiety disorder, major depressive disorder, posttraumatic stress disorder, bipolar disorder, generalized anxiety disorder, and panic disorder.
1. Positive symptoms of schizophrenia, including delusions, hallucinations (usually auditory), disorganized thought, and disorganized behavior, are likely to improve from treatment with an antipsychotic medication. Negative symptoms, including disturbance of affect and avolition, are largely unaffected by antipsychotic medications.
2. Major depressive episodes include a two-week duration of at least five of the following symptoms: depressed mood, loss of interest (anhedonia), sleep disturbance, feelings of guilt, lack of energy, difficulty concentrating, changes in appetite, psychomotor symptoms, and suicidal thoughts. At least one of the symptoms must be depressed mood or anhedonia. Manic episodes include a one-week duration of at least three of the following symptoms: elevated or expansive mood, distractibility, decreased need for sleep, grandiosity, flight of ideas or racing thoughts, agitation, pressured speech, and engagement in risky behavior.
3. Major depressive disorder contains at least one major depressive episode with no manic episodes. Bipolar I disorder has at least one manic episode with or without depressive episodes. Bipolar II disorder has at least one hypomanic episode with at least one major depressive episode. Cyclothymic disorder has hypomanic episodes and dysthymia that is not severe enough to be a major depressive episode.
4. Obsessions are persistent, intrusive thoughts and impulses that produce tension. In this case, the obsession is the patient's thought that someone will break into her apartment. Compulsions are repetitive tasks that relieve tension but cause significant impairment in a person’s life. This patient's compulsion is that she must check the latch on her apartment door five times before going to bed. Their relationship is that obsessions raise tension while compulsions relieve that tension.
Odd or eccentric
Paranoid, schizotypal, schizoid
Dramatic, emotional, or erratic
Antisocial, borderline, histrionic, narcissistic
Anxious or fearful
Avoidant, dependent, obsessive—compulsive
1. In depression, levels of cortisol are increased. Many neurotransmitter levels are reduced, including norepinephrine, serotonin, and dopamine.
2. Mutations in the presenilin genes (chromosomes 1 and 14) and β-amyloid precursor protein gene (chromosome 21) are associated with increased risk for Alzheimer’s disease.
3. Dopamine levels are elevated in schizophrenia and reduced in Parkinson’s disease. Thus, treatments for one disorder may cause symptoms similar to those of the other.
· Behavioral Sciences Chapter 1
o Biology and Behavior
· Behavioral Sciences Chapter 3
o Learning and Memory
· Behavioral Sciences Chapter 12
o Social Stratification
· Biology Chapter 4
o The Nervous System
· Biology Chapter 5
o The Endocrine System
· Biology Chapter 12
o Genetics and Evolution
Discrete Practice Questions
1. Which of the following is an example of a negative symptom seen in schizophrenia?
1. Auditory hallucinations
2. Disorganized behavior
3. Disturbance of affect
2. During an interview with a schizophrenic patient, a psychiatrist notices that the patient keeps repeating what the psychiatrist says. This phenomenon is known as:
3. loosening of associations.
3. A 42-year-old woman has always been extremely neat and tidy. She works as a secretary and stays long after normal working hours to check the punctuation and spelling of letters she prepared during the day. Her boss referred her for counseling after she repeatedly got into fights with her coworkers. “They don’t take the job to heart,” she says. “They just joke around all day.” The most likely preliminary diagnosis for this patient is:
1. obsessive—compulsive personality disorder.
2. antisocial personality disorder.
3. narcissistic personality disorder.
4. borderline personality disorder.
4. Which of the following is true with regard to a major depressive episode?
1. It may last less than two weeks.
2. It must involve thoughts of suicide or a suicide attempt.
3. It may involve a decrease in sleep.
4. It must involve feelings of sadness.
5. A 36-year-old who works from home is referred for evaluation. He is reluctant to venture out to meet with other people and rarely has people in to visit. When selected for a company-wide award, he refused to have his picture taken for the company newsletter. During an assessment, he averts his face and asks the examiner to “stop looking at me.” Although he is average in appearance, he is convinced that his face is ugly and misshapen. The most likely diagnosis for this man would be:
2. obsessive—compulsive disorder.
3. body dysmorphic disorder.
4. schizoid personality disorder.
6. A young woman of unknown age is brought by the Philadelphia police to the local emergency department for evaluation after they found her wandering in a park. She carries no purse or identification. She is unable to state her name or any details about her life, except that the name Phoenix seems familiar. The police in Arizona are contacted and find a missing persons report matching the patient’s description. Based on this information, the most likely diagnosis for this patient is:
1. depersonalization/derealization disorder.
2. dissociative identity disorder.
3. somatic symptom disorder.
4. dissociative amnesia with dissociative fugue.
7. In addition to being a freestanding diagnosis, agoraphobia is most often seen in association with which other psychiatric diagnosis?
1. Obsessive—compulsive disorder
2. Avoidant personality disorder
3. Generalized anxiety disorder
4. Panic disorder
8. A 28-year-old male comes to a clinic concerned that he has pancreatic cancer. Review of his medical records shows that this is the fourth time in the past year that the patient has appeared for medical attention. No identifiable medical problem is found. When confronted with this history, he confesses that he feels relieved after being told that all of the tests are negative, but soon becomes worried again that he has cancer. Based on the information, the most likely diagnosis for this patient would be:
1. major depressive disorder.
2. illness anxiety disorder.
3. conversion disorder.
4. narcissistic personality disorder.
9. Questions 9—10 refer to the scenario described below.
10. A physician is attempting to diagnose a patient’s mental disorder based on a set of symptoms. The confirmed symptoms currently include appetite disturbance, substantial weight change, decreased energy, a feeling of worthlessness, and excessive guilt.
9. What two disorders could these symptoms indicate?
1. Major depressive and bipolar disorders
2. Dissociative amnesia and depersonalization/derealization disorder
3. Alzheimer’s disease and Parkinson’s disease
4. Specific phobia and panic disorder
10. What should the physician ask about to distinguish between the two possible disorders affecting that patient?
1. Whether the patient has amnesia
2. Whether the patient has also had manic episodes
3. Whether the patient is irrationally afraid of anything
4. Whether the patient has experienced difficulty performing familiar tasks
11. A mother notices that her teenage son seems to have a phobia for snakes. In the past week, on several occasions, the teenager has had more severe fear symptoms than usual, without seeing or even thinking about a snake. Which mental disorder could cause this reaction?
2. Antisocial personality disorder
3. Obsessive—compulsive disorder
4. Panic disorder
12. Splitting is a defense mechanism commonly seen with which personality disorder?
1. Antisocial personality disorder
2. Borderline personality disorder
3. Histrionic personality disorder
4. Narcissistic personality disorder
13. A woman comes to the doctor with a two-week history of complete paralysis of her left arm. She has had no injury to the extremity, and full neurological workup fails to demonstrate any underlying cause. She seems surprisingly unconcerned about the paralysis, and seems more worried about an argument she had one month ago in which she hit her daughter. Based on this information, the woman’s most likely diagnosis is:
1. conversion disorder.
2. generalized anxiety disorder.
3. illness anxiety disorder.
4. histrionic personality disorder.
14. A woman notices that her father has started to move his fingers in such a way that it looks like he is rolling something, despite nothing actually being there. She also notes slowed movement and a shuffling gait. Which neurotransmitter is likely to be present in decreased levels in her father’s brain?
15. Which of the following is/are true regarding bipolar disorders?
1. They have little, if any, genetic heritability.
2. They are associated with increased levels of serotonin in the brain.
3. They all require at least one depressive episode for diagnosis.
4. I only
5. II only
6. I and III only
7. II and III only
Discrete Practice Answers
1. CNegative symptoms are the absence of normal or desired behavior, which include disturbance of affect and avolition. Positive symptoms are the addition of abnormal behavior, including hallucinations, (A), disorganized behavior, (B), and delusions, (D).
2. AEcholalia is an involuntary repetition of others’ words and utterances and may be seen in schizophrenia. Echopraxia, (B), is imitation of others’ actions. Loosening of associations, (C), is a type of disordered thought in which the patient moves between remotely related ideas. Neologisms, (D), are newly invented words.
3. AFocusing on details, loving routine, having a sense that there is only one right way to do things, and lack of humor suggests an obsessive—compulsive personality disorder.
4. CDepression is marked by a period of at least two weeks in which the patient has five of nine cardinal symptoms, one of which must be depressed mood or lack of interest (anhedonia). While decreased need for sleep is commonly seen in manic episodes, it may also appear in depression, as sleep disturbance is one of the nine cardinal symptoms. Not all depressed individuals are suicidal, as in (B). In older men, depression may often manifest as anhedonia without feelings of sadness, invalidating (D).
5. CThe central issue is the negative appraisal of his own appearance, indicating body dysmorphic disorder. Thus, it is likely that all other symptoms this patient is experiencing arise from this disorder. The other disorders listed in the answer choices cannot explain all the symptoms.
6. DDissociative fugue is characterized by sudden travel or change in normal day-to-day activities and occurs in some cases of dissociative amnesia. Symptoms include an inability to recall one’s past or confusion about one’s identity. Thus, the described patient is most likely to be suffering dissociative amnesia accompanied by dissociative fugue.
7. DAgoraphobia, or a fear of places or situations in which it would be difficult to escape, is commonly seen in panic disorder. Concern about having a panic attack in public may make these individuals fearful of leaving their home.
8. BIn illness anxiety disorder, the person is preoccupied with fears that he has—or will come down with—a serious disease, and these fears continue even after medical exams and tests have returned negative results.
The symptoms listed indicate a major depressive episode. However, depressive episodes can be a part of bipolar disorders, which also contain manic episodes. Thus, if manic episodes have not yet been asked about, one cannot distinguish between depression or bipolar disorder as the correct diagnosis yet.
10. BTo determine if this patient has major depressive disorder or a bipolar disorder, the presence of manic (or hypomanic) episodes should be confirmed. Bipolar disorders contain manic (or hypomanic) episodes, while major depressive disorder does not.
11. DExhibiting signs of panic and irrational fear without any instigating object present indicates panic disorder. The teenager may have diagnoses of both specific phobia (for snakes) and panic disorder.
12. BSplitting, the consideration of others as either “all good” or “all bad,” is characteristic of borderline personality disorder.
13. AConversion disorder is marked by a motor or sensory symptom in the absence of an underlying physical or neurological cause. It is associated with an inciting event that, in this case, may have been the argument with her daughter. Her lack of concern over the deficit is referred to as la belle indifférence.
14. CThe symptoms indicate that the woman’s father likely has Parkinson’s disease. This disease is caused by decreased dopamine production in the substantia nigra.
15. BBipolar disorders have been shown to be highly heritable and are associated with increased levels of norepinephrine and serotonin in the brain. Bipolar I disorder can be diagnosed with a single manic episode and does not require a major depressive episode. Bipolar II disorder requires at least one hypomanic episode and one major depressive episode. Cyclothymic disorder contains at least one hypomanic episode and dysthymia.
Consult your online resources for additional practice.