Developmental psychology is a sub-discipline within psychology that describes and explains the changes that people undergo over their whole life span.
Many books on developmental psychology divide the human life span into developmental periods or stages. The criteria for this subdivision are normally chronological age and biological indicators of developmental change, such as the growth spurt at the beginning of the adolescent years, menarche and menopause. However, while dividing human development into stages may help psychologists to describe and explain human development, this approach has various shortcomings, three of which are outlined below.
First, the stages of development are most frequently based on North American models of human development; therefore, a narrow application of this approach to contexts such as southern Africa may be inappropriate and misleading. For example, it is accepted that the stages of adult development are based partly on the rates of predicted life expectancy. According to the World Health Organization (n.d.), in the US the proportion of the population over the age of 60 was 19.7 per cent in 2013, while in South Africa the proportion was 8.6 per cent. In 2013, South Africa also had a much larger proportion of its population under the age of 15 years (29.5 per cent compared to 19.5 per cent). Obviously, with such disparate age markers, what is conceived of as ’normal’ adult development within the US and similar high-income contexts cannot simply be transposed to lower-income contexts such as South Africa, as is frequently the case with the application of the stages-of-development approach.
Second, the stages-of-development approach tends to gloss over the differences in development within stages, and in the process negates the uniqueness of individual development. Actual development is much more complex than this approach would lead us to believe, because individuals sometimes grow in stops and starts and at other times they grow constantly (Bukatko & Daehler, 2011).
Third, the focus on the role of biology that is typical of the stages-of-development approach frequently leads to the role of the environment being underplayed. Yet, as will become abundantly clear as you read through the chapters in this part of the book, environmental factors play a pivotal role in human development.
There are a number of important themes underlying the study of developmental psychology (Bukatko & Daehler, 2011) and reference to these will be found throughout this part of the text. The most important of these issues include the following:
•Nature/nurture. What roles do heredity and upbringing play in human development? (See Box 3.3.)
•Sociocultural context. This considers the customs, values and beliefs that influence a child’s upbringing. It includes the roles played by the parents’ economic status, educational level as well as health care and parenting style.
•Continuous/discontinuous development. Does development occur gradually or in distinct stages or steps?
Part 2 consists of two chapters, dividing the human life span into early and middle childhood (Chapter 3) and adolescence, adulthood and aging (Chapter 4). However, it should be stressed that within the context of this volume, these stages should be seen as reflecting broad approximate developmental trends, rather than as a template for all human development in all contexts (Duncan, Van Niekerk & Mufamadi, 2003). Thus, in essence, this part covers the entire human life span.
Each of the above-mentioned periods is also considered in terms of the key areas of development:
•Physical development, which includes physiological changes and motor development
•Cognitive development, which includes the development of language and thought processes
•Psychosocial development, which includes emotional development and the development of interpersonal relations (Hook, 2002).
While dividing development into these three domains allows for a comprehensive and coherent description of development during the various life stages, in reality people’s behaviour and development cannot be divided into such neat categories (Duncan et al., 2003). People are whole beings, and their development at any point in time involves a complex interaction of these three domains (Bukatko & Daehler, 2011).
It should also be noted that, although there are several theories available, Jean Piaget’s theory has been employed to describe various aspects of cognitive development, and Erik Erikson’s psychosocial theory has been used to discuss various facets of the individual’s psychosocial development. In addition, both of these theories have been criticised, in part due to concerns about their applicability in a non-Western context. The reason that we focused on these theories was to ensure a measure of continuity.
While covering most of the key areas of development normally included in standard developmental psychology texts, this part differs in terms of its sharp focus on the contextual obstacles or challenges to optimal human development confronting many South Africans. The HIV/AIDS pandemic (which has swept a path of human destruction through southern Africa) is one such contextual obstacle, and the chapters consider its impact on human development in South Africa. Apart from attempting to illustrate how this pandemic currently affects the lived reality of South Africans at various points in the human life span, we also illustrate how the pandemic, through the sheer extent of its destructive trajectory, will challenge and profoundly alter our basic assumptions and understanding of human development in years to come.
Another key issue is the notion of human resilience. All the authors contributing to this part agree that, because of human resilience, people do not necessarily succumb to the contextual obstacles confronting them. However, they generally also agree that because these obstacles may render people vulnerable to a range of risks and thereby undermine their optimal development, these obstacles should be eliminated. In this sense, the authors adopt what has been referred to as a critical social-scientific stance and so reject the outmoded notions of scientific neutrality and detachment. Instead, through their emphasis on some of the key contextual obstacles to optimal human development in South Africa, these authors clearly support an agenda of social change.
Consequently, it is hoped that the content of this part will not only provide the reader with a broad understanding of development throughout the human life span, but that it will also motivate the reader to consider the ways in which the obstacles confronting many South Africans can be addressed.