Child Development From Infancy to Adolescence. Laura E. Levine

middle childhood, and adolescence to identify broad periods of development that have behaviors or characteristics that set that stage apart from the other stages. During infancy (the first year of life), children are totally dependent on their caregivers for their physical care, but they already can use all their senses to begin exploring their world. During this period, they begin developing the motor skills they will need to explore it further. They also form a strong emotional attachment to their caregivers and lay the foundation for learning language. Toddlers (ages 1–3) continue developing their motor skills and can more actively explore their physical world. Language develops at an astonishing rate during this period, and toddlers begin showing independence and autonomy from their caregivers as they learn to do things for themselves. In early childhood (ages 3–6), children learn about the physical and social world through play. As peers become more important, young children learn the skills necessary to understand how other people think and feel. During middle childhood (ages 6–12), children develop the intellectual ability to think in a more ordered and structured way and school becomes a major context for development. At this stage, children begin developing a clearer sense of self and an understanding of who they are and what makes them unique. Play and peers are essential parts of their lives. The physical changes associated with puberty mark the transition from childhood into adolescence (ages 12–18). As their bodies undergo the physical changes that move them toward adulthood, adolescents are able to think and reason at a more abstract level and they develop a stronger sense of who they are and who they want to become. Family remains important to them, but peer relationships take on a greater importance than they had before. Although this book covers the stages from infancy through adolescence, we briefly describe a stage that begins in late adolescence: the stage of emerging adulthood (ages 18–25). This stage describes the period of transition between adolescence and adulthood. During this time, many young people feel they are no longer adolescents but also recognize they are not yet ready to fully assume the role of an adult in their culture (Arnett, 2015). It represents a time to explore the possibilities open to them in the realms of education, work, and relationships before committing to choices that will shape their adulthood.

      Domains of Development

      When studying development, we distinguish between three basic aspects or domains of development: physical, cognitive, and social-emotional. Physical development includes the biological changes that occur in the body, including changes in size and strength, as well as the integration of sensory and motor activities. Neurological, or brain, development has become a major area for research in physical development. Cognitive development includes changes in the way we think, understand, and reason about the world. It includes the accumulation of knowledge as well as the way we use that information for problem solving and decision making. Social-emotional development includes all the ways we learn to connect to other individuals, understand our emotions and the emotions of others, interact effectively with others, and express and regulate our emotions.

      Physical development: Biological changes that occur in the body and brain, including changes in size and strength and the integration of sensory and motor activities.

      Cognitive development: Changes in the way children think, understand, and reason as they grow older.

      Social-emotional development: Age-related changes in the ways children connect to other individuals and express and understand emotions.

      Although it is useful to make distinctions between these domains, it is important to understand that they continually interact with each other. For instance, during puberty adolescents undergo dramatic physical changes over a short period of time, but these changes also affect social development. As adolescents grow to look more like adults and less like children, adults begin to treat them more like adults, giving them new responsibility and expecting greater maturity from them. These opportunities, in turn, contribute to the cognitive development of adolescents as they learn from their new experiences.

      

      Domains of development. When we study development, we look at changes in the physical, cognitive, and social-emotional development of children and adolescents.

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      Themes in the Field of Child Development

      We all have our own ideas about children. You brought some with you when you entered this class. Stop for a few minutes and think of a couple of sentences or phrases that capture what you believe to be true about how child development occurs. Do you believe that “if you spare the rod, you will spoil the child”? Or that “as the twig is bent, so grows the tree”? Do you think that children are like “little sponges”? Or that they grow in “leaps and bounds”? Each of these bits of folk wisdom touches on an issue that has been debated within the field of child development. Here we briefly review some of the reoccurring debates and controversies that have become themes in our field.

      Nature and Nurture

      Throughout history the question of whether our behavior, thoughts, and feelings result from nature, our genetic inheritance, or from nurture, the influence of the environment, has shaped our understanding of why we act certain ways and how we can influence human behavior. The controversy was originally described as nature versus nurture. For example, let’s say you are an aggressive (or shy, or outgoing . . .) person. Researchers wanted to find out whether you became aggressive because you were “born that way,” with your genes determining the outcome, or whether you learned to be aggressive because of what you saw or experienced in your environment. People initially argued for one side or the other, but it became clear that any developmental outcome is an interaction of both.

      Nature: The influence of genetic inheritance on development.

      Nurture: The influence of learning and the environment on development.

      Asking whether behavior is due to nature or to nurture is similar to asking whether your car needs an engine or wheels. You aren’t going anywhere unless you have both, and they are going to have to work together if you are ever going to reach your destination. The field of epigenetics has made us aware that what counts is not just what genes you have, but also what your genes are doing, and what they are doing is influenced by the environment you are in (Nesterak, 2015). We have left behind the era of “nature versus nurture” and entered the era of “nature through nurture” in which many genes, particularly those related to traits and behaviors, are expressed only through a process of constant interaction with their environment (Meaney, 2010; Stiles, 2009). We discuss these ideas further in Chapter 3.

      Continuous Versus Discontinuous Development

      Is development a series of gradual steps that modify behavior bit by bit, or does it proceed in leaps and bounds? In Chapter 2 and throughout the rest of the book, you will learn about some theories in the field of child development that describe development as a series of stages children move through, similar to the “leaps”