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3
Developing Through the Life Span
SURVEY THE
CHAPTER
Developmental Psychology’s Major Issues
Nature and Nurture
Continuity and Stages
Stability and Change
Prenatal Development and the Newborn
Conception
Prenatal Development
The Competent Newborn
Twin and Adoption Studies
Infancy and Childhood
Physical Development
Cognitive Development
Social Development
THINKING CRITICALLY ABOUT: Parenting Styles—
Adolescence
Physical Development
Cognitive Development
Social Development
Emerging Adulthood
Adulthood
Physical Development
Cognitive Development
Social Development
Life is a journey, from womb to tomb. So it is for me [DM], and so it will be for you. My story, and yours, began when a man and a woman together contributed 20,000+ genes to an egg that became a unique person. Those genes contained the codes for the building blocks that, with astonishing precision, formed our bodies and predisposed our traits. My grandmother gave to my mother a rare hearing-
Along with my parents’ nature, I also received their nurture. Like you, I was born into a particular culture, with its own way of viewing the world. My values have been shaped by a family culture filled with talking and laughter, by a religious culture that speaks of love and justice, and by an academic culture that encourages critical thinking (asking, What do you mean? How do you know?).
We are formed by our genes, and by our contexts, so our stories will differ. But in many ways we are each like nearly everyone else on Earth. Being human, you and I have a need to belong. My mental video library, which began after age 4, is filled with scenes of social attachment. Over time, my attachments to parents loosened as peer friendships grew. After lacking confidence to date in high school, I fell in love with a college classmate and married at age 20. Natural selection disposes us to survive and pass on our genes. Sure enough, two years later a child entered our lives, and I experienced a new form of love that surprised me with its intensity.
But life is marked by change. That child now lives 2000 miles away, and one of his two siblings calls South Africa her home. The tight rubber bands linking parent and child have loosened, as yours likely have as well.
Change also marks most vocational lives. I spent my teen years working in the family insurance agency, then became a premed chemistry major and a hospital aide. After discarding my half-
Stability also marks our development. When I look in the mirror I do not see the person I once was, but I feel like the person I have always been. I am the same person who, as a late teen, played basketball and discovered love. A half-
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We experience a continuous self, but that self morphs through stages—
Across the life span, we grow from newborn to toddler to teen to mature adult. At each stage of life there are physical, cognitive, and social milestones. Let’s begin by exploring three key themes in developmental psychology.