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Developmental Psychology 101: Development in Infancy


The Developmental Psychology 101 series addresses the theories, periods, and implications of development in a human life from conception all the way through to the stage of adolescence. Developmental psychology is a field which is studied by psychology students and academic researchers; its purpose is to understand individuals based on the biological and psychological changes they experience throughout their lifespan. Development is defined as modifications that momentarily or permanently change an organism in the journey from conception to death (Cole et al., 2005). This 101 series of articles will refer to development from a psychological perspective, discussing its social, emotional, cognitive, and physical areas. Moreover, the debate of nature versus nurture will be discussed in the development of the following four stages of life: prenatal period, infancy, childhood, and adolescence.

The Developmental Psychology 101 series is divided into six chapters:

1. Developmental Psychology 101: Theories of Development

2. Developmental Psychology 101: Methods of Studying Development

3. Developmental Psychology 101: Prenatal Development and Birth

4. Developmental Psychology 101: Development in Infancy

5. Developmental Psychology 101: Development in Childhood

6. Developmental Psychology 101: Development in Adolescence

Developmental Psychology 101: Development in Infancy

Infancy is the period of life that begins as the result of pushing in birth and continues through the process of learning and adapting until the age of two. The transition between fetal life and infancy is made by what some call the trauma of birth (Rank, 1924) and others the miracle of life. The fetus’ relationship with the environment dramatically changes the minute its little body is outside in the world, inhaling oxygen, getting adjusted to the light, being cold, and feeling a caregiver’s touch. Many changes occur during this stage of life, most of which revolve around cognitive and motoric development. The theories discussed in the first article of this 101 series will be used during this article to further explain what happens in human infancy. This article strives to explain why in infancy nature is the primary factor that facilitates development. The arguments and conclusions presented are based on the research of many scientists and theories with a focus on Jean Piaget, a psychologist known for his work with children; Sigmund Freud, the founder of psychoanalysis; and Erik Erikson, a developmental psychologist and psychoanalyst.

White woman with brown hair in a red dress lying on a single bed with a naked baby on her chest surrounded by a group of people