Developmental psychology is the study of how people grow and change. These changes traditionally looked at how people's thoughts, feelings, behaviours and physical bodies changed and grew in childhood and adolescence.
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Life span development is the study of how humans grow and change throughout their entire life. The term lifespan development refers to age-related changes that occur from birth, throughout a persons' life, into and during old age.
The 6 Stages of lifespan development are :
Infancy
Birth-two years. While the infant is dependent on adults for most things, many psychological characteristics are rapidly developing. During this stage, the bond that develops between the infant and their primary caregiver is important in terms of the infant's later emotional development.
Childhood
Two-ten years. During this stage, children become increasingly independent from their parents as they learn to do things themselves and gain more self-control. During this stage, children's cognitive skills develop and they also begin to develop an understanding of what is right and wrong.
Adolescence
Ten-twenty years. The onset of puberty marks the beginning of adolescence. It is dominated by seeking independence from parents and developing one's own identity. Compared to the child, an adolescent's thought processes are more logical, complex and idealistic.
Early Adulthood
Twenty-forty years. This is the stage of establishing personal and financial independence and establishing and consolidating a career. For many, it is also the time in which individuals select a partner, develop an ongoing intimate relationship and begin a family.
Middle Age
Forty-sixty five years. This is a period of expanding social and personal involvements and responsibilities, advancing a career, and supporting offspring in their development to becoming mature individuals.
Older Age
Sixty five years plus. A period of considerable adjustment to changes in one's life and self-perceptions. For many older people, this is a very liberating time when they no longer have the day-to-day responsibility of looking after their children or working.