PSY-2210 Lecture Notes - Lecture 2: Habituation, Neuroimaging, Neural Tube
Document Summary
Psy 2210 chpt 4 physical development in infancy and toddlerhood. Body growth: changes in body size and muscle-fat makeup. By the end of the first year, a typical infant"s height is about 32in, more than fifty percent greater than at birth. By two years it is seventy-five percent greater. By five months, birth weight has doubled to about fifteen pounds. One year it has tripled to twenty-two pounds. By two years it has quadrupled to thirty pounds. In second year most toddlers slim down, which continues into middle childhood: individual and group differences. In infancy girls are slightly shorter and lighter than boys with higher ratio of fat to muscle. Smaller differences in the sexes persist throughout childhood and magnifies at adolescence. Ethnic differences in body size are apparent as well. Best estimate of a child"s physical maturity is skeletal age, a measure of bone development.