Kyra, a 16-year-old girl, is severely underweight but thinks that she is too fat. She exercises daily for 3 hours and cuts her food into very small pieces while eating. She has not gotten her periods for the last 6 months. She is usually depressed and sounds confused. In this scenario, Kyra is most likely to be diagnosed with

At 6 months of age, American infants sleep about 14 hours a day, whereas infants who are the same age in Kenya sleep about 12 hours a day, and infants in the Netherlands sleep about 16 hours a day. This variation is best described by ____

a. reflexive responses b. cultural practice c. innate preprogramming d. biological influence

A child's ability to make connections between new words and referents so rapidly that he or she cannot be considering all possible meanings for the new word is referred to as

a. overregularization. c. overextension. b. underextension. d. fast mapping.