Compared comprehension of novel communicative signs to assist 2.5- and 3-year-old humans, chimpanzees, and orangutans find hidden objects during a hiding-finding game. Found that children at both ages performed above chance with all signs. No ape performed above chance for any signs not known before the experiment despite three times as many…

Addressing methodological limitations, Study One compared parent-child interactions of normal and language-delayed children; Study Two investigated whether mothers adjust the length of their utterances to the child's ability to comprehend or to produce language; Study Three probed interactional variables associated with variations in the…

Communication between parents and staff was observed in 16 proprietary day care centers during morning and afternoon transition times when parents dropped off children and picked them up. Results revealed large, stable differences among centers in the frequency and usefulness of these exchanges. About two-thirds of transition time opportunities…

Relationships between the function and content of maternal interventions to control their toddlers' behavior and behavior problems and compliance in the child's fifth year were studied. Naturalistic observation of 51 dyads consisting of depressed and nondepressed mothers and their children who were 1.5 to 3.5 years old at the time of first…