The effect of peer contact upon physiological response to maternal separation

The response of both human and nonhuman primate infants to separation from their mothers is characterized by agitation or protest behaviors followed by a behavioral depressive reaction. In monkeys, this behavioral syndrome has striking physiological correlates, including heart rate and sleep disturbances. There is, however, considerable individual variability in response to maternal separation. The authors hypothesized that the amount of contact with particular, familiar conspecifics might account for some of this variability. In support of this notion, data are presented that indicate that pigtailed monkey infants who have been separated from their mothers but who maintain relatively high levels of peer contact do not show as severe decreases in heart rate during maternal separation as do those that exhibit less peer contact.