DELAYED OBJECT PERMANENCE DEVELOPMENT IN PRENATALLY STRESSED RHESUS-MONKEY INFANTS (MACACA-MULATTA)

This prospective study investigated the effects of mild maternal stress during pregnancy on object permanence performance in rhesus monkey infants (Macaca mulatta). Beginning on day 45 postpartum, 24 rhesus monkey infants were tested four times per week on a series of tests examining Piagetian object permanence. Twelve infants were derived from females exposed to a daily 10-minute mild stressor during the midgestational period of pregnancy, while 12 were derived from females undisturbed during pregnancy. Prenatally stressed infants took longer to recover an object that was partially obstructed or observed to vanish from view, suggesting that prenatally stressed infants may be cognitively impaired. Implications of the findings for occupational therapy practice are discussed.