SEX DISCRIMINATION MENSTRUAL CYCLE: COMPARATIVE STUDY IN CHIMPANZEES & RHESUS

点击翻译按钮获取中文摘要

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Fluctuations of ovarian hormones across the menstrual cycle influence a variety of social and cognitive behaviors in primates. In this study, we examined whether menstrual cyclicity influences face perception in macaques and chimpanzees. We tested four female rhesus monkeys across one menstrual cycle and two female chimpanzees across three cycles. Menstrual phase was determined from analysis of ovarian hormone levels in monkeys, and from anogenital swelling in chimpanzees. Animals were tested 5 days a week on two face-tasks involving neutral portraits of male and female rhesus monkeys, chimpanzees and humans. In the visual preference task (VP), subjects had to touch a button to view a face image. The image remained on the screen as long as the button was touched, and the duration of pressing was taken as an index of looking time at the face stimulus. In the Face-Delayed Recognition Span Test, subjects were rewarded for touching the new face in an increasing number of serially presented faces. We found that female rhesus monkeys looked longer at faces of male rhesus monkeys during the peri-ovulatory period of the cycle in the VP. Such effects were absent for faces of other species. Heightened interest for stimuli of significant reproductive relevance during periods of high conception risk may help guide social and sexual behavior in the rhesus monkey. Similar effects were absent in the chimpanzee, a species closer to humans, consistent with the hypothesis of greater independence of behavior from neuroendocrine contro