The menstrual cycle from a bio-behavioral approach: a comparison of oral contraceptive and non-contraceptive users.
The purpose of the present study was to clarify the effects of the menstrual cycle on: (1) accuracy and simple reaction time in a problem-solving situation; (2) academic performance; (3) identify corresponding cyclic changes in a set of psychophysiological measures during rest/test conditions; and (4) to compare oral contraceptive with non-oral contraceptive users. Eight volunteer females, 4 normally cyclic and 4 oral contraceptive users, reported once weekly throughout two menstrual cycles during which changes in blood pressure, heart rate, skin temperature, finger pulse amplitude, and verbal reaction time were monitored. Differences in verbal reaction time were found between oral contraceptive users and non-users over phases of the cycle, the users being significantly slower during menstrual and premenstrual phases. It was also observed that all subjects reacted slower in the menstrual and ovulatory phases during cycle one, although no differences were found during cycle two. Skin temperature changes between groups occurred during the postovulatory phase of cycle two, the control group having shown a much greater increase than oral contraceptive users. These results indicated a suppressive influence of oral contraceptives which appeared to affect cognitive rather than motor responses, and that these effects were residual when no pills were taken menstrually and premenstrually. Also indicated was the finding that although a 28-day cycle of menstrual events exists, periodicity of these events may be reflected in a much larger cycle non-currently defined.
D000124:Achievement; D000293:Adolescent; D000328:Adult; D001519:Behavior / Q000502:physiology*; D001794:Blood Pressure; D003276:Contraceptives, Oral; D005260:Female; D006339:Heart Rate; D006801:Humans; D008598:Menstruation; D011340:Problem Solving / Q000502:physiology; D011674:Pulse; D011930:Reaction Time / Q000502:physiology; D012881:Skin Temperature
D003276:Contraceptives, Oral