UBC Theses and Dissertations
Actual and perceived mood fluctuations : a comparison of menstrual, weekday, and lunar cycles McFarlane, Jessica
The major purpose of the study was to examine mood fluctuations associated with phases of the menstrual cycle. To assess the relative impact of the menstrual cycle on moods, other cycles hypothesized to influence moods also were assessed. Mood fluctuations in women and men were studied both prospectively and retrospectively to determine whether cyclic changes occur with the phases of the menstrual cycle, lunar cycle, and/or days of the week. Each participant (15 women using oral contraceptives, 12 normally cycling women, and 15 men) recorded their moods daily for 70 days (prospective data). A daily mean score was obtained for both pleasantness and arousal (each on a 9-point positive to negative scale). Mood stability/variability was recorded daily on a 4-point scale. At the end of the study, participants recalled (retrospective data) their mood over the previous 2 months for each day of the week and the phases of their menstrual cycle (women only). The focus on menstrual cycles was sucessfully camouflaged. Prospectively, there were no group differences and no menstrually-related mood fluctuations. The retrospective reports, however, indicated systematic bias. Women recalled more positive moods in the follicular phase and more negative moods in the premenstrual and menstrual phases than they had reported prospectively. All groups reported weekday mood changes — Monday lows and Friday/Saturday highs. Recollections of weekday mood fluctuations were similar to but more exaggerated than prospective reports. Prospective reports revealed no mood fluctuations over the lunar cycle. Together, these results indicate that stereotypes (both well- and ill-founded) influence recollections of mood, and are consistent with schematic processing theories. The importance for menstrual cycle research of obtaining information about positive as well as negative experiences, camouflaging the purpose of the study, collecting prospective data, and assessing results in the contexts of other cycles also is discussed.