UC Irvine

Background. Emotions have long been discussed in conjunction with the autonomic nervous system. Most research on heart-mood linkages does not consider sex differences or an evident underlying mechanism for sex differences- sex hormone levels. Further, most research is limited to cross-sectional and laboratory studies. The degree to which affect-autonomic associations manifest in everyday life may be different and may vary by sex and, for women, by menstrual cycle phase. This study employs ambulatory monitoring of cardiovascular measures (e.g., heart rate and heart rate variability; HRV) and concurrent emotions (e.g., sadness, stress, anxiety, anger, and happiness) in everyday life to better characterize affect-autonomic associations as a function of sex and menstrual cycle phase. Methods. Participants (N = 174) were monitored over a 5-day observation period (one 2-day and one 3-day session), using an ambulatory 24-hour electrocardiogram to monitor heart rate and ecological momentary assessment to record emotions every approximately 30 minutes. Women were monitored in both the early to mid-follicular and -luteal phases of their menstrual cycles and men in two comparably distanced sessions. Results. Multilevel models indicated that for both sexes, negative emotions and happiness were associated with elevated heart rate. Relative to men, women exhibited elevated heart rate and reduced HRV during reports of anger. For women, during the luteal phase, momentary reports of sadness, stress, and anxiety were found to predict increased heart rate and reduced HRV. Conclusion. These findings demonstrate the importance of considering sex and menstrual cycle phase in research investigating heart-mood linkages.