Cognitive performance and Heart rate variability: The influence of menstrual cycle in young subjects

Menstrual cycle characterized by various dynamic alterations in sex steroidal hormones notonly alters the reproductive organs but also various systemic organs and hence higher functions are oneamong them. This study is an attempt to determine the influence of various hormones on cognitive functionusing short term heart rate variability analysis in different phases of menstrual cycle.Materials and Methods: Thirty participants were subjected for the baseline recording of HRV andpsychomotor vigilance test and short term memory test along with HRV recording in three subsequentnumbers of times to study variations in three different phases of menstrual cycle . Both time domainand frequency domain parameters were studied during resting state and while performing psychomotorvigilance test and short term memory test.Results: The time domain and frequency domain parameters on comparison with resting state to duringpsychomotor vigilance test and short term memory test parameters were statistically insignificant in allthree phases recorded. Unlikely on comparison of heart rate variability parameters both times domainand frequency domain values of RRI, RMSSD and LF (nu) values were statistically significant across thedifferent phases suggesting upper hand of sympathetic tone.Conclusion: The present study indicated increased sympathetic discharge during follicular phase oncomparison to luteal and menstrual phase. The results also indicated a change in cognitive functioningduring different phases due to hormonal variations.Keywords: Menstrual cycle, Heart rate variability, Psychomotor vigilance test.