Analysis of EEG Changes during Different Phases of Menstrual Cycle in Adult Females

ANALYSIS OF EEG CHANGES DURING DIFFERENT PHASES OF MENSTRUAL CYCLE IN ADULT FEMALES DR. SUDIPTA PATNAIK, DR. RAJAT MOHANTY S. C. B. MEDICAL COLLEGE, CUTTACK Female life cycle is associated with a number of hormonal milestones like menarche, adolescent, reproductive and menopausal period. All these events and interventions alter the levels of sex hormones and may cause a change in the activity of the brain and EEG at large. Every woman undergoes major hormonal changes in hormone, body temperature, and metabolic rate, characterize the menstrual cycle of female subject. This study was carried out from 25th January 2014 to 24th April 2016 at S. C. B. Medicalcollege, Cuttack to study the Electroencephalographical changes and power spectral analysis during different phases of menstrual cycle. The subjects in the present study were 10 female students in the age group of 25-35 years, having regular menstrual cycle for 28 days. The effects of neurohormonal status on the EEG Alpha activity were studied in 10 women (25-35 years old) during different cycles. The psychometric and electroencephalographic (EEG) indices of waves, basal body temperature, and salivary progesterone level were monitored every two or three days. The menstrual and follicular recording sessions occurred before the basal temperature rise caused by ovulation, the luteal recording session occurred after the increase in progesterone level by more than 20 % compared to the day before, and the premenstrual recording sessions occurred after the decrease in progesterone level by more than 20 % compared to the day before. The EEG, electromyographic (EMG) and electrocardiographic (ECG) characteristics of cognitive efficiency and psycho-emotional tension were recorded at rest and during task performance. The experiments were started in the menstrual phase in half the subjects and in the luteal phase in the other half. Psychometric characteristics, EEG Alpha activity, EMG and ECG indices were compared for all the five phases at rest and in response to cognitive task performance. The results have shown that all psychometric and EEG indices are menstrual-cycle-dependent. The maximum cognitive fluency, peak frequency, band width, and power in the 2 frequency band are observed in the luteal phase, while the maximum power in the low-frequency 1 band, as well as visual and cognitive activation calculated from power reduction, are observed in the follicular phase of the menstrual cycle. The hypothesis that EEG Alpha activity depends on the neurohormonal status is supported by the positive correlation of salivary progesterone level with the peak frequency and the power in the 2 band and its negative correlation with the power in the 1 band. It is concluded that psycho-physiological recording sessions in women must be carried out with due consideration of the menstrual cycle phase. Estradiol, Alpha frequency, Center frequency, EEG, Neurohormonal.