Reactivity of alpha rhythms to eyes opening (the Berger effect) during menstrual cycle phases

EEG and EMG responses to eyes open showed that magnitude of α-1 amplitude suppression corresponds to increasing EMG and salivary cortisol concentration only at the Follicular phase, when low alpha frequency waves are dominant in combination with low progesterone level. The magnitude of alpha suppression in response to eyes open in the upper α-2 frequency range does not vary with the menstrual cycle. The Luteal phase corresponds to the highest level of salivary progesterone and is associated with enhancement of the α-bandwidth. The most prominent reaction of salivary cortisol level, forehead EMG, and alpha EEG power to opening of the eyes occurs in the Follicular phase. This research reveals the dependence of the EEG Berger effect on the hormonal state and EEG alpha frequency.