Sex differences observed in a study of EEG of linguistic activity and resting-state: Exploring optimal EEG channel configurations

Abstract

This study reports the differences observed in the EEG signals of linguistic activity and resting-state between male and female subjects in a population of 16 individuals (8 females and 8 males). These differences were spotted while performing two experiments: sex identification and subject identification, where the initial aim was to identify the optimal number and placement of EEG channels to obtain high accuracies in sex and subject identification. The results of the identification show that the signals analyzed contain sex-specific information and that the best features from this sex-specific information are extracted from different EEG channel locations and from different hemispheres of the brain, for either sex. The effect of the number of electrodes and electrode localization is seen with clear differences between male and female subjects. The accuracy loss for sex identification when reducing the number of channels from 14 to 1 was of only 0.03 points during resting states (Accuracies from 0.79 to 0.76). For subject identification within either male or female groups during resting states, the accuracy loss was larger when reducing the number of channels from 14 to 1 (0.96 to 0.71 for female, 0.96 to 0.81 for male subjects). One finding of this study is that Theta and Gamma bands are strongest for males in the right hemisphere during resting states, whereas during linguistic activity these bands exhibit similar strengths in the left hemisphere for both males and females. Similar specific features in brain signals may enable the design of a flexible EEG device that can be adapted to specific mental tasks and Subject settings.