Personality and male-female influences on the EEG alpha rhythm.

The amplitude and frequency of the alpha rhythm was measured in electroencephalic recordings from 45 male and 46 female university students. The mean alpha frequency of the female group was significantly greater than the male group. There was no significant difference in alpha frequency between females in the first half of the menstrual cycle and those in the second half. The relationship between questionnaire measures of psychoticism, extraversion and neuroticism, and the alpha rhythm was investigated using analysis of variance, correlation analysis and factor analysis. Alpha amplitude was significantly greater in extraverted subjects, alpha amplitude and extraversion scores were significantly correlated and both had high loadings on a single factor. No relationship between psychoticism or neuroticism and alpha frequency or amplitude was observed.