The Relationship of Extraversion and Neuroticism to the Eeg

Abstract
In a recent series of investigations significant but conflicting relationships have been claimed between the two personality dimensions extraversion (E) and neuroticism (N) and certain spontaneous and induced features of the normal EEG. Savage (1964), using alpha abundance data from automatic frequency analysis, demonstrated a significant positive correlation between extraversion and high alpha amplitude. Extraversion has been similarly related to the amplitude of the averaged evoked potential waveform (Shagass and Schwartz, 1965). However, in an investigation by Broadhurst and Glass (1969) both alpha amplitude and prevalence bore an inverse relationship to E scores; extraversion was significantly associated with the rate of change of potential of the EEG, as was neuroticism with the alpha frequency. More recently, Winteret al. (1971) could find no direct relationship between extraversion and EEG amplitude, though there was a tendency for low amplitude activity to be associated with high neuroticism scores. The findings were interpreted as showing a significant interaction between the variables measured, the relationship of extraversion and amplitude varying according to the neuroticism score.