Extraversion, neuroticism and the four temperaments of antiquity: an investigation of physiological reactivity

The present study adopted an historical perspective, which highlighted the place of Pavlovʹs work on the four classical temperaments in current theory and research on personality. Drawing on the work of Pavlov and the later contribution of [Robinson (1996). Brain, mind, and behavior: a new perspective on human nature. Westport, C.T.: Praeger Publishers] it was hypothesised that differences in cerebral reactivity contrast the sanguine (low reactivity) and melancholic (high reactivity) temperaments. The EPQ was used to identify four extreme groups of female subjects corresponding to the classical temperaments: ES/sanguine (n=16), EN/choleric (n=16), IS phlegmatic (n=8) and IN/melancholic (n=16). Reactivity indices included P1N1 and N1P2 response components of the vertex evoked potential to three different tone intensities and three different light flash intensities. Using extraversion and neuroticism as between subject factors and intensity as a repeated measures factor, separate analyses of variance for each dependent variable revealed no significant personality related effects. In comparison, planned contrasts between the ES and IN groups revealed a number of significant differences in the auditory modality but no significant differences in the visual modality. In accord with prediction, the IN group exhibited significantly steeper auditory P1N1 and N1P2 amplitude intensity functions than the ES group. Also in accord with prediction, the IN group exhibited higher overall auditory P1N1 and N1P2 amplitudes, however, only the P1N1 difference was significant. It was argued that auditory evoked potential amplitude provides a more appropriate index of cerebral reactivity than visual evoked potential amplitude.