Physiological responses in high-P subjects during active and passive coping

There have been relatively few studies of the psychophysiological correlates of Eysenck's dimension of psychoticism (P) and those which do not exist report findings which cannot be readily integrated to isolate a distinctive physiological basis of P. The present study investigated differences between subjects scoring high and low on the P scale of the Eysenck Personality Questionnaire (EPQ) in relation to sympathetic and parasympathetic arousal following aversive stimulation. An active-passive coping paradigm using an aversive tone was selected to elicit responses and cardiovascular measures (heart period, heart period variance, T-wave amplitude) and a skin conductance measure (event-related skin conductance) were obtained. The findings show that differences between high- and low-P subjects are specific to the coping condition. Under active coping, high-P subjects exhibited greater sympathetic arousal following the aversive tone than low-P subjects. There was no significant difference between the high-P and low-P subjects on any physiological variable under the passive coping condition. It is suggested that if there is differential functioning of the divisions of the autonomic nervous system in subjects differing in P, that these differences may only manifest themselves under specific situations.