Personality, event-related potential (ERP) and heart rate (HR): An investigation of Gray's theory

Abstract

Following Gray's theory of personality, the aim of the study was to examine the role of the personality dimensions, behavioural inhibition and activation, in mediating event-related potentials (ERPs) and the level of anticipatory heart rate (HR) deceleration response during two visual-stimulus recognition tasks. In the first task ERPs and anticipatory HR changes were elicited by feedback words informing the subjects about the quality of their response (‘correct’, ‘incorrect’). In the second task ERPs and HR responses were elicited from 62 women by feedback words (‘losing’, ‘winning’) indicating losing or winning, of amounts of money. The Gray-Wilson Personality Questionnaire (GWPQ), the Eysenck Personality Questionnaire (EPQ) and the I 7 questionnaire were used to measure variables which refer to the function of the activation and inhibition system. The N200, P300, N400, P650 and N800 peak amplitudes of the ERPs and the level of anticipatory HR deceleration response to the feedback signals were measured. Personality and physiological responses were first analysed by using a split-plot ANOVA design and second by examining multiple relationships with factor analysis. Separate ANOVAs were performed across Ss selected from the total group ( n = 62) on the basis of extreme scores (high or low) on Approach (APPR), Passive Avoidance (PASS.AV), Extinction (EXTI), Extraversion (E), Neuroticism (N) and Impulsiveness (I). In line with Gray's prediction, high APPR Ss exhibited larger P600 peak amplitudes to signals indicating winning and low APPR Ss exhibited larger P600 amplitudes to signals indicating losing. Neurotic Ss produced larger N800 peak amplitudes to stimuli indicating losing as compared with stimuli indicating winning. Stable Ss, in contrast, did not display differences between feedback stimuli. Heart-rate deceleration response to feedback signals was successful in distinguishing high and low N Ss as well as Introverts and Extraverts. Neurotic Ss, compared with Stable ones, showed a more pronounced anticipatory HR slowing for both of the feedback signals. Introverts displayed more pronounced HR decelerations for punishment compared with reward signals. Extraverts, in contrast, showed greater HR decelerations for reward compared with punishment signals. These results were all in line with predictions that can be derived from Gray's theory. However, in the opposite direction was the relationship between PASS.AV and N200 peak: High PASS.AV Ss displayed greater N200 peak amplitudes to winning signals compared with signals indicating a correct response. Results from factor analysis gave rise to a three-factor solution wherein personality dimensions sensitive to signals of reward and that sensitive to signals of punishment were loading together with different physiological factors.