Personality factors moderate subjective and psychophysiological responses to d-amphetamine in humans

The aim of the present study was to examine the relationship between measures of novelty and sensation seeking and both psychophysiological and subjective measures of stimulation after a pharmacological challenge with an indirect dopamine agonist, ct-amphetamine. Prepulse inhibition (PPI) of the startle reflex and subjective responses were assessed after the challenge. The results indicated that the Novelty Seeking scale of the Tridimensional Personality Questionnaire (TPQ; M. Zuckerman, 1994). TPQ was a significant predictor of lower PPI and greater subjective stimulation. The Disinhibition scale of the Sensation Seeking Scale (SSS; M. Zuckerman, S. B. G. Eysenck, Br M. J. Eysenck, 1978) moderated the effects of amphetamine on stimulation and elation, whereas the Boredom Susceptibility and Experience Seeking subscales of the SSS moderated subjective stimulation. These findings indicate that higher scores on novelty and sensation seeking correspond to heightened sensitivity to the effects of a stimulant medication.