Reactivity to dopaminergic drugs and aggression related personality traits

Abstract

In a double-blind cross-over experiment the personality dependent effects of a dopamine (DA) antagonist (haloperidol) and a DA precursor (L-dopa) on vigilance, psychomotor performance, and subjective activation was investigated in 24 healthy male volunteers divided according to questionnaire scores into high and low aggressives or high and low scorers of the sensation seeking subscales. Correlations and analyses of variance were performed on drug induced change scores. It was concluded that the personality score of aggressiveness as well as boredom susceptibility as one of the aspects of aggression seemed to be related to a reduction of performance and increase in tension by L-dopa and either no effect or an increase in stability of performance by haloperidol. In high thrill and adventure seeking (TAS) subjects a similar resistance to effects of haloperidol became evident in body temperature which remained unchanged whereas it was decreased in low TAS subjects. It was concluded that aggressiveness and its subaspects are related to lower sensitivity of DA receptors pointing to a biological DA related dimension ranging from aggression in the normal population to schizophrenia.