Frontal reactivity and sensation seeking an ERP study in skydivers

1. In the line of Zuckerman's studies on sensation seeking and optimal level of arousal, the authors hypothesized that high sensation seeking might be used to compensate for anhedonia due to basal arousal deficit. A population of interest was found with parachutists practicing skydiving, generally described as very high sensation seekers. 2. After clinical assessment of emotional and affective components, amplitudes of the frontal P3 of the ERP were used as indices of arousal. 3. Skydivers presented more negative symptoms (anhedonia and blunted-affect) than controls. This was observed in isolation from any depressive episode, which would suggest the presence of emotional deficit as a trait. As expected, skydivers presented more sensation seeking than controls. These two results taken together could indicate that sensation seeking is an adaptive reaction to anhedonia. 4. ERP results showed that frontal P3 amplitudes were larger in skydivers than in controls, whereas in a previous study we showed the opposite in depressed patients with a similar emotional deficit. This could indicate that the frontal P3 amplitude does not reflect the emotional deficit per se. We suggest that it rather reflects the capacity to use some behaviors which improve automatic attentional processes in order to obtain arousing stimulation that could counterbalance the emotional deficit. Depressions with emotional deficit might be due to the lack of such a capacity.