Fearfulness and startle potentiation during aversive visual stimuli.

Recent experimental research suggests an association between negative affect and potentiation of the human startle reflex, as well as enhancement of this effect among fearful compared to low fear subjects. In the present study, 32 undergraduates were selected for high or low total Fear Survey Schedule scores. Acoustic startle probes were presented while subjects received warned presentations of aversive and neutral photographic slides. High fear but not low fear subjects showed potentiated short-latency cardiac acceleration and blink magnitude, and reduced blink latency, during aversive compared to neutral slides. These results support the hypothesis that affective modulation of startle is enhanced among high fear compared to low fear subjects. Considered in the context of prior findings, the results suggest that this individual difference effect generalizes across psychophysiological components of the startle reflex and diverse procedures for manipulating affect.