Affective imagery and the startle response: probing mechanisms of modulation during pleasant scenes, personal experiences, and discrete negative emotions.

Two experiments addressed the following issues concerning modulation of the acoustic startle reflex during emotional imagery: (1) Is startle inhibited or potentiated during imagery of pleasurable events? (2) Does startle modulation differ for personal versus standard imagery scenes? (3) Is startle modulated differently during anger versus fear? For standard scenes, startle was greater during aversive than pleasant imagery, with both exceeding neutral. Blink potentiation was greater during imagery of personal pleasant than nonpersonal pleasant scenes. Startle potentiation did not differ for anger versus fear material, but differences were found in self-report, corrugator EMG, and HR response. These results suggest that in addition to the emotional valence of imagined material, startle reactivity is influenced by the degree of engagement or active disengagement from the sensory environment. The findings also indicate that fear and anger are differentiable in terms of affective report, cardiac mobilization, and expressive behavior, but not at the primary motivational level at which reflex priming occurs.