Effect of stimulus type and worry on physiological response to fear.

The current study investigated whether the immediacy and concreteness of fear stimuli play an important role in the effects of trait worry on physiological response to fear. One hundred and eight participants were exposed to one of three fear-provoking stimuli: an actual spider (immediate and concrete), an opaque box which they were told contained a spider (immediate but abstract), or a recorded script (distant and abstract). Participants were yoked by levels of worry and gender. Heart rate, vagal tone, and skin conductance were recorded. The combination of high worry and an actual spider caused the largest decrease in vagal tone, but both the actual spider and opaque box increased skin conductance regardless of worry level. The results suggest that factors, such as the type of fear stimulus and the type of physiological measures used, are vital in understanding the reasons for and the limits of fear activation.