Fear and disgust processing during repeated exposure to threat-relevant stimuli in spider phobia.

Although disgust plays a significant role in the etiology of spider phobia, there remains a paucity of research examining the role of disgust in the treatment of spider phobia. Spider fearful participants (N = 46) were randomly assigned to a disgust (view vomit images) or neutral activation (view inanimate objects) condition. They were then repeatedly exposed to a videotaped tarantula, during which time their fear, disgust, and physiological levels were assessed repeatedly. Growth curve analyses indicated that repeated exposure led to significant declines in fear and disgust with no statistically significant differences between the two conditions. However, there was marginal evidence for decreased physiological arousal during repeated exposure among spider fearful participants in the disgust activation condition compared to those in the neutral condition. Reduction in disgust during exposure in the disgust activation condition remained significant after controlling for change in fear, whereas change in fear was no longer significant after controlling for change in disgust. However, the opposite pattern of relations between change in fear and disgust was observed in the neutral activation condition. Higher fear and disgust activation during exposure was also associated with higher fear and disgust responding on a subsequent behavioral task and higher spider fear and disgust at 3-month follow-up. Baseline trait disgust propensity also predicted fear and disgust parameters during repeated exposure. The implications of these findings for the role of disgust in the treatment of spider phobia are discussed.