Disgust and Fear Related UCS-expectancy Bias in Blood Fearful individuals

People with specific fears tend to overestimate the occurrence of unpleasant consequences in situations involving their feared objects. Such expectancy bias logically acts in a way to confirm phobic fear and avoidance. Increasing evidence suggests that blood phobia is qualitatively different from other specific phobias. Confrontation with phobic stimuli gives rise to disgust and repulsion rather than (threat-induced) fear. Therefore, this study examined the role of disgust-related UCS expectancies following confrontation with blood phobia-relevant stimuli. Using a thought-experiment procedure, high (n = 30) and low (n = 30) blood-fearful individuals estimated the probability that the presentation of slides showing a bloody wound and a series of filler slides would be followed by a sip of nauseating juice, a threat-related electrical shock or nothing. Although participants generally expected shock and juice following blood, UCS expectancies for both aversive outcomes for blood were significantly more pronounced in high blood-fearful participants. This implicates that UCS-expectancy biases may be involved in the development and maintenance of blood phobia.