Stimulus estimation and the overprediction of fear.

Overprediction of fear is the tendency to overestimate the amount of fear that one will experience in a subjectively threatening situation. Little is known about this bias, despite the important role it appears to play in producing phobic avoidance. The present study proposed a stimulus estimation hypothesis of overprediction, which states that overprediction of fear arises from the overprediction of the danger features of the feared stimulus and the underprediction of safety features. This model was supported by the results of structural equation modelling based on the responses of 224 snake-fearful subjects exposed to a live harmless snake. The determinants of the stimulus estimation bias are considered and directions for further investigation are discussed.