2010 年 81 巻 4 号 p. 381-387
The cost and probability bias in social situations are considered to be a maintaining factor for social anxiety disorder (SAD) symptoms. However, the process by which the cost and probability bias influences other SAD symptoms, such as avoidance behavior, self-perception of autonomic responses, and anxiety in social situations has not been investigated. We developed a model of the cost and probability bias and investigated the process through which the cost and probability bias influences SAD symptoms. Undergraduate students (N=290) were administered self-report measures assessing each component of SAD symptoms. A path analysis was conducted using the cost and probability bias model, which indicated high validity for the model (goodness of fit index=.99, adjusted goodness of fit index=.92, root mean square error of approximation=.09). The results also indicated that the cost bias had a strong effect on each component of SAD symptoms, and that the probability bias mediated the relationship between fear of negative evaluation and the cost bias. These findings suggest that changing the cost and probability bias may improve SAD symptoms.