Journal of Cognitive Psychotherapy: An International Quarterly Volume 24, Number 3 ' 2010 Probability and Cost Biases in Social Phobia: Nature, Specificity, and Relationship to Treatment Outcome Elizabeth A. Nelson, MA James J. Lickel, MS Jennifer T.Sy, MS Laura J. Dixon, BA Brett J. Deacon, PhD University of Wyoming, Laramie Social phobia is maintained in part by cognitive biases concerning the probability and cost of negative social events. More specifically, individuals with social phobia tend to believe that negative social events are extremely likely to occur, and that if such events were to happen, the consequences would be awful or unbearable. The aim of the present review is to critically evaluate research on the nature and specificity of probability and cost biases in social phobia. Changes in probability and cost estimates during treatment and their relationship to treatment outcome are detailed. The review concludes with a discussion of how current cognitive behav- ioral interventions target these biases. Directions for future research are proposed. Keywords: social phobia; cognitive biases; cognitive behavioral treatment; review T heoretical models of social phobia (e.g., Glark 8c Wells, 1995; Rapee 8c Heimberg, 1997) emphasize the importance of biased cognitive processing in the development and main- tenance of anxiety disorders. Indeed, it is thought that most fears are driven by faulty appraisals concerning the expectation or anticipation of potential future harm (e.g.. Beck, Emery, 8c Greenberg, 1985). Garr (1974) proposed that these perceptions of threat are composed of esti- mates of the probability of the event (i.e., the likelihood a given event will occur) and the cost of the event (i.e., the negative consequences associated with the event). Several theorists (e.g.. Beck,. 1976; Rapee 8c Heimberg, 1997) have identified mechanisms by which probability and cost biases may exert their influence. Social phobia is characterized by social fears—concerns about social embarrassment, humiliation, and subsequent rejection by others (American Psychiatric Association, 2000). Beck ( 1976) suggested that cognitive biases exac- erbate and perpetuate these social fears via biased processing of social information. Specifically, overestimates of the probability and cost of negative social events result in the perception of social situations as dangerous. As a result, individuals with such fears tend to be hypervigilant to cues of social rejection. Individuals with social phobia often attend to internal cues that may elicit social disapproval (e.g., sweating, blushing), thereby resulting in a failure to encode information from © 2010 Springer Publishing Company 213 DOI: 10.1891/0889-8391.24.3.213