BIS، BAS، و جانبداری: نقش شخصیت و حهت گیری شناختی در اضطراب اجتماعی

The goal of the present research was to test the hypothesis that cognitive biases for negative and threatening social information mediate the effects of behavioral inhibition system (BIS) and behavioral approach system (BAS) sensitivity on social anxiety. Participants completed self-report measures of BIS and BAS and then underwent a social-threat induction procedure in which they were told they would have to perform a speech. A battery of cognitive bias measures was then administered, followed by a battery of state anxiety measures. Audience members also rated participants’ anxiety during the speech. Structural equation modeling was used to test the hypothesized model. As predicted, the fully-mediated model showed the best fit to the data, and higher BIS and lower BAS were found to have significant indirect effects on social anxiety via cognitive bias.

Among the many models of social anxiety proposed, Kimbrel’s (2008) model of social anxiety is unique because it integrates a wide range of factors (i.e., personality, genetic, biological, environmental, cognitive) into a unified model. While research on this model has emerged in recent years (e.g., Kimbrel, Mitchell, & Nelson-Gray, 2010), many aspects of the model remain untested. The objective of the present research was to provide the first direct test of Kimbrel’s hypothesis that cognitive biases for negative and threatening social information mediate the effects of behavioral inhibition system (BIS) and behavioral approach system (BAS) sensitivity on social anxiety. 1.1. Reinforcement sensitivity theory Kimbrel’s model is based largely upon the revised reinforcement sensitivity theory of personality (rRST; Gray & McNaughton, 2000), which is a biologically-based model of personality. rRST proposes that individual differences in three major brain subsystems—the BIS, BAS, and, fight-flight-freeze system (FFFS)—are responsible for many of the individual differences observed in personality, psychopathology, and reinforcement sensitivity. The BAS is proposed to underlie reward-seeking behavior and impulsivity, whereas the FFFS is proposed to motivate avoidance and escape behaviors in response to conditioned and unconditioned aversive stimuli. In contrast, the primary task of the BIS is to resolve conflicts among competing goals (e.g., approach–avoidance conflicts). The BIS is proposed to accomplish this task by inhibiting behavior, increasing arousal, and assessing for risk. The BIS is also proposed to underlie the emotion of anxiety and the personality trait of neuroticism. Consistent with the position of Gray and McNaughton (2000) and contemporary research in this area (e.g., Tull, Gratz, Latzman, Kimbrel, & Lejuez, 2010), the current paper takes the position that existing self-report inventories of BIS and neuroticism assess combined BIS–FFFS sensitivity. Accordingly, the term “BIS–FFFS” is used throughout to refer to self-report measures of BIS based on earlier versions of the theory, whereas the terms “BIS” and “FFFS” refer to the neurobiological systems proposed by Gray. 1.2. BIS–FFFS and social anxiety The current paper also takes the position that social anxiety is a dimensional construct, and that this dimension is positively associated with BIS–FFFS functioning (e.g., Kimbrel, Cobb, Mitchell, Hundt, & Nelson-Gray, 2008). For example, Kimbrel et al. (2010) reported positive associations between continuous measures of BIS–FFFS and social anxiety across three samples of adults, and Hundt, Mitchell, Kimbrel, and Nelson-Gray (2010) reported BIS–FFFS predicted decreased romantic activities, decreased social activities, and fewer leadership roles among college students. In addition, imaging studies report increased regional cerebral blood flow in key components of the BIS and FFFS (e.g., amygdala, hippocampus) among social phobics during anticipation of a public-speaking task (Tillfors et al., 2001). 1.3. Cognitive bias and social anxiety Socially-anxious individuals often exhibit cognitive biases for negative social information (Kimbrel, 2008). For example, they tend to believe they will be negatively evaluated in social situations (Leary, Kowalski, & Campbell, 1988), expect more negative social events and fewer positive social events (Lucock & Salkovskis, 1988), and exhibit an attentional bias for threatening social information (Asmundson & Stein, 1994). Evidence regarding a memory bias among socially-anxious individuals has been more mixed. Breck and Smith (1983) reported a memory bias for negative social information among socially-anxious individuals using a free-recall task, but only when they thought they would have to interact with a stranger later on in the experiment. Similarly, Mansell and Clark (1999) reported individuals high on social anxiety recalled fewer positive self-referent words than individuals low on social anxiety when told they would have to give a speech prior to recall, but the bias did not occur when the social threat induction procedure was not used. In contrast, Rapee, McCallum, Melville, Ravenscroft, and Rodney (1994) did not employ a social threat induction procedure and failed to find a memory bias among individuals with social phobia across a variety of memory tasks. Together, these findings suggest memory biases for negative and social threatening information may only occur among socially-anxious individuals under conditions of imminent social threat (Kimbrel, 2008). 1.4. BIS and bias Building upon the work of Gray and McNaughton, 2000, Eysenck, 1997 and Kimbrel, 2008 proposed that the cognitive biases observed among socially-anxious individuals are the result of heightened BIS sensitivity. Specifically, because the BIS is proposed to engage in external and internal scanning for threat-relevant information in response to potentially threatening situations (Gray & McNaughton, 2000), Kimbrel proposed that the BIS is the personality/biological basis for many of the cognitive biases (e.g., memory bias, negative expectancies and beliefs, increased perception of threat) observed among socially-anxious individuals. Thus, cognitive biases for negative and threatening social information are proposed to mediate the effect of BIS on social anxiety under conditions of imminent social threat. While this model has not been tested directly, there is some indirect support for this proposal. For example, BIS–FFFS has been associated with a tendency to focus on negative information (Noguchi, Gohm, & Dalsky, 2006) and recall negatively-valenced words in a free-recall task (Gomez & Gomez, 2002). 1.5. BAS and social anxiety While Kimbrel’s model primarily focuses on the role of BIS, low BAS is also proposed to play a significant, albeit modest, role in social anxiety due to the interdependent nature of the BIS–FFFS and BAS systems. This proposal is based on Corr’s (2002) joint-subsystems hypothesis, which posits that the BIS and BAS have antagonistic and facilitatory effects upon behavior and are functionally interdependent. Kimbrel (2008) proposed that low BAS represents an additional risk factor for social anxiety, and there is some evidence to support this position (e.g., Kimbrel et al., 2010). 1.6. Objective and hypotheses The objective of the present research was to test whether cognitive biases for negative and threatening social information mediate the effects of BIS–FFFS and BAS on social anxiety. It was hypothesized that BIS–FFFS would be positively associated with negative cognitive bias and social anxiety, and that the effects of BIS–FFFS on social anxiety would be fully mediated by cognitive biases. BAS was predicted to be negatively associated with cognitive bias and social anxiety, and the effects of BAS on social anxiety were predicted to be mediated by cognitive biases as well. While no previous study has directly examined the relationship between BAS, bias, and social anxiety, the latter hypothesis is consistent with previous research demonstrating that decreased positive expectancies mediate the effect of low BAS on depression (Beevers & Meyer, 2002).