| This research examined differences in the neuropsychology and autonomic response between participants with social phobia (SP), comorbid social phobia and major depressive disorder (CM), and asymptomatic control participants (AC) under baseline and stressor conditions. Participants were 33 undergraduates aged 18 to 41 (M = 20.45, SD = 4.40) who were recruited from the University of Oregon. Neuropsychological tests and autonomic response were assessed during baseline and stressor conditions, during which participants believes they were being videotaped as part of a training film. Study materials included the Trail Making Test, Digit Span, Spatial Span, and Wisconsin Card Sorting Test; salivary cortisol samples; periodic recordings of EDA and HR; semi-structured interviews; and questionnaires assessing state/trait anxiety, social anxiety, depression, and overall psychiatric symptomatology. Overall, non-specific fluctuations in EDA showed a significant stress effect for all groups, demonstrating the efficacy of the stressor. As predicted, pre-baseline assessment of CM showed higher HR than SP and AC, who did not differ. SP, however, showed significant HR elevations to the levels of CM during stress, and both SP and CM were elevated compared to controls post-stress. Neuropsychological findings indicated that Spatial Span scores were worse for SP during stress, improved for AC, and showed no change for CM. Furthermore, while TMT A times improved for all groups under stress, the TMT B times showed an interaction effect, with completion time improving significantly less for SP than for AC and CM. Analyses of the normative data for WCST total errors indicated that AC and CM improved significantly during stress, while SP performance was worse during the stressor than baseline condition. In summary, although the stressor appeared to cause some neuropsychological and autonomic changes for all groups, SP showed decreased performance during stress on several measures related to working memory (TMT B and WCST), and on spatial attention (Spatial Span), but not verbal attention (Digit Span) or visuomotor speed (Trails A). SP showed decreased performance during stress compared to CM, although the two did not differ on symptom scores or autonomic measures during stress. Implications of these findings for diagnostic classification, treatment, and future research are discussed. |
