Fear of positive evaluation and social affiliation in social anxiety disorder and major depression.

Fear of positive evaluation (FPE) is posited as a core feature of social anxiety disorder (SAD); however, little is known about its role in interpersonal functioning. We examined relationships between FPE and responses to a standardized social affiliation paradigm designed to facilitate positive social connection with an unacquainted conversation partner (trained confederate). The sample included adults with SAD (N = 52), major depressive disorder (MDD; N = 23), comorbid SAD and MDD (N = 36), and non-psychiatric controls (N = 33). Participants completed measures assessing FPE, affect, safety behaviors, and desire for future interaction. Confederates and observers rated participant behavior and their own desire for future interaction. FPE was most elevated in the SAD and comorbid groups, followed by the MDD group, and then non-psychiatric controls. In the full sample, FPE was associated with greater self-reported anxiety and safety behavior use, lower self-reported positive affect and desire for future interaction, lower observer-rated desire for future interaction and approach behaviors, and greater observer-rated anxious behaviors. Within-group correlations revealed that associations were weaker in the SAD only and comorbid groups (cf. control and MDD only groups); however, post-hoc moderation analyses indicated that the relationships between FPE and the outcomes of interest largely held across varying levels of social anxiety and depression severity. Findings underscore the potential role of FPE as a transdiagnostic factor relevant to understanding interpersonal functioning in social anxiety and depression.

Exaggerated amygdala activation to ambiguous facial expressions is a familial vulnerability factor for posttraumatic stress disorder.

OBJECTIVE: Previous research has reported hyperresponsivity in the amygdala and hyporesponsivity in ventral portions of the medial prefrontal cortex to threat-related stimuli in posttraumatic stress disorder (PTSD). Whether such findings generalize to more ambiguous stimuli and whether such brain activation abnormalities reflect familial vulnerabilities, trauma-exposure, or acquired characteristics of PTSD remain unclear. In this study, we measured brain responses to emotionally ambiguous stimuli (i.e., surprised facial expressions) in identical twin pairs discordant for trauma exposure to elucidate the origin of brain activation abnormalities. METHODS: Participants with PTSD (n = 12) and their trauma-unexposed identical cotwins (n = 12), as well as trauma-exposed participants without PTSD (n = 15) and their trauma-unexposed identical cotwins (n = 15), passively viewed surprised and neutral facial expressions during functional magnetic resonance imaging (fMRI). Afterward, participants labeled and rated each facial expression on valence and arousal. RESULTS: Amygdala activation to Surprised and Neutral facial expressions (versus Fixation) was greater in the participants with PTSD and their trauma-unexposed identical cotwins without PTSD, compared to the control twin pairs. In contrast, medial frontal gyrus (MFG) activation to Surprised facial expressions (versus Fixation) was diminished in the PTSD group relative to the other three groups. CONCLUSIONS: Amygdala hyperresponsivity to emotionally ambiguous facial expressions may be a familial vulnerability factor that increases the likelihood of developing PTSD after experiencing a traumatic event. In contrast, MFG hyporesponsivity may be an acquired characteristic of the disorder.