Anxiety Disorders: Skuse D

Skuse D. · Behavioural and Brain Sciences Unit, Institute of Child Health, University College London, 30 Guilford Street, London WCIN 1EH, UK. · Philos Trans R Soc Lond B Biol Sci. · Pubmed #17118928 links to  free full text

Abstract: The neural basis of social cognition has been the subject of intensive research in both human and non-human primates. Exciting, provocative and yet consistent findings are emerging. A major focus of interest is the role of efferent and afferent connectivity between the amygdala and the neocortical brain regions, now believed to be critical for the processing of social and emotional perceptions. One possible component is a subcortical neural pathway, which permits rapid and preconscious processing of potentially threatening stimuli, and it leads from the retina to the superior colliculus, to the pulvinar nucleus of the thalamus and then to the amygdala. This pathway is activated by direct eye contact, one of many classes of potential threat, and may be particularly responsive to the 'whites of the eyes'. In humans, autonomic arousal evoked by this stimulus is associated with the activity in specific cortical regions concerned with processing visual information from faces. The integrated functioning of these pathways is modulated by one or more X-linked genes, yet to be identified. The emotional responsiveness of the amygdala, and its associated circuits, to social threat is also influenced by functional polymorphisms in the promoter of the serotonin transporter gene. We still do not have a clear account of how specific allelic variation, in candidate genes, increases susceptibility to developmental disorders, such as autism, or psychiatric conditions, such as anxiety or depressive illness. However, the regulation of emotional responsiveness to social cues lies at the heart of the problem, and recent research indicates that we may be nearing a deeper and more comprehensive understanding.

Corden B, Chilvers R, Skuse D. · Behavioural and Brain Sciences Unit, Institute of Child Health, University College London WC1N 1EH, UK. · Neuropsychologia. · Pubmed #17920642 No free full text.

Abstract: We combined eye-tracking technology with a test of facial affect recognition and a measure of self-reported social anxiety in order to explore the aetiology of social-perceptual deficits in Asperger's syndrome (AS). Compared to controls matched for age, IQ and visual-perceptual ability, we found a group of AS adults was impaired in their recognition of fearful and sad expressions and spent significantly less time fixating the eye region of all faces. For AS subjects, but not controls, the extent of the failure to fixate the eyes predicted the degree of impairment at recognising fearful expressions. In addition, poor fear recognition and reduced fixation of the eyes were independently associated with greater levels of social anxiety in AS individuals. These findings support the hypothesis that avoidance of emotionally arousing stimuli, such as eyes, contributes to social-perceptual impairment in AS. Furthermore, our findings are consistent with theories implicating amygdala-mediated over-arousal and anxiety in the development of these social-perceptual deficits.