title: Individual differences in social behavior predict amygdala response to fearful facial expressions in Williams syndrome.
abstract: Williams syndrome (WS) is a genetic condition often paired with abnormal social functioning and behavior. In particular, those with WS are characterized as being relatively hypersocial, overly emotional/empathic, and socially uninhibited or fearless. In addition, WS is associated with abnormal amygdala structure and function. Very little is known however about the relationship between specific social behaviors and altered amygdala function in WS. This study was designed to compare three models that relate abnormal social behavior with amygdala function in WS (indiscriminate sociability, emotional and empathic sociability and social fearlessness). We used a social behavior assessment procedure (Salk Institute Sociability Questionnaire), functional magnetic resonance imaging and an implicit emotion face processing task to test these models. Our findings provide support for a model of abnormal social fearlessness by showing that in WS, abnormal amygdala response to fear is paired with an increased tendency to approach strangers. Specifically, individuals with WS that exhibited less amygdala response to fearful facial expressions (compared to neutral) also exhibited an increased tendency to approach strangers. These findings contribute to our understanding of social and emotional functioning in neurodevelopmental conditions and provide evidence that in WS, amygdala response to fear modulates social behavior.
authors.affiliation: Center for Interdisciplinary Brain Sciences Research (CIBSR), Stanford University School of Medicine, 401 Quarry Road, Stanford, Palo Alto, CA 94305-5795, USA. bhaas@stanford.edu
authors.forename: Brian W
authors.initials: BW
authors.lastname: Haas
authors.forename: Fumiko
authors.initials: F
authors.lastname: Hoeft
authors.forename: Yvonne M
authors.initials: YM
authors.lastname: Searcy
authors.forename: Debra
authors.initials: D
authors.lastname: Mills
authors.forename: Ursula
authors.initials: U
authors.lastname: Bellugi
authors.forename: Allan
authors.initials: A
authors.lastname: Reiss
mesh_terms: D000328:Adult; D000679:Amygdala / Q000503:physiopathology*; D005149:Facial Expression; D005239:Fear; D005260:Female; D006801:Humans; D008297:Male; D012919:Social Behavior; D012928:Social Desirability; D011795:Surveys and Questionnaires; D018980:Williams Syndrome / Q000503:physiopathology*