RT Journal Article
SR Electronic
T1 Genetic Influences on Sociability: Heightened Amygdala Reactivity and Event-Related Responses to Positive Social Stimuli in Williams Syndrome
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 1132
OP 1139
DO 10.1523/JNEUROSCI.5324-08.2009
VO 29
IS 4
A1 Brian W. Haas
A1 Debra Mills
A1 Anna Yam
A1 Fumiko Hoeft
A1 Ursula Bellugi
A1 Allan Reiss
YR 2009
UL http://www.jneurosci.org/content/29/4/1132.abstract
AB Williams syndrome (WS) is a genetic disorder caused by a hemizygous microdeletion on chromosome 7q11.23. WS is associated with a compelling neurocognitive profile characterized by relative deficits in visuospatial function, relative strengths in face and language processing, and enhanced drive toward social engagement. We used a combined functional magnetic resonance imaging (fMRI) and event-related potential (ERP) approach to examine the neural basis of social responsiveness in WS participants to two types of social stimuli, negative (fearful) and positive (happy) emotional facial expressions. Here, we report a double dissociation consistent across both methods such that WS participants exhibited heightened amygdala reactivity to positive (happy) social stimuli and absent or attenuated amygdala reactivity to negative (fearful) social stimuli, compared with controls. The fMRI findings indicate that atypical social processing in WS may be rooted in altered development of disparate amygdalar nuclei that subserve different social functions. The ERP findings suggest that abnormal amygdala reactivity in WS may possibly function to increase attention to and encoding of happy expressions and to decrease arousal to fearful expressions. This study provides the first evidence that the genetic deletion associated with WS influences the function of the amygdala to be particularly responsive to socially appetitive stimuli.