Cognitive NeuroscienceTowards the neural basis for hypersociability in a genetic syndromeBellugi, Ursula1,3; Adolphs, Ralph2; Cassady, Cindi1; Chiles, Michael1Author Information 1Laboratory for Cognitive Neuroscience, The Salk Institute for Biological Studies, 10010 N. Torrey Pines Road, La Jolla, CA 92037, USA 2Department of Neurology, Division of Cognitive Neuroscience, University of Iowa, Iowa City, IA, USA CACorresponding Author: Ursula Bellugi ACKNOWLEDGEMENTS: This research was supported by grants to U.B. from NIH (P01 HD33113, P50 NS22343, PO1DC01289), the OakTree Philanthropic Foundation, and the James S. McDonnell Foundation; as well as from a Sloan Research Fellowship to R.A. The authors thank the national and regional Williams Syndrome Associations and are grateful to the subjects and their families for participation in these studies. Received 17 March 1999; accepted 30 March 1999 NeuroReport: June 3rd, 1999 - Volume 10 - Issue 8 - p 1653-1657 Buy Abstract WILLIAMS syndrome (WMS), a rare disorder with a distinctive profile of medical, psychological, neurophysiological and neuroanatomical characteristics, results from hemizygous deletion of about 20 genes. The phenotype exhibits specific dissociations in higher cognitive functions: general cognitive deficits but spared linguistic abilities; extreme spatial cognitive deficits, but intact face processing. Of special interest is an unusual social phenotype in WMS: an overly friendly, engaging personality and excessive sociability with strangers. In this first experimental study of social behavior in WMS, we report that WMS subjects show an abnormal positive bias in their social judgments of unfamiliar individuals, consistent with their behavior in real life. Our findings contribute to an understanding of the neural and genetic bases of human social behavior. © 1999 Lippincott Williams & Wilkins, Inc.