II. Hypersociability in Williams Syndrome

TLDR

Studying abnormal populations, such as Williams syndrome, offers a unique chance to link cognition, genotype, and brain neurobiology, but requires clear phenotypic delineation. The study investigates Williams syndrome to link genotype, brain, and cognition, focusing on its distinctive overfriendly social phenotype to lay groundwork for gene‑brain‑behavior analyses. Four studies examined hypersocial behavior across infants, toddlers, school‑age children, and adults with Williams syndrome. Excessively social behavior is a key phenotype distinguishing Williams syndrome, consistently appearing across ages and experimental paradigms.

Abstract

Abstract Studies of abnormal populations provide a rare opportunity for examining relationships between cognition, genotype and brain neurobiology, permitting comparisons across these different levels of analysis. In our studies, we investigate individuals with a rare, genetically based disorder called Williams syndrome (WMS) to draw links among these levels. A critical component of such a cross-domain undertaking is the clear delineation of the phenotype of the disorder in question. Of special interest in this paper is a relatively unexplored unusual social phenotype in WMS that includes an overfriendly and engaging personality. Four studies measuring distinct aspects of hypersocial behavior in WMS are presented, each probing specific aspects in WMS infants, toddlers, school age children, and adults. The abnormal profile of excessively social behavior represents an important component of the phenotype that may distinguish WMS from other developmental disorders. Furthermore, the studies show that the profile is observed across a wide range of ages, and emerges consistently across multiple experimental paradigms. These studies of hypersocial behavior in WMS promise to provide the ground-work for crossdisciplinary analyses of gene-brain-behavior relationships.