Background: The developmental disorder Williams syndrome (WS) is characterised by a distinctive cognitive profile and an intriguing social phenotype. Individuals with the disorder are often highly social engaging with familiar and unfamiliar people and once in an interaction they often show subtle abnormalities of social behaviour. Atypically…

Background: Self-injurious behaviour is a chronic condition among people with intellectual and developmental disabilities for which there is no known cure. The pain hypothesis suggests that individuals who engage in self-injury have altered or diminished pain perception. The purpose of the present study was to assess how frequently individuals…