A neuropsychological investigation into 'Theory of Mind' and enhanced risk of schizophrenia.

Theory of Mind (ToM) is the ability to correctly determine the intentions and behaviours of others. It is known that this capability is compromised in individuals with schizophrenia. It is has not been fully elucidated whether this observed phenomenon is of a state or trait nature. This study investigated whether ToM impairments could be linked to schizophrenia liability. A battery of ToM tests (the Hinting Task, a Self-Monitoring drawing task and cartoon picture stories) were used to compare healthy controls (n=13) with relatives of individuals with schizophrenia who had experienced psychotic symptoms (HR+, n=12) and those relatives who had not (HR-, n=13). All participants belonged to the Edinburgh High Risk Study. Significant group differences were seen on the Self-Monitoring and cartoon tasks for the HR+ group, particularly those who had experienced symptoms at or around the time of testing. The observed ToM deficits measured by this battery of ToM tasks appeared to be related to state effects rather than enhanced risk of schizophrenia.