Neurobehavioral deficits in young adult offspring with heightened risk for psychosis who developed schizophrenia-spectrum disorder.

Neurobehavioral deficits in neuromotor function, verbal memory, executive function and attention found in patients with schizophrenia and their relatives have been suggested to be liability indicators or predictors of schizophrenia. It remains uncertain which of these neurobehavioral deficits are components of the illness itself or characteristics associated with genetic risk for it. The purpose of this study was to investigate the relation between these neurobehavioral deficits and schizophrenia-spectrum disorder in young adults at genetic risk for psychosis. A 93%-effective follow-up (total n=166, mean 22.4 yr of age) of a sample longitudinally investigated since fetal age provided complete data for mental disturbance, neuropsychological performance and neurological abnormality for 74 offspring at increased risk for psychosis (38 offspring of mothers with schizophrenia and 36 offspring of mothers with affective psychosis) and 88 normal-risk offspring. Abnormal glabella reflex and deficits in verbal memory, attention and complex executive functions seem specifically to be related to schizophrenia-spectrum disorder (primarily Cluster A personality disorders) among offspring at genetic risk for psychosis, while neurobehavioral deficits in general characterized offspring at heightened (vs. normal) genetic risk for psychosis, with no relation to schizophrenia-spectrum disorders. The two patterns of neurobehavioral deficits observed here may possibly reflect different causes and different aspects of a deviant neurodevelopmental process, and potentially contribute to a more nuanced version of this all-pervasive (but often non-specific) "model" of schizophrenia's development.