Background: Sustained attention has been found to be impaired in individuals suffering from schizophrenia and their close relatives. This has led to the hypothesis that impaired sustained attention is an indicator of vulnerability to schizophrenia.
Methods: The Edinburgh High Risk Study used the Continuous Performance Test-Identical Pairs version (CPT-IP) to assess sustained attention in 127 high risk participants, 30 controls and 15 first-episode schizophrenic patients. A second assessment was completed by 59 high risk and 18 control participants 18 months to 2 years after the first.
Results: No differences in attentional capacity were found between the high risk and control groups and there was no association between genetic liability to schizophrenia and poor performance on the CPT-IP. Additionally, no association between occurrence of psychotic symptoms in the high risk group and impaired attentional capacity was found.
Conclusions: The results suggest that deficits in sustained attention are not indicative of a genetic vulnerability to schizophrenia, and are not associated with the occurrence of psychotic symptoms.