Early detection of imminent psychosis allows for the possibility of interventions to prevent onset, or to minimise severity and disability. It also has potential to enhance knowledge of the factors important in the etiology of psychotic illnesses. Neurocognitive deficits are well documented in psychotic illnesses and there is evidence to suggest that such deficits are present in individuals long before they develop the illness. Further, it has been proposed that such impairments may indicate an underlying predisposition to develop psychosis and may thus be described as ‘vulnerability indicators’. This study aimed to investigate the proposed vulnerability indicator of impaired sustained attention in young people thought to be at ultra high-risk of developing psychosis imminently to see whether it would improve the prediction of psychosis in this group. The Continuous Performance Test – Identical Pairs (CPT-IP) version performance of an ultra high-risk group (UHR, N = 70) was compared with that of a healthy comparison group (NC, N = 51) and a first-episode psychosis group (FEP, N = 32). The UHR group exhibited performance deficits compared to the NC group and performed at a level similar to that of the FEP group. However, within the UHR group, those who developed psychosis within the timeframe of the study did not differ from those who did not develop psychosis on their CPT-IP performance. These results support sustained attention as an indicator of vulnerability to psychosis, but suggest that CPT-IP performance does not help to predict transition to psychosis in an ultra high-risk group.
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