Sustained and selective attention as measures of genetic liability to schizophrenia

We tested for a relationship between attention and genetic liability to sch izophrenia. Samples of probands with DSM-IV schizophrenia (n = 20), their w ell first-degree relatives (n = 40) and healthy controls (n = 82) were test ed using measures of sustained attention (degraded-stimulus continuous perf ormance test: DS-CPT) and selective attention (spatial negative priming tas k). Assuming a liability-threshold model, we predicted that probands would display greater attentional decrements than controls and that the relatives would show intermediate levels of decrement. We did not observe the predic ted pattern of effect using either measure, although the probands showed a trend towards less negative priming. However, our results may have been aff ected by self-selection bias in probands and relatives and clinical heterog eneity among probands, which could have reduced our power to detect effects . (C) 2001 Elsevier Science B.V. All rights reserved.