Schizophrenic feature recognition deficits are independent of task criterion

The present study determined the minimal exposure time (i.e., critical stimulus duration (CSD) necessary for feature registration and recognition by normals and chronic schizophrenics. Our interest was whether the longer exposure times required by schizophrenics than by normals could be attributed to an inability of schizophrenics to maintain attention when the task criteria were stringent as opposed to 'loose'. The present findings support previous findings of impaired feature recognition by chronic schizophrenics. Chronic schizophrenics' and normals' CSDs were not affected by task criterion. The consistent performance by these groups on the 'loose' and 'rigid' task criteria suggest that if attentional lapses occur then they are as likely to occur for chronic schizophrenics as for normals and they are independent of the task's criterion. It is concluded that impaired feature registration for chronic schizophrenics is a consequence of a deficit at the earliest stage of encoding.