The effect of distraction on focal attention in paranoid and non-paranoid schizophrenic patients compared to normals and non-psychotic psychiatric patients.

Previous research comparing the performance of schizophrenics and normals in neutral and distractor conditions has indicated that schizophrenics are more vulnerable to distraction. The present study was designed to clarify whether schizophrenics are more distractible than normals and non-psychotic psychiatric patients when the distractor conditions are matched with the neutral conditions for discriminating power and to determine whether paranoid and non-paranoid paranoid schizophrenics, eight non-psychotic psychiatric patients, and 20 normals were tested using neutral and distractor digit-span tests. The results do not support the hypothesis of a differential deviation in all schizophrenics with respect to distractibility. However, significant differences were found between paranoid and non-paranoid schizophrenics; the paranoid, in contrast to the non-paranoid schizophrenics, did not appear to be vulnerable to distraction under the conditions of this experiment.