Deficits of the automatic orienting of attention in schizophrenic patients.

The automatic orienting of attention was studied in medicated non-psychotic schizophrenic patients and in matched controls using the Posner paradigm of covert orienting to peripheral cues. This paradigm allows determination of the "benefits" in performance when attention is moved in advance to target location ("valid" trials) and the "costs" in performance when attention has to be reoriented to target location after an incorrect directional cue ("invalid" trials). Compared to normals, schizophrenics showed reduced costs of invalid cueing and increased benefits of valid directional cueing. Schizophrenics did not show selective visual field asymmetries reported in similar studies. The decreased inhibition in the presence of incorrect directional cues may be related to a reduced tone of monoaminergic terminals possibly involved in the regulation of selective attention and arousal regulation.