Reduced range of sensory sensitivity in chronic nonparanoid schizophrenics.

Used a forced-choice auditory signal-detection method to test the hypothesis that, compared to acute paranoid schizophrenics, chronic nonparanoid schizophrenics would show a restricted range of sensitivity to environmental cues. 40 male chronic nonparanoid and paranoid schizophrenics served as Ss. Ability to detect the presence of an auditory cue, while concurrently tracking a visual stimulus, was measured under 2 conditions, auditory monitoring being given primary or secondary importance. In this task, a narrowed range of sensitivity implies a greater deficit in ability to detect the auditory cue when the primary focus is placed elsewhere. This deficit was significantly greater in the chronics in both initial and replication experiments. The function of restricted sensitivity in limiting the range of both relevant and distracting stimuli that are responded to by chronic nonparanoid schizophrenics is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)