The cardiac responses of schizophrenics to orienting, signal and non-signal tones

Abstract

The cardiac responses of schizophrenics were examined under three conditions: (1) to repeated 75 dB, 1000 Hz (orienting) tones of no attentional significance; (2) to 75 dB, 1000 and 2000 Hz tones presented randomly and requiring a motor response to the 1000 Hz (signal) tone; (3) to 85 dB, 1000 Hz orienting tones. Responses of non-psychotic psychiatric patients were examined to the 75 dB tones. All patients were subdivided upon the basis of electrodermal responsivity during conditions (1) and (3), into groups of responders — no habituation of responses ; non-responders — no responses ; habituators — responses habituated to criterion. All groups exhibited a decelerative response with a latency of less than 1 sec. The groups were differentiated by the second component of the response to the orienting tones: responders — acceleration; habituators — deceleration; non-responders — predominantly no response. All exhibited accelerative responses to the signal tones. Parallels between cardiac and electrodermal responsivity are outlined.