Bilateral asymmetry of skin conductance orienting activity and levels in schizophrenics

Abstract

Skin conductance orienting response characteristics and levels were examined bilaterally in groups of schizophrenics with and without orienting responses, termed responders and non-responders, and in a normal control group. A reduction or absence of responses was observed in institutionalised responders in the direction of fewer responses on the left hand. Marked bilateral differences in levels occurred in both responder and non-responder groups but in opposite directions - higher on the right hand in the responder group and higher on the left in the non-responder group. These differences were not found in the control group. In all groups bilateral differences in response amplitudes, and recovery times occurred whereas response latencies and incidence of spontaneous fluctuations did not differ bilaterally. Group differences in skin conductance levels, spontaneous fluctuation frequencies, and orienting response characteristics, including amplitude, latency and recovery time, as well as habituation characteristics of response amplitudes and levels were observed in support of results published previously. In particular skin conductance levels and spontaneous fluctuation frequencies were significantly higher in responder groups than non-responders indicating higher arousal levels in the responder groups. The results were interpreted as evidence of temporal-limbic dysfunction in schizophrenia. The reduced orienting responsivity on the left in institutionalised schizophrenics may be associated with left hemisphere pathology. It is suggested that the opposite directions of asymmetry of levels in the responder and non-responder groups are associated with extreme states of arousal which may arise from a disorder of limbic functioning.