Spontaneous autonomic activity as related to psychopathy

Spontaneous fluctuations and levels in skin conductance and finger pulse volume recordings were studied in criminal subjects during three experimental periods, before, during and after a series of auditory stimuli, and related to psychopathy as estimated by scores in the Gough delinquency scale (De). The sample was subdivided into two groups, containing subjects with scores above (HD) and below (LD) the median in the De scale. Analyses of variance yielded significant group x period interaction effects for skin conductance fluctuation and level measures. The more psychopathic group (HD) had a lower number of skin conductance fluctuations in stimulation and post-stimulation periods, and had lower levels, decreasing over periods. No differences were obtained in the pulse volume measurements. The lower skin conductance reactivity in the more psychopathic subjects was discussed in terms of lower cortical arousal, and the implications for the interpretation of skin conductance fluctuations were analysed.