AUTONOMIC NERVOUS-SYSTEM MARKERS OF PSYCHOPATHOLOGY IN CHILDHOOD-ONSET SCHIZOPHRENIA

Background: Consistent abnormalities in peripheral indicators of auton omic activity, ie, skin conductance (SC) and heart rate (HR), have bee n reported in adult-onset schizophrenia. Herein, we use these markers to test the hypothesis of continuity between childhood-onset schizophr enia and adult-onset schizophrenia. Methods: Skin conductance and HR w ere recorded from 21 severely ill children and adolescents (mean age, 14.1 years) with childhood-onset (less than or equal to 12 years) schi zophrenia (patient group) and from 54 age-matched controls (control gr oup) during a rest period, a series of innocuous tones, reaction time insructions, and a simple warned reaction time task. Results: During r est, patients had higher rates of spontaneous SC responses (SCRs) and HRs than controls, but their SC level was marginally lower and decline d more slowly over time. Half of the patients, compared with 4% of the controls, failed to give SC-orienting responses to the first 2 tones. Patients who responded had impaired SCR magnitudes, and their habitua tion was more erratic than that of controls. The increase in SC level and SCR frequency at the onset of the task period was greatly attenuat ed in the patients, so that both variables were higher in controls. Pa tients bad smaller SCRs and anticipatory HR responses to the reaction time stimuli. Skin conductance nonresponding was associated with negat ive and total symptoms, and spontaneous SCR frequency was associated w ith positive symptoms. Conclusions: The findings show similar abnormal ities in autonomic nervous system activity in childhood-onset schizoph renia to those found in adult chronic schizophrenia, thus supporting t he hypothesis of continuity of the childhood and adult forms of the il lness. Comparisons with data from other childhood disorders suggest th at the combination of low-elicited SC activity with high levels of spo ntaneous SC activity may be specific to schizophrenia.