title: Cognition and autonomic function in schizophrenia: inferior cognitive test performance in electrodermal and niacin skin flush non-responders.
abstract: BACKGROUND
  Patients with schizophrenia suffer from a broad range of cognitive disturbances. The impact in terms of functional outcome is significant. There are also several reports of disturbed autonomic regulation in the disease. The present study examined cognitive function as well as psychophysiological parameters in patients with schizophrenia and healthy controls.
  
  
  METHODS
  Twenty-five patients and 14 controls were investigated with electrodermal activity (EDA), an oral niacin skin flush test and a comprehensive neurocognitive test program including the Wechsler battery (WAIS-R), Fingertapping Test, Trail Making Test, Verbal Fluency, Benton Visual Retention Test, Wisconsin Card Sorting Test and Rey Auditory Verbal Learning Test.
  
  
  RESULTS
  The patients generally had inferior test results compared to controls. Further analysis revealed that the EDA non-responding patient group explained this variation with significant lower test results than controls. On executive tests, EDA non-responders also performed significantly worse than EDA responding patients. The small group of niacin non-responding patients exhibited an even lower overall test performance. Delayed niacin flush also correlated inversely with psychomotor function and IQ in the patients.
  
  
  CONCLUSIONS
  The findings support the hypothesis of a neurodevelopment disturbance affecting both autonomic function and higher cortical function in schizophrenia.
authors.affiliation: Department of Neuroscience, Psychiatry, Uppsala University, SE-751 85 Uppsala, Sweden. Electronic address: bjorn.nilsson@neuro.uu.se.
authors.forename: B M
authors.initials: BM
authors.lastname: Nilsson
authors.affiliation: Department of Neuroscience, Psychiatry, Uppsala University, SE-751 85 Uppsala, Sweden.
authors.forename: G
authors.initials: G
authors.lastname: Holm
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institute, SE-17177 Stockholm, Sweden.
authors.forename: C M
authors.initials: CM
authors.lastname: Hultman
authors.affiliation: Department of Neuroscience, Psychiatry, Uppsala University, SE-751 85 Uppsala, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Ekselius
mesh_terms: D000328:Adult; D003071:Cognition; D003072:Cognition Disorders / Q000503:physiopathology / Q000523:psychology*; D005260:Female; D005712:Galvanic Skin Response; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D009525:Niacin; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D013548:Sweden; D014665:Vasodilator Agents
chemical_list: D014665:Vasodilator Agents; D009525:Niacin
keywords: Autonomic function; Cognition; Electrodermal activity; Niacin flush; Psychophysiology; Schizophrenia