title: Quantitative psychomotor dysfunction in schizophrenia: a loss of drive, impaired movement execution or both?
abstract: OBJECTIVE
  The aim of the present study was to investigate the predictive value of qualitative psychomotor performance levels and subaspects of the negative syndrome for quantitative motor activity levels in patients with schizophrenia.
  
  
  METHODS
  Twenty-seven stabilized patients with schizophrenia and 22 age- and sex-matched healthy controls were included in the study. An extensive battery of psychomotor performance tests (Finger Tapping Test, Purdue Pegboard Test, Line Copying Test, Neurological Evaluation Scale, Salpêtrière Retardation Rating Scale), clinical rating scales (Positive and Negative Syndrome Scale) and 24-hour actigraphy were administered to all participants.
  
  
  RESULTS
  Correlational analyses showed that motor activity levels were associated with avolition as well as clinically assessed psychomotor slowing. However, in a regression model, only avolition was found to be a significant predictor for motor activity levels in patients with schizophrenia; none of the psychomotor performance tests nor the severity of emotional expressivity deficits contributed to the model.
  
  
  CONCLUSIONS
  Qualitative and quantitative psychomotor deficits seem to be independent phenomena in stabilized patients with schizophrenia. The diminishing in motor activity in patients with schizophrenia is related to a loss of drive and not to problems in the quality of movement execution.
authors.affiliation: Collaborative Antwerp Psychiatric Research Institute, University of Antwerp, Antwerp, Belgium.
authors.forename: Lise
authors.initials: L
authors.lastname: Docx
authors.forename: Bernard
authors.initials: B
authors.lastname: Sabbe
authors.forename: Pieter
authors.initials: P
authors.lastname: Provinciael
authors.forename: Niel
authors.initials: N
authors.lastname: Merckx
authors.forename: Manuel
authors.initials: M
authors.lastname: Morrens
mesh_terms: D056044:Actigraphy; D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects / Q000494:pharmacology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D009483:Neuropsychological Tests; D011597:Psychomotor Performance / Q000187:drug effects; D012559:Schizophrenia / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D014836:Volition / Q000187:drug effects; D055815:Young Adult
chemical_list: D014150:Antipsychotic Agents