title: Head movements during conversational speech in patients with schizophrenia.
abstract: BACKGROUND
  Motor abnormalities are frequently described in schizophrenia, and work by Altorfer and colleagues suggests that measuring head movements during conversational speech shows differences at the level of the individual. We wished to see whether their findings, conducted using computer analysis of video obtained in motion capture suites, could be replicated using compact, portable movement sensors, in a case-control study comparing the mean amplitude of head movements during general conversation.
  
  
  METHODS
  A referred sample of inpatients and outpatients with a diagnosis of paranoid schizophrenia was identified from case note information. Movement sensors, mounted in a baseball cap worn by subjects, transmitted data via Bluetooth to a laptop, which simultaneously captured audio to identify who was speaking. Subjects also completed a series of rating scales.
  
  
  RESULTS
  Data from the final 11 cases and 11 controls demonstrated a substantial group difference in mean amplitude of head movement velocity during speech (p < 0.0001), although this was not significant at the level of the individual.
  
  
  CONCLUSIONS
  Movement sensors proved well suited to capturing head movements, demonstrating a large effect size in subjects with schizophrenia.
authors: Division of Psychiatry, University of Nottingham, Institute of Mental Health, Triumph Road, Nottingham NG7 2TU, UK.
authors: Stuart John
authors: SJ
authors: Leask
authors: Bert
authors: B
authors: Park
authors: Priya
authors: P
authors: Khana
authors: Ben
authors: B
authors: Dimambro
keywords: Accelerometer; conversation; movement; psychosis; schizophrenia; speech
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