title: Voice identity discrimination and hallucination-proneness in healthy young adults: a further challenge to the continuum model of psychosis?
abstract: BACKGROUND
  Auditory hallucinations occur in schizophrenia and also in the general population. However, evidence points to differences in the nature and the mechanisms of clinical and non-clinical hallucinations, challenging the dominant assumption that they represent the same phenomenon. The current study extended this evidence by examining voice identity perception in hallucination-prone individuals. In schizophrenia, deficiencies discriminating between real (external) voices have been linked to basic acoustic cues, but voice discrimination has not yet been investigated in non-clinical hallucinations.
  
  
  METHODS
  Using a task identical to that employed in patients, multidimensional scaling of voice dissimilarity judgements was used to examine how healthy individuals differing in hallucination-proneness (30 high and 30 low hallucination-prone individuals) distinguish pairs of unfamiliar voices. The resulting dimensions were interpreted with reference to acoustic measures relevant to voice identity.
  
  
  RESULTS
  A two-dimensional "voice space", defined by fundamental frequency (F0) and formant dispersion (Df), was derived for high and low hallucination-prone groups. There were no significant differences in speaker discrimination for high versus low hallucination-prone individuals on the basis of either F0 or Df.
  
  
  CONCLUSIONS
  These findings suggest voice identity perception is not impaired in healthy individuals predisposed to hallucinations, adding a further challenge to the continuum model of psychotic symptoms.
authors: a School of Psychology , University of Western Australia , 35 Stirling Hwy, Crawley , WA 6009 , Australia.
authors: Saruchi
authors: S
authors: Chhabra
authors: Johanna C
authors: JC
authors: Badcock
authors: Murray T
authors: MT
authors: Maybery
authors: Doris
authors: D
authors: Leung
mesh_terms: D000328:Adult; D001307:Auditory Perception; D003463:Cues; D005260:Female; D006212:Hallucinations / Q000209:etiology / Q000503:physiopathology*; D006801:Humans; D007062:Identification, Psychological; D008297:Male; D008875:Middle Aged; D008960:Models, Psychological; D011618:Psychotic Disorders / Q000150:complications / Q000503:physiopathology*; D012559:Schizophrenia / Q000150:complications / Q000503:physiopathology*; D014833:Voice Quality; D055815:Young Adult