title: Dissociation mediates the relationship between childhood trauma and hallucination-proneness.
abstract: BACKGROUND
  It has been proposed that the relationship between childhood trauma and hallucinations can be explained by dissociative processes. The present study examined whether the effect of childhood trauma on hallucination-proneness is mediated by dissociative tendencies. In addition, the influence of dissociative symptoms on a cognitive process believed to underlie hallucinatory experiences (i.e. reality discrimination; the capacity to discriminate between internal and external cognitive events) was also investigated.
  
  
  METHODS
  Patients with schizophrenia spectrum disorders (n=45) and healthy controls (with no history of hallucinations; n=20) completed questionnaire measures of hallucination-proneness, dissociative tendencies and childhood trauma, as well as performing an auditory signal detection task.
  
  
  RESULTS
  Compared to both healthy and non-hallucinating clinical controls, hallucinating patients reported both significantly higher dissociative tendencies and childhood sexual abuse. Dissociation positively mediated the effect of childhood trauma on hallucination-proneness. This mediational role was particularly robust for sexual abuse over other types of trauma. Signal detection abnormalities were evident in hallucinating patients and patients with a history of hallucinations, but were not associated with pathological dissociative symptoms.
  
  
  CONCLUSIONS
  These results are consistent with dissociative accounts of the trauma-hallucinations link. Dissociation, however, does not affect reality discrimination. Future research should examine whether other cognitive processes associated with both dissociative states and hallucinations (e.g. deficits in cognitive inhibition) may explain the relationship between dissociation and hallucinatory experiences.
authors: School of Psychology, Bangor University, Bangor, Gwynedd, UK. Filippo.Varese@liverpool.ac.uk
authors: F
authors: F
authors: Varese
authors: E
authors: E
authors: Barkus
authors: R P
authors: RP
authors: Bentall
mesh_terms: D002648:Child; D002650:Child Abuse, Sexual / Q000523:psychology* / Q000706:statistics & numerical data; D004213:Dissociative Disorders / Q000523:psychology*; D005260:Female; D006212:Hallucinations / Q000523:psychology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data; D011594:Psychometrics; D012307:Risk Factors; D012559:Schizophrenia; D012565:Schizophrenic Psychology; D013315:Stress, Psychological / Q000523:psychology*; D011795:Surveys and Questionnaires; D013647:Task Performance and Analysis