Auditory hallucinations in dissociative identity disorder and schizophrenia with and without a childhood trauma history: similarities and differences.

Little is known about similarities and differences in voice hearing in schizophrenia and dissociative identity disorder (DID) and the role of child maltreatment and dissociation. This study examined various aspects of voice hearing, along with childhood maltreatment and pathological dissociation in 3 samples: schizophrenia without child maltreatment (n = 18), schizophrenia with child maltreatment (n = 16), and DID (n = 29). Compared with the schizophrenia groups, the DID sample was more likely to have voices starting before 18, hear more than 2 voices, have both child and adult voices and experience tactile and visual hallucinations. The 3 groups were similar in that voice content was incongruent with mood and the location was more likely internal than external. Pathological dissociation predicted several aspects of voice hearing and appears an important variable in voice hearing, at least where maltreatment is present.