title: Self-recognition deficits in schizophrenia patients with auditory hallucinations: a meta-analysis of the literature.
abstract: Theories about auditory hallucinations in schizophrenia suggest that these experiences occur because patients fail to recognize thoughts and mental events as self-generated. Different theoretical models have been proposed about the cognitive mechanisms underlying auditory hallucinations. Regardless of the cognitive model being tested, however, experimental designs are almost identical in that they require a judgment regarding whether an action was self-originated or not. The aim of the current study was to integrate all available literature for a meta-analysis on this topic and reach conclusions about self-recognition performance in (1) patients with schizophrenia compared with healthy controls and (2) patients with auditory hallucinations compared with patients without these symptoms. A comprehensive literature review identified 23 studies that contrasted the performance of schizophrenia patients with healthy controls (1370 participants) and 9 studies that directly compared patients with and without auditory hallucinations (315 participants). We found significantly reduced self-recognition performance in schizophrenia patients, which was more pronounced in patients with auditory hallucinations compared with patients without. In patients with hallucinations, this pattern of performance was specific to self-recognition processes and not to the recognition of new external information. A striking finding was the homogeneity in results across studies regardless of the action modality, timing delay, and design used to measure self-recognition. In summary, this review of studies from the last 30 years substantiates the view that self-recognition is impaired in patients with schizophrenia and particularly those with auditory hallucinations. This suggests an association, perhaps a causal one, between such deficit and hallucinatory experiences in schizophrenia.
authors.affiliation: Centre for Clinical Research in Neuropsychiatry, Graylands Hospital, Mail Bag No 1, Claremont, Perth, 6910, Australia. Flavie.Waters@health.wa.gov.au
authors.forename: Flavie
authors.initials: F
authors.lastname: Waters
authors.forename: Todd
authors.initials: T
authors.lastname: Woodward
authors.forename: Paul
authors.initials: P
authors.lastname: Allen
authors.forename: Andre
authors.initials: A
authors.lastname: Aleman
authors.forename: Iris
authors.initials: I
authors.lastname: Sommer
mesh_terms: D016022:Case-Control Studies; D003072:Cognition Disorders / Q000209:etiology / Q000503:physiopathology*; D006212:Hallucinations / Q000209:etiology / Q000503:physiopathology*; D006801:Humans; D012559:Schizophrenia / Q000150:complications / Q000503:physiopathology*; D012649:Self Concept