title: Interaction of language, auditory and memory brain networks in auditory verbal hallucinations.
abstract: Auditory verbal hallucinations (AVH) occur in psychotic disorders, but also as a symptom of other conditions and even in healthy people. Several current theories on the origin of AVH converge, with neuroimaging studies suggesting that the language, auditory and memory/limbic networks are of particular relevance. However, reconciliation of these theories with experimental evidence is missing. We review 50 studies investigating functional (EEG and fMRI) and anatomic (diffusion tensor imaging) connectivity in these networks, and explore the evidence supporting abnormal connectivity in these networks associated with AVH. We distinguish between functional connectivity during an actual hallucination experience (symptom capture) and functional connectivity during either the resting state or a task comparing individuals who hallucinate with those who do not (symptom association studies). Symptom capture studies clearly reveal a pattern of increased coupling among the auditory, language and striatal regions. Anatomical and symptom association functional studies suggest that the interhemispheric connectivity between posterior auditory regions may depend on the phase of illness, with increases in non-psychotic individuals and first episode patients and decreases in chronic patients. Leading hypotheses involving concepts as unstable memories, source monitoring, top-down attention, and hybrid models of hallucinations are supported in part by the published connectivity data, although several caveats and inconsistencies remain. Specifically, possible changes in fronto-temporal connectivity are still under debate. Precise hypotheses concerning the directionality of connections deduced from current theoretical approaches should be tested using experimental approaches that allow for discrimination of competing hypotheses.
authors.affiliation: Department of Neuroscience, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands. Electronic address: b.curcic@umcg.nl.
authors.forename: Branislava
authors.initials: B
authors.lastname: Ćurčić-Blake
authors.affiliation: University of California and Veterans Affairs Medical Center, San Francisco, United States.
authors.forename: Judith M
authors.initials: JM
authors.lastname: Ford
authors.affiliation: Translational Research Center, University Hospital of Psychiatry, University of Bern, Switzerland.
authors.forename: Daniela
authors.initials: D
authors.lastname: Hubl
authors.affiliation: Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom.
authors.forename: Natasza D
authors.initials: ND
authors.lastname: Orlov
authors.affiliation: Brain Center Rudolf Magnus, University Medical Center Utrecht, The Netherlands.
authors.forename: Iris E
authors.initials: IE
authors.lastname: Sommer
authors.affiliation: Graylands Hospital, North Metro Health Service Mental Health, The University of Western Australia, Australia; School of Psychiatry and Clinical Neurosciences, The University of Western Australia Graylands Hospital, Australia.
authors.forename: Flavie
authors.initials: F
authors.lastname: Waters
authors.affiliation: Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom; Department of Psychology, University of Roehampton, London, United Kingdom.
authors.forename: Paul
authors.initials: P
authors.lastname: Allen
authors.affiliation: University of Lille, CNRS UMR9193, SCA-Lab & CHU Lille, Fontan Hospital (CURE), Lille, France.
authors.forename: Renaud
authors.initials: R
authors.lastname: Jardri
authors.affiliation: Department of Neuroscience, The University of Sheffield, United Kingdom.
authors.forename: Peter W
authors.initials: PW
authors.lastname: Woodruff
authors.affiliation: University of Grenoble Alpes, Inserm, U1216, Grenoble Institute of Neuroscience, Grenoble, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: David
authors.affiliation: University Medical Center Hamburg-Eppendorf, Department of Psychiatry and Psychotherapy, Psychiatry Neuroimaging Branch, Hamburg, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Mulert
authors.affiliation: Department of Psychiatry, University of British Columbia, Vancouver, Canada; BC Mental Health and Addiction Research Institute, Vancouver, Canada.
authors.forename: Todd S
authors.initials: TS
authors.lastname: Woodward
authors.affiliation: Department of Neuroscience, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors.forename: André
authors.initials: A
authors.lastname: Aleman
mesh_terms: D001307:Auditory Perception / Q000502:physiology*; D006212:Hallucinations / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D007802:Language; D008568:Memory / Q000502:physiology*; D009415:Nerve Net / Q000473:pathology / Q000503:physiopathology*
keywords: Anatomical connectivity; Auditory processing; Auditory verbal hallucinations; DTI; EEG; Functional connectivity; Language; Memory; Psychosis; Schizophrenia; fMRI