Show simple item record

dc.contributor.authorHjelmervik, Helene
dc.contributor.authorCraven, Alexander R.
dc.contributor.authorSinkeviciute, Igne
dc.contributor.authorJohnsen, Erik
dc.contributor.authorKompus, Kristiina
dc.contributor.authorBless, Josef Johann
dc.contributor.authorKroken, Rune Andreas
dc.contributor.authorLøberg, Else-Marie
dc.contributor.authorErsland, Lars
dc.contributor.authorGruner, Eli Renate
dc.contributor.authorHugdahl, Kenneth
dc.date.accessioned2020-06-16T12:42:37Z
dc.date.available2020-06-16T12:42:37Z
dc.date.issued2019-10-18
dc.PublishedHjelmervik, Craig-Craven, Sinkeviciute, Johnsen, Kompus, Bless, Kroken, Løberg, Ersland, Gruner, Hugdahl. Intra-Regional Glu-GABA vs Inter-Regional Glu-Glu Imbalance: A 1H-MRS Study of the Neurochemistry of Auditory Verbal Hallucinations in Schizophrenia. Schizophrenia Bulletin. 2020:46(3):633–642.eng
dc.identifier.issn0586-7614
dc.identifier.issn1745-1701
dc.identifier.urihttps://hdl.handle.net/1956/22629
dc.description.abstractGlutamate (Glu), gamma amino-butyric acid (GABA), and excitatory/inhibitory (E/I) imbalance have inconsistently been implicated in the etiology of schizophrenia. Elevated Glu levels in language regions have been suggested to mediate auditory verbal hallucinations (AVH), the same regions previously associated with neuronal hyperactivity during AVHs. It is, however, not known whether alterations in Glu levels are accompanied by corresponding GABA alterations, nor is it known if Glu levels are affected in brain regions with known neuronal hypo-activity. Using magnetic resonance spectroscopy (MRS), we measured Glx (Glu+glutamine) and GABA+ levels in the anterior cingulate cortex (ACC), left and right superior temporal gyrus (STG), and left inferior frontal gyrus (IFG), in a sample of 77 schizophrenia patients and 77 healthy controls. Two MRS-protocols were used. Results showed a marginally significant positive correlation in the left STG between Glx and AVHs, whereas a significant negative correlation was found in the ACC. In addition, high-hallucinating patients as a group showed decreased ACC and increased left STG Glx levels compared to low-hallucinating patients, with the healthy controls in between the 2 hallucinating groups. No significant differences were found for GABA+ levels. It is discussed that reduced ACC Glx levels reflect an inability of AVH patients to cognitively inhibit their “voices” through neuronal hypo-activity, which in turn originates from increased left STG Glu levels and neuronal hyperactivity. A revised E/I-imbalance model is proposed where Glu-Glu imbalance between brain regions is emphasized rather than Glu-GABA imbalance within regions, for the understanding of the underlying neurochemistry of AVHs.en_US
dc.language.isoengeng
dc.publisherOxford University Presseng
dc.rightsAttribution Non-Commercial CC BY-NC 4.0eng
dc.rights.urihttp://creativecommons.org/licenses/by-nc/4.0/eng
dc.subjectMagnetic resonance imaging (MRI)eng
dc.subjectMR spectroscopy (MRS)eng
dc.subjectschizophrenia, hallucinationseng
dc.subjectauditory verbal hallucinationseng
dc.subjectglutamateeng
dc.subjectGABAeng
dc.subjectGlxeng
dc.subjectexcitatoryeng
dc.subjectinhibitory (E/I) imbalance modeleng
dc.titleIntra-Regional Glu-GABA vs Inter-Regional Glu-Glu Imbalance: A 1H-MRS Study of the Neurochemistry of Auditory Verbal Hallucinations in Schizophrenia.eng
dc.typePeer reviewed
dc.typeJournal article
dc.date.updated2020-02-13T09:47:48Z
dc.description.versionpublishedVersion
dc.rights.holderCopyright 2019 the authorseng
dc.identifier.doihttps://doi.org/10.1093/schbul/sbz099
dc.identifier.cristin1747715
dc.source.journalSchizophrenia Bulletin
dc.source.pagenumber633–642
dc.identifier.citationSchizophrenia Bulletin. 2020, 46 (3), 633–642.
dc.source.volume46
dc.source.issue3


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record

Attribution Non-Commercial CC BY-NC 4.0
Except where otherwise noted, this item's license is described as Attribution Non-Commercial CC BY-NC 4.0