The role of glutamate and GABA in cognitive dysfunction in schizophrenia and mood disorders - A systematic review of magnetic resonance spectroscopy studies.
Level 4 - case-series / case-control
Systematic review of primarily cross-sectional and case-control neuroimaging (MRS) studies
PubMed 32107102 · doi:10.1016/j.schres.2020.02.001
What was done
Authors conducted a systematic review searching PubMed through April 15, 2019, to evaluate magnetic resonance spectroscopy (MRS) studies examining associations between glutamatergic and GABAergic neurometabolites and cognitive function in schizophrenia spectrum disorders and mood disorders. A total of 37 studies met inclusion criteria.
What was found
Neurometabolic alterations in glutamatergic and GABAergic systems were relatively consistently identified across both schizophrenia and mood disorders. However, the abstract reports no pooled quantitative effect sizes or specific statistical metrics, concluding that a clear relationship between these neurotransmitter alterations and cognitive deficits could not be established due to extreme cross-study variance.
Why it matters
Understanding how neurochemical disruptions map to cognitive deficits is essential for developing targeted psychiatric therapies. This review indicates that existing literature remains too fragmented to confirm mechanistic links between neurometabolite levels and specific cognitive impairments.
Limits
The review was limited to PubMed and did not perform a quantitative meta-analysis. Included studies exhibited substantial heterogeneity in clinical illness stage, psychotropic medication exposure, MRS acquisition sequences, brain regions examined, and data post-processing protocols.
Cited by
- context Elevated brain glutamate is observed on brain imaging in epilepsy, bipolar disorder, and schizophrenia.