Dataset Information

Neurochemical correlates of scene processing in the precuneus/posterior cingulate cortex: A multimodal fMRI and 1 H-MRS study.

ABSTRACT: Precuneus/posterior cingulate cortex (PCu/PCC) are key components of a midline network, activated during rest but also in tasks that involve construction of scene or situation models. Despite growing interest in PCu/PCC functional alterations in disease and disease risk, the underlying neurochemical modulators of PCu/PCC's task-evoked activity are largely unstudied. Here, a multimodal imaging approach was applied to investigate whether interindividual differences in PCu/PCC fMRI activity, elicited during perceptual discrimination of scene stimuli, were correlated with local brain metabolite levels, measured during resting-state 1 H-MRS. Forty healthy young adult participants completed an fMRI perceptual odd-one-out task for scenes, objects and faces. 1 H-MRS metabolites N-acetyl-aspartate (tNAA), glutamate (Glx) and ?-amino-butyric acid (GABA+) were quantified via PRESS and MEGA-PRESS scans in a PCu/PCC voxel and an occipital (OCC) control voxel. Whole brain fMRI revealed a cluster in right dorsal PCu/PCC that showed a greater BOLD response to scenes versus faces and objects. When extracted from an independently defined PCu/PCC region of interest, scene activity (vs. faces and objects and also vs. baseline) was positively correlated with PCu/PCC, but not OCC, tNAA. A voxel-wise regression analysis restricted to the PCu/PCC 1 H-MRS voxel area identified a significant PCu/PCC cluster, confirming the positive correlation between scene-related BOLD activity and PCu/PCC tNAA. There were no correlations between PCu/PCC activity and Glx or GABA+ levels. These results demonstrate, for the first time, that scene activity in PCu/PCC is linked to local tNAA levels, identifying a neurochemical influence on interindividual differences in the task-driven activity of a key brain hub.

SUBMITTER: Costigan AG

PROVIDER: S-EPMC6563468 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Publications

Neurochemical correlates of scene processing in the precuneus/posterior cingulate cortex: A multimodal fMRI and <sup>1</sup> H-MRS study.

Costigan Alison G AG Umla-Runge Katja K Evans C John CJ Hodgetts Carl J CJ Lawrence Andrew D AD Graham Kim S KS

Human brain mapping 20190313 10

Precuneus/posterior cingulate cortex (PCu/PCC) are key components of a midline network, activated during rest but also in tasks that involve construction of scene or situation models. Despite growing interest in PCu/PCC functional alterations in disease and disease risk, the underlying neurochemical modulators of PCu/PCC's task-evoked activity are largely unstudied. Here, a multimodal imaging approach was applied to investigate whether interindividual differences in PCu/PCC fMRI activity, elicit ...[more]

PMID: 30865358

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Dataset Information

Neurochemical correlates of scene processing in the precuneus/posterior cingulate cortex: A multimodal fMRI and 1 H-MRS study.

Publications

Neurochemical correlates of scene processing in the precuneus/posterior cingulate cortex: A multimodal fMRI and <sup>1</sup> H-MRS study.

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