FMRI activation in the middle frontal gyrus as an indicator of hemispheric dominance for language in brain tumor patients: a comparison with Broca's area.
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ABSTRACT:
SUBMITTER: Dong JW
PROVIDER: S-EPMC4990063 | biostudies-literature | 2016 May
REPOSITORIES: biostudies-literature
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fMRI activation in the middle frontal gyrus as an indicator of hemispheric dominance for language in brain tumor patients: a comparison with Broca's area.
Dong Jian W JW Brennan Nicole M Petrovich NM Izzo Giana G Peck Kyung K KK Holodny Andrei I AI
Neuroradiology 20160205 5
<h4>Introduction</h4>Functional MRI (fMRI) can assess language lateralization in brain tumor patients; however, this can be limited if the primary language area-Broca's area (BA)-is affected by the tumor. We hypothesized that the middle frontal gyrus (MFG) can be used as a clinical indicator of hemispheric dominance for language during presurgical workup.<h4>Methods</h4>Fifty-two right-handed subjects with solitary left-hemispheric primary brain tumors were retrospectively studied. Subjects perf ...[more]
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Project description:Accounts of the role of Broca's area in sentence comprehension range from specific syntactic operations to domain-general processes. The present study was designed to tease apart these two general accounts by measuring the BOLD response to two syntactically distinct long-distance dependencies that invoke abstractly similar predictive processes: backward anaphora and filler-gap dependencies. Previous research has observed distance effects in Broca's area for filler-gap dependencies, but not canonical anaphora, which has been interpreted in support of a syntactic movement account. However, filler-gap dependencies engage predictive mechanisms, resulting in active search for the gap, while canonical anaphora do not. Backward anaphora correct for this asymmetry as they engage a predictive mechanism that parallels the active search in filler-gap dependencies. The results revealed a distance effect in the pars triangularis of Broca's area for the backward anaphora condition, supporting a prediction-based role for this region rather than one for a particular syntactic operation.
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