title: Selective enhancement of functional connectivity in the left prefrontal cortex during sentence processing.
abstract: We present the results of correlation analyses for identifying temporally correlated activations between multiple regions of interest. We focused on functional connectivity for two regions in the prefrontal cortex: the left inferior frontal gyrus (L. F3t/F3O) and the left precentral sulcus (L. PrCS). Temporal correlations of functional magnetic resonance imaging signals were separately examined during a sentence comprehension task and a lexical decision task, thereby averaging data throughout all voxels within a region of interest used as a reference region. We found that the reciprocal connectivity between L. F3t/F3O and L. PrCS was significantly enhanced during sentence processing, but not during lexico-semantic processing, which was confirmed under both auditory and visual conditions. Furthermore, significantly correlated regions were mostly concentrated in the left prefrontal cortex during the sentence task. These results demonstrate that the functional connectivity within the left prefrontal cortex is selectively enhanced for processing sentences, which may subserve the use of syntactic information for integrating lexico-semantic information.
authors.affiliation: Department of Cognitive and Behavioral Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Tokyo, Japan.
authors.forename: Fumitaka
authors.initials: F
authors.lastname: Homae
authors.forename: Noriaki
authors.initials: N
authors.lastname: Yahata
authors.forename: Kuniyoshi L
authors.initials: KL
authors.lastname: Sakai
mesh_terms: D000328:Adult; D001931:Brain Mapping; D003627:Data Interpretation, Statistical; D003657:Decision Making / Q000502:physiology; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007802:Language; D008279:Magnetic Resonance Imaging; D008297:Male; D009415:Nerve Net / Q000502:physiology*; D017397:Prefrontal Cortex / Q000502:physiology*; D011932:Reading