title: Neural substrates of sublexical processing for spelling.
abstract: We used fMRI to examine the neural substrates of sublexical phoneme-grapheme conversion during spelling in a group of healthy young adults. Participants performed a writing-to-dictation task involving irregular words (e.g., choir), plausible nonwords (e.g., kroid), and a control task of drawing familiar geometric shapes (e.g., squares). Written production of both irregular words and nonwords engaged a left-hemisphere perisylvian network associated with reading/spelling and phonological processing skills. Effects of lexicality, manifested by increased activation during nonword relative to irregular word spelling, were noted in anterior perisylvian regions (posterior inferior frontal gyrus/operculum/precentral gyrus/insula), and in left ventral occipito-temporal cortex. In addition to enhanced neural responses within domain-specific components of the language network, the increased cognitive demands associated with spelling nonwords engaged domain-general frontoparietal cortical networks involved in selective attention and executive control. These results elucidate the neural substrates of sublexical processing during written language production and complement lesion-deficit correlation studies of phonological agraphia.
authors.affiliation: University of Arizona, United States. Electronic address: demarco@email.arizona.edu.
authors.forename: Andrew T
authors.initials: AT
authors.lastname: DeMarco
authors.affiliation: University of Arizona, United States; Department of Neurology, University of Arizona, United States.
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Wilson
authors.affiliation: University of Arizona, United States.
authors.forename: Kindle
authors.initials: K
authors.lastname: Rising
authors.affiliation: University of Arizona, United States; Department of Neurology, University of Arizona, United States; Southern Arizona VA Health Care System, Tucson, AZ, United States.
authors.forename: Steven Z
authors.initials: SZ
authors.lastname: Rapcsak
authors.affiliation: University of Arizona, United States; Department of Neurology, University of Arizona, United States.
authors.forename: Pélagie M
authors.initials: PM
authors.lastname: Beeson
mesh_terms: D000328:Adult; D000381:Agraphia / Q000503:physiopathology* / Q000523:psychology; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000502:physiology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007802:Language; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009778:Occipital Lobe / Q000502:physiology; D011932:Reading; D013702:Temporal Lobe / Q000502:physiology; D014956:Writing; D055815:Young Adult
keywords: Phonological agraphia; Phonological processing; Spelling; Sublexical processing; Writing; fMRI