title: Mapping the reading circuitry for skilled deaf readers: an fMRI study of semantic and phonological processing.
abstract: We examined word-level reading circuits in skilled deaf readers whose primary language is American Sign Language, and hearing readers matched for reading ability (college level). During fMRI scanning, participants performed a semantic decision (concrete concept?), a phonological decision (two syllables?), and a false-font control task (string underlined?). The groups performed equally well on the semantic task, but hearing readers performed better on the phonological task. Semantic processing engaged similar left frontotemporal language circuits in deaf and hearing readers. However, phonological processing elicited increased neural activity in deaf, relative to hearing readers, in the left precentral gyrus, suggesting greater reliance on articulatory phonological codes, and in bilateral parietal cortex, suggesting increased phonological processing effort. Deaf readers also showed stronger anterior-posterior functional segregation between semantic and phonological processes in left inferior prefrontal cortex. Finally, weaker phonological decoding ability did not alter activation in the visual word form area for deaf readers.
authors.affiliation: Laboratory for Language and Cognitive Neuroscience, San Diego State University, 6495 Alvarado Road, Suite 200, San Diego, CA 92120, USA. kemmorey@mail.sdsu.edu
authors.forename: Karen
authors.initials: K
authors.lastname: Emmorey
authors.forename: Jill
authors.initials: J
authors.lastname: Weisberg
authors.forename: Stephen
authors.initials: S
authors.lastname: McCullough
authors.forename: Jennifer A F
authors.initials: JA
authors.lastname: Petrich
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D003638:Deafness; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D019986:Persons with Hearing Disabilities; D010700:Phonetics; D011932:Reading; D012660:Semantics
keywords: Deaf; Left inferior prefrontal cortex; Phonology; Semantics; Word reading; fMRI