title: Age of acquisition effects on the functional organization of language in the adult brain.
abstract: Using functional magnetic resonance imaging (fMRI), we neuroimaged deaf adults as they performed two linguistic tasks with sentences in American Sign Language, grammatical judgment and phonemic-hand judgment. Participants' age-onset of sign language acquisition ranged from birth to 14 years; length of sign language experience was substantial and did not vary in relation to age of acquisition. For both tasks, a more left lateralized pattern of activation was observed, with activity for grammatical judgment being more anterior than that observed for phonemic-hand judgment, which was more posterior by comparison. Age of acquisition was linearly and negatively related to activation levels in anterior language regions and positively related to activation levels in posterior visual regions for both tasks.
authors.affiliation: Department of Linguistics, University of California, San Diego, La Jolla, CA 92093-0108, USA. rmayberry@ucsd.edu
authors.forename: Rachel I
authors.initials: RI
authors.lastname: Mayberry
authors.forename: Jen-Kai
authors.initials: JK
authors.lastname: Chen
authors.forename: Pamela
authors.initials: P
authors.lastname: Witcher
authors.forename: Denise
authors.initials: D
authors.lastname: Klein
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D002648:Child; D002675:Child, Preschool; D003423:Critical Period, Psychological; D003638:Deafness / Q000503:physiopathology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007223:Infant; D007231:Infant, Newborn; D007802:Language; D008279:Magnetic Resonance Imaging; D008297:Male; D011578:Psycholinguistics; D011930:Reaction Time; D012813:Sign Language