Cerebral Organization for Language in Deaf and Hearing Subjects: Biological Constraints and Effects of Experience

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 95; no. 3; pp. 922 - 929
• Main Authors: Neville, Helen J., Bavelier, Daphne, Corina, David, Rauschecker, Josef, Karni, Avi, Lalwani, Anil, Braun, Allen, Clark, Vince, Jezzard, Peter, Turner, Robert
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences of the United States of America 03.02.1998; National Acad Sciences; National Academy of Sciences; The National Academy of Sciences
• Series: Colloquium Paper
• Subjects: Adult; American sign language; Auditory perception; Brain; Brain - anatomy & histology; Brain - physiology; Brain Mapping; Cerebral hemispheres; Deafness; Dominance, Cerebral - physiology; Hemispheres; Humans; Language; Language acquisition; Magnetic Resonance Imaging; Native languages; Neurology; NMR; Nuclear magnetic resonance; Papers from a Colloquium; Pattern Recognition, Visual - physiology; Persons With Hearing Impairments; Prefrontal cortex; Psychology; Reading; Sign Language; Speech Perception - physiology
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.95.3.922

Cerebral organization during sentence processing in English and in American Sign Language (ASL) was characterized by employing functional magnetic resonance imaging (fMRI) at 4 T. Effects of deafness, age of language acquisition, and bilingualism were assessed by comparing results from (i) normally hearing, monolingual, native speakers of English, (ii) congenitally, genetically deaf, native signers of ASL who learned English late and through the visual modality, and (iii) normally hearing bilinguals who were native signers of ASL and speakers of English. All groups, hearing and deaf, processing their native language, English or ASL, displayed strong and repeated activation within classical language areas of the left hemisphere. Deaf subjects reading English did not display activation in these regions. These results suggest that the early acquisition of a natural language is important in the expression of the strong bias for these areas to mediate language, independently of the form of the language. In addition, native signers, hearing and deaf, displayed extensive activation of homologous areas within the right hemisphere, indicating that the specific processing requirements of the language also in part determine the organization of the language systems of the brain.