Neural and Behavioral Aspects of Early Language Development
Presenter: Helen J. Neville, Ph.D.
Effects of Experience on the Development of the Language Systems of the Brain
I will review ERP and fMRI results of visual and language processing in normal adults and in those who have had different sensory and/or language experience. Taken together these studies suggest that within vision, audition, and language, different neural systems display considerable variability in the degree to which they are modified by early experience. Within vision, early auditory deprivation has most marked effects on the organization of systems important in processing motion information. Within the visual and auditory systems, sensory deprivation has greater effects on the representation of the peripheral than of the central fields. In addition, different subsystems within language display varying degrees of modifiability by experience. The acquisition of lexical semantics appears relatively robust and invariant even in individuals with markedly different timing and modality of language input. By contrast, systems active during grammatical and phonological processing display marked effects of alterations in the timing and nature of early language input. These results converge with other lines of evidence that suggest it is important to distinguish these different aspects of language, and they raise hypotheses about the initial development of these different language systems.
Parallel studies of normal infants, children, and adults and studies of those with abnormal development provide further evidence for the roles of genetic factors and experience in human neurobehavioral development. The results of these several different types of experiments provide evidence that some systems within the human brain retain the ability to change, adapt, and learn throughout life, while other aspects of human neural and behavioral development display multiple, specific and different critical periods.
Helen J. Neville was awarded the B.A. degree from the University of British Columbia, an M.A. from Simon Fraser University, and a Ph.D. from Cornell University. Her postdoctoral training was at the University of California at San Diego in the Department of Neurosciences. Her major research interests are the biological constraints and the role of experience in neurosensory and neurocognitive development in humans. Methods include behavioral measures and event-related brain potentials (ERPs), and structural and functional magnetic resonance imaging (fMRI). Her work experience includes Director of the Laboratory for Neuropsychology at the Salk Institute and Professor, Department of Cognitive Science, UCSD.
Dr. Neville is currently Professor of Psychology and Neuroscience, Associate Director of the Institute of Neuroscience, Director of the Brain Development Lab, and Director of the Center for Cognitive Neuroscience at the University of Oregon in Eugene. She has published in many books and journals including Nature, Nature Neuroscience, Journal of Cognitive Neuroscience, Cerebral Cortex, and Brain Research. She has received many honors, is a member of the Board of Governors of the Cognitive Neuroscience Society, is a member of the Academic Panel of Birth to Three, and is active in many educational outreach programs.
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