Recent research has converged to suggest that a basic deficit characterizing children with developmental language and reading disorders may be difficulty with phonological awareness. Both behavioral and electrophysiological studies have demonstrated that the phonological disorders of children with language and/or reading disabilities are highly correlated with more basic, sublinguistic, perceptual/motor deficits in temporal analysis. Although more severe and persistent in the auditory modality, temporal processing in other sensory modalities (visual, tactual) is also affected. For example, results from visual perceptual studies have shown that language and reading impaired children have an abnormality affecting selective processing of fast, transient, low contrast information. Anatomical and single-cell electrophysiological studies with animals have demonstrated that there are two pathways and modes of visual analysis, designated magnocellular and parvocellular. The magnocellular pathway selectively processes rapid, low contrast visual information. Based on results from behavioral studies, it has been hypothesized that dyslexics may have a selective affliction of the magnocellular pathway. Recent neuropathohistological studies on the brains of dyslexics and matched controls have pointed to a selective difference in cell size and density in the magnocellular but not parvocellular level of the lateral geniculate nucleus in dyslexics. This provocative finding provides the first direct link between neuroanatomical, physiological and behavioral deficits in developmental communication disorders, and suggests that a fundamental deficit in temporal analysis may play a key role in these disabilities. The impetus for the proposed conference is to bring together neuroanatomists, neurophysiologists, behavioral neuroscientists and clinicians who may not previously have interacted, for the purpose of integrating research pertaining to the neural basis of temporal processing and its implications for dysphasia and dyslexia. There is a pressing need for more basic research in developmental language and reading disorders. The ultimate goals of this conference are to 1) stimulate basic research pertaining to developmental language and reading disorders and 2) to provide for more rapid dissemination of basic research to clinicians. The attainment of this goal should be greatly enhanced by this timely conference as well as through the publication of the proceedings of the meeting which will be published in the Annals of the New York Academy of Sciences.
