NEURAL INDICES OF PHONOLOGICAL DEFICITS IN POOR READERS

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It is a well established fact that poor readers do significantly worse than their normal reading peers on tasks of phonological awareness, auditory phoneme discrimination, lexical access and verbal short-term memory. There is a growing consensus that these difficulties might stem from a unitary deficit in speech perception that impacts on the acquisition, representation and processing of language. Despite these major advances in behavioral research, the neural correlates of the impaired reading process remain undetermined. The general objective of this study is to investigate the nature and origin of speech perception deficits in reading disability using both behavioral and neuro- physiological (scalp-recorded event-related potentials or metabolic imaging measures) methods. To this end, two groups (n=20 per group) of good and poor readers, 7-9 years of age, will be compared on their perception of a variety of speech and nonspeech stimuli presented auditorily and visually. More specifically, we propose to examine the effects of phonetic manipulations (like degree of phonetic similarity) and rate of presentation on identification, discrimination, lexical access and recall in the context of syllables, single words and words embedded in sentences. Neural activation patterns corresponding to behavioral differences will be delineated. In summary, the goal here is to optimize on the tremendous resources available by way of behavioral and neurophysiological testing facilities to trace this difference in reading ability between the two groups to specific structures and patterns of activation in the brains. This endeavour will allow for the learning of new investigative techniques, as well as, the expansion of one's clinical research skills areas of study to include other communication disorders.