The long-term goal of this project is to examine neural plasticity and auditory-perceptual learning in school-aged children with auditory-based learning disabilities. It is estimated that 5-9 percent of school-aged children in the United States have some kind of diagnosed learning disorder, and that an additional 3-5 percent have a diagnosed attention deficit disorder. Furthermore, it is common for children to qualify for both diagnoses. Previous research has established that many of these children exhibit perceptual deficits in response to auditory stimuli, suggesting that an auditory-perceptual deficit may underlie their learning disabilities. A separate line of research has focused on developing effective computer-based procedures for training the perception of difficult foreign language contrasts by monolingual adults. This work has identified several general principles of perceptual learning that are critical for achieving enhanced sensitivity to perceptually difficult acoustic-phonetic contrasts, the most important of which is exposure to a range of stimulus variability in the training set. In view of the fact that second-language learners and children with auditory-based learning disabilities both display diminished sensitivity to certain speech sounds, successful training approaches for one population may hold great promise for the other. Accordingly, this study will draw on findings from these two lines of research in an attempt to develop laboratory-based training procedures for children with auditory-based learning disorders. An important aspect of the design of the proposed study is that the battery of tests used to assess performance before and after training incorporates a wide range of auditory-perceptual tasks, ranging from a non-speech auditory discrimination task using simple tones and noise to ore complex spoken word recognition tasks. Thus, data from the proposed study will provide important information regarding the relationships between performance on a variety of auditory and speech perception tasks within individual subjects, as well as providing the means for investigating the effects of various training paradigms on performance on a range of relevant tasks. Further, using well-established electrophtsiologic techniques, we will examine the neurophysiologic changes that underlie auditory-perceptual learning. In this manner, we hope to shed light of the underlying sensory-perceptual deficit, as well as make advances towards the development of training procedures of these children.
