Neural coding and perception of learned vocalizations

Project Summary Hearing and voice are the principal instruments of human communication. Early auditory experience of speech organizes perception around native language(s) sounds for life. This early specialization of auditory processing facilitates language development and predicts adult proficiency. While the acoustic features of speech sounds differ across languages, the temporal structure of speech is constrained and hierarchical in all languages. An important goal in the pursuit to understand how we acquire and use speech and what goes wrong when we can’t use speech is determining how auditory encoding on multiple time scales relates to vocal communication structure, vocal learning and perception. We propose to integrate manipulations in vocal learning with precise measures of cortical auditory encoding and perceptual skills to determine the encoding properties that promote flexible learning of syllable structure and constrain the temporal organization of syllables (syntax), in songbirds. The proposed experiments will identify neural mechanisms whereby vocal communication behavior is both learned and genetically-determined. The significance of the proposed research to the NIH mission is three-fold. First, this work will identify auditory encoding capacities that support vocal learning. Second, the work will test the limits of vocal learning to identify neural and perceptual mechanisms that impose structure on the acoustic features and temporal organization of vocal communication behavior. Third, our results will provide insights into how manipulations of experience and training can improve the prevention, diagnosis and treatment of speech deficits such as those observed in children with auditory spectrum disorders.