Sensorimotor Basis of Speech Motor Learning and Retention

Project Summary / Abstract This project will test a new model of speech motor learning, whose central hypothesis is that learning and retention are associated with plasticity not only in motor areas of the brain but in auditory and somatosensory regions as well. The associated experiments are motivated by the results of our preliminary work and each tests the new model in different ways. In Aim 1 we test the causal involvement in the retention of new learning of each of the main players in the model. If plasticity in any of auditory, somatosensory or motor cortex is central to retention, then suppression of its activity following learning using cTBS, should lead to an impairment. Aim 2 examines the temporal order in which neuronal changes are observed during learning. If auditory or somatosensory plasticity play a determining role in speech motor learning, changes in these areas should be detectable early and should also predict subsequent learning. Aim 3 examines circuit-level contributions to speech learning and retention. If plasticity in sensory as well as motor areas underlies learning or retention, it should be possible to identify sensory as well as motor areas whose baseline functional connectivity patterns predict subsequent learning and whose connectivity patterns following learning predict subsequent retention. Our preliminary work on each of the three aims supports the idea that there is plasticity in each of the primary systems which participate in speech motor learning (auditory, somatosensory, motor).