Grant: Operating Grant

Our studies will help clarify the role of the cerebral cortex in adaptive mechanisms associated with an altered oral environment and the learning of new motor skills, and thus provide new insights into better rehabilitative strategies to exploit these cortical mechanisms. The studies employ microstimulation and nerve cell recordings in the sensorimotor area of the cerebral cortex representing orofacial sensory and motor functions in animals. We have already documented several properties of this face sensorimotor cortex, and also shown the critical role played by this cortical region in the control of orofacial movements that is dependent on orofacial sensory inputs into the brain, thus providing a scientific underpinning why cortical damage (e.g. from a stroke) can severely impair orofacial sensory and motor functions. We have also revealed the neuroplasticity of the cortical region associated with the animal's learning of a new orofacial motor skill, suggesting this cortical region is also vital for motor learning, consistent with our analogous findings in humans. We have in addition documented in animals that cortical plasticity occurs also following nerve injury or acute pain in the tongue and following changes to the teeth (alterations to the dental occlusion, i.e. the 'bite' of the teeth; or tooth extraction). We now plan to test if neuroplasticity occurs in the sensorimotor cortex in other orofacial conditions, such as a chronic pain state, and determine the contribution of certain brainstem regions to this neuroplasticity. We will also test if changes occur in the properties of nerve cells of the sensorimotor cortex in these conditions, and also as the animal learns the new orofacial motor skill. Such studies are fundamental for understanding how humans learn and acquire a new skill and how they adapt or not to an altered oral environment, and for the development of improved clinical approaches aimed at restoring oral function.