What determines whether a change in the external environment evokes a motor response?

We address this question in an experimentally advantageous preparation, the mollusc Aplysia. We study food-induced changes in biting that occur under some circumstances and not under others. We focus on forms of short term plasticity that are important in this context, and characterize them using electrophysiological, morphological, behavioral, and imaging techniques. Current projects focus on mechanisms that regulate spike propagation in sensory neurons and mechanisms that regulate the efficacy of synaptic transmission.