We study the mechanisms by which complex sounds, such as speech, are processed by the auditory system. We hypothesize that the auditory system generates internal models of the sensory world, and uses these models to extract meaning from complex sensory stimuli. One potential neuronal substrate for this generative model is the massive system of descending projections from the auditory cortex to virtually every level of the subcortical auditory system. These projections are critical for shaping the response properties of neurons in the auditory periphery, but very little is known about their functional organization.
We employ electrophysiological, novel optical, optogenetic, computational and advanced anatomical approaches to study the projections from the auditory cortex to subcortical structures. One specific set of issues that we address concerns the role of different cortical subnetworks in complex sound processing. For example, neurons in both cortical layer 5 and cortical layer 6 project to subcortical structures, and the neurons in these layers have very different intrinsic, integrative and synaptic properties. Our work explores the different roles that these groups of neurons play in the processing of complex sound.
Clinical/Translational: Our laboratory also has an interest aging-related auditory network dysfunction, particularly as it relates to changes in network properties in the auditory thalamus and cortex and novel imaging methodologies.