Florin Albeanu: Parallel processing pathways in mammalian olfaction

Cold Spring Harbor Laboratory, NY, USA

Areas at the sensory periphery send feedforward signals to the cortex and, in turn, receive massive top-down cortical feedback. To date, the function and degree of specificity of such feedback loops remain poorly understood. In the mammalian olfactory system, the olfactory bulb (OB) output neurons, the mitral and tufted cells (MCs and TCs) differ in their intrinsic properties, local connectivity, and projection targets. Two important cortical targets of OB outputs, the anterior olfactory nucleus (AON) and the piriform cortex (PC) receive feedforward input predominately from TCs and MCs respectively. In turn, both AON and PC send massive glutamatergic projections back to local inhibitory interneurons across all layers of the bulb. I will present recent work from the lab indicating that these different bulb output channels receive differential and specific feedback from the PC and AON, and form two parallel feedforward and feedback loops which serve different computations in representing odor identity and concentration.
An emerging view of brain function is that of a simulator that generates predictions of sensory inputs via internal models which map the consequences of motor actions onto sensory outcomes. In the second half of the talk, I will introduce a novel closed loop olfactory behavioral paradigm, where animals continuously refine their motor actions based on the current and desired sensory percepts, as a framework for studying the neuronal substrates of internal models in sensorimotor integration.

Organized by

Benjamin Judkewitz