Information arrives in the glomerular layer of the AOB at synaptic pooling structures glomeruli (light blue circles) in which excitatory synapses between vomeronasal sensory neurons (VSNs) in the periphery and AOB mitral cells (red/pink) reside.
In the AOB, the arrangement of VSN-mitral synapses is different than seen in the main olfactory system. Each input glomerulus contains only synaptic terminals from VSNs expressing the same sensory vomeronasal receptor (VR). In the AOB, unlike the main olfactory bulb, multiple glomeruli are made per VSN type, and each mitral cell receives information from multiple glomeruli. Previous studies indicated that many mitral neurons combine sensory information from multiple types of inputs – meaning they are “synthesizing” a new smell by combining information from two separate channels into a single channel.
This unique property of the AOB remains largely unexplored. In the Meeks Lab, we are studying the specifics of information processing by mitral cells.
We are also interested in learning how modulatory signals from interneurons (darker blue neurons) may selectively enhance or inhibit certain olfactory cues. To do this, we are utilizing powerful ex vivo tools that allow us to study this circuit in great detail while we stimulate the periphery with natural and synthetic social odors.