Physiology imaging and computation in the olfactory system.
Research in my laboratory focuses on the understanding of the physiological mechanisms underlying functional and computational properties brain neuronal networks. These mechanisms are elucidated by detailed studies of the physiological properties of the synapses, cells, and circuits involved in the performance of a given task. Research in the lab focuses on how phenomena such as dendritic integration and synaptic plasticity may allow small groups of neurons to perform complex functions. For these experiments we make use of the techniques of whole cell recording, including paired recordings of synaptically connected cells, and optical imaging to acquire data from both in vivo and in vitro preparations.
My current interests center on the circuitry of the olfactory bulb. The olfactory bulb and the individual glomerular units of which it is comprised provide an ideal system for studying how physiological processes such as dendritic integration and synaptic plasticity play a functional role in a brain network. Current projects focus on how signals arriving at different glomeruli are integrated by the dendrodendritic synaptic connections made between neurons in the bulb. My recent work has described the lateral spread of inhibition and excitation within the network of the mitral and tufted cells, which are the output neurons of the olfactory bulb. These results have provided insights on the physiological mechanisms underlying the competitive interactions between mitral cells and on how these mechanisms shape odor representations at the level of the olfactory bulb
Understanding such computational properties of brain networks often requires the simultaneous acquisition of data from several cells within a network and/or from multiple locations within a single cell. Thus, I also am interested in the application and development of physiological and optical techniques that facilitate this sort of parallel data acquisition in vitro and in vivo.
Ermentrout, G.B., Galán, R.F. and Urban, N.N. Reliability, synchrony and noise. Trends Neurosci. Aug;31(8):428-34, 2008. Epub Jul 5, 2008.
Arevian, A.C., Kapoor, V. and Urban, N.N. Dynamic Gating of Lateral inhibition in the Olfactory Bulb. Nature Neuroscience. January 2008| doi:10.1038/nn2030].
Bagley, J., LaRocca, G., Jimenez, D.A. and Urban, N.N. Adult neurogenesis and specific replacement of interneuron subtypes in the mouse main olfactory bulb. BMC Neuroscience, Nov 9:8(1):92, 2007.
Kapoor V. and Urban N.N. Glomerulus-specific, long latency activity in the olfactory bulb granule-cell network. J. Neuroscience, 26(45):11709-19, 2006.
Galán, R.F., Fourcaud-Trocme, N., Ermentrout, G.B. and Urban N.N. Correlation-induced synchronization of oscillations in olfactory bulb neurons. J. Neuroscience, 26(14):3646-55, 2006.