title: Coding odorant concentration through activation timing between the medial and lateral olfactory bulb.
abstract: In mammals, each olfactory bulb (OB) contains a pair of mirror-symmetric glomerular maps organized to reflect odorant receptor identity. The functional implication of maintaining these symmetric medial-lateral maps within each OB remains unclear. Here, using in vivo multielectrode recordings to simultaneously detect odorant-induced activity across the entire OB, we reveal a timing difference in the odorant-evoked onset latencies between the medial and lateral halves. Interestingly, the latencies in the medial and lateral OB decreased at different rates as odorant concentration increased, causing the timing difference between them to also diminish. As a result, output neurons in the medial and lateral OB fired with greater synchrony at higher odorant concentrations. Thus, we propose that temporal differences in activity between the medial and lateral OB can dynamically code odorant concentration, which is subsequently decoded in the olfactory cortex through the integration of synchronous action potentials.
authors.affiliation: Developmental Neural Plasticity Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 35 Convent Drive, Bethesda, MD 20892-3703, USA.
authors.forename: Zhishang
authors.initials: Z
authors.lastname: Zhou
authors.forename: Leonardo
authors.initials: L
authors.lastname: Belluscio
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001931:Brain Mapping; D004566:Electrodes; D051379:Mice; D009812:Odorants; D009830:Olfactory Bulb / Q000502:physiology*; D018035:Receptors, Odorant / Q000378:metabolism; D012903:Smell / Q000502:physiology; D014018:Tissue Distribution
chemical_list: D018035:Receptors, Odorant