TY - JOUR T1 - Odor concentration change coding in the olfactory bulb JF - eneuro JO - eNeuro DO - 10.1523/ENEURO.0396-18.2019 SP - ENEURO.0396-18.2019 AU - Ana Parabucki AU - Alexander Bizer AU - Genela Morris AU - Antonio E. Munoz AU - Avinash D. S. Bala AU - Matthew Smear AU - Roman Shusterman Y1 - 2019/02/01 UR - http://www.eneuro.org/content/early/2019/02/01/ENEURO.0396-18.2019.abstract N2 - Dynamical changes in the environment strongly impact our perception. Likewise, sensory systems preferentially represent stimulus changes, enhancing temporal contrast. In olfaction, odor concentration changes across consecutive inhalations (ΔCt) can guide odor source localization, yet the neural representation of ΔCt has not been studied in vertebrates. We have found that, in the mouse olfactory bulb, a subset of mitral/tufted (M/T) cells represents ΔCt, enhancing the contrast between different concentrations. These concentration change responses are direction selective: they respond either to increments or decrements of concentration, reminiscent of ON and OFF selectivity in the retina. This contrast enhancement scales with the magnitude, but not the duration of the concentration step. Further, ΔCt can be read out from the total spike count per sniff, unlike odor identity and intensity, which are represented by fast temporal spike patterns. Our results demonstrate that a subset of M/T cells represents ΔCt, providing a signal that may instruct navigational decisions in downstream olfactory circuits.Significance As an animal tracks an odor plume, concentration changes over time. Here we show that olfactory bulb neurons explicitly represent concentration changes between consecutive inhalations. This response property enhances temporal contrast, as in other sensory systems. Fine temporal spike patterns do not improve concentration change decoding. These signals may guide olfactory navigation in the natural environment. ER -