Date of Original Version
© 2012 Giridhar and Urban. This is an open-access article distributed under the terms of the Creative Commons Attribution Non Commercial License, which permits non-commercial use, distribution, and reproduction in other forums, provided the original authors and source are credited.
Abstract or Description
Inhibitory circuits are critical for shaping odor representations in the olfactory bulb. There, individual granule cells can respond to brief stimulation with extremely long (up to 1000 ms), input-specific latencies that are highly reliable. However, the mechanism and function of this long timescale activity remain unknown. We sought to elucidate the mechanism responsible for long-latency activity, and to understand the impact of widely distributed interneuron latencies on olfactory coding. We used a combination of electrophysiological, optical, and pharmacological techniques to show that long-latency inhibition is driven by late onset synaptic excitation to granule cells. This late excitation originates from tufted cells, which have intrinsic properties that favor longer latency spiking than mitral cells. Using computational modeling, we show that widely distributed interneuron latency increases the discriminability of similar stimuli. Thus, long-latency inhibition in the olfactory bulb requires a combination of circuit- and cellular-level mechanisms that function to improve stimulus representations.
This work is licensed under a Creative Commons Attribution-Noncommercial 3.0 License
Frontiers in Neural Circuits, 6, 40-40.