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bioRxiv · 10.1101/2024.03.26.586830

Robust encoding of sub-sniff temporal information in the mouse olfactory bulb

Warner, T. P. A.·Tootoonian, S.·Schaefer, A. T.
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Abstract

SummaryThe sensory world is highly dynamic, and the temporal structure of stimuli contains rich information about the environment. Odour plumes are shaped by complex airflow that imprint information about the nature and spatial organisation of the olfactory environment onto their temporal dynamics. Whilst insects and mammals alike can discern high-frequency information, how temporal properties of the olfactory environment are represented in the brain remains largely unknown. Here, we presented temporally rich and systematically varying odour stimuli whilst electrically recording from the output neurons of the mouse olfactory bulb, mitral and tufted cells (MTC). We found that temporal aspects of odour stimuli could readily be read out from MTC responses, with a temporal resolution of up to 20 ms. Remarkably, temporal representation was virtually identical across three different odours. To understand which temporal features are encoded, we developed a single-cell model accurately describing both single-cell and population responses. Temporal receptive fields of MTCs translated between different odours, indicating that MTC tuning to odour quality and dynamics are partially separable. Together, this suggests a stereotypical representation of odour dynamics across projection neurons and can serve as an entry point into dissecting mechanisms underlying how information about the environment is extracted from temporally fluctuating odour plumes.

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Warner, T. P. A., Tootoonian, S., Schaefer, A. T.. 2024-03-29. Robust encoding of sub-sniff temporal information in the mouse olfactory bulb. https://doi.org/10.1101/2024.03.26.586830

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