# Dynamics of spike timing in olfactory bulb coding and neuromodulation

> **NIH NIH F31** · CORNELL UNIVERSITY · 2020 · $45,520

## Abstract

Project Summary
 The firing of action potentials in the principal neurons (collectively, MTCs) of the olfactory bulb (OB) is
modulated by the intrinsic dynamics of OB circuitry. These dynamics, arising from an interplay between the
subthreshold dynamics of MTCs and the synaptic dynamics of the OB external plexiform layer, generate
coordinated local field potential oscillations at gamma frequencies (roughly 40-80 Hz in vivo; 20-55 Hz in
vitro) and phase-constrain the timing of MTC action potentials with respect to these oscillations. While
these dynamics are known to be important for olfactory performance, it remains unclear which aspects of
this dynamical regulation of spike timing are important for odor encoding and OB function. In part, this has
been due to the limited capacity to control the intensity and timecourse of odor delivery on fine spatial and
temporal scales, along with the limited capacity of electrical stimulation in slice explants to deliver stimuli
with odor-like spatiotemporal properties.
 This project proposes to deliver “odor-like” stimuli to OB slices using spatiotemporally patterned
optogenetic stimulation, and to record MTC ensemble responses (spikes and local field potentials) using a
120-channel planar microelectrode array. This strategy enables precise control of both the afferent stimulus
and the neuromodulatory state of the circuit. By varying the spatiotemporal properties of these afferent
stimuli in accordance with explicit models of “odor quality”, “concentration”, and “sniffing”, their effects on
the regulation of spike timing among coordinated ensembles of activated MTCs can be determined. This
system provides a remarkable opportunity to elucidate the underlying metrics and mechanisms of sensory
encoding in the olfactory system.
 The project PI is experienced in cellular and molecular neuroscience, but is new to systems
neuroscience, optogenetics, electrophysiology, and the analysis of neuronal ensemble activity. His PhD
research will incorporate each of these techniques, including the design and vetting of data analysis
workflows for these complex datasets. Cornell University and his research mentor are providing all
necessary research resources and opportunities for technical training and intellectual engagement.

## Key facts

- **NIH application ID:** 9995374
- **Project number:** 5F31DC017382-02
- **Recipient organization:** CORNELL UNIVERSITY
- **Principal Investigator:** Jesse Werth
- **Activity code:** F31 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $45,520
- **Award type:** 5
- **Project period:** 2019-08-16 → 2022-08-15

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9995374

## Citation

> US National Institutes of Health, RePORTER application 9995374, Dynamics of spike timing in olfactory bulb coding and neuromodulation (5F31DC017382-02). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/9995374. Licensed CC0.

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