Recent odor experience selectively modulates olfactory sensitivity across the glomerular output in the mouse
Narayan Subramanian1, Lee Min Leong1, Paria Salemi Mokri Boukani1,2
1Department of Biological Science, Florida State University, Tallahassee, FL, United States.
Chemical Senses
|January 9, 2025
Summary
Neural circuits in the mouse olfactory bulb adapt dynamically to odors. Recent odor experiences selectively shape neural responsiveness for over 30 seconds, aiding adaptation in complex scent environments.
Area of Science:
- Neuroscience
- Olfactory System Research
- Sensory Processing
Background:
- Understanding neural circuits for odorant recognition in complex environments is incomplete.
- Adaptation in neural circuits is crucial for adjusting to sensory input while retaining important associations.
Purpose of the Study:
- To investigate the time course and scope of adaptation in the mouse olfactory bulb.
- To determine if adaptation acts broadly or selectively across glomerular populations.
Main Methods:
- Utilized 2-photon Ca2+ imaging from mitral/tufted glomeruli in awake mice.
- Measured glomerular responses and population odor representations across imaging sessions.
- Analyzed odor-concentration pairings with varying interstimulus intervals.
Main Results:
- Individual glomerular responses and overall population odor representations remained stable across sessions.
- Odor-concentration pairings with >30s intervals induced concentration-dependent, heterogeneous adaptation.
- Adaptation was independent of respiration and unlikely to originate from olfactory receptor neurons.
Conclusions:
- The olfactory bulb output reliably transmits stable odor representations.
- Recent odor experiences can selectively modulate neural responsiveness for over 30 seconds.
- Non-uniform adaptation across glomeruli may facilitate dynamic adjustments in complex olfactory environments.
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