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Abstract How is information distributed across large neuronal populations within a given brain area? Information may be distributed roughly evenly across neuronal populations, so that total information scales linearly with the number of recorded neurons. Alternatively, the neural code might be highly redundant, meaning that total information saturates. Here we investigate how sensory information about the direction of a moving visual stimulus is distributed across hundreds of simultaneously recorded neurons in mouse primary visual cortex. We show that information scales sublinearly due to correlated noise in these populations. We compartmentalized noise correlations into information-limiting and nonlimiting components, then extrapolate to predict how information grows with even larger neural populations. We predict that tens of thousands of neurons encode 95% of the information about visual stimulus direction, much less than the number of neurons in primary visual cortex. These findings suggest that the brain uses a widely distributed, but nonetheless redundant code that supports recovering most sensory information from smaller subpopulations.
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Activity of cat premotor cortex neurons during visually guided stepping
Visual control of steps is critical for daily living, however, how it is achieved is not well understood. Here, we analyzed how neurons in the premotor cortex respond to the demand for visual control of steps on a complex surface. We conclude that premotor cortex neurons participate in the cortical network supporting visual control of steps by modifying the phase, intensity, and salience of their firing activity.
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- Award ID(s):
- 1912557
- PAR ID:
- 10482024
- Publisher / Repository:
- American Physiological Society
- Date Published:
- Journal Name:
- Journal of Neurophysiology
- Volume:
- 130
- Issue:
- 4
- ISSN:
- 0022-3077
- Page Range / eLocation ID:
- 838 to 860
- Subject(s) / Keyword(s):
- accuracy locomotion PTN vision walking
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1152/jn.00114.2023
