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Using Optical Coherence Tomography and Optokinetic Response As Structural and Functional Visual System Readouts in Mice and Rats
Published on: January 10, 2019
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DISRUPTION OF TRANSTHALAMIC CIRCUITRY FROM PRIMARY VISUAL CORTEX IMPAIRS VISUAL DISCRIMINATION IN MICE
C McKinnon1, C Mo2,3, S M Sherman2
1Committee on Computational Neuroscience, University of Chicago, Illinois, USA.
Biorxiv : the Preprint Server for Biology
|February 20, 2025
Summary
Layer 5 (L5) corticothalamic circuits are crucial for visual perception. Inhibiting these circuits in the primary visual cortex impaired visual discrimination performance in mice.
Area of Science:
- Neuroscience
- Visual System Research
- Cortical Circuitry
Background:
- Layer 5 (L5) of the cortex projects to higher-order thalamic nuclei, forming transthalamic circuits.
- These circuits run parallel to direct corticocortical connections, but their function in perception is unclear.
Purpose of the Study:
- To investigate the role of L5-initiated transthalamic circuits in visual perception and behavior.
- To determine the necessity of these circuits for visual discrimination tasks.
Main Methods:
- Targeted optogenetic inhibition of L5 corticothalamic inputs from primary visual cortex (V1) to the pulvinar in mice.
- Mice performed a visual discrimination task involving drifting gratings of different orientations.
Main Results:
- Suppression of V1 L5 transthalamic circuits significantly impaired visual discrimination performance.
- Behavioral deficits were retinotopically specific to the inhibited V1 region.
Conclusions:
- L5-initiated transthalamic circuits are essential for visual perception and decision-making.
- These findings underscore the importance of transthalamic pathways in hierarchical sensory processing.
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