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Updated: Jul 5, 2026
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Using Looming Visual Stimuli to Evaluate Mouse Vision
Published on: June 13, 2019
Multiple modes of network homeostasis in visual cortical layer 2/3
Arianna Maffei1, Gina G Turrigiano
1Department of Biology and Center for Behavioral Genomics, Brandeis University, Waltham, Massachusetts 02454, USA.
Summary
Visual deprivation during development triggers distinct homeostatic plasticity in the rat visual cortex. Different methods of sensory loss activate unique compensatory mechanisms within the cortical microcircuit.
Area of Science:
- Neuroscience
- Developmental Neuroscience
- Systems Neuroscience
Background:
- Sensory experience shapes cortical microcircuits via Hebbian and homeostatic plasticity.
- The precise mechanisms and interactions of these plasticities at specific synapse types remain unclear.
Purpose of the Study:
- Investigate how two visual deprivation methods affect layer 2/3 microcircuits in the rat visual cortex during the critical period.
- Determine the specific forms of homeostatic plasticity employed and their impact on neuronal activity and excitation/inhibition balance.
Main Methods:
- Utilized lid suture (LS) and intraocular tetrodotoxin (TTX) to induce visual deprivation in rats.
- Analyzed spontaneous neuronal firing and excitation/inhibition (E/I) balance in acute slices of layer 2/3 visual cortex.
Main Results:
- Both LS and TTX increased spontaneous firing in layer 2/3 pyramidal neurons.
- TTX elevated the E/I balance by increasing spontaneous activity.
- LS decreased the E/I balance by reducing excitatory transmission, with compensatory increases in intrinsic excitability.
Conclusions:
- Layer 2/3 microcircuits employ diverse homeostatic plasticity mechanisms to adapt to visual experience loss.
- Multiple, potentially redundant, homeostatic plasticity forms ensure robust network compensation against sensory perturbations.
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