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Published on: September 11, 2017
Role of cortical feedback in regulating inhibitory microcircuits
1Department of Neurosciences, Case Western Reserve University, Cleveland, Ohio 44106, USA. bens@case.edu
Annals of the New York Academy of Sciences
|August 19, 2009
Summary
Inhibitory circuits in the olfactory bulb, particularly involving mitral and granule cells, are crucial for processing sensory information. Feedback from the piriform cortex dynamically modulates these circuits, impacting neural signal processing.
Area of Science:
- Neuroscience
- Synaptic Plasticity
- Olfactory System
Background:
- The olfactory bulb features complex inhibitory local circuits.
- A common microcircuit involves reciprocal dendrodendritic synapses between mitral cells and GABAergic granule cells.
Purpose of the Study:
- To review recent findings on the function of inhibitory circuits in the olfactory bulb.
- To explore the role of feedback projections in modulating neural processing.
Main Methods:
- Review of recent scientific literature.
- Discussion of experimental findings using two-photon guided microstimulation.
Main Results:
- Granule cell GABA release may depend on coincident mitral cell and piriform cortex inputs.
- Proximal and distal excitatory synapses on granule cells show distinct short-term plasticity.
- Piriform cortex feedback facilitates granule cell activation and modulates mitral cell inhibition.
Conclusions:
- Synaptic plasticity in feedback pathways allows for dynamic modulation of neural information processing.
- Downstream areas can selectively activate inhibitory interneurons to control circuit function.
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