Establishing how the response properties of neurons in visual cortex emerge from the synaptic interactions of distinct circuit elements remains one of the fundamental challenges for visual neuroscience and is central to understanding the neural basis of visual perception and disorders of visual function. The experiments in this proposal continue our analysis of the functional organization of circuits in layer 2/3 of visual cortex by employing state of the art techniques to determine how the well-developed network of horizontal connections within layer 2/3 interacts with feedforward inputs from cortical layer 4 to shape the visual response properties of layer 2/3 neurons.
The first aim employs in vivo 2-photon imaging of calcium signals in combination with retrograde labeling techniques to determine, with single cell resolution, the visual response properties of the neurons that contribute to the horizontal network in layer 2/3.
The second aim employs in vivo optogenetic control of the activity of layer 2/3 neurons to assess how modulating the activity of horizontal inputs impacts the visually driven responses of layer 2/3 neurons. In the final aim, optogenetic techniques will be combined with in vivo intracellular recordings to assess the synaptic interactions that account for the contribution of horizontal connections to the response properties of layer 2/3 neurons. Taken together, these experiments should provide a wealth of new insights into the functional organization of the neural circuits in visual cortex-information that is essential for understanding the neural basis of visual perception and provides the foundation for evaluating disruptions of normal cortical function that are common in neurological and neuropsychiatric disorders.

Public Health Relevance

The proposed experiments will provide new insight into the functional organization of cortical circuits that is critical for addressing numerous visual, neurological, and psychiatric disorders that are grounded in cortical circuit dysfunction.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY006821-27
Application #
8500281
Study Section
Central Visual Processing Study Section (CVP)
Program Officer
Steinmetz, Michael A
Project Start
1987-09-01
Project End
2014-06-30
Budget Start
2013-07-01
Budget End
2014-06-30
Support Year
27
Fiscal Year
2013
Total Cost
$433,200
Indirect Cost
$205,200
Name
Max Planck Florida Corporation
Department
Type
DUNS #
022946007
City
Jupiter
State
FL
Country
United States
Zip Code
33458
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