Recruitment of inhibition and excitation across mouse visual cortex depends on the hierarchy of interconnecting areas
Abstract
Diverse features of sensory stimuli are selectively processed in distinct brain areas. The relative recruitment of inhibitory and excitatory neurons within an area controls the gain of neurons for appropriate stimulus coding. We examined how such a balance of inhibition and excitation is differentially recruited across multiple levels of a cortical hierarchy by mapping the locations and strengths of synaptic inputs to pyramidal and parvalbumin (PV)-expressing neurons in feedforward and feedback pathways interconnecting primary (V1) and two higher visual areas. While interareal excitation was stronger in PV than in pyramidal neurons in all layer 2/3 pathways, we observed a gradual scaling down of the inhibition/excitation ratio from the most feedforward to the most feedback pathway. Our results indicate that interareal gain control depends on the hierarchical position of the source and the target, the direction of information flow through the network, and the laminar location of target neurons.
Article and author information
Author details
Funding
National Eye Institute (R01 EY016184)
- Andreas Burkhalter
McDonnell Center for Systems Neuroscience
- Andreas Burkhalter
National Eye Institute (R01 EY022090)
- Andreas Burkhalter
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Sacha B Nelson, Brandeis University, United States
Ethics
Animal experimentation: All experimental procedures were approved by the Institutional Animal Care and Use Committee at Washington University (protocol numbers 20130104 and 20160093) and conformed to guidelines set by the National Institutes of Health.
Version history
- Received: July 5, 2016
- Accepted: September 22, 2016
- Accepted Manuscript published: September 26, 2016 (version 1)
- Version of Record published: October 21, 2016 (version 2)
Copyright
© 2016, D'Souza et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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