Attentional modulation of neuronal variability in circuit models of cortex
Abstract
The circuit mechanisms behind shared neural variability (noise correlation) and its dependence on neural state are poorly understood. Visual attention is well-suited to constrain cortical models of response variability because attention both increases firing rates and their stimulus sensitivity, as well as decreases noise correlations. We provide a novel analysis of population recordings in rhesus primate visual area V4 showing that a single biophysical mechanism may underlie these diverse neural correlates of attention. We explore model cortical networks where top-down mediated increases in excitability, distributed across excitatory and inhibitory targets, capture the key neuronal correlates of attention. Our models predict that top-down signals primarily affect inhibitory neurons, whereas excitatory neurons are more sensitive to stimulus specific bottom-up inputs. Accounting for trial variability in models of state dependent modulation of neuronal activity is a critical step in building a mechanistic theory of neuronal cognition.
Article and author information
Author details
Funding
Simons Collaboration on the Global Brain
- Marlene R Cohen
- Brent Doiron
National Institutes of Health (R01 EY022930)
- Marlene R Cohen
National Science Foundation (DMS-1313225)
- Tatjana Kanashiro
- Gabriel Koch Ocker
- Brent Doiron
National Science Foundation (DMS-1517082)
- Gabriel Koch Ocker
- Brent Doiron
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animal procedures were in accordance with the Institutional Animal Care and Use Committee of Harvard Medical School (Harvard IACUC protocol number: 04214).
Copyright
© 2017, Kanashiro 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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