Spike-timing-dependent ensemble encoding by non-classically responsive cortical neurons
Abstract
Neurons recorded in behaving animals often do not discernibly respond to sensory input and are not overtly task-modulated. These non-classically responsive neurons are difficult to interpret and are typically neglected from analysis, confounding attempts to connect neural activity to perception and behavior. Here we describe a trial-by-trial, spike-timing-based algorithm to reveal the coding capacities of these neurons in auditory and frontal cortex of behaving rats. Classically responsive and non-classically responsive cells contained significant information about sensory stimuli and behavioral decisions. Stimulus category was more accurately represented in frontal cortex than auditory cortex, via ensembles of non-classically responsive cells coordinating the behavioral meaning of spike timings on correct but not error trials. This unbiased approach allows the contribution of all recorded neurons – particularly those without obvious task-related, trial-averaged firing rate modulation – to be assessed for behavioral relevance on single trials.
Data availability
The code and data underlying our analyses are freely available online (https://github.com/badralbanna/Insanally2017)
Article and author information
Author details
Funding
National Institute on Deafness and Other Communication Disorders (DC015543)
- Michele N Insanally
Howard Hughes Medical Institute (Faculty Scholarship)
- Robert C Froemke
NARSAD
- Michele N Insanally
- Ioana Carcea
James McDonnell
- Kanaka Rajan
Sloan Research Fellowship
- Robert C Froemke
National Institute on Deafness and Other Communication Disorders (DC009635)
- Robert C Froemke
National Institute on Deafness and Other Communication Disorders (DC012557)
- Robert C Froemke
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 performed in accordance with National Institutes of Health standards and were conducted under a protocol (#160611-03) approved by the New York University School of Medicine Institutional Animal Care and Use Committee.
Copyright
© 2019, Insanally 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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