Phasic and tonic neuron ensemble codes for stimulus-environment conjunctions in the lateral entorhinal cortex
- University of Toronto, Canada
- University of Montana, United States
- University or Toronto, Canada
Abstract
The lateral entorhinal cortex (LEC) is thought to bind sensory events with the environment where they took place. To compare the relative influence of transient events and temporally stable environmental stimuli on the firing of LEC cells, we recorded neuron spiking patterns in the region during blocks of a trace eyeblink conditioning paradigm performed in two environments and with different conditioning stimuli. Firing rates of some neurons were phasically selective for conditioned stimuli in a way that depended on which room the rat was in; nearly all neurons were tonically selective for environments in a way that depended on which stimuli had been presented in those environments. As rats moved from one environment to another, tonic neuron ensemble activity exhibited prospective information about the conditioned stimulus associated with the environment. Thus, the LEC formed phasic and tonic codes for event-environment associations, thereby accurately differentiating multiple experiences with overlapping features.
Article and author information
Author details
Kaori Takehara-Nishiuchi
Funding
Natural Sciences and Engineering Research Council of Canada (RGPIN-2015-05458)
- Kaori Takehara-Nishiuchi
Canadian Institutes of Health Research (MOP-133693)
- Kaori Takehara-Nishiuchi
Canada Foundation for Innovation (25026)
- Kaori Takehara-Nishiuchi
Natural Sciences and Engineering Research Council of Canada (396157093)
- Maryna Pilkiw
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 surgical and experimental procedures were approved by the Animal Care and Use Committee at the University of Toronto (protocol number: 20011400).
Copyright
© 2017, Pilkiw 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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Phasic and tonic neuron ensemble codes for stimulus-environment conjunctions in the lateral entorhinal cortex
eLife 6:e28611.
https://doi.org/10.7554/eLife.28611
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