Canonical goal-selective representations are absent from prefrontal cortex in a spatial working memory task requiring behavioral flexibility
Abstract
The prefrontal cortex (PFC)'s functions are thought to include working memory, as its activity can reflect information that must be temporarily maintained to realize the current goal. We designed a flexible spatial working memory task that required rats to navigate—after distractions and a delay—to multiple possible goal locations from different starting points and via multiple routes. This made the current goal location the key variable to remember, instead of a particular direction or route to the goal. However, across a broad population of PFC neurons, we found no evidence of current-goal-specific memory in any previously reported form—i.e. differences in the rate, sequence, phase or covariance of firing. This suggests such patterns do not hold working memory in the PFC when information must be employed flexibly. Instead, the PFC grouped locations representing behaviorally equivalent task features together, consistent with a role in encoding long-term knowledge of task structure.
Data availability
The data that support the main findings of this study are available at https://github.com/LeeA-Lab/Boehm_Lee_MSMGMR
Article and author information
Author details
Funding
Howard Hughes Medical Institute
- Claudia Böhm
- Albert K Lee
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 procedures were conducted in accordance with the Janelia Research Campus Institutional Animal Care and Use Committee (permit number #17-158).
Copyright
© 2020, Böhm & Lee
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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