Dissociated sequential activity and stimulus encoding in the dorsomedial striatum during spatial working memory
Abstract
Several lines of evidence suggest that the striatum has an important role in spatial working memory. The neural dynamics in the striatum have been described in tasks with short delay periods (1-4s), but remain largely uncharacterized for tasks with longer delay periods. We collected and analyzed single unit recordings from the dorsomedial striatum of rats performing a spatial working memory task with delays up to 10s. We found that neurons were activated sequentially, with the sequences spanning the entire delay period. Surprisingly, this sequential activity was dissociated from stimulus encoding activity, which was present in the same neurons, but preferentially appeared towards the onset of the delay period. These observations contrast with descriptions of sequential dynamics during similar tasks in other brains areas, and clarify the contribution of the striatum in spatial working memory.
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Funding
NSF Office of the Director (GRFP)
- Hessameddin Akhlaghpour
NIH Office of the Director (5R01MH106689-02)
- Ilana Witten
McKnight Foundation
- Ilana Witten
Pew Charitable Trusts
- Ilana Witten
NIH Office of the Director (1 DP2 DA035149-01)
- Ilana Witten
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (1876-15) of Princeton University. All surgery was performed under anesthesia, and every effort was made to minimize suffering.
Copyright
© 2016, Akhlaghpour 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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