Distinct recruitment of dorsomedial and dorsolateral striatum erodes with extended training
Abstract
Hypotheses of striatal orchestration of behavior ascribe distinct functions to striatal subregions, with the dorsolateral striatum (DLS) especially implicated in habitual and skilled performance. Thus neural activity patterns recorded from the DLS, but not the dorsomedial striatum (DMS), should be correlated with habitual and automatized performance. Here, we recorded DMS and DLS neural activity in rats during training in a task promoting habitual lever pressing. Despite improving performance across sessions, clear changes in corresponding neural activity patterns were not evident in DMS or DLS during early training. Although DMS and DLS activity patterns were distinct during early training, their activity was similar following extended training. Finally, performance after extended training was not associated with DMS disengagement, as would be predicted from prior work. These results suggest that behavioral sequences may continue to engage both striatal regions long after initial acquisition, when skilled performance is consolidated.
Data availability
Behavioral and single unit recording data have been deposited on G-Node, as well as the Matlab codes used to analyze the data and generate the figures.
Article and author information
Author details
Funding
National Institute for Health Research (R01DA035943)
- Patricia H Janak
National Institute on Alcohol Abuse and Alcoholism (R01AA026306)
- Patricia H Janak
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 carried out in accordance with the recommendations of the Guide for the Care and Use of Laboratory Animals (National Research Council, 1996), and was approved by the institutional animal care and use committee of Johns Hopkins University (protocols #RA17A244).
Copyright
© 2019, Vandaele 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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