Precisely-timed dopamine signals establish distinct kinematic representations of skilled movements
Abstract
Brain dopamine is critical for normal motor control, as evidenced by its importance in Parkinson Disease and related disorders. Current hypotheses are that dopamine influences motor control by 'invigorating' movements and regulating motor learning. Most evidence for these aspects of dopamine function comes from simple tasks (e.g., lever pressing). Therefore, the influence of dopamine on motor skills requiring multi-joint coordination is unknown. To determine the effects of precisely-timed dopamine manipulations on the performance of a complex, finely coordinated dexterous skill, we optogenetically stimulated or inhibited midbrain dopamine neurons as rats performed a skilled reaching task. We found that reach kinematics and coordination between gross and fine movements progressively changed with repeated manipulations. However, once established, rats transitioned abruptly between aberrant and baseline reach kinematics in a dopamine-dependent manner. These results suggest that precisely-timed dopamine signals have immediate and long-term influences on motor skill performance, distinct from simply 'invigorating' movement.
Data availability
Original video files and extracted deeplabcut coordinates in .csv format are available publicly on Figshare in the Collection "Bova_Leventhal_2020 Precisely-timed dopamine signals establish distinct kinematic representations of skilled movements"
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Author details
Funding
National Institute of Neurological Disorders and Stroke (K08-NS072183)
- Daniel K Leventhal
Nvidia (GPU grant)
- Daniel K Leventhal
University of Michigan
- Daniel K Leventhal
Brain Research Foundation (BRF Seed Grant)
- Daniel K Leventhal
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 an approved institutional animal care and use committee (IACUC) protocol (#8407) of the University of Michigan. All surgery was performed under isoflurane anesthesia, and every effort was made to minimize suffering.
Copyright
© 2020, Bova 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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