Entrainment and maintenance of an internal metronome in supplementary motor area
- National Autonomous University of Mexico, Mexico
- Massachusetts Institute of Technology, United States
Abstract
To prepare timely motor actions we constantly predict future events. Regularly repeating events are often perceived as a rhythm to which we can readily synchronize our movements, just as in dancing to music. However, the neuronal mechanisms underlying the capacity to encode and maintain rhythms are not understood. We trained nonhuman primates to maintain the rhythm of a visual metronome of diverse tempos and recorded neural activity in the supplementary motor area (SMA). SMA exhibited rhythmic bursts of gamma band (30-40 Hz) reflecting an internal tempo that matched the extinguished visual metronome. Moreover, gamma amplitude increased throughout the trial, providing an estimate of total elapsed time. Notably, the timing of gamma bursts and firing rate modulations allowed predicting whether monkeys were ahead or behind the correct tempo. Our results indicate that SMA uses dynamic motor plans to encode a metronome for rhythms and a stopwatch for total elapsed time.
Data availability
MAT files with summary data for Figures 1-8, Figure 1-figure supplements 1&2, and Figure 7-figure supplement 1 have been provided. The full raw dataset is available on request to the corresponding author.
Article and author information
Author details
Victor de Lafuente
Funding
Consejo Nacional de Ciencia y Tecnología (Fronteras de la Ciencia 196)
- Hugo Merchant
Universidad Nacional Autónoma de México (PAPIIT IN207818)
- Victor de Lafuente
Consejo Nacional de Ciencia y Tecnología (Ciencia Básica 254313)
- Victor de Lafuente
Consejo Nacional de Ciencia y Tecnología (Ciencia Básica 236836)
- Hugo Merchant
Consejo Nacional de Ciencia y Tecnología (Fronteras de la Ciencia 245)
- Victor de Lafuente
Universidad Nacional Autónoma de México (PAPIIT IN202317)
- Hugo Merchant
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Experimental procedures were approved by the Ethics in Research Committee of the Institute of Neurobiology (protocol number 046) and were in agreement with the principles outlined in the Guide for Care and Use of Laboratory Animals (National Institutes of Health).
Copyright
© 2018, Cadena-Valencia 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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Entrainment and maintenance of an internal metronome in supplementary motor area
eLife 7:e38983.
https://doi.org/10.7554/eLife.38983
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