Neural Substrates Related to Motor Memory with Multiple Timescales in Sensorimotor Adaptation

PLoS Biol. 2015 Dec 8;13(12):e1002312. doi: 10.1371/journal.pbio.1002312. eCollection 2015 Dec.

Abstract

Recent computational and behavioral studies suggest that motor adaptation results from the update of multiple memories with different timescales. Here, we designed a model-based functional magnetic resonance imaging (fMRI) experiment in which subjects adapted to two opposing visuomotor rotations. A computational model of motor adaptation with multiple memories was fitted to the behavioral data to generate time-varying regressors of brain activity. We identified regional specificity to timescales: in particular, the activity in the inferior parietal region and in the anterior-medial cerebellum was associated with memories for intermediate and long timescales, respectively. A sparse singular value decomposition analysis of variability in specificities to timescales over the brain identified four components, two fast, one middle, and one slow, each associated with different brain networks. Finally, a multivariate decoding analysis showed that activity patterns in the anterior-medial cerebellum progressively represented the two rotations. Our results support the existence of brain regions associated with multiple timescales in adaptation and a role of the cerebellum in storing multiple internal models.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adaptation, Physiological*
  • Adult
  • Brain Mapping
  • Cerebellar Nuclei
  • Female
  • Functional Laterality
  • Humans
  • Kinetics
  • Magnetic Resonance Imaging
  • Male
  • Memory, Long-Term*
  • Memory, Short-Term*
  • Middle Aged
  • Models, Neurological*
  • Multivariate Analysis
  • Neurons / metabolism*
  • Parietal Lobe / metabolism
  • Psychomotor Performance*
  • Sensorimotor Cortex / metabolism*
  • Young Adult

Grants and funding

Grant NSF BCS 1031899 to NS supported the behavioral experiment, computational modeling, and model-based fMRI part of this study. http://www.nsf.gov/div/index.jsp?div=bcs. Grant NSF CAREER Award DMS-0955316 to JL supported the SVD analysis of brain data. http://www.nsf.gov/div/index.jsp?div=DMS. Grant JSPS KAKENHI Grant Number 26120002 to HI supported the fMRI experiment and parts of imaging data analysis. http://www.jsps.go.jp/english/index.html. "Development of BMI Technologies for Clinical Application" SRPBS AMED and ImPACT Cabinet Office of Japan to HI supported parts of imaging data analysis. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.