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

• Published in: PLoS biology Vol. 13; no. 12; p. e1002312
• Main Authors: Kim, Sungshin, Ogawa, Kenji, Lv, Jinchi, Schweighofer, Nicolas, Imamizu, Hiroshi
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 01.12.2015; Public Library of Science (PLoS)
• Subjects: Adaptation; Adaptation, Physiological; Adult; Behavior; Brain Mapping; Cerebellar Nuclei; Data analysis; Experiments; Female; Fourier transforms; Functional Laterality; Humans; Kinetics; Magnetic Resonance Imaging; Male; Medical imaging; Memory, Long-Term; Memory, Short-Term; Middle Aged; Models, Neurological; Multivariate Analysis; Neurons - metabolism; NMR; Nuclear magnetic resonance; Parietal Lobe - metabolism; Psychomotor Performance; Sensorimotor Cortex - metabolism; Studies; Tomography; Variance analysis; Young Adult
• ISSN: 1545-7885; 1544-9173; 1545-7885
• DOI: 10.1371/journal.pbio.1002312

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.