title: Neural Substrates Related to Motor Memory with Multiple Timescales in Sensorimotor Adaptation.
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.
authors.affiliation: Neuroscience Graduate Program, University of Southern California, Los Angeles, California, United States of America.|Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America.
authors.forename: Sungshin
authors.initials: S
authors.lastname: Kim
authors.affiliation: Cognitive Mechanisms Laboratories, Advanced Telecommunications Research Institute International, Keihanna Science City, Kyoto, Japan.|Department of Psychology, Graduate School of Letters, Hokkaido University, Sapporo, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Ogawa
authors.affiliation: Data Sciences and Operations Department, Marshall School of Business, University of Southern California, Los Angeles, California, United States of America.
authors.forename: Jinchi
authors.initials: J
authors.lastname: Lv
authors.affiliation: Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, California, United States of America.|EuroMov, Movement to Health Laboratory (M2H), Université Montpellier-1, Montpellier, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Schweighofer
authors.affiliation: Cognitive Mechanisms Laboratories, Advanced Telecommunications Research Institute International, Keihanna Science City, Kyoto, Japan.|Center for Information and Neural Networks, National Institute of Information and Communications Technology and Osaka University, Suita, Osaka, Japan.|Department of Psychology, Graduate School of Humanities and Sociology, The University of Tokyo, Tokyo, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Imamizu
mesh_terms: D000222:Adaptation, Physiological; D000328:Adult; D001931:Brain Mapping; D002529:Cerebellar Nuclei; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007700:Kinetics; D008279:Magnetic Resonance Imaging; D008297:Male; D057567:Memory, Long-Term; D008570:Memory, Short-Term; D008875:Middle Aged; D008959:Models, Neurological; D015999:Multivariate Analysis; D009474:Neurons / Q000378:metabolism*; D010296:Parietal Lobe / Q000378:metabolism; D011597:Psychomotor Performance; D066191:Sensorimotor Cortex / Q000378:metabolism*; D055815:Young Adult