title: Learning of scaling factors and reference axes for reaching movements.
abstract: TO further understand visuomotor transformations in reaching, we compared adaptation to display rotation and altered gain in planar movements. Healthy subjects moved a cursor on a screen by moving an indicator on a horizontal digitizing tablet with their unseen hand. Adaptation to rotation was less complete and was accompanied by markedly increased directional variability. Adaptation training on a single target generalized broadly for gain change, but poorly for rotation. We propose that the difficulty in adapting to rotation arises from the substantial demands on short-term working memory imposed by the need to determine the new reference direction. Adaptation to gain change makes more modest demands on short-term memory to recalibrate the visuomotor scaling factor.
authors.affiliation: Department of Rehabilitation Medicine, Columbia University, College of Physicians and Surgeons, New York, NY 10032, USA.
authors.forename: Z M
authors.initials: ZM
authors.lastname: Pine
authors.forename: J W
authors.initials: JW
authors.lastname: Krakauer
authors.forename: J
authors.initials: J
authors.lastname: Gordon
authors.forename: C
authors.initials: C
authors.lastname: Ghez
mesh_terms: D000222:Adaptation, Physiological; D000328:Adult; D001132:Arm / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D011597:Psychomotor Performance / Q000502:physiology*; D012399:Rotation