title: Guiding movements with internal representations: a reach-and-grasp task.
abstract: We investigated participants' ability to use internal representations of the environment to guide prehensile movements, when visual feedback was not available. Reaching and grasping performed with concurrent visual feedback was compared to conditions in which participants actively formed spatial images and passively encoded images from visual presented information. Movement times, the proportion of time spent after peak velocity and peak apertures, were greater when concurrent visual feedback was unavailable. Movement times increased as a function of premovement occlusion length, with passively encoded images resulting in shorter movement durations than actively formed images. The findings indicated that participants adapted their movement trajectories to compensate for the degradation of stored spatial information, when concurrent visual feedback was not available.
authors.affiliation: School of Kinesiology, Simon Fraser University. alissa.fourkas@uniroma1.it
authors.forename: Alissa D
authors.initials: AD
authors.lastname: Fourkas
authors.forename: Ronald G
authors.initials: RG
authors.lastname: Marteniuk
authors.forename: Michael A
authors.initials: MA
authors.lastname: Khan
mesh_terms: D000293:Adolescent; D000328:Adult; D030141:Feedback, Psychological / Q000502:physiology; D006801:Humans; D008568:Memory / Q000502:physiology*; D009068:Movement / Q000502:physiology; D011597:Psychomotor Performance; D013037:Spatial Behavior / Q000502:physiology*; D013647:Task Performance and Analysis; D014796:Visual Perception / Q000502:physiology