title: Action possibility judgments of people with varying motor abilities due to spinal cord injury.
abstract: Predictions about one's own action capabilities as well as the action capabilities of others are thought to be based on a simulation process involving linked perceptual and motor networks. Given the central role of motor experience in the formation of these networks, one's present motor capabilities are thought to be the basis of their perceptual judgments about actions. However, it remains unknown whether the ability to form these action possibility judgments is affected by performance related changes in the motor system. To determine if judgments of action capabilities are affected by long-term changes in one's own motor capabilities, participants with different degrees of upper-limb function due to their level (cervical vs. below cervical) of spinal cord injury (SCI) were tested on a perceptual-motor judgment task. Participants observed apparent motion videos of reciprocal aiming movements with varying levels of difficulty. For each movement, participants determined the shortest movement time (MT) at which they themselves and a young adult could perform the task while maintaining accuracy. Participants also performed the task. Analyses of MTs revealed that perceptual judgments for participant's own movement capabilities were consistent with their actual performance- people with cervical SCI had longer judged and actual MTs than people with below cervical SCI. However, there were no between-group differences in judged MTs for the young adult. Although it is unclear how the judgments were adjusted (altered simulation vs. threshold modification), the data reveal that people with different motor capabilities due to SCI are not completely biased by their present capabilities and can effectively adjust their judgments to estimate the actions of others.
authors.affiliation: Faculty of Kinesiology & Physical Education, University of Toronto, Toronto, Ontario, Canada; Centre for Motor Control, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Gerome A
authors.initials: GA
authors.lastname: Manson
authors.affiliation: Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, California, United States of America.
authors.forename: Dimitry G
authors.initials: DG
authors.lastname: Sayenko
authors.affiliation: Centre for Motor Control, University of Toronto, Toronto, Ontario, Canada; Toronto Rehabilitation Institute, University Health Network, Toronto, Ontario, Canada; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Kei
authors.initials: K
authors.lastname: Masani
authors.affiliation: Faculty of Kinesiology & Physical Education, University of Toronto, Toronto, Ontario, Canada; Centre for Motor Control, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Rachel
authors.initials: R
authors.lastname: Goodman
authors.affiliation: Faculty of Kinesiology & Physical Education, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Lokman
authors.initials: L
authors.lastname: Wong
authors.affiliation: Toronto Rehabilitation Institute, University Health Network, Toronto, Ontario, Canada; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Milos R
authors.initials: MR
authors.lastname: Popovic
authors.affiliation: Faculty of Kinesiology & Physical Education, University of Toronto, Toronto, Ontario, Canada; Centre for Motor Control, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Luc
authors.initials: L
authors.lastname: Tremblay
authors.affiliation: Faculty of Kinesiology & Physical Education, University of Toronto, Toronto, Ontario, Canada; Centre for Motor Control, University of Toronto, Toronto, Ontario, Canada; Toronto Rehabilitation Institute, University Health Network, Toronto, Ontario, Canada.
authors.forename: Timothy N
authors.initials: TN
authors.lastname: Welsh
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007600:Judgment; D008297:Male; D008875:Middle Aged; D009068:Movement; D013119:Spinal Cord Injuries / Q000503:physiopathology*; D013997:Time Factors; D055815:Young Adult