title: Response preparation changes following practice of an asymmetrical bimanual movement.
abstract: The purpose of the current study was to examine the effects of practice on the advance preparation of an asymmetrical bimanual movement. Participants performed 170 trials of a discrete bimanual aiming movement where the right arm moved twice the amplitude of the left, in response to an auditory "go" signal. During three of the first and last ten trials, the "go" signal was replaced with a startle (124 dB) stimulus, which is thought to trigger a prepared movement. Startle and non-startle (control) trials from early and late practice were compared on various kinematic and EMG measures. Results indicated that it is possible to pre-program a bimanual asymmetrical movement, and that advance preparation of movement amplitude changes with practice. Evidence was also provided that the different amplitude movements were performed using similar EMG timing between limbs, while adjusting the relative ratio of EMG amplitude. Furthermore, learning of the task appeared to be related to the ability to prepare the correct asymmetrical EMG amplitudes rather than changing the timing of the EMG pattern.
authors.affiliation: School of Human Kinetics, War Memorial Gymnasium, University of British Columbia, 210-6081 University Boulevard, Vancouver, BC, Canada. dmaslovat@langara.bc.ca
authors.forename: Dana
authors.initials: D
authors.lastname: Maslovat
authors.forename: Anthony N
authors.initials: AN
authors.lastname: Carlsen
authors.forename: Ryu
authors.initials: R
authors.lastname: Ishimoto
authors.forename: Romeo
authors.initials: R
authors.lastname: Chua
authors.forename: Ian M
authors.initials: IM
authors.lastname: Franks
mesh_terms: D000328:Adult; D001132:Arm / Q000502:physiology; D001696:Biomechanical Phenomena; D003213:Conditioning, Psychological / Q000502:physiology*; D004576:Electromyography; D005260:Female; D006801:Humans; D008297:Male; D009048:Motor Skills / Q000502:physiology*; D009068:Movement / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology*; D013216:Reflex, Startle / Q000502:physiology