Objective: To compare the effects of dyad and individual training on the learning of bimanual cup-stacking in individuals with chronic stroke.
Material and Method: Twenty participants were divided into dyad and individual groups. The dyad group performed the task
in pairs alternating between performing and observing, while the individual group performed individually. On the first day (acquisition phase: AP), all participants performed 20 trials. On the following day (retention phase: RP), they performed 10
trials; each participant individually performed five trials without verbal feedback followed by five trials with verbal feedback. The dependent measures were movement time (MT), which was a measure of motor execution, and reaction time (RT), a measure of motor planning.
Results: During the initial trials, the dyad group performed the task with longer MT. By the end of the AP, their time was significantly shorter. At the RP, only the dyad group maintained the improved MT of cup stacking. Although the RT was not different between the two groups at the RP, only the RT of the dyad group reduced significantly at the RP compared with block 1 of the AP.
Conclusion: In individuals with chronic stroke, the dyad training protocol greatly enhanced the execution speed of the bimanual cup-stacking task when compared with the individual training protocol. Planning the task also improves dyad training.

Keywords: Bimanual task, Dexterity, Observational learning, Stroke