Submovement

A discrete component of a larger aimed movement, separated from other submovements by pauses or changes in velocity. According to the Optimized Submovement Model from motor performance theory, a rapid aimed movement such as moving a cursor to a target consists of an initial ballistic submovement followed by one or more corrective submovements that progressively reduce the remaining distance to the target. In able-bodied users, one or two submovements typically suffice, but motion-impaired users may require five or more submovements for the same task, including counterproductive submovements (moving away from the target) and overshoots (moving past the target). Analysing submovement structure reveals the specific mechanisms underlying pointing difficulties — such as pause frequency, speed-accuracy tradeoffs, and target slip-offs — providing a foundation for designing individually tailored cursor assistance.