Programming Time as a Function of Number of Movement Parts and Changes in Movement Direction

Abstract

The question of whether changes seen in simple reaction time (SRT) as a function of response complexity (i.e., number of movement parts) should be considered as differences in the time needed to centrally program a motor response was addressed. Using a large-scale tapping response, 14 subjects contacted from one to five targets positioned in a straight line, while a second group of 14 subjects executed 90 degrees changes in direction in striking the targets. Results revealed that mean SRT and mean premotor time increased linearly as the number of movement parts increased, regardless of whether changes in movement direction had to be programmed, with the greatest increase occurring between one-, and two-part responses. Increases in motor time were not sufficient to account for the sizeable SRT effect. These findings support the position of increased central programming time for more complex responses, and also help establish some of the boundaries of the complexity effect.

Sequential Pointing in Children and Adults

“…This effect is reminiscent of the increase in mean latency observed when adults produce increasingly long sequences of finger or arm movements (Canic & Franks, 1989;Fischman, 1984;Henry & Rogers, 1960), of utterances (Monsell & Sternberg, 1981), and of keystrokes (Sternberg, Knoll, Monsell, & Wright, 1983). In all cases, it has been suggested that increasing RTs reflect a latency component that is used for advance planning of the entire sequence: the more elements in the sequence, the longer the time to plan them all.…”

The effect of distance on reaction time in aiming movements

“…Christina 1992;Fischman 1984;Klapp & Erwin 1976;Rosenbaum & Patashnik 1980;Quinn et al 1980;Klapp 1996;Khan et al 2006).…”

“…The basic finding of longer RT with increased movement complexity has been replicated by a large number of authors (e.g. Christina 1992;Fischman 1984;Klapp & Erwin 1976;Rosenbaum & Patashnik 1980;Sidaway, Sekiya & Fairbrother 1995;Quinn et al 1980;Klapp 1996;Khan et al 2006) although there is some debate over the precise factors that define movement complexity. Sidaway, Sekiya & Fairbrother (1995) and Lajoie & Franks (1997) found that RT increased when the size of a second target decreased in a serial aiming response (where two targets are contacted in a fixed order).…”

Planning and Representing Intentional Action

“…Third, the time it takes to begin with an action often reflects the action's complexity [30,31,32] or the number of steps it consists of [33,34,35], as well as the number of action features that could not be planned in advance of the reaction stimulus [36,37,38,39]. Thus, the amount of planning required seems to determine when people can begin to carry out an action.…”