The effect of movement uncertainty on reaction and movement times of learning disabled and normal boys.

This study examined the effect of potential stimuli, as a source of movement uncertainty, on the reaction time (RT) and movement time (MT) of learning disabled (LD) children during a simple running task. The ability of LD children to attend to a process stimuli is known to be inferior. Such a notion is relevant to motor skill development as it imposes on the child's ability to develop from movement consistencies to movement constancies. When confronted with movement uncertainty, LD children showed significant increases in RT and MT over a 4.6 m. run. The performance of normal controls remained constant, thus emphasizing the simplicity of the task. The importance of skill consistency was highlighted, as was the consideration of inferior psychological processes of LD children while implementing movement activities.