Repeatability of Eye-Hand Movement Onset Asynchrony Measurements and Cerebral Palsy: A Case Study

In this paper we investigate if a participant with cerebral palsy displays a deficit in movement planning for simple pointing and gesture actions that are required to interact with a touchscreen. We performed a repeated measures case study with one participant with CP, and one typically developed (TD) participant. Measurements of the relative timing of eye and hand movements were made to see how they vary when participants have the opportunity to preplan a movement (by knowing where a target will appear), and to see if they were repeatable. As expected, the typically developed participant changed their coordination patterns when they could preplan a movement. This did not occur for the participant with cerebral palsy and suggests he has a reduced ability to preplan movements, or at least a preference to avoid doing so. This implies gesture based interaction to imagined targets could be less accessible to people with cerebral palsy. Visual affordances may help overcome this potential barrier. The relative timing of movements varied from session to session for the participant with CP, but not the TD participant.