Head-operated computer controls: effect of control method on performance for subjects with and without disability

Abstract

Head-operated computer controls provide an alternative means of computer access for people with physical disabilities. A person's ability to use such head controls may be reduced if he or she experiences neck movement limitations. Five experimental methods of compensating for neck movement limitations were evaluated in comparison to a standard head control interface. Twenty-two subjects without disabilities and three subjects with multiple sclerosis performed icon acquisition exercises using the standard interface and each of the five experimental compensation methods. Subjects without disabilities had less tendency to overshoot the target icons when using an interface with decreased sensitivity or one in which head movements controlled cursor velocity rather than cursor position (p<0.05). Subjects with multiple sclerosis tended to be more accurate when using an interface with increased sensitivity, and had less tendency to overshoot icons when using head movements to control cursor velocity rather than cursor position. Overall, subjects tended to demonstrate faster performance when using an interface with reduced sensitivity.