Impact of Age on Computer Input Device Use: Psychophysical and Physiological Measures

This study examined the effects of aging on performance and preferences for two computer pointing devices (e.g. mouse and trackball). Participants made simple point-and-click and click-and-drag movements to targets of varying distance (96 and 192 mm) and widths (3, 6 and 12 mm). The results show that older adults (mean age=70) moved more slowly than younger adults (mean age=32), particularly for distant targets, yet their movements were less variable. No age differences were found in movement time or variable error between the two devices. EMG (RMS) recordings from the forearm flexor and extensor muscles showed no age related differences in between mouse and trackball. However, ratings of perceived exertion (RPE) indicated that older adults perceived greater levels of exertion than younger adults when using the mouse during click-and-drag tasks. Given the reduced grip and pinch force of older adults, manipulation of the mouse and trackball required a greater percentage of their maximum voluntary contraction (MVC) compared to younger adults. In addition, the mouse requires a larger range of motion than the trackball. These findings in conjunction with the RPE results imply that the trackball may confer greater benefit for the older computer user.