How They Type: Eye and Finger Movement Strategies in Typing of Individuals with Cerebral Palsy

Typing is essential for communication, yet the input behavior of individuals with cerebral palsy (CP) remains underexplored. We investigated 31 CP typists and 31 non-disabled controls using keystroke logging, eye tracking, and motion capture. Our study found that CP typists were slower and less rhythmically stable, but by prioritizing accuracy, their overall keyboard efficiency was comparable to controls. They adopted compensatory visual strategies such as shorter and more frequent fixations, greater reliance on the keyboard, and more gaze shifts, and displayed diverse finger usage strategies from single-finger to multi-finger input. We found that using more fingers did not necessarily result in faster typing. Subtype analysis showed spastic CP typists followed a "slow but steady" rhythm with consistent inter-key intervals, whereas athetoid CP typists exhibited a "fast but unstable" rhythm with greater variability, highlighting distinct mechanisms of typing in CP and providing insights for personalized assistive technologies.