There are a number of tests that sports doctors use to detect neurological damage in athletes. Think of roadside sobriety tests the police like to conduct on passing motorists. These tend to be subjective, requiring visual assessment of hand-eye coordination, balance, and gait.
Researchers at Harvard’s Wyss Institute and Beth Israel Deaconess Medical Center developed a simple app for a touchscreen tablet, called NeuroAssess, that can more systematically perform neuromotor assessment. A circle on the screen has a block sliding along its circumference and the user must use a stylus to follow along. The tablet records the path of the stylus and provides a score based on how far it deviated from the moving block. Here’s a Wyss Institute video talking about the app:
Study abstract in Journal of Gerontology: Series A: Biological Sciences and Medical Sciences: Use of a Tracing Task to Assess Visuomotor Performance: Effects of Age, Sex, and Handedness