Motor Function Time

The time required to execute a physical action such as pressing or releasing a key, clicking a mouse button, or moving a pointing device. In the Model Human Processor, motor function time for able-bodied users averages approximately 70 milliseconds per action. For motor-impaired users, this time can be significantly longer — research has found it to be approximately 50% slower on average, with much greater variability between individuals and between different input devices. Motor function time is a critical parameter in accessible interface design, affecting decisions about timeout durations, double-click speeds, and key repeat rates.