Computer-aided measuring of motor functions using pursuit tracking

The necessity of evaluating motor functions objectively and quantitatively is discussed. Tracking tasks and their appropriateness in assessing motor performance is reviewed. Motor performance can be effectively assessed by means of tracking tasks. A simple tracking device is presented which allows the measurement of motor performance in different conditions. It is pointed out that computers are well suited for driving the stimulus in tracking tasks as well as recording the performance in experiments based on tracking tasks. Differences between open and closed loop conditions, compensatory tracking, pursuit tracking, preview tracking and cognitive tracking are discussed. A flexible computer-controlled device is presented with which diverse experiments based on tracking tasks can be performed and their results recorded. A complete description of the user-oriented, interactive programs with which the experiments can be controlled and the relevant performance data can be recorded is given. An example of their application on measuring the effects of levodopa therapy on the motor symptoms of Parkinson's disease is presented.