Abstract: The invention relates, to the field of motion tracking and sensorimotor assessment and training, by providing a method, system and software for tracking of a target by moving the head and neck or other body part in two or three-dimensional space. In particular the invention teaches a method to create incremental difficult classes of unpredictable movement patterns according to specific criteria. The created movement patterns can be used to accurately grade the deficits of movement control and other sensorimotor deficits of the head/neck and consequently a treatment can be prescribed which starts at each patient's impairment level by using the same method. The invention provides also a reliable and valid method to detect fraudulent neck compensation claims from genuine deficits by said assessment of sensorimotor function.