Examining contemporary motor control theories from the perspective of degrees of freedom
Occupational therapy aims to restore independent living skills and to improve social participation for clients; therefore, optimising motor ability can be a major goal during intervention in clinical practice. Choosing the adequate approach for each client is critical to achieve treatment goals. As frame of reference is based on contemporary theories related to human behaviours, it is crucial to synthesise current theories of motor control for clinical application. In this review, four motor control theories were examined by the Bernstein's classical question: redundant degrees of freedom. By addressing the central issue in motor control theories, the strengths and weaknesses for each theory were discussed in detail. Classical literatures were selected for each theory and related references were reviewed as evidence to support the potential biological plausibility. The research of motor control theories have been developed for over centuries, researchers still strive to discover how human beings execute movements. To date, motor control theories were mainly proposed by three disciplines: biology, psychology and engineering. Each discipline has unique perspective to develop solutions for understanding the processes behind the execution of movement. For occupational therapists in clinics, it is imperative to integrate current knowledge and motor control theories into practice and to explore new approaches to treat clients with motor disability.