Adaptive Motor Behaviour in Response to Perturbations of Balance

Abstract

Following a lesion to any part of the neuromusculoskeletal system, disabled individuals have to relearn how to perform everyday motor actions. Research into balance suggests that postural adjustments are an integral part of motor performance. In clinical practice, therefore, balance should be trained as part of tasks, such as reaching for an object or standing up. So that an individual does not find a task so difficult that only an approximation of it can be practised, modification of the action may be necessary to deter the practice of adaptive motor patterns. These patterns illustrate the ability of the lesioned system to put together an action out of what remains of neural and musculoskeletal sub-systems, and seem to be functionally preferred, in that the action is performed in the most advantageous manner given the effects of the lesion, the nature of musculoskeletal linkages and the environment in which the action is performed. This perspective of the need for rehabilitation to address 'emergent' motor behaviours is congruent with the dynamical systems viewpoint of contemporary action theorists. An understanding that motor behaviour is emergent enables the prediction of movement dysfunction and the organisation of intervention to ensure adaptive behaviour is not learned as a substitute for optimal performance.