Postural control systems in developmental perspective.

How can the adult postural organisation be elucidated using an ontogenetic approach, and what questions can be raised about ontogenesis starting from the organisation of adult posture? These questions will be addressed taking three aspects of postural organisation. The first is the internal representation of erect posture, including the role played by the various sensory inputs in this representation. The second aspect relates to the variables which are controlled during erect posture: is it the body orientation with respect to the vertical or the localisation of the centre of gravity with respect to the feet which is controlled? The third aspect concerns the coordination between posture, equilibrium and movement, focusing on the role played by an internal representation of the external world and its interactions with the body segments in organising the anticipatory postural adjustments. The central organisation of coordinated control will also be considered. Each of these aspects will be discussed in relation to ontogenetic considerations.