Figures & data
FIGURE 1. The reductive perspective. The activity of picking up a cup using a prosthesis is considered to reduce to a set of body functions. For example, a collection of muscles, tendons, joints, and a certain EMG signal with properties such as speed (v), force, and direction. Learning to coordinate all these body functions is subsequently considered to be reducible to acquiring a control system that coordinates the body functions.
FIGURE 2. (a). From a reductive perspective, the improvement in motor learning is measured by gauging body functions. Thus, the assumption is that one measures at the level of the underlying structure. This is indicated by the thought bubble. However, an emergent view (b) does not idealize the activity by neglecting the specific environmental coordination, goals and constraints involved in testing. The test for body functions is therefore not positioned below the level of activity, but next to it at the same level. (see text for details).
