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The final part of the book addresses two issues: modeling of synergies and possible synergic organization of non-motor functions such as the language and the sensory function. Within the first issue, relations of synergies to the control theory is discussed with a brief overview of the central issues of the control theory such as open-loop and closed-loop control, and optimal control. Two models of synergies are described in more detail. One of them offers a neural network with back-coupling loops as the mechanism for multi-digit synergies. The other one suggests a scheme within which synergies emerge without any explicit feedback mechanisms. Further, the focus shifts to two aspects of synergies within the equilibrium-point hypothesis. One of them suggests that the principle of equilibrium-point control can by itself lead to synergies. The other deals with possible synergies in the hierarchy of control variables within the reference configuration hypothesis. The next two sections in this Part develop the notion of synergies for the sensory systems and for the production of human language. Multi-sensory interactions and synesthesia are described as possible reflections of sensory synergies. The book ends with an overview of its main points and a list of unsolved problems.

This chapter discusses studies focusing on children with hemiplegic cerebral palsy (CP) of any etiology. Topics covered include motor development after early focal lesions and the emergence of hemiparesis; the range of motor impairments; anatomical correlates of hemiparesis and motor reorganization; reorganization of the motor system; the range of sensory impairments; sensory-motor interaction; and organization and reorganization of the somatosensory system.

The presence of a fovea, a region with higher spatial resolution than the rest of the retina, coincides in vertebrate evolution with the emergence of several visual characteristics. Migration of the eyes from a lateral position to the front of the head produced significant overlap of the visual fields of the two eyes, allowing the emergence of binocular visual interactions. Sensory fusion and stereopsis allow a finely tuned perception of depth that emerges through the action of disparity detectors, cortical cells that compare the simultaneous inputs from the two eyes. The central topic of this chapter is an aspect of visual/motor development, specifically the development of binocular eye alignment in vergence (change in alignment of the visual axes of the two eyes to look at objects at different distances). Given the recognition of the importance of sensory–motor interactions during early development, it is perhaps surprising to find how little attention has been given to this factor in visual development.