Speech Motor Control

Abstract

The purpose of the voluntary act comes pretty close to what is called semantics in speech research. By practice, anticipative motor acts become automatic and, automatization of all complicated movements is tried as soon as possible. In the motor field, Evarts in particular, has studied voluntary acts in monkeys by making an instruction act automatically in response to a proprioceptive stimulus after having trained the animal with the aid of a standard rewarding technique. This has made the monkey, so to speak, see the point of the experiment in which he willingly participates. A good example from the linguistic camp is Lubker's anticipative coarticulation, learned and automatized early in the life of the child. A complex sentence is generated by successive applications of transformation rules. All complex movements follow an inner grammar, particularly striking in the postural co-adjustments. While afferent feedback from the skin, the muscles, and the ear certainly contribute their share to the readjustment, their aid can hardly be the whole explanation of the resourcefulness of the central planner.