ANALOGIES BETWEEN CENTRAL MOTOR PROGRAMS FOR SPEECH AND FOR LIMB MOVEMENTS

Publisher Summary This chapter discusses analogies between central programs for limb movements and for speech. The idea of Sternberg et al. that centrally programmed movement need not be independent of feedback has been supported by a number of observations concerning the effect of afferent inputs occurring during locomotion. One of the most striking examples of interaction between peripheral input and centrally programmed movement has been provided by the work of Forssberg, Grillner, and Rossignol in a study of responses to tactile stimuli applied to the hind limb at different phases of the step cycle in chronic spinal cats. It is known that such chronic spinal cats may exhibit locomotion in the absence of afferent input from the limbs. However, with afferent pathways intact, it was observed that when the limb was being flexed in the swing phase, a tactile stimulus applied to the dorsum of the foot enhanced flexion, leading the limb to be elevated so as to pass over the obstacle that delivered the tactile stimulus.