Somatosensory activity relevant for motor output. A summary of presentations and discussion

Several aspects of the function of receptors which contribute to somatic sensations are reviewed. First, there is evidence for a role of large-diameter cutaneous afferents in the reflex regulation of precision movements by the hand. Second, large-diameter muscle afferents from the intrinsic muscles of the hand, probably from primary muscle spindle afferents, can evoke specific sensations of finger movement. Third, the variable relationship between discharges in human C fibers from the hand and the specific sensation of pain is investigated. Activity in large-diameter cutaneous afferents can probably modify this sensation. Finally, the properties of small-diameter afferent fibers innervating joints are shown to be consistent with a role in the reflex regulation of joint integrity.