Characteristics of knee joint receptors in the cat

Abstract

SUMMARY1. The conduction velocities of 278 posterior articular nerve fibres studied in dorsal root filaments ranged from 10 to 110 m/sec. The conduction velocities were distributed similarly to posterior articular nerve fibre diameters determined histologically.2. Two hundred and nine fibres were slowly adapting. Of these, 140 responded only at both marked flexion and marked extension, forty-seven responded only during flexion and twelve only during extension. Four slowly adapting fibres were activated specifically at intermediate joint positions. Outward twist of the tibia (abducting the foot) enhanced the discharge of most slowly adapting joint fibres.3. Two rapidly adapting receptor types were noted. Pacinian corpusclelike receptors (fourteen fibres) responded transiently to joint movement in any direction regardless of initial position. Phasic joint receptors (thirty fibres) were rapidly adapting at most joint positions but could give a low rate sustained discharge when strongly stimulated.4. Six slowly adapting posterior articular nerve fibres responded to succinylcholine, suggesting that they originated from muscle spindles. Spindle-like receptors were usually tonically active at intermediate joint positions.5. Eleven slowly conducting myelinated fibres responded only to extreme joint movement, which was probably noxious.

Spatial orientation of a limb using egocentric reference points

“…A reduction in spatial errors at the more distant spatial targets might be viewed as an unusual finding, but this pattern has been repeatedly found in studies requiring movements in the same plane of the body as those reported here (Diewert, 1976;Larish, Stelmach, & McCracken, 1979). Moreover, this result is consistent with neurophysiological evidence demonstrating that, as the limb approaches the extreme ranges of flexion and extension, joint receptor (Burgess & Clark, 1969) and muscle spindle (Matthews, 1972) activity increases, thereby providing the basis for a more accurate assessment of movement reproduction than at intermediate ranges of movement.…”

Processing Afferent Proprioceptive Information at the Main Cuneate Nucleus of Anesthetized Cats

“…Varying the joint angle produced steady increases in spike frequency during the intermediate range of joint movement and often silenced firing at the largest physiological angle of motion (for example, see Fig. 8C2), indicating that these neurons were probably not affected by joint receptors, since these are activated at the end positions of joint movement (Burgess and Clark, 1969;Clark and Burgess, 1975;McCloskey, 1978). A similar behavior was found when steadily tapping, with a Von Frey electrical probe, the region over a presumed muscle spindle that was most responsive for the cell under study.…”

Outflow and inflow in movement duplication

“…There is considerable evidence that, following passive stretch of muscle, only the joint receptors can calibrate accurately changes in direction and extent of movement (Boyd & Roberts, 1953;Skoglund, 1956;Rose & Mountcastle, 1959;Burgess & Clark, 1969). Anesthetization of the joint capsule abolishes the perception of passive movement but leaves the ability to perceive and duplicate voluntary movement unimpaired (Browne, Lee, & Ring, 1954).…”