Proprioceptive discharges from stretch‐receptors in the knee‐joint of the cat

The mechanoreceptors of the rabbit mandibular incisor

“…Sand (1937) found a depressant action of urethane on the spontaneous discharge of sense organs of the lateral line of fish. Boyd & Roberts (1953) found 'rapidly adapting' receptors scarce compared with 'slowly adapting' ones in the cat's knee-joint, the ratio being 1/17, in comparison with the 1/5 ratio found in the present study. They also found the spikes of their 'rapidly adapting' discharges to be about 24 times as large as those of the 'slowly adapting' type: a similar ratio has been here reported.…”

“…4 are also comparable. Boyd & Roberts (1953) have reported a similar frequency range for the slowly adapting receptors of the cat's knee-joint. In making comparison it must be remembered that the present measurements were made on receptors 30 C below rectal temperature, that rectal temperature was not rigidly fixed, and that it is possible that the use of an anaesthetic modified the responses, although no effects on discharge were noted when the concentration of circulating urethane was increased.…”

“…It is of great interest that Boyd (1954) has been able to identify the 'rapidly adapting' receptor of Boyd & Roberts as an elongated lamellated corpuscle and the 'slowly adapting' receptor as a spray (or Ruffini) ending, since Lewinsky & Stewart (1936) illustrate apparently similar endings found in preparations from the periodontal membranes of cat and rabbit. Directionality A relationship between the direction of a mechanical stimulus and the response of a stimulated sensory receptor has been observed in mechanoreceptors of the lateral line organ of fish (Sand, 1937), and of the teeth (Pfaffmann, 1939a), vibrissae (Fitzgerald, 1940), and knee-joint (Boyd & Roberts, 1953) of the cat. The incisor tooth of the rabbit has provided a suitable preparation for examining this relationship in some detail.…”

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).…”

Communications

“…1 have been described in the capsule of the knee joint and in the temporo-mandibular joint of the cat (Boyd, 1954;Skoglund, 1956;Freeman & Wyke, 1964;Greenfield & Wyke, 1964). The spray type of ending was shown previously to be slowly 31P PROCEEDINGS OF THE adapting (Boyd & Roberts, 1953;Skoglund, 1956) and was presumed to signal joint position in a steady state. The lamellated ending on the other hand was of rapidly adapting type, responding to pressure and movement.…”