Human proprioceptive sensation.
What was the 'muscular sense' to Sherrington was later the 'joint sense', when it became the conventional wisdom that muscles are 'insentient'. These terms betray a view, still common in the field, that the basis of kinaesthetic sensibility must be either joint receptors or muscle receptors, but not both. However, the demonstrations that established that muscle receptors do have a role in kinaesthesia were not demonstrations that joint receptors play no part. Indeed, there have been specific demonstrations of kinaesthetic roles for joint receptors. It is clear that both muscle and joint receptors can be involved in giving specific kinaesthetic sensations, and that there is probably considerable redundancy between them. Furthermore, some cutaneous receptors give signals that could be the basis of quite good kinaesthetic performance, although there is not yet strong evidence of their being used for this. Apart from specific kinaesthetic roles for each receptor class, there is evidence of mutual facilitation between the submodalities. Sometimes this facilitation appears to be of a non-specific kind as seen for example in the dependence of kinaesthesia in the fingers upon cutaneous inputs.
Ian McCloskey
D
D
Prince of Wales Medical Research Institute, Randwick, NSW, Australia.