THE MUSCULAR SENSE. 

 By C. S. Sherrington. 



Contents. — Definition of " Muscular Sense," p. 1002 — Views regarding the nature 

 of Muscular Sense, p. 1002— Charles Bell's "Sixth Sense," p. 1006— ThePeri- 

 pheral Apparatus of the Muscular Sense ; Histological Data, p. 1006 — Nerves 

 of Muscles and Tendons, p. 1007 — End-Bulbs and Pacinian Corpuscles, p. 1007 

 — Hypotheses as to the Mode of Excitation of the Peripheral End-Organs of 

 the Muscular Sense, p. 1009— Muscle-Reflexes, p. 1011 — The Performances of 

 Muscular Sense, p. 1013 — Perception of Posture, p. 1013— Perception of Passive 

 Movement, p. 1014 — Perception of Active Movement, p. 1016 — Objective 

 Effects of Loss of Muscular Sense upon "Willed Movement," p. 1018 — 

 Subconscious Character of Reactions of Muscular Sense, p. 1019 — Probable 

 Importance of Tonus for Co-ordination, p. 1020 — Apsesthesia produces Ataxy 

 of " Willed Movement," p. 1020 — Senso-paralysis, p. 1021 — Perception of 

 Resistance, p. 1021 — The Liminal Stimulus, p. 1021 — The Liminal Difference, 

 p. 1022 — "Adaptation," p. 1024 — Interpretation of Results, p. 1024 — Fusion 

 of Muscular with other Sensations, p. 1024. 



It is somewhat difficult to present a concise definition of the term 

 " muscular sense." Authorities have not been perfectly concordant in 

 their use of the term. It may perhaps best be taken to include all 

 reactions on sense arising in motor organs and their accessories. 



Views regarding the nature of Muscular Sense. 



At the outset of any inquiry into muscular sense arises a question 

 omissible for other senses. In the very expression " a sense " physi- 

 ology elsewhere postulates existence of an organ or organs placed 

 peripherally, that is, outside the central nervous system, whence afferent 

 channels convey to intrinsic " centres " impulses which there initiate 

 the physiological and psychological reactions of the sense. In the case 

 of the muscular sense, the existence of peripheral sense organs has been 

 by many denied. 



The view which dispenses with peripheral organs and afferent nerves for 

 the muscular sense has had powerful adherents (Bain, Helmholtz, Lewes, 

 Mach). It supposes that during movement, e.g. a willed movement, the 

 outgoing current of impulses from brain to muscle is accompanied by a 

 " sensation of innervation." Where a movement is to be precise, we do 

 become, in fact, acutely aware immediately in advance of the amount and 

 direction it is to assume. The very discharge into the motor nerves seems 

 thus itself to possess a sensual quality. 



An objection to this hypothesis is that it sunders sharply the sensations of 

 passive from those of active movement, whereas there is strong ground for 

 believing the two intimately allied ; see below, p. 1016. 



