40 



HANDBOOK OF Pin'SrOLOGY 



NEUROPHYSIOLOGY I 



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Fio. 25. Charles Scott Sherrington, from the drawing by Reginald Eves (reproduced by permis- 

 sion from Selected Writings of Sir Charin Sherrington, edited by D. Denny Brown. New Vorii: Hoeber, 

 1940). Right: Sherrington's classic picture of the areas for the scratch reflex in the dog. (From 

 Sherrington, C. S. The Integrative Action of the Nervous System. Cambridge: Cambridge, 1947.) 



limb frequently evokes an exten.sor movement in the 

 contralateral homologous limb [the crossed-extensor 

 reflex (229)]; that this reflex can also be centrally 

 inhiljited; and that after prolonged inhibitory stimu- 

 lation there is, on withdrawal of the stimulus, an in- 

 crease of contraction ['reflex reljound' (230)]. These 

 are only a few of the reflex phenomena that received 

 elucidation through .Sherrington's work. 



Out of a vast numljcr of laboratory experiments 

 grew his unifying hypothesis of reflex excitation and 

 reflex inhibition, and hence of an interdependence of 

 reflex arcs resulting in an integrative action of the 

 nervous system. .Sherrington's clas.sic book bearing 

 this title was published (231) when he was Professor 

 of Physiology at Liverpool University and was based 

 on lectures he gave at Yale University. The concepts 

 of 'the final common path,' of 'synaptic connections,' 

 of 'central inhilaition,' of 'central excitation" and of 

 'reciprocal innervation' are incorporated in modern 

 ph\siology which recognizes its deln to Sherrington. 

 The nineteenth century which had opened with only 

 one method for tracing fiber tracts — that of dissecting 

 them out as Bichat had done — gave to physiologists 

 two great new tools, the histological method of 



2'50. Sherrington, C. S. Strychnine and reflex inhibition of 

 skeletal muscle. J. Physiol. 36: 185, 1907. 



231. Sherrington, C. S. The Integrative Action of the .\ervous 

 System. New York; Scribners, 1906; new edition. Cam- 

 bridge: Cambridge, 1947. 



Wallerian degeneration and the technique of electrical 

 recordings. In the hands of \'ictor Horsley and his 

 associates, Gotch, Beever, Schafer and others, electro- 

 physiology of spinal-cord systems made great advances 

 which can be followed in the series of papers pub- 

 lished in the Philiisoji/itcal Transactions between 

 1886 and 1 89 1. An overall view of what could be 

 achieved by this new method is given in the Croonian 

 Lecture of Gotch and Horsley in 1891 (232). 



Towards the end of the century these techniques 

 were being applied, not only by Horsley, but by many 

 of his contemporaries to the study of the physiology 

 of the brain. 



PHYSIOLOG^■ OF THE BR.MN : DEVELOPMENT OF 

 IDE.'SiS AND GROWTH OF EXPERIMENT 



At the mid-eighteenth century, scientists seeking 

 knowledge of the brain could look back on a history 

 of their field that revealed a gradual evolution of 

 anatomical knowledge about its structure but only 

 conjecture about its physiology. 



Among the early Greeks the teachings of Plato had 

 placed man's rational faculties where we would put 



232. Gotch, F. .\nd Victor Horsley. On the mam- 

 malian nervous system, its functions and their localization 

 determined by an electrical method. Phil. Trims. B 182 

 267, 1 89 1. 



