John Hughlings Jackson. 



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National Hospital for the Paralysed and Epileptic till 1906, when he 

 retired from the active staff as Consulting Physician. At the National 

 Hospital in particular, Jackson found a rich field for his neurological 

 studies, towards which he was largely directed by the personal influence of 

 Brown-Sequard. 



During his earlier years he spent much time in reporting for the medical 

 journals cases of interest in the various metropolitan hospitals, and made the 

 acquaintance of the members of the staff of most of these institutions. 



Throughout the whole of his career as Physician to the London and 

 National Hospitals Jackson was busy with his pen, and his contributions to 

 the medical journals, lectures, etc., had amounted in 1902 to over 200 (vide 

 Bibliography appended to Sir W. Broadbent's Hughlings Jackson Lecture, 

 ' Brain/ vol. 26, 1903, p. 356, et scq.). Though frequently urged by his 

 friends to publish in a collected form his numerous contributions to medical 

 science, scattered in various journals, and practically inaccessible to the 

 great majority of students, he always made some excuse, and would not 

 allow anyone to edit them in case of any inaccuracy or misrepresentation, of 

 which he had a horror. 



His voluminous writings embrace clinical observations, biological and 

 philosophical speculations. In the latter the influence of Herbert Spencer, 

 of whom he was an intimate friend and admirer, is largely seen. There is 

 much repetition and iteration of the dominant ideas which form the 

 groundwork of his teaching. 



His style is frequently obscure, owing to the numerous provisos and 

 qualifications which he constantly introduced to prevent his being mis- 

 understood. But a noteworthy feature in his writings is that he never 

 failed to indicate any facts which seemed to contradict his own theories or 

 explanations. 



One of his earliest services to clinical medicine, and clinical neurology 

 in particular, was his demonstration that optic neuritis in cerebral disease 

 may be consistent with the most perfect vision. He strongly urged the 

 routine use of the ophthalmoscope in medicine, pointing out its incalculable 

 importance in diagnosis. Indeed, this cannot be over-estimated, for without 

 the ophthalmoscope the neuro-pathologist would be deprived of his most 

 potent instrument of investigation. 



It is, however, with his studies of convulsions and his views on the 

 evolution and dissolution of the nervous system that his name is best 

 known and most firmly associated. 



When Jackson began his clinical work, the views of Flourens on the 

 unity and indivisibility of the cerebral hemispheres were prevalent in the 

 schools. About the time (1861) when Broca had established the probable 

 relationship between aphasia and lesion of the third frontal convolution of 

 the left hemisphere, Jackson had already observed the relatively frequent 

 association of loss of speech with right hemiplegia, and in 1864 he had 

 already seen seventy such cases. 



