DISEASES OF THE NERVOUS SYSTEM 



by the above-mentioned causes, according to Hurst, are neurasthenia, 

 soldier's heart, stupor and amnesia, psychasthenia, hysteria, 

 exaggerated defensive reflexes, hyperthyroidism, hyperadrenalism, 

 and shell shock. 



The pathology of some of these conditions has been carefully 

 investigated by Mott. Many persons suffering from shell shock 

 have been permitted to go on duty to the tropics, with often un- 

 pleasant mental results. These persons are especially liable to be 

 influenced by the sun's rays. 



ENDEMIC PARALYTIC VERTIGO. 



Synonyms. — Vertige Paralysante, Vertige Ptosique, Gerlier's 

 disease, Kubisagari, Tourniquet. 



DBflnition. — Endemic paralytic vertigo is characterized by eye 

 symptoms, such as ptosis, dimness of vision, and by paralysis of 

 the neck and extremities. 



History, — The disease was first described, in 1884, by GerHer in 

 Ferney, in Switzerland, in 1886, and by Miura, in 1894, in Japan. 



Climatology. — It is known in France, Switzerland, and Japan, 

 where it is found in the northern provinces and in the island of 

 Shikoku. It begins in spring, attains its greatest numbers in 

 summer, and ends in autumn. 



.^Etiology. — The aetiology is entirely unknown, and hence there 

 are many theories, which suggest alcohol, poisoned bread and 

 lentils, and latent malaria; but the one which is favoured by both 

 Gerlier and Miura is the association of the disease with stables. 

 Gerher says that in the valley of the Lake of Geneva it is not 

 unusual for people to sleep in the stables; and Miura says that in 

 the regions affected in Japan it is usual to have the house so arranged 

 that a part is used as a stable, while the remainder is occupied by 

 the family. 



Further, it is associated with warm weather. Miura gives as. 

 exciting causes bodily exertion while hungry or after a full meal,, 

 writing, reading, steady at tent ion to any thing, uniform movements,, 

 or mixing with crowds; while the attacks are diminished b}^ rest 

 and change. Couchoud and Shionoya found a Gram-negative 

 coccus in the cerebro-spinal fluid. This they grew artificially, and 

 stated that they reproduced the disease by injecting this into cats. 



Pathology. — This is quite unknown. 



Symptomatology. — An attack begins with a blurring of objects, 

 everything appearing as if in a fog, together with ptosis, and, less 

 frequently, a diplopia due to paralysis of the internal rectus, with 

 sometimes photophobia, disturbances of colour vision, and hyper- 

 semia of the optic disc. Then follow disturbances of speech and loss 

 of power in mastication, and, in bad cases, of deglutition. At the 

 same time paralysis of the muscles of the back of the neck, the 

 back, and the extremities are observed. The head falls forward, 

 and is only raised with difficulty; hei^ce the nanje of the di3eci.se, 



