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Observations on Cerebbal Localization. 



By James Rollin Slonaker. 



Ever since Hitzig 1 in 1870 sent a voltaic current through the brain of 

 a wounded soldier and noticed a certain movement of the eyes, numerous 

 investigators have been busy furthering our knowledge of cerebral locali- 

 zation. 



Fritsch and Hitzig followed this discovery with many experiments on 

 the cerebral hemispheres of the dog and noticed that stimulation of certain 

 areas produced definite muscular movements on the opposite side of the 

 body. 



These experiments started many other investigators, among whom 

 may be mentioned Ferrier, 2 Munk, 3 Horsley and Schafer, 4 Heidenhain," and 

 Beevor and Horsley. The results of these and many later investigations 

 have formed the basis of an exact cortical localization in the brain of man. 



Numerous surgical operations and pathological observations have added 

 to our fund of knowledge, so that now the cortical areas governing certain 

 movements in man are quite definitely known. However, each new case 

 will further prove and assist in making the localized areas in man rnore 

 definite. "With this in view I present the following data which I have 

 gathered from the subject : 



Mr. Ralph R. Laxton of Atlanta, Ga., met with an accident which 

 fractured the skull near the median line in the Rolandic region. A por- 

 tion of the bone was removed to relieve the pressure on the brain. As life 

 was despaired of no metal plate was introduced, but the scalp simply 

 closed over. The wound healed and the subject finally recovered. The 

 external condition of the wound after recovery is that there is a more or 

 less circular depression about one and a half inches across, due to the 



1 Hitzig, Reiehc-rt u. Du Bois-Reyroond's Archiv., 1870. 

 - Ferrier, The Functions of the Brain, London, 1886. 



3 Munk, Die Functionen der Grosshirnrinde, Berlin, 1877-1880. 



4 Horsley and Schafer, On the Functions of the Marginal Convolution, Pro- 

 ceedings of the Royal Society, Xo. 231, March, 1884. Horsley, British Medical 

 Journal, Vol. II, 1884. 



■'• Ileidenhain. Pfltiger's Archiv f. l'hysiologie, 1881. 



Beevor and Horsley, A Record of the Results Obtained by Electrical Excitation 

 of the so-called Motor Cortex and Internal Capsule in an Orang-Outang (Simia 

 satyrus), Phil. Trans. Royal Soc, Vol. 181, B, 1890. 



