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CEREBRAL LOCALIZATION. 



There was a plan on foot in 1883 to reunite 

 the five republics in one confederacy, to be 

 called the United States of Central America. 

 This scheme was started in Guatemala, which, 

 under President Don Rufino Barrios, has a 

 tendency to exercise a sort of hegemony over 

 the remaining states, and the idea proba- 

 bly originated in the mind of Gen. Barrios 

 himself, who has an ambition to be elected 

 President of the Union, should the project 

 meet with the assent of the people at large. 

 For the present the plan has failed, owing, as 

 was supposed, to the avowed or secret jealousy 

 and intrigues of Don M. A. Soto, ex- President 

 of Honduras, while he was the executive of 

 that republic. Don M. A. Soto, however, left 

 his country, and retired into voluntary exile in 

 the summer of 1883, residing in San Francisco, 

 California, where he published some letters 

 provoking replies from Gen. Barrios. Finally, 

 he resigned his office. The alleged main ob- 

 stacle to the projected union thus seems to 

 have disappeared. (See articles on the several 

 republics.) 



CEREBRAL LOCALIZATION. The whole tend- 

 ency of recent anatomical study has been to- 

 ward greater accuracy in minute details. Such 

 knowledge as was to be gained by the scalpel 

 and forceps in the way of dissection has long 

 since been acquired. The microscope still re- 

 mains, however, and much is to be learned of 

 the minute anatomy and functions of parts the 

 gross appearances and relations of which have 

 long been understood. 



The theory of * cerebral localization," briefly 

 stated, is this : The brain is not a homogene- 

 ous organ, but a mass composed of a certain 

 number of diverse organs, to each of which be- 

 long certain definite physiological properties 

 and functions. The object of recent study has 

 been to locate these different functions each in 

 its own portion of the nerve-substance of the 

 brain: In a crude way, the general fact of a cer- 

 tain amount of cerebral localization has long 

 been admitted. For example, the sense of sight 

 has been located in a certain portion of the 

 cerebrum, as has the sense of smell in another. 

 The gray matter of the cerebral hemispheres 

 was supposed to be especially associated with 

 mental power, and the amount of the former to 

 be an index of the amount of the latter. The 

 nerve-fibers of the medullary portion and the 

 large ganglia at the base of the brain were sup- 

 posed to be especially connected with the act of 

 locomotion. Further than this, paralysis limited 

 to the leghad been connected with disease of one 

 of the large ganglia (the corpus striatum) and 



the adjacent medullary fibers at the anterior 

 portion of the organ ; while paralysis limited 

 to the arm had been similarly associated with 

 disease of another ganglion (the optic thala- 

 mus), and the* surrounding medullary fibers at 

 the posterior part of the brain. It was known 

 that, when the arm and leg were both affected, 

 the disease would probably be found in the 

 base of the brain, rather anteriorly if the leg 

 were chiefly affected, and posteriorly if the 

 paralysis were greater in the arm. The re- 

 spective functions of the anterior and pos- 

 terior tracts of the spinal cord were also 

 known, and the cerebellum or smaller brain, 

 to which the posterior or sensory tracts of the 

 cord were traced, was held to be on this ac- 

 count the especial seat of sensation. In 1863 

 a still further advance was made in locating 

 the cerebral center of articulate speech. The 

 disease known as aphasia consists either in a 

 loss of the memory of words, so that the suf- 

 ferer is unable either to speak or write the 

 particular word he wishes to use, or else in 

 a loss of the power to articulate a particu- 

 lar word or words, though the sufferer re- 

 members them perfectly, and can write them 

 correctly. In either of these cases it is evi- 

 dent that the diseased point in the brain must 

 be either at the center controlling the muscles 

 of articulation, or in the center of articulate 

 speech itself. Careful examinations of the 

 brains of such patients resulted- in locating 

 the lesion at a certain point in the anterior or 

 middle portion of the frontal lobe of the left 

 side, known as the "island of Reil," and sup- 

 plied with blood by the left middle cerebral ar- 

 tery. It was at first supposed to follow neces- 

 sarily from these investigations that the func- 

 tion of speech was confined to the left side of 

 the brain ; that as speech is learned by use, in 

 most persons only one side of the brain had 

 been educated for that purpose; and that as a 

 person is right-handed as respects movements, 

 he is left-handed as respects the faculty of 

 speech. More thorough study has weakened 

 the supposed force of the first discoveries, and 

 although it still seems to be a fact that in most 

 cases the center of speech is in the left anterior 

 portion of the brain, there have been several 

 reported cases of aphasia in which the lesion 

 was plainly at the corresponding point on the 

 opposite side.* 



These and a few other similar conclusions 

 constituted about all that was definitely known 

 as to the functions of the different parts of the 

 brain till within the past few years. The field 

 of study has always been attractive, both for 



