A STUDY OF A PLAINS INDIAN BRAIN 



J. J. KEEGAX 



From the Anatomical Department, University of Nebraska. Omaha, Nebraska 



EIGHT FIGURES 



IXTRODUCTIOX 



The priniaiy object of this paper is to furnish an account of 

 the morphology of the cerebral hemispheres of a North American 

 Indian brain, thereby filUng a gap in the literature of racial 

 cerebral anatomy. Although a large amount of work has been 

 done upon the Indian tribes from an anthropological stand- 

 point, no description of an Indian brain has, to my knowledge, 

 ever been given. The study of cerebral morphologA- has not 

 yet furnished characters distinctive of race, but the studies of 

 I^lli()t Smith ('04), Duckworth ('07), and others have revived 

 ail iiitcn'st ill this work and advanced groally tli(> inteq^retation 

 of sulci and gyri. 



The secondaiy but more im])ortant aim of tliis study. fi-oiii 

 which the conclusions are largely tleduced, is the application of 

 the principles of fissure relation to cortical areas, both in the in- 

 terpretation of sulci and in the comparison of cortical areas and 

 sulci of the two hemispheres and of other cerebra. This is 

 especially \'aluable in this case on account of the completeness 

 of the history and the exceptional mental abilities evidenced. 



The study of cortical localization has been conducted by two 

 methods, cortical stinudation and histological differentiation. 

 The most important names connected with the former method 

 are those of Sherrington and Griinbaum ('01) in their experi- 

 mental work upon the ape brain, supplemented by a few similar 

 observations upon the human cortex and numerous clinical ob- 

 servations proved by operation or autopsy. This work neces- 

 sarily gave results in only a few regions of the cortex, mainly 



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