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TEXT-BOOK OF PHYSIOLOGY. 



definitely located. Ferrier assigned it to the hippocampal region. Schafer 

 and Horsely assigned it to the limbic lobe, and especially to that portion 

 known as the gyms fornicatus, or callosal gyms, as destruction of this convolu- 

 tion was followed by hemianesthesia of the opposite side of the body which was 

 more or less marked and persistent. These observers conclude that the limbic 

 lobe "is largely if not exclusively concerned in the appreciation of sensation, 

 painful and tactile." Other experimenters question this conclusion and 

 locate the area near to, if not within, the Rolandic area. The difference of 

 opinion regarding the location and probable limitation of the area of tactile 

 sensibility renders necessary additional and more conclusive experiments. 

 The olfactory and gustatory areas or areas of olfactory and gustatory 



FIG. 250. DIAGRAM OF THE MOTOR AND SENSOR AREAS ON THE LATERAL SURFACE OF THE 

 MONKEY BRAIN. (After Horsley and Schafer.} 



perception have been located in the uncinate gyrus or uncus and the adjacent 

 region, though their exact limits have not been determined by the experi- 

 ments thus far performed. 



The auditory area or area of auditory perception was located by Ferrier 

 in the upper two-thirds of the superior temporo-sphenoidal convolution. 

 Bilateral cauterization of this region gave rise to complete deafness, which 

 endured to the time of the animal's death, more than a year later. Unilateral 

 destruction of this region gave rise to deafness in the opposite ear only. The 

 results of experiments made subsequently by other observers would indi- 

 cate that the auditory area is somewhat more extended than that designated 

 by Ferrier, as apparently animals regained their hearing, to some extent 

 at least, after complete recovery from the operation. The limit or extent of 

 the area is, however, uncertain. 



The visual area or area of visual perception has been located in the occipital 

 lobe, though in this, as in the previous instances, its exact limits have not 

 been positively determined. Experimenters also are not in accord as to the 

 relative functions of its different parts. Ferrier located this area in the 

 occipital lobe and that adjacent portion of the parietal lobe on the outer 



