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gations of Flechsig, who concludes that the entire Rolandic region is to be 

 regarded as sensor as well as motor in function, and names it the area of 

 body feelings, or the somesthetic area. 



The clinic and post-mortem evidence as to the extent of the area of tactile 

 sensibility and its coincidence with the motor area is somewhat contradictory, 

 and in some respects apparently in opposition to the view of Flechsig. Thus, 

 Dr. C. K. Mills, whose skill in interpreting the phenomena of disease is well 

 known, states in this connection in his work on nervous diseases that "innu- 

 merable cases have been reported of lesions of the motor cortex without the 

 slightest impairment of sensibility." In several cases of excision of the 

 human cortex in the Rolandic region by surgical operations careful studies of 

 the patients failed to show any impairment of sensation. Other competent 

 observers, however, have reported a number of cases in which anesthesia 

 more or less pronounced and persistent has accompanied lesions of the motor 

 area. The explanation of these contradictory observations is not apparent. 



The olfactory area has been assigned to the uncinate convolution, the 

 anterior part of the callosal convolution, and the posterior part of the base of 

 the frontal lobe. Lesions in this region are frequently accompanied by 

 subjective olfactory sensations. 



The gustatory area has been assigned to the collateral convolution. 



The auditory area has been assigned to the posterior portion of the super 

 temporal convolution and to the retro-insular convolutions, the island of 

 Reil. Unilateral destruction of this region is followed by only a partial 

 loss of hearing in the opposite ear (owing to the partial decussation of the 

 cochlear nerve), which, however, may be recovered from after a time, owing 

 probably to a compensatory activity of the insular convolutions. Bilateral 

 disease of this region is followed by complete deafness. Within this area 

 there is a smaller region, disease of which is accompanied by word-deafness 

 only, the patient being unable to distinguish the tone intervals between 

 words and syllables and therefore hearing only confused noises. Object- 

 hearing has also a separate area of representation. 



The visual area has been assigned to a triangular shaped area on the 

 mesial surface of the occipital lobe, which includes the gray matter above 

 and below the calcarine fissure (the cuneus and upper part of the lingual 

 lobe), and to the gray matter of the first occipital convolution on the lateral 

 aspect of the occipital lobe. Focal lesions of this area on one side are followed 

 by lateral homonymous hemianopsia, which, however, does not involve, as a 

 rule, the fovea or macula. It is, therefore, the area of homonymous half- 

 retinal representation. The location of the area for macular or central vision 

 is uncertain. Henschen locates it in the anterior part of the area near the 

 extremity of the calcarine fissure, and asserts that in each area both maculae 

 are represented. From experiments made on monkeys Schafer locates it in 

 the same region. Beyond the limits of this visual area and on the lateral 

 aspect of the parietal lobe there is a region (the supra-marginal convolution 

 and angular gyrus) in which impressions of words and letters seen have 

 their representation. Destruction of this area by diseases is followed by 

 word- and perhaps letter -blindness, the patient being unable to recognize 

 words and letters seen because of failure to revive the memory images of 

 words and letters. The areas for visual sensations and optic memory 



