686 PROBLEMS IN REGARD TO LOCALIZATION OP 



Similarly, it is possible that Agraphia, accompanied 

 by ' word-blindness,' might result from a lesion of the 

 left Visual Word-centre, and that the site of such lesion 

 might be contiguous to the posterior extremity of the left 

 Sylvian Fissure. 



Aphemia (that is, mere loss of Speech) could not be 

 produced by a lesion of this region of the Brain, because 

 destruction of the Auditory Word-centre would destroy 

 the revival of words for spontaneous Writing, as well as 

 for Speech so that the double condition Aphasia (or 

 an approximate state in which ' imitative ' Writing only 

 is possible), would necessarily result, instead of the more 

 special Aphemic state. 



It is clear, also, that if important tracts of the Auditory 

 and Visual Word-Centres are in reality situated somewhere 

 about the end of the Sylvian Fissures, and if the Kin- 

 sesthetic Word-Centres, both for Speech and Writing, are 

 situated in or somewhere in the neighbourhood of the 

 third frontal convolutions, Aphasia might in addition 

 be caused by lesions cutting across the commissural 

 fibres in any part of their course between these pairs 

 of centres. 



Clearly, if stimuli caused by the mental revival of 

 words do not (a) issue from the Auditory and Visual 

 Word-Centres ; if they (b) are stopped on their way there- 

 from to the corresponding Kinsesthetic Word-Centres; or 

 (c) if they are stopped in or on the other side of these latter 

 Centres, that is on their way to the left Corpus Striatum, 

 the result would, in each case, be the production of Aphasia, 

 although the situations of the lesions in these cases would 

 be altogether different. In the first case, too. we should 

 have Aphasia with much mental impairment ; in the 

 second case we should have Aphasia with trifling mental 

 impairment; whilst in the third case we should have the 



