86 The Post-central Gyrus in Tabes Dorsalis [CHAP. 



motor area ; and, altogether, the guiding conditions which would enable an observer to light upon 

 the area exhibiting the more or less delicate reactive cortical alterations consequent upon a tabetic 

 degeneration have been so shadowy, that any undertaking in this direction has been shunned as 

 hopeless. However, having acquired more definite information concerning the functions and 

 histology of the cortex of the central convolutions, and especially having found not only that 

 the cortex of the postcentral gyrus is entirely different from that of the precentral, but that 

 it presents certain features which seem to be possessed by sensory realms in common, and 

 also having learned from piecing together the evidence supplied by studies in degeneration 

 and development, that the cortical segment of the sensory tracts probably aims for the post- 

 central gyrus, it seemed reasonable in searching over the cortex to pay special attention to the 

 condition of the postcentral gyrus, for here if anywhere changes would in all likelihood be 

 found. This I have done, and the data set forth in the following pages, to my mind, carry 

 great weight. 



Unfortunately the second and third cases of which I have to give an account are not 

 instances of Tabes in the pure form, but are complicated with General Paralysis of the Insane. 

 However, as a set-off to the disfiguring histological complications of the latter disease, I may 

 say that a prolonged experience of the histology of the general paralytic cortex, and the 

 possession of an abundance of sections of the central convolutions from non-tabetic cases of 

 that affection have been taken advantage of in making comparisons and eliminations, hence, 

 I hope it will be allowed that the value of my observations is increased. 



CASE No. 1. 



For the hemisphere forming the subject of the following remarks I am indebted to Doctor F. VV. Mott, 

 Pathologist to the .London County Asylums, and I consider that I have been exceedingly fortunate in obtaining 

 it, as the individual from whom it was taken provided an tincotumonly pure case of Tabes and at the same 

 time a severe one. True it is that he was an inmate of Coluey Hatch for many years and died therein ; 

 but against this it can be shown that the mental aberration from which he suffered was slight in character, 

 in fact, merely sufficient to justify his detention, and certainly not of a kind to occasion disturbances of 

 cell lamination, or other changes, which would impair the value of the brain as a means to the determination 

 of the alterations therein which I believe to stand in direct association with the spinal disease. And the 

 results of the histological examination to be presently described are quite in accord with this surmise. 



The clinical history of the case and the account of the examination of the spinal cord, etc. are reported 

 at length in the Archives of Neurology, Vol. n, page 123, case 28 ; it formed one of the series of cases 

 of which Doctor Mott made use in his study of "Tabes in Asylum and Hospital Practice," and the following 

 resume is copied from that work. 



" Case 28. Tabes of 16 years' duration, commencing with optic atrophy, followed soon after by mania 

 with delusions of persecution ; subsidence of acute mental symptoms and gradual development of spinal 

 symptoms, which after 10 years led to helpless ataxy; mental enfeeblement, but no progressive dementia. 

 Death from acute dysentery. Tabic lesion of spinal cord and roots, in cervical and lumbo-sacral region, 

 especially ; affection of both exogenous and endogenous posterior spinal systems ; marked patchy thickening 

 over prefrontal, frontal and central convolutions ; chronic atrophy of superficial layers of fibres and cells of 

 cortex in these regions, without vascular changes. Was this a case of mania and tabes, or tabetic general 

 paralysis with arrest of mental symptoms ? " 



AVhen the specimen, a left cerebral hemisphere, reached me, it had already been fixed by immersion first 

 in Formalin and then in Muller's fluid. It was in excellent condition for section and on superficial naked 

 eye inspection exhibited no localised atrophy in the Rolandic region, and only a moderate degree of general 

 wasting. 



