EFFECTS ON THE BRAIN 187 



Frohner and Zwick C15) noted that the brain (like the body in general) 

 appears edematous in cattle on watery, low-protein diets. Koch and Voegtlin 

 ('16) found loss in the weight, and changes in chemical composition, of the body, 

 brain and spinal cord in monkeys and rats on diets of corn-oil cake, corn meal 

 and sweet potatoes, etc. (mixed deficiency). They conclude: "This is, we 

 believe, the first recorded instance in which such an atrophy of the central nerv- 

 ous system has been produced in animals by a change in diet." In monkeys and 

 pigs on these diets, Sundwall ('17) found a variable degree of meningeal conges- 

 tion, chromatolysis and other cell changes in the cortex, with occasional degen- 

 eration of fibers in the internal capsule. In albino rats stunted in growth by an 

 inadequate maize diet (mixed deficiency) after weaning, Holt ('17) noted a 

 slight increase in the brain weight. The relative weight of the olfactory bulbs 

 appears reduced (cf. opposite result by Stewart ('18a) on rats underfed from 

 birth), but the number of nerve cells therein is not affected. 



Pellagra. — The enormous literature on pellagra (assumed to be due primarily 

 to protein deficiency) contains many observations upon the associated changes 

 in the brain, which are of especial interest on account of the frequency with which 

 insanity follows pellagra. Only a few of the papers can be considered here, 

 however. For more complete review of the pathology of pellagra, with exten- 

 sive bibliographies, the works of Marie ('08, '10), Raubitschek ('15), Sundwall 

 ('17), and Harris ('19) may be consulted. 



The pioneer in this field wasLombroso ('69), who emphasized the importance 

 of the brain lesions in pellagra, including thickening and opacity of the meninges, 

 edema and softening of the cerebrum, atrophy of the cerebral cortex, abundant 

 corpora amylacea, and fatty and pigmentary changes in the cortical brain cells. 

 Fraenkel's ('69-'7o) extensive data were chiefly from Lombroso's clinic. Fraen- 

 kel in 113 autopsies found meningeal thickening in 33, purulent exudate in 4, 

 subarachnoid hemorrhages in 5, marked brain edema in 24, atrophy of cerebral 

 cortex in 11. The brain weight was variable; in 28 cases, 7 appeared increased 

 and 8 decreased. 



Tuczek ('93), however, in a careful study of 8 cases of pellagra, found nothing 

 abnormal in the cerebral cortex, cerebellum, pons and medulla, although the 

 nerve cells of the cranial nerve nuclei appear richly pigmented. Rossi ('98) noted 

 cytoplasmic vacuolation, pigmentation and disintegration of the Nissl bodies, 

 sometimes also nuclear displacement and degeneration, in the cerebral cortical 

 cells of pellagrins. These findings in the brain cells were confirmed and extended 

 by Babes and Sion ('00), and several other investigators cited by Harris ('19). 

 Parhon and Papinian ('05) and others demonstrated lesions in the neurofibrillae 

 of the pyramidal cells in the cerebral cortex, especially in the large Betz cells. 

 Marinesco ('09) found that the brain cells undergoing chromatolysis also show 

 pigmentary degeneration. The neuroglia proliferates. He found, as an excep- 

 tion, that the cells of Purkinje remain normal; but Harris ('10) noted marked 

 degenerative changes in the Purkinje cells in one case. Hamill ('12) observed 

 a variable chromatolysis in the large pyramidal cells of the cortex. 



The changes in the brains of insane pellagrins were thoroughly studied by 

 Kozowsky ('12), who found the meninges variably hyperemic and thickened. 



