EFFECTS ON THE BRAIN 1 89 



Vitamin Deficiencies. — Aside from rickets, which (as stated in Chapter V) 

 probably involves a vitamin factor in addition to the mineral deficiency, the 

 brain has been studied in beriberi (vitamin B deficiency) and scurvy (vitamin C 

 deficiency). Meyerstein ('22) made a few observations on the brain in young 

 white rats on diets deficient in vitamins A and B. Lopez-Lomba ('23) found 

 the brain unchanged in weight in pigeons on a vitamin-free diet. 



Beriberi. — The conspicuous neural symptoms in beriberi clearly indicate 

 lesions of the nervous system. These have been found chiefly in the spinal 

 cord and peripheral nervous system, but Rumpf and Luce ('00) cited observa- 

 tions by themselves and previous investigators indicating hyperemia and edema 

 of the brain, and occasionally slight hydrocephalus internus, in human beriberi. 

 In experimental beriberi of pigeons, chicks, cats, dogs and white mice, no definite 

 change was found in the nervous system. 



Walshe ('18, '20) has recently reviewed the literature and finds that "Since 

 the original investigations of Baelz, Scheube, Pekelharing and Winkler (1882- 

 1887) there has been a striking unanimity among pathologists that the nervous 

 lesion of beriberi is not specific for the disease, and is not to be distinguished from 

 that of a toxic polyneuritis." Walshe agrees with Eijkman that even though 

 beriberi be due to a vitamin deficiency ("Teilhungertheorie"), the ultimate 

 cause may yet prove to be a nervous poison produced by a disordered metabo- 

 lism arising from vitamin deprivation. 



McCarrison ('19, '19a, '21) believes that absence of the so-called "anti- 

 neuritic" factor, vitamin B, leads to functional and degenerative changes, not 

 only in the central nervous system, but also in every organ and tissue in the 

 body. In pigeons on a diet of autoclaved rice with butter and onions (deficient 

 in protein as well as in vitamin B), the brain shows an increase of 14 per cent in 

 weight, although this increase does not appear in polyneuritic pigeons on rice 

 diet alone. According to Findlay ('21) the brain in avian beriberi, though 

 nearly constant in weight (Table 13), shows a loss of Nissl granules and a 

 decrease in nucleic acid content, both of which are restored upon administration 

 of vitamin B. Hofmeister ('22) found in severe beriberi of rats marked lesions 

 with hemorrhages in the cerebellum and brain stem, which are proportional to 

 the nervous symptoms, and lead to degeneration of the brain cells. As no 

 evidence of a degeneration in the peripheral nerves was found, the condition in 

 rats is considered not a polyneuritis but rather a cerebral purpura similar to the 

 hemorrhagic encephalitis which occurs in chronic poisoning with alcohol, lead or 

 arsenical compounds. 



Scorbutus. — In scurvy, there are in general no specific changes in the nervous 

 system, aside from occasional hemorrhages, which Sato and Nambu found in the 

 brain once in 6 cases. There are no definite changes in the nerve cells or fibers, 

 according to the literature reviewed by Hess ('20). Bessesen ('23), however, 

 found an apparent average increase of 10-12 per cent in the weight of the 

 brain in scorbutic guinea pigs (Table 12). This is due to the fact that the loss 

 in brain weight is relatively less than the loss in body weight. 



Aqueous Inanition. — Schuchardt ('47) noted an apparent loss of 6 per cent 

 in the weight of the brain and cord in pigeons with loss of 44 per cent in body 



