Discussion 147 



Lewis: The trouble is that no one except Gellerstedt in Uppsala has 

 examined, as far as I know, a large series of the brains of normal old 

 people who did not show dementia. Oscar Vogt made a study of a small 

 series of brains of very intelligent old people who had died without de- 

 terioration ; but of any representative series systematically examined it 

 is only Gellerstedt's that is on record, so we are held up constantly by 

 the lack of a norm. 



Lorge: Frederic D. Zeman, who has studied a large number of brains, 

 tells me that there is no relation between brain pathology and a previous 

 behavioural pattern. I don't know anything about longevity, so the 

 question is "What are you correlating with what?" You may get 

 corresponding gross anatomical pictures and yet not know what the 

 previous behavioural history really was. 



Kallmann: Even if something is so gross and conspicuous as senile 

 plaques, we do not yet know what it means in histological and bio- 

 chemical terms. 



Lewis: We had a family where several members of a sibship — two 

 sisters and a brother — had died of a pre-senile dementia coming on at 

 the age of 43-45. There were seven other sibs, and two of these (still 

 under 50) were becoming forgetful and incompetent, and apathetic. We 

 were able to get biopsy specimens of the brains of these two and they 

 showed argyrophil plaques and other features found in Alzheimer's 

 disease. This was an instance where the brain changes, taken in con- 

 junction with the clinical findings, clinched the diagnosis during life. 



Nicolaysen : Have any studies been made of the oxygen consumption 

 of the brain under various circumstances, in view of the fact that under 

 ordinary conditions the brain is responsible for about 20 per cent of the 

 basal metabolism? 



Lewis: Yes, there are studies on that. 



Best: Are there studies on each particular disease? 



Olbrich: Yes, Scheinberg, Kety and Fazekas in America have done 

 estimations of the blood reaching the brain, the oxygen uptake and sugar 

 uptake; and they have shown quite clearly that in correlation to the 

 norm in these cases the blood supply to the brain is diminished per 100 g. 

 of brain tissue. They found also that the sugar uptake and the oxygen 

 uptake were diminished. 



Prof. Kallmann, plaques and fibrillary changes of the Alzheimer type 

 are found in people who have no senile dementia at all, and many 

 senile dementia brains show no plaques and no fibrillary changes of the 

 Alzheimer type, so I don't know whether we are justified in correlating 

 the two things. You see plaques and you see fibrillary changes ; and you 

 say that is the brain of a senile dementia ; you speak to the clinician or 

 to the man who has known the person and find that there were no symp- 

 toms of senile dementia. How can you correlate morbid anatomy changes 

 or histological findings to a mental state which does not correspond? 



Kallmann: We know that the ability of a person to withstand the 

 effect of cerebral damage varies, but the thought that something so 

 gross as senile plaques has no meaning in relation to brain function is 

 difficult to follow. 



