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DISCUSSION 



Lewis: Prof. Kallmann, how far do you think the senile and pre-senile 

 psychoses necessarily contain something that is identical with the process 

 of deterioration which occurs in normal ageing? These conditions, 

 although commonly associated with old age, can occur at much younger 

 ages, down to 27 or 28 in rare instances, and I would have thought it 

 possible that morbid processes which precede the appearance of the 

 disease may have been present for very many years in both; the senile 

 psychoses and the pre-senile psychoses seen in Alzheimer's and Pick's 

 disease may have no more essential connection with the process of 

 ageing than, say, Huntington's chorea has. 



Kallmann: Huntington's chorea has been compared with the pathology 

 observed in an early ageing process. I would not be able to offer an 

 expert opinion on that. However, whatever is found in Alzheimer's 

 disease (especially in Alzheimer's, not so much in Pick's disease) is so 

 similar to the signs of ordinary ageing processes after the age of 80, 

 especially when it comes to senile plaques and so on, that it would be 

 difficult to think in terms of two entirely different entities. In some 

 families with Alzheimer's disease, various members in successive 

 generations have been found to be able to reach a very old age (80, 90, 

 some have reached the age of 98), except for those who show the symp- 

 tomatology of Alzheimer's disease. The question is complicated by the 

 fact that some family members don't show Alzheimer's disease. At least 

 histopathologically their brains look like Pick's disease, so that it can 



