THE GENETIC ORIGIX OF DExMENTIA PRAECOX 



SiR FREDERICK MOl T, K. B. E., M.D., L.L.D., F.R.S. 



Director of the Pathological Laboratory of the London 



County Council Mental Hospitals. 



Consulting Physician Charing Cross Hospital. 



In attempting to establish in Dementia Praecox the presence of an 

 organic lesión capable of producing such a clinical entity, examination has 

 been made of the nervous system and of the reproductive organs, in this 

 disease. 



The Nervous system has been investigated in twelve cases, the results 

 of which have been published. There is as Nissl, Alzheimer, Duston, KHp- 

 pel, L'Hermitte and others have described, a very widespread morbid mor- 

 phological change affecting the nucleus and the cytoplasm of the neuro- 

 nes, most marked in the cortex. The nuclei are swollen and irregular, w hile 

 their nucleoli often show an eosinophile instead of a basophile staining 

 reaction. 



The cytoplasm shows absence or a marked deficiency of the basophil 

 substance forming Nissl's granules, a tendency of the cytoplasm to 

 an acidophile reaction, and an excess of lipoid granules. The dendritic 

 processes of the cells are often broken, and there is frequently an irregular 

 arrangement of the cells in Meynert's columns. Where the neuronic 

 changes occur, there is a local glia cell proliferation, the cells being grou- 

 ped round and often adherent to dengenerated neurones. 



The above degeneration does not as a rule lead to death of the cell; 

 consequently although unable to function or function normally owing to 

 synaptic dissociation, the axon projections are intact. Thercfore there 

 is little or no fibre degeneration or wasting; the brain in consequence 

 may appear normal to the naked eye. 



With regard to the lipoid granules, these are not found in the nerve 

 cells of healthy young adults. They occur in varying amounts in various 

 fatal diseases, and have some relation to the length of time elapsing 



