[Parkinson's disease and mental deterioration. Apropos of 30 cases].

The influence of Parkinson illness on intellectual faculties is appreciated in different ways. The existence of a real parkinson dementia is contested by some who see in the intellectual impoverishment of these patients a simple decline in efficiency. This is often partial and linked to neurological consequences which are not always taken into account by psychometric tests. 30 parkinson patients are beeing examined in this light. In spite of the small number, quite clear tendencies are apparent and which confirm the possible existence of these two types of phenomena, one beeing dementia and the other simply weakness without authentic senility. Risk factors are also isolated which emphasize age and accidents due to L-Dopa intolerance.