This is a chronic disorder attributed to cerebral arteriosclerosis. It may be impossible to differentiate it from senile dementia and pre-senile dementia, which may coexist with it. Careful consideration of the patient's age, history, and symptoms may help determine the predominant pathology. Commonly, the organic brain syndrome is the only mental disturbance present, but other reactions, such as depression or anxiety, may be superimposed. If not of psychotic proportion, the condition is classified under Non-psychotic OBS with circulatory disturbance.