Table 1, gives a brief outline to distinguish between the two. Though later on, in any given group, the clinical features overlap and there may be features of both. This type of approach probably helps us in defining the clinical syndrome and is hence a clinical, not an anatomical concept 5 . A brief list of each type and subtype with classical clinical presentation of each dementia syndrome is given below. Idiopathic basal ganglia calcifications.
History given by patient itself and associated psychopathology is usually present.
Multiple sclerosis, HIV encephalopathy-progressive multifocal, adult onset leukodystrophy. Vitamin B12, Vit. B1, folate, niacin. The above classification is for practical purposes and bedside approach to a given patient with dementia 4 . Many other classifications exit 3,6,7 on more or less the same basis. Classification probably facilitates the identification of diseases and is useful to remember one, when approaching for a diagnosis.