Abstract
Dementias are classified as 1) vascular dementia, 2) Alzheimer's disease and senile dementia of Alzheimer type (SDAT), 3) dementias due to various neurodegenerative diseases and physical diseases like endocrine abnormalities, 4) pseudodementia.
In this article, clinicopathological features of Alzheimer's disease and SDAT are described in detail. Alzheimer's disease is characterized by memory disturbance (especially loss of recent memory), desorientation, especially of spatial one, various kind of bahaviour disturbance and insomnia, euphoria and lack of insight etc. Pathologically, loss of neurons mainly in the cerebral cortex, appearance of Alzheimer's neurofibrillary tangles in the Ammon's horn, cerebral cortex, and hypothalamus, brain stem nuclei such as basal nucleurs of Meynert, locus coeruleus (adrenergic neuron) and raphe nucleus (serotonergic neurons), deposition of senile plaques mainly in the cerebral cortex are the main features of Alzheimer brain.