Until recently, the general term used to describe memory-impaired behavior when there is no discernible physical cause was organic brain syndrome. The new terminology used to describe patients over the age of 65 who are confused and disoriented and show intellectual and memory impairment, bizarre behavior, and shallow emotional reactions is senile dementia. Neurobiological experts suggest that senile dementia can be a temporary state that can be treated and reversed or a permanent (irreversible) condition that results from physical changes in the brain.
Familial factors and Down's syndrome (Mongolism) as well as age itself are implicated in the development of Alzheimer's disease. Aging itself can cause damage to the chromosomes, damage that may also be caused by hazards in the environment or by a slow viral infection that spreads from one member of a family to another.
There is a strong association between Down's syndrome, a genetic disease caused by an extra chromosome, and Alzheimer's disease. A statistically significant study indicates that there are similar fingerprint patterns in people with Alzheimer's and Down's syndrome. Furthermore,