History of Dementia.

The term dementia derives from the Latin root demens, which means being out of one's mind. Although the term "dementia" has been used since the 13th century, its mention in the medical community was reported in the 18th century. Even though the Greeks postulated a cerebral origin, the concept was not restricted to senile dementia and included all sorts of psychiatric and neurological conditions leading to psychosocial consequences. In the 19th century, individuals with dementia were recognized as patients, deserving medical care from specialists called alienists, and senile dementia became a medical disease. Subsequently, progresses in neuropathology allowed its fragmentation into different neuropathological conditions. Senile dementia was considered as a distinct entity from Alzheimer's seminal case published in 1906, and was first attributed to a vascular origin. However, from the late 1960s and for 20 subsequent years, Alzheimer's disease became the prototypical senile dementia. Only recently, the term dementia was abandoned for major neurocognitive disorder and the heterogeneity of the syndrome acknowledged again at the phenotypical and molecular levels. We hope a better understanding of this fascinating history will improve scientific research and impose humility towards the complex underpinnings of age-related cognitive decline.