Who is Charles Bonnet?  He was a Swiss naturalist, philosopher, and biologist (1720-1793) who first described the hallucinatory experiences of his 89-year-old grandfather, who was nearly blind in both eyes from cataracts.   Charles Bonnet...

Alzheimer's Disease International estimates that the number of people living with dementia worldwide - nearly 44 million in 2014 - will almost double by 2030 and more than triple by 2050.

There is no single test that can show if a person has...