When Bruce Willis was diagnosed with frontotemporal dementia at the age of 67, it added to the growing awareness that dementia isn’t just one disease. There are hundreds of different types of dementia. When Robin Williams died, we were introduced to Lewy Body Dementia, a form of dementia mainly related to thinking, memory, and movement. Williams’ despair and probable psychological symptoms led to his shocking suicide. Willis, whose career evolved from light comedy in the 1980s television series Moonlighting to action hero, has stayed out of the public eye as his symptoms have progressed. After almost a year of using the term “aphasia” to describe his condition, the star’s family has revealed he has FTD. Frontotemporal dementia is itself divided into two types: behavioral variant FTD (bvFTD), which mainly affects behavior and personality; and primary progressive aphasia (PPA), a group of dementias mainly causing a loss of speech and language abilities. The most common form of dementia is Alzheimer’s Disease, which affects 60% to 70% of those classified as having dementia. But despite popular perception …