Hollywood luminary Bruce Willis is now stepping into a role no scriptwriter could have for him. The real-life struggle with Frontotemporal Dementia.

FTD is considered a distant cousin of Alzheimer’s—it’s its own monster. It targets specific brain areas, your frontal and temporal lobes. And then what? Your personality can flip. Your speech? Muddled.

Don’t mix this up with Alzheimer’s only. In fact, it’s a whole new interruption. 3 Types of FTD

Three types of FTD make the scene. Each one’s a different brand of trouble: Behavioral Variant Frontotemporal Dementia (bvFTD):