According to multiple sources, including, Bruce Willis has been diagnosed with frontotemporal dementia (FTD), a type of dementia that affects the frontal and temporal lobes of the brain. FTD can cause communication difficulties like aphasia, which is what Willis was originally diagnosed with. It can also affect a person’s behaviors, personality, emotions, and judgment. Aphasia is a symptom associated with dementia and other cognitive disorders that can affect a person’s ability to speak, listen, read, and write. Despite these profound impacts, aphasia doesn’t affect a person’s intelligence.