Which type of dementia is characterized by the early onset of personality changes?

Frontotemporal dementia is characterized by early and significant changes in personality and behavior. This type of dementia primarily affects the frontal and temporal lobes of the brain, which are responsible for personality, judgment, and social behavior. Individuals may exhibit impulsivity, a lack of empathy, or socially inappropriate behaviors, which are often among the earliest symptoms. These changes can precede memory loss, distinguishing frontotemporal dementia from other types, where memory impairment typically occurs first.

In contrast, Alzheimer's disease generally begins with memory loss and cognitive decline rather than immediate personality changes. Lewy body dementia can include personality changes but is more distinctly associated with visual hallucinations and motor symptoms. Vascular dementia often follows strokes or significant vascular changes and typically presents with cognitive impairments related to these events, not primarily with personality alterations. Thus, frontotemporal dementia is uniquely identified by its early manifestation of personality changes, making it the correct choice.