Frontotemporal lobar degeneration, also known as frontotemporal dementia (FTD), refers to various disorders that cause cell damage and affect the brain. FTD is the fourth most common cause of dementia. The Alzheimer’s Association estimates that 50,000–60,000 people in the United States have FTD, and the majority of patients are between 45 and 65 years old. FTD occurs when the frontal and temporal lobes of the brain shrink. The frontal and temporal lobes are responsible for personality, behavior and language. Due to the shrinkage of the lobes, people living with FTD often experience drastic behavioral or verbal changes before exhibiting signs of memory loss.
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