Primary progressive aphasia (uh-FAY-zhuh) is a rare nervous system (neurological) syndrome that affects your ability to communicate. People with primary progressive aphasia can have trouble expressing their thoughts and understanding or finding words.
Symptoms begin gradually, often before age 65, and worsen over time. People with primary progressive aphasia can lose the ability to speak and write, and, eventually, to understand written or spoken language.
People with this condition may continue caring for themselves and participating in daily life activities for several years after the disorder's onset because it progresses slowly.
Primary progressive aphasia is a type of frontotemporal degeneration, a cluster of related disorders that originate in the frontal or temporal lobes of the brain.
Primary progressive aphasia care at Mayo Clinic