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 symptoms vary, depending on which portion of the brain's language area is involved. The condition has three types, which cause different symptoms.

Semantic variant primary progressive aphasia

Symptoms include these difficulties:

  • Comprehending spoken or written language, particularly single words
  • Comprehending word meanings
  • Naming objects

Logopenic variant primary progressive aphasia

Symptoms include:

  • Having difficulty retrieving words
  • Frequently pausing in speech while searching for words
  • Having difficulty repeating phrases or sentences

Nonfluent-agrammatic variant primary progressive aphasia

Symptoms include:

  • Having difficulty forming words
  • Being hesitant and halting in speech
  • Making errors in speech sounds
  • Having difficulty understanding sentences
  • Using grammar incorrectly


Primary progressive aphasia is caused by a shrinking (atrophy) of the frontal, temporal or parietal lobes in the brain, primarily on the left side. The condition affects the language centers in your brain.

Scar tissue and abnormal proteins also might be present, and brain activity might be reduced.

Risk factors

Risk factors for primary progressive aphasia include:

  • Having learning disabilities. A learning disability might put you at somewhat higher risk of primary progressive aphasia.
  • Having certain gene mutations. Rare gene mutations have been linked to the disorder. If several other members of your family have had primary progressive aphasia, you might be more likely to develop it.


People with primary progressive aphasia eventually lose the ability to speak and write, and to understand written and spoken language.

As the disease progresses, other mental skills, such as memory, can become impaired. Some people develop other neurological conditions. With these complications, the affected person eventually will need help with day-to-day care.

People with primary progressive aphasia can also develop behavioral or social problems as the disease progresses, such as anxiety or irritability. Other problems might include blunted emotions, poor judgment or inappropriate social behavior.

Primary progressive aphasia care at Mayo Clinic

Dec. 22, 2017
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