"Primary progressive aphasia (PPA) is a form of cognitive impairment that involves a progressive loss of language function. Language is a uniquely human faculty that allows us to communicate with each other through the use of words. Our language functions include speaking, understanding what others are saying, repeating things we have heard, naming common objects, reading and writing. “Aphasia” is a general term used to refer to deficits in language functions. PPA is caused by degeneration in the parts of the brain that are responsible for speech and language.
PPA begins very gradually and initially is experienced as difficulty thinking of common words while speaking or writing. PPA progressively worsens to the point where verbal communication by any means is very difficult. The ability to understand what others are saying or what is being read also declines. In the early stages, memory, reasoning and visual perception are not affected by the disease and so individuals with PPA are able to function normally in many routine daily living activities despite the aphasia. However, as the illness progresses, other mental abilities also decline.
Adults of any age can develop PPA, but it is more common in people under the age of 65. People with PPA can have a variety of different language symptoms and no two cases are exactly the same."
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Primary Progressive Aphasia