With all three types of primary progressive aphasia, speech and language is affected. Symptoms will vary depending on what type someone has, but all symptoms progress and get worse over time.

Semantic dementia

Over time, people with semantic dementia forget the meaning of words, as well as what objects and concepts are. For example, they may:

  • Have trouble using the right word – often saying another word or using a vague term like ‘thing’. This may start with names and other words they don’t use very often. As time passes, people will also struggle with more common words and often ask what words mean.
  • Forget what every-day or household items, tools and appliances are used for.
  • Talk about things at great length and in a vague or repetitive manner.
  • Find it hard to understand what other people are saying.
  • Have problems reading and spelling.

In the later stages, people tend to say less. Changes in behaviour and personality are more common and occur earlier in semantic dementia than the other types of PPA. For example, people may develop obsessions or have mood swings, or act in ways that may seem strange to others.

Over time as the condition progresses they may find it difficult to recognise people they know, things around the house or familiar sounds. This means they need much more assistance to manage day-to-day life.

Progressive non-fluent aphasia

People with this condition have trouble producing speech and make mistakes in how they say words or sentences. For example, they may:

  • Have trouble producing words, although they know what they want to say. Speaking may take a lot of effort and words may not come out right.
  • Find that words come out in the wrong order or are missed out altogether.
  • Stutter or speak more slowly or hesitantly and be hard to understand.
  • Struggle to use the right grammar when speaking or writing.
  • Find it hard to understand long and complex sentences.

Over time, they may develop other symptoms including:

  • Problems with reading, writing and spelling.
  • Difficulty hearing.
  • Trouble understanding some words.
  • Changes in behaviour and mood, for example becoming agitated or frustrated.
  • Find it harder to make decisions or plans.
  • Trouble with swallowing.
  • Similar symptoms to Parkinson’s disease such as shaking or being unsteady on their feet.

Logopenic aphasia

This form of PPA was identified more recently. People with logopenic aphasia are generally able to speak and understand others but have trouble finding the words they want to use. For example, they may:

  • Have trouble remembering the right word. The person may pause as they try to find the word they want.
  • Speak more slowly and hesitantly and find it hard to say words correctly.
  • Have trouble understanding and remembering more complex verbal information.
  • Experience behavioural symptoms such as frustration and agitation.

As time passes, people can have more problems with their memory and thinking. For example, someone may forget conversations or appointments, become lost, find it hard to work out how much change they need for a bus fare or struggle to use household appliances, like washing machines. These later symptoms are similar to those in Alzheimer’s disease.

You can speak to your doctor if you are concerned about any of the symptoms mentioned.

Someone with PPA may show symptoms of more than one type of PPA at the same time, or as their condition progresses.

With all three types of PPA, problems get worse over time. It becomes harder for people to say what they need to, move about on their own and look after themselves.

Dementia is different for everyone who has it, and the speed it progresses can vary widely. Over time someone with PPA will need more and more care and support until the end of their life.

What is Primary progressive aphasia?

Information in this booklet is for anyone who wants to know more about primary progressive aphasia (PPA). This includes people living with PPA, their carers, families and friends.


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This information was written in April 2021 and is due for review in April 2023. Please contact us if you would like a version with references.

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