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What is aphasia?
What is the difference between aphasia and dysphasia?
What are the signs of aphasia?
Communication support tools
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What is aphasia?

Aphasia is one of three main communication problems that can be caused by stroke.

Aphasia is a complex language and communication disorder resulting from damage to the language centres of the brain. This damage may be caused by:

• A stroke.
• A head injury.
• A brain tumour.
• Another neurological illness.

While stroke isn't the only cause of aphasia, it's by far the biggest. Around a third of people who have a stroke will experience aphasia.

What is the difference between aphasia and dysphasia?

Some people may refer to aphasia as dysphasia. Aphasia is the medical term for full loss of language, while dysphasia stands for partial loss of language. The word aphasia is now commonly used to describe both conditions.

Learn about the different types of aphasia.

Signs of aphasia

While it will be different for everyone, these are some of the more common signs of aphasia:
Problems with speech

• Not being able to say the words they want to say.
• Only being able to say single words, or form very short sentences, like ‘want drink’.
• Missing out words or getting them in the wrong order.
• Getting stuck on a single word and repeating it over and over.
• Saying one word while meaning another, such as ‘milk’ instead of ‘water’, or ‘yes’ instead of ‘no’.
• Not being able to find the right word, even though they can describe what they are thinking of.

Problems understanding
Problems understanding what others are saying may be less obvious. Someone with aphasia might tell you their understanding is fine, but you might notice some signs. For example:

• Needing others to repeat sentences.
• Needing others to use simpler language when they’re talking.
• Finding it difficult to understand when there is background noise or many people talking at once.
• Finding it difficult to follow a conversation on the phone, where you can’t see the other person’s face or body language.
• Having difficulty following instructions.

Problems reading

• Not being able to read text messages or websites on a smartphone.
• Being able to read only headlines in a newspaper but not the main text.
• Not understanding information in letters they receive.
• Sometimes people with aphasia will be able to write, but they might not be able to read back what they have written.
• Sometimes people with aphasia can read words out loud, but might not understand what they have read out loud.

Problems writing
Writing problems can relate to writing on paper and typing on a smartphone or computer.

• Some people may not be able to write or type at all, even single letters.
• Some people might be able to write/type the first letter of a word, but not be able to spell the rest.
• Some people will be able to write/type sentences but might leave out words.
• Writing problems can make it hard to fill in forms, write emails or send texts.

Problems with numbers

• Problems understanding and using both written numbers (‘ten’) and digits (‘10’).
• Difficulty with calculations and understanding information with numbers.
• Problems with telling the time.

It doesn't affect intelligence, as people with aphasia still think in the same way but are unable to communicate their thoughts easily. This can be hard to understand, we've created a video to explain it further.

Communication support tools

Our accessible communication support tools help support you with communication difficulties at home and in the community.

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Explore all communication problems after stroke, including how stroke affects communication and how to have good conversations.