Aphasia is a condition caused by damage to areas of the brain that affects a person’s ability to use language correctly.

In aphasia, parts of the brain involved in speaking, reading, writing and comprehending others are damaged, parts that are collectively known as the brain’s language center.

People with aphasia may have problems choosing the right words or correctly assembling words to create coherent sentences. Aphasia can affect a person’s ability to speak, write and understand the words they read or hear.

Causes of aphasia

The brain damage that causes aphasia may occur as a result of several illnesses and these include:

• Stroke – This is the most common cause, with about 1 in 3 stroke victims developing aphasia
• Severe injury to the head
• Brain tumor
• Progressive neurodegenerative diseases such as Alzheimer’s disease

Types of aphasia

There are several types of aphasia. Some of these include:

Wernicke’s aphasia
Also called fluent aphasia, in this form of aphasia a person uses long and complex sentences but the words chosen do not make sense. Often the individual is unaware they have used nonsensical words and can become frustrated at being misunderstood.

Broca's aphasia
This is also called non-fluent expressive aphasia. The person finds speaking difficult and can only form short, stunted sentences, although it is usually possible to understand the gist of what is being said.

Global aphasia
This is a severe form of aphasia affecting all modes of communication including reading, writing, speaking, naming objects and understanding speech.

Aphasia associated with Alzheimer's disease
Also called anomic aphasia, this form of the condition is characterized by a difficulty recalling the name of a person or object. As Alzheimer’s disease progresses, a patient can eventually find it difficult to form sentences and make themselves understood.

Primary progressive aphasia (PPA)
When progressive disease causes aphasia but does not affect memory or other thought processes for a considerable length of time, the aphasia is called PPA.

Aphasia is usually diagnosed by a speech and language therapist who also helps to arrange treatment. Speech and language therapy is the main approach to the treatment of aphasia. Therapy aims to restore language ability as well as helping individuals to develop alternative ways of communicating.

Often, patients recover their language ability to at least some degree, with some making a full recovery. However, in cases of aphasia caused by a progressive neurological condition, the chances of recovery are poor and treatment is focused on assisting individuals with what they can still do and helping them to use other methods of communication.