Aphasia is a language disorder ranging from difficulty finding words to a total loss of the ability to express oneself. It is caused by brain damage caused in the majority of cases by a stroke. Recovery depends on the severity of the injury.
What is aphasia?
Aphasia is the medical term for a person who has lost the ability to use or understand their language. It occurs when the brain is damaged, usually with a stroke.
The different forms of aphasia
There are generally two forms of aphasia:
- Fluent aphasia: the person has difficulty understanding a sentence although he can speak easily.
- Non-fluent aphasia: the person has difficulty expressing themselves, although the flow is normal.
Global aphasia
This is the most severe form of aphasia. It results from significant damage to the language areas of the brain. The patient cannot speak or understand spoken or written language.
Broca’s aphasia, or non-fluent aphasia
Also called “non-fluent aphasia”, Broca’s aphasia is characterized by difficulty speaking, and naming words, even though the affected person can understand much of what is being said. They are often aware of their difficulty communicating and may feel frustrated.
Wernicke’s aphasia, or fluent aphasia
Also known as “fluent aphasia,” people with this type of aphasia can express themselves but have trouble understanding what they are saying. They talk a lot, but what they say is meaningless.
Anomic aphasia
People with this type of aphasia have trouble naming specific objects. They are able to speak and use verbs, but they cannot remember the names of certain things.
Causes of aphasia
The most common cause of aphasia is a stroke of ischemic origin (blockage of a blood vessel) or hemorrhagic (bleeding from a blood vessel). In this case, aphasia appears suddenly. Stroke causes damage to the areas that control language in the left hemisphere. According to statistics, about 30% of stroke survivors have aphasia, the vast majority of which are ischemic strokes.
The other cause of aphasia is dementia, which is frequently manifested by progressive language disorders and is called “primary progressive aphasia”. It is found in patients with Alzheimer’s disease or frontotemporal dementia. There are three variant forms of primary progressive aphasia:
- progressive fluent aphasia, characterized by decreased word comprehension.
- progressive logopenic aphasia, characterized by decreased word production and difficulty finding words;
- progressive non-fluent aphasia, characterized primarily by a decrease in language production.
Other types of brain damage can cause aphasia such as head trauma, brain tumor, or infection that affects the brain. In these cases, aphasia usually occurs with other types of cognitive problems, such as memory or confusion problems.
Sometimes temporary episodes of aphasia may occur. These can be caused by migraines, seizures, or a transient ischemic attack (TIA). An IAT occurs when blood flow is temporarily blocked in an area of the brain. People who have had a TIA have an increased risk of having a stroke in the near future.
Who is most affected?
The elderly are the most affected because the risk of stroke, tumors, and neurodegenerative diseases increases with age. However, it can very well affect younger individuals or even children.
Diagnosis of aphasia
The diagnosis of aphasia is quite easy to make, since the symptoms usually appear suddenly, following a stroke. It is urgent to consult when the person has:
- difficulty speaking to the point that others do not understand it;
- difficulty understanding a sentence to the point that the person does not understand what others are saying;
- difficulty remembering words
- problems reading or writing
Once aphasia is identified, patients must undergo a brain scan, usually magnetic resonance imaging (MRI), to find out which parts of the brain are damaged and how severe the damage is.
In the case of aphasia that appears suddenly, the cause is very often a stroke of ischemic origin. The patient should be treated within hours and further evaluated.
Electroencephalography (EEG) may be necessary to detect if the cause is not epileptic.
If aphasia appears insidiously and gradually, especially in the elderly, the presence of a neurodegenerative disease such as Alzheimer’s disease or primary progressive aphasia will be suspected.
Tests done by the doctor will find out which parts of the language are affected. These tests will assess the patient’s ability to:
- Understand and use words correctly.
- Repeat difficult words or phrases.
- Understand speech (e.g. answer yes or no questions).
- Read and write.
- Solve puzzles or word problems.
- Describe scenes or name common objects.
Possible evolution and complications
Aphasia affects the quality of life because it prevents good communication that can affect one’s professional activity and relationships. Language barriers can also lead to depression.
People with aphasia can often relearn to speak or at least communicate to some extent.
The chances of recovery depend on the severity of aphasia which itself depends on:
- the damaged part of the brain,
- the extent and cause of the damage. The initial severity of aphasia is an important factor determining the prognosis of patients with stroke-induced aphasia. This severity depends on the time between treatment and the onset of damage. The shorter the period, the better the recovery.
In the case of stroke or trauma, aphasia is transient, with a recovery that can be partial (for example, if the patient continues to block certain words) or completely complete.
Recovery can be complete when rehabilitation is carried out as soon as symptoms appear.
Symptoms of aphasia
Symptoms depend on the severity of the disorder and the location of the lesion.
Aphasia against the background of a stroke most often develops after blockage of the internal carotid artery. Symptoms of aphasia depend on the location of the lesion in the stroke.
- Repetition of the same words, regardless of the context or situation.
- Use of personal “jargon”
- Mispronunciation
- Difficulty producing sounds
- Replacing one word with another or one sound with another
- Sometimes producing very long sentences that make no sense
- Speaking in short or incomplete sentences
- Use of incomprehensible words
- Difficulty or inability to understand the conversation of others
- Write sentences that don’t make sense
How to prevent aphasia?
The risk of stroke can be minimized by adopting a healthy lifestyle to reduce the risk of cardiovascular risk factors, such as treating hypertension. On the other hand, we have less control over other causes (e.g. head trauma) that can cause aphasia.
Treatments for aphasia
If the brain damage is mild, a person can recover without treatment.
Speech therapy
However, most people benefit from care that is based on speech therapy. It must be started as soon as possible, as soon as symptoms appear, and followed intensively (4 or 5 sessions per week) to hope to regain language and comprehension skills close to normal.
The degree of recovery from aphasia following a stroke is variable and all the more effective if treatment begins just after the onset of brain damage.
Activities such as theater or singing are also good complementary ways to work on communication and expression.
Language retrieval is usually a slow process. While most people are making significant progress, the effectiveness of rehabilitation approaches remains limited.
Group therapy
Participants can practice starting conversations, taking turns expressing themselves, and relearning how to converse in understandable ways.
Computer Assisted Therapy
The use of computer-assisted therapy can be particularly helpful for relearning verbs and word sounds (phonemes).
Medicaments
Some drugs are currently being studied for the treatment of aphasia. These include drugs that can improve blood flow to the brain, improve the brain’s ability to recover, or help replace neurotransmitters that are lacking in the brain. Several drugs, such as memantine and piracetam, have shown promise in small studies. Further studies are needed to confirm these findings before these treatments can be recommended.
Neuromodulation
Numerous studies conducted over more than a decade have shown that non-invasive brain stimulation techniques, namely transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), can facilitate language recovery in patients with aphasia, resulting from stroke or neurodegenerative disease.
TMS creates a magnetic field that allows the generation of current in neurons located in the cortex. This is also the case of tDCS which delivers a very light current in the brain. The two methods differ in that TMS provides local stimulation, whereas conventional tDCS reaches neurons more diffusely.
The eight clinical studies carried out since 2016 focus almost all cases on patients suffering from non-fluent aphasia following stroke. Overall, it appears that patients see their language improve, especially their ability to name objects more easily. These beneficial effects last for two to four months after neurostimulation.
How to deal with an aphasic person?
Here are some tips for communicating with someone with aphasia:
- Simplify your sentences and slow down your pace.
- Give the person time to talk.
- Do not finish sentences or correct mistakes.
- Reduce distraction noises in the environment.
Image Credit: Photo by Andrea Piacquadio from pexels.com
