Aphasia is a language disorder ranging from the difficulty of finding one’s words to a complete 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.
Definition of aphasia?
Aphasia is the medical term for someone 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 trouble understanding a sentence although she can speak easily.
- Non fluent aphasia: the person has difficulty speaking, although the flow is normal.
This is the most serious form of aphasia. It results from a significant damage of the areas of the language of the brain. The patient cannot speak or understand spoken or written language.
Broca aphasia or non-fluent aphasia
Also known as “non-fluent aphasia,” Broca’s aphasia is characterized by difficulty speaking, naming words, even though the person with the disease can understand much of what is said. They are often aware of their difficulty communicating and may feel frustrated.
Wernicke aphasia or fluent aphasia
Also known as “fluent aphasia,” people with this type of aphasia can express them but have trouble understanding what they say. They talk a lot, but their words do not make sense.
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.
The causes of aphasia
The most common cause of aphasia is a cerebrovascular accident (stroke) of ischemic origin (blockage of a blood vessel) or hemorrhagic stroke (bleeding from a blood vessel). In this case, the aphasia appears suddenly. Stroke causes damage in areas that control language in the left hemisphere. According to statistics, about 30% of stroke survivors have aphasia, the vast majority of cases being ischemic stroke.
The other cause of aphasia originates from a dementia that is frequently manifested by progressive language disorders and that it calls “primary progressive aphasia”. It is found in patients suffering from Alzheimer’s disease or front temporal dementias. There are three variant forms of primary progressive aphasia:
- Progressive fluent aphasia, characterized by a decrease in the comprehension of words.
- progressive logopenic aphasia, characterized by diminished word production and difficulty in finding words;
- Progressive non-fluent aphasia, characterized primarily by a decrease in the production of language.
Other types of brain damage can cause aphasia, such as head trauma, a brain tumor, or an infection that affects the brain. In these cases, aphasia usually occurs with other types of cognitive problems, such as memory problems or confusion.
Sometimes, temporary episodes of aphasia can occur. These can be caused by migraines, convulsions or transient ischemic attack (TIA). A TIA 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 the most affected?
Older people are the most affected because the risk of stroke, tumors and neurodegenerative diseases increases with age. However, it can very well affect younger individuals, even children.
Diagnosis of aphasia
The diagnosis of aphasia is fairly easy to make, since the symptoms usually appear abruptly 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 where the person does not understand what others are saying
- difficulty remembering words
- Reading or writing problems.
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 serious 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 evaluated further.
Electroencephalography (EEG) may be necessary to detect if the cause is not of epileptic origin.
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 is suspected.
The tests performed by the doctor will help to know 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 (for example answer questions yes or no).
- Read and write.
- Solve puzzles or word problems.
- Describe scenes or name common objects.
Evolution and complication possible
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 the aphasia which 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 aphasia due to stroke. This severity depends on the time elapsed between the treatment and the occurrence of the damage. The shorter the period, the better the recovery will be.
In the case of a stroke or trauma, aphasia is transient, with a recovery that can be partially (for example, the patient continues to block on certain words) or completely complete.
Recovery can be complete when rehabilitation is performed at the onset of symptoms.
The symptoms of aphasia
The symptoms depend on the severity of the disorder and the location of the lesion.
Aphasia in the context of a cerebrovascular accident develops most often after blockage of the internal carotid artery. The symptoms of aphasia depend on the location of the lesion in stroke.
- Repetition of the same words, whatever the context or situation.
- Use of personal “jargon”
- Bad pronunciation
- Difficulty producing sounds
- Replacing a word by another or a sound by another
- Sometimes producing very long sentences that make no sense
- Speak in short or incomplete sentences
- Use of incomprehensible words
- Difficulty or inability to understand the conversation of others
- Write sentences that do not make sense
How to prevent aphasia?
It is possible to minimize the risk of having a stroke by adopting a healthy lifestyle to reduce the risk of cardiovascular risk factors, for example by treating hypertension. On the other hand, we have less control over other causes (eg head trauma) that can cause aphasia.
Treatments for aphasia
If the brain damage is mild, a person can recover without treatment.
However, most people benefit from care that is based on speech therapy . It should be started as soon as possible, at the onset of symptoms, and followed intensively (4 or 5 sessions per week) to hope to find language skills and understanding close to normal.
The degree of cure of aphasia following a stroke is variable and all the more effective as the 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 recovery is usually a slow process. While most people are making significant progress, the effectiveness of rehabilitative approaches remains limited.
Participants can train to start conversations, take turns speaking, and relearn how to converse in an understandable way.
The use of computer-assisted therapy can be particularly useful for relearning verbs and word sounds (phonemes).
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 recovery capacity, 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.
Many studies conducted for more than a decade have shown that noninvasive brain stimulation techniques, namely transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), can facilitate language recovery in patients with aphasia, due to stroke or neurodegenerative disease.
TMS creates a magnetic field that allows current generation in neurons located in the cortex. This is also the case of the tDCS which delivers a very light current in the brain. The two methods differ in that the TMS provides local stimulation, whereas the so-called conventional tDCS reaches the neurons more diffusely.
The eight clinical studies carried out since 2016 relate in almost all cases to patients suffering from non-fluent aphasia following a stroke. Overall, it appears that patients are seeing their language improve, especially their ability to name objects more easily. These beneficial effects last from 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 errors.
- Reduce distraction noises in the environment.