What is aphasia?
Aphasia is a disorder where you have problems speaking or understanding what other people say. It usually happens because of damage to part of your brain but can also happen with conditions that disrupt how your brain works. There are also multiple types of aphasia. The location of the damage in your brain determines the type of aphasia you have.
This condition is almost always a symptom of another problem, such as a stroke or traumatic brain injury. It can also happen as a temporary effect of conditions like migraines. Aphasia is often treatable, especially when the underlying condition is treatable or can heal on its own.
What is the difference between aphasia vs. dysarthria, dysphasia or apraxia?
Aphasia is a condition that has a connection or an overlap with several other speech-related disorders and problems, such as dysarthria, dysphasia and apraxia.
- Aphasia: This is the overall term for a brain-connected problem with language abilities, including speaking or understanding other people speaking. Experts use this term for full or partial loss of language abilities.
- Dysphasia (dis-fay-zh-ah): This is an outdated term for partial loss of language abilities from a brain-related problem. Use of this term isn't common in most places. A major part of why it fell out of use is the risk of confusion with the term “dysphagia” (see below).
- Dysphagia (dis-fay-gee-uh): This is the medical term for a problem with swallowing. The ability to swallow relies on specific muscles to push food, liquid, medication, etc. down your throat. Dysphagia can happen with brain or nerve disorders or problems with the muscles themselves.
- Dysarthria: This is when you have trouble speaking because you can’t fully control parts of your mouth, face and upper respiratory system. This can make you speak too loudly or softly, at uneven speeds, mispronounce words, or have unusual changes in pitch (changing between high- or deep-sounding voices).
- Apraxia: This is a problem where you can’t do something even though you have learned how to do it or have done it before. An example would be suddenly not knowing how to use a key to open a locked door, even though you have no problem describing the action and still know how a lock and key work. People with apraxia often have trouble saying words correctly.
Who does it affect?
Aphasia can affect anyone who has damage to the areas of the brain that control your ability to speak or understand other people speaking. It’s more common in middle-aged and older adults — especially because of conditions like stroke — but it can also happen at any age.
How common is this condition?
Aphasia is uncommon, with about 2 million people in the United States having this condition and about 180,000 more developing it each year. It does happen very commonly with certain conditions. An example of this is stroke, where nearly one-third of people with that condition also have some form of aphasia.
How does this condition affect my body?
Because this affects your ability to communicate, people with this condition often feel it's hard for others to understand them. This can cause a range of problems. Some are just minor annoyances, like not being able to ask for a glass of water. Others could become life-threatening misunderstandings, like not being able to tell someone that you’re having symptoms of a stroke.
Symptoms and Causes
What are the symptoms of aphasia?
There are multiple types of aphasia and aphasia-like conditions. While the symptoms of aphasia have many similarities, there are still some important differences. To understand how aphasia works, it helps to understand a little bit about two specific parts of the brain that work together when you talk:
- Broca’s area: This part of the brain gets its name from the French physician who discovered it controls the muscles you use to speak. It’s part of your frontal lobe, usually on the left side just forward of your temple.
- Wernicke’s area: This part of the brain gets its name from the German neurologist who discovered that it controls your ability to understand and select the right words to use when you talk. It’s part of your temporal lobe, also usually on your left side just above your ear.
These two areas of the brain work together to help you speak. Wernicke’s area processes your understanding of words and picks which ones you use, and then it sends signals to Broca's area. Once Broca’s area knows what words to use, it sends the signals to the muscles you use when you speak.
The main types of aphasia
There are eight main types of aphasia, and experts consider three main factors when determining which kind a person has. Those factors are:
- Fluency. Do they speak smoothly and easily? Does their speech have the right pace, pitch, pronunciation and grammar? Can they also write without difficulty?
- Understanding. Does the person understand what other people are saying? Do they say phrases and sentences that make sense? Can they also read and understand written words?
- Repetition. Does the person have any trouble repeating words, phrases or complete sentences?
Also known as “non-fluent aphasia” or “expressive aphasia,” this is one of the more common forms of this condition. People with Broca’s aphasia usually have the following:
- Loss of fluency. People with Broca’s aphasia struggle to form words. They may repeat words or simple phrases over and over (but struggle to or can’t repeat back something you say to them). People with the most severe cases can’t make any sounds (mutism) or can only make a single sound at a time.
- Understanding is not affected. People with Broca’s aphasia can’t speak, but they can still understand what other people are saying. They also can tell that something is wrong with their ability to speak.
- Struggle with repetition. Broca’s aphasia affects repetition, meaning a person with it might have trouble repeating back words or phrases you say to them.
- Other symptoms: Damage to Broca’s area, especially from strokes, often also affects a nearby part of the brain that controls muscles for movement. Because of that, people with Broca’s aphasia are more likely to have at least some paralysis on one side of their body.
Also known as “fluent aphasia” or “receptive aphasia,” this is also a relatively common form of aphasia. People with Wernicke’s aphasia usually have the following:
- Fluent speech. This means that they don’t have any trouble with the physical act of speaking. However, what they say is often confusing or doesn’t make sense. People with this may use the wrong words or make up words. Experts sometimes call this “word salad.”
- Problems with understanding. People with this struggle to understand what others are saying. They might understand very simple sentences, but the more complex the sentence or phrase, the harder it is to understand.
- Struggle with repetition. Wernicke’s aphasia affects repetition, meaning a person with it might struggle to repeat back words or phrases you say to them.
- Other symptoms. Wernicke’s area of the brain is near parts of the brain that affect your sight, so people with this kind of aphasia often have vision problems, too. People with Wernicke’s aphasia also often have anosognosia (an-oh-sog-no-zh-uh), a condition where your brain can’t recognize or process signs of a medical problem you have. That means people with this often don’t know or can’t understand that they have this kind of aphasia.
This is the most severe form of aphasia. It usually involves the following features.
- Loss of fluency. People with global aphasia struggle with the physical act of speaking. People with the most severe forms of this might only make small or isolated sounds, or they might not make any sounds at all (mutism). They also may repeat words or simple phrases over and over (this is a problem with fluency, as they’ll still have trouble repeating back words or phrases you say to them).
- Problems with understanding. People with this struggle to understand what others are saying. They might understand very simple sentences, but the more complex the sentence or phrase, the harder it is to understand.
- Struggle with repetition. Global aphasia affects repetition, meaning a person with it might struggle to repeat back words or phrases you say to them.
- Other symptoms: This kind of aphasia happens with conditions that cause severe brain damage, such as major strokes or head injuries. The damage is usually severe and affects multiple parts of the brain, causing other serious symptoms like one-sided paralysis, blindness and more.
Other forms of aphasia
- Transcortical motor aphasia: This is similar to Broca's aphasia but usually not as severe. A key difference is that people with this don't have a problem repeating back phrases or sentences you say to them.
- Transcortical sensory aphasia: This type is similar to Wernicke's aphasia but usually not as severe. Like with transcortical motor aphasia above, people with this type don't have a problem repeating back what you say. This type of aphasia is common with degenerative brain conditions like Alzheimer’s disease.
- Conduction aphasia: This type of aphasia affects fluency but not understanding. People with this struggle to pronounce words, especially when trying to repeat something you say to them.
- Mixed transcortical aphasia: This aphasia is like global aphasia, except that people with this can still repeat what people say to them.
- Anomic aphasia: People with this kind of aphasia struggle to find words, especially names of objects or words that describe actions. To get around this problem, they often use several words to explain what they mean or non-specific words like "thing" instead.
Other conditions that involve or look like aphasia
- Progressive primary aphasia (PPA). Though it has “aphasia” in the name, this is actually a degenerative brain disorder. People with this condition gradually lose the ability to speak, write, read or understand what others are saying. This is different from injury- or stroke-related aphasia, which doesn’t get worse over time. Different forms of PPA happen with diseases like frontotemporal dementia and Alzheimer’s disease.
- Alexia (word blindness) and agraphia (inability to write). Damage to the parts of your brain that control your ability to speak can also affect your reading and writing abilities. People with alexia can see words but can't recognize or read them. People with agraphia lose the ability to write. These can happen at the same time, but in rare cases, people can have alexia without agraphia, meaning they can write words but then can't read what they wrote.
- Auditory verbal agnosia. This is a condition where a person can hear people speaking but can't recognize that what they hear is other people talking. It happens when there's a disruption in an area of the brain that processes sound or spoken language.
What causes aphasia?
Aphasia can happen with any condition that damages the brain. It can also happen with problems that disrupt your brain’s functions. Possible causes for this include:
- Alzheimer’s disease.
- Brain surgery.
- Brain tumors (including cancer).
- Cerebral hypoxia (brain damage from lack of oxygen).
- Concussion and traumatic brain injury.
- Dementia and frontotemporal dementia.
- Developmental disorders and congenital problems (conditions that you have when you’re born because of a problem while you developed in the womb)
- Epilepsy or seizures (especially if these cause permanent brain damage).
- Genetic disorders (conditions you have at birth that you inherited from one or both parents, such as Wilson’s disease).
- Inflammation of your brain (encephalitis) from viral or bacterial infections, or autoimmune conditions).
- Migraines (this effect is temporary).
- Radiation therapy or chemotherapy.
- Toxins and poisons (such as carbon monoxide poisoning or heavy metal poisoning).
- Strokes or transient ischemic attacks (TIAs).
Is it contagious?
Aphasia is not contagious. It can happen with some contagious conditions, but none of these will definitely cause aphasia.
Diagnosis and Tests
How is it diagnosed?
Diagnosing aphasia takes a combination of a physical exam, asking questions about your history, diagnostic imaging and testing, and more. In some cases, a healthcare provider will recommend running several tests to rule out other conditions or causes that might cause effects similar to those seen with aphasia. Some examples of this include:
- Sensory and nerve function tests. These tests will make sure that hearing problems or nerve damage aren't the cause behind a problem that seems like aphasia.
- Cognitive and memory tests. These tests ensure the problem isn't with the person’s thinking ability or memory.
- Diagnostic and imaging tests. These tests look for lesions or signs of damage to the relevant part of the brain.
What tests will be done to diagnose this condition?
Several tests are possible when providers suspect aphasia. In most cases, a speech language specialist can help to determine what type of aphasia — if any — that a person has. The tests may also help with diagnosing what caused the aphasia and may even determine if the cause is treatable and what kind of treatments will work best.
Possible tests include:
- Blood tests (these can look for anything from immune system problems to toxins and poisons, especially certain metals like copper).
- Computerized tomography (CT) scan.
- Electroencephalogram (EEG).
- Evoked potentials test.
- Genetic testing.
- Magnetic resonance imaging (MRI).
- Positron emission tomography (PET) scan.
- Spinal tap (lumbar puncture).
Management and Treatment
How is aphasia treated, and is there a cure?
Unfortunately, there’s no direct cure for aphasia. However, it’s usually treatable in some way. The first step in treating aphasia is usually treating the condition that causes it. With conditions like stroke, quickly restoring blood flow to the affected area of the brain can sometimes limit or prevent permanent damage.
In cases where aphasia happens because of a temporary problem, such as from a concussion, migraine, seizure or some kind of infection, aphasia is often temporary, too. The aphasia usually gets better or goes away entirely as you recover and your brain heals with time and treatment.
For people who have long-term or permanent brain damage, like what happens with severe strokes, speech therapy can sometimes help a person's language abilities. These therapy options can also help a person with improving their understanding of others, and how to compensate for their aphasia. Speech therapy can also involve caregivers and loved ones, so they know how best to communicate with and help you.
What medications or treatments are used?
The medications or treatments for conditions that cause aphasia can vary widely. Because of that, your healthcare provider is the best source of information on the possible treatments that will help you. They can tailor the treatment options to your needs and circumstances. They'll also consider any underlying health conditions or preferences that might impact your care.
Complications or side effects of the treatment
The possible side effects or complications that can happen depend on what caused this condition in the first place and the specific treatments used. Your healthcare provider can explain the potential side effects or complications most likely in your specific case. You can also ask them more about what you can do to limit or even prevent side effects.
How to take care of myself or manage the symptoms?
Aphasia is a sign of damage or serious disruptions in your brain. Most conditions that cause aphasia are severe, and some are life-threatening medical emergencies. Because of that, you shouldn't try to self-diagnose aphasia. If you or someone you're with have aphasia-like symptoms, you should call 911 (or your local emergency services number) to get medical attention immediately.
How soon after treatment will I feel better?
The time it takes to recover from aphasia depends on what caused it, how long it’s likely to last and the treatments involved. Your healthcare provider is the best person to tell you more about the timeline for you to feel better and recover.
How can I prevent aphasia or reduce my risk of developing it?
Aphasia happens unpredictably, so it's not possible to prevent it. However, you can try to prevent conditions that cause it or reduce your risk of developing those conditions. Some of the things you can do include:
- Eat a balanced diet and maintain a healthy weight. Many conditions related to your circulatory and heart health, especially stroke, can damage areas of your brain, causing aphasia. Preventing stroke and similar conditions is a key way to prevent aphasia from happening or reduce your risk of developing it.
- Don’t ignore infections. Eye and ear infections need fast treatment. If these infections spread to your brain, they can become serious or even deadly, and they can cause brain damage that can lead to aphasia.
- Wear safety equipment. Head injuries can cause brain damage that leads to aphasia. Whether you're on the job or on your own time, using safety equipment can help you avoid a brain injury that can lead to aphasia. Examples of safety gear include helmets and seat belts (or other vehicle safety restraints).
- Manage your health conditions. Managing chronic conditions can help prevent other conditions that can cause brain damage and aphasia. Examples of these kinds of chronic conditions include Type 2 diabetes, high blood pressure, epilepsy and conditions that create a risk of a blood clot that could lead to a stroke.
Outlook / Prognosis
What’s the outlook for this condition, and what should I expect?
The outlook for aphasia depends on several factors. Your healthcare provider can tell you what is most likely to happen in your specific case.
In some cases, aphasia is a short-term problem and will go away quickly. For others, it might take weeks or even months for you to recover fully. Unfortunately, aphasia that happens because of permanent brain damage is often a life-long problem. Speech therapy might help improve aphasia symptoms but may not fully reverse this condition's effects.
How do I take care of myself?
There are many ways that people with aphasia can help themselves or work around the effects of this condition.
People who have aphasia can also do the following to take care of themselves:
- See your healthcare provider as recommended. Follow-up care can help monitor your condition and try to limit the effects.
- Follow your provider’s treatment guidance. Examples include taking your medication as prescribed and going to speech therapy (if your provider recommends it).
- Seek out support groups when possible. These kinds of support communities, either in-person or online, can help you learn from others with aphasia. Aphasia is also a communication problem, so people with it often feel isolated or alone. These groups can help you feel connected to others who understand your situation and struggles.
- Look for alternate ways to communicate. For many people with aphasia — especially Broca’s aphasia —communicating through writing is helpful because it relies on parts of the brain that are usually unaffected.
- Technology can help. Mobile devices like smartphones and tablets can help people with aphasia, offering them other ways to communicate without speaking aloud. There are even apps for those devices specifically designed to help people with aphasia (the National Aphasia Association has a "helpful materials" page, including a regularly updated list of recommended apps and devices).
- Carry something that tells others that you have aphasia. An “aphasia ID” or informational card can help make communication easier in situations involving people who don’t know you or that you have this condition.
What can I do to help a loved one who has aphasia?
There are several tips for people who have a loved one with aphasia. Some of these tips can help make your loved one's life easier and help them connect and communicate. Others can encourage their recovery or improve how they adapt to their condition. Some things you can do include:
- Be patient and understanding. If a loved one has aphasia, empower them by giving them time to communicate. Help them feel safe and encouraged. Let them make mistakes without correcting them, and give them time to finish speaking without interrupting or finishing their sentences. Help them if they ask for it but at first, let them try on their own.
- Find ways to connect. Aphasia disrupts the ability to communicate, which often leads to feelings of severe isolation and loneliness. You can make a huge difference if you communicate with your loved one in ways that are easier and more comfortable for them.
- Make it easier for them to communicate. Get their attention before you start talking, maintain eye contact and give them your full attention, and reduce background noise (like turning down the TV) if possible. Offer them alternate ways to communicate like writing, drawing, hand gestures or with smart devices if they prefer, and if doing so helps them.
- Treat them with respect and dignity. People with aphasia can feel embarrassed or ashamed of their struggles with communicating. Treating them with respect and dignity can help with that. If they struggle to understand, you can talk to them using easier-to-understand words or sentences or by using yes/no questions (if that's what they prefer). You should avoid talking down to them or speaking so slowly that it’s insulting or hurtful. You should also avoid talking louder unless they ask you to do that.
When should I seek care?
If you gradually notice you have symptoms of aphasia, you should talk to a healthcare provider as soon as possible. You should also talk to your healthcare provider if you have aphasia symptoms that get worse over time. This is a sign of a degenerative brain disease rather than an injury or damage from conditions like stroke.
When should I go to the ER?
If aphasia symptoms appear suddenly, you should get emergency medical attention. When aphasia symptoms happen quickly or without warning, it can be a sign of stroke or another dangerous condition, so you should call 911 (or your local emergency services number) to get medical attention immediately.
You should also get help if you notice any of the symptoms of stroke (regardless of whether or not they happen along with symptoms of aphasia) in yourself or someone near you. Those symptoms include:
- Weakness, numbness or paralysis on one side of the body.
- Slurred or garbled speech.
- Droop on one side of the face or vision loss in one eye.
- Trouble swallowing.
- Confusion, irritability or agitation.
- Trouble focusing, thinking or remembering.
- Sudden headache that is severe or keeps you from going about your usual activities.
A note from Cleveland Clinic
Aphasia is a condition that affects a person’s ability to communicate with others, making it hard for them to speak or to understand what other people are saying. Because of that, people with it commonly feel lonely, isolated or afraid. While aphasia might go away on its own (especially with treatment of the underlying problems), it’s sometimes a permanent condition. However, people with aphasia can learn to adapt to the condition with the help of speech therapy. Technology also offers new ways to help people with aphasia communicate. That means people living with aphasia can still build connections and communicate with those around them, which means people with this condition can still find ways to communicate and feel understood.
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