Aphasia: A Common Neurological Condition You’ve Probably Never Heard Of

Aphasia is a neurological condition that occurs due to damage in areas of the brain responsible for comprehension and producing language. It affects around one million Americans, and upwards of 180,000 new cases are diagnosed each year.¹

People experience symptoms based on the area affected, including difficulty remembering sentences and an inability to understand or create coherent sentences.

The condition can appear suddenly or slowly progress over several years. As a result, each person diagnosed with aphasia experiences the condition in a unique way.

While the number of people living with aphasia continues to rise yearly, our awareness of this common condition is still quite limited.

Aphasia is more common than other well-known neurological conditions like Parkinson’s, multiple sclerosis (MS), and muscular dystrophy. However, a 2022 survey from the National Aphasia Association found that while the number of people who had heard about aphasia has increased over the past few years, 33.2% of the people surveyed had still did not know anything about the condition.²

If you or someone you know has been diagnosed with aphasia, finding out more about the condition and its effects could help.

What is aphasia?

Aphasia is a neurological condition that primarily impacts a person’s ability to comprehend or form speech.

It’s mainly associated with injury or damage to the language centers in the brain, which are often found in the left hemisphere.

Aphasia can dramatically impact your ability to participate in regular day-to-day activities. Depending on the area of the brain affected, you might struggle with four primary areas of communication:³

  • Spoken language expression

  • Spoken language comprehension

  • Writing expression

  • Reading comprehension

People with this condition may also struggle with other speech disorders, as well as conditions like dysarthria (poor articulation), apraxia (difficulty initiating speech), and stuttering. This is because it is often caused by additional injuries in the associated areas of the brain.

Combined, these speech and language disorders can make communicating incredibly frustrating and challenging, especially as the diseases progress.

What causes aphasia?

Aphasia is a uniquely personal condition that causes different symptoms from person to person, depending on the affected areas of the brain.

As a condition that can appear suddenly as a result of an injury or develop slowly over time, some of the most common causes of aphasia include:⁴


Stroke is the most common cause of aphasia. An estimated 20–40% of all people who experience a stroke will develop aphasia symptoms.⁵

Some people experience short-term aphasia symptoms shortly after a stroke, depending on its type and severity. They may then go through a recovery period where their symptoms decrease or disappear altogether.

Traumatic brain injury

Brain tissue can be permanently damaged if you experience a traumatic brain injury (from falling, being hit on the head, or from a car accident, for example). An injury that occurs in the brain’s primary language centers could cause the sudden onset of aphasia symptoms.

Brain tumors

A benign or malignant brain tumor — a mass of cells that develops somewhere it shouldn’t — can cause significant damage to your brain and pressure. Even if the tumor is removed, the long-term effects of the damage can cause you to develop aphasia.

Brain surgery complications

There may be a risk of causing aphasia symptoms with surgery carried out in an area close to the brain’s language centers. Your medical team will discuss these risks with you before the surgery.

In most cases, the risk of developing aphasia as a result of brain surgery is relatively low.

Infections of the brain

Infections like bacterial meningitis and encephalitis (inflammation of the brain tissue) have been known to cause aphasia symptoms when left untreated.

Progressive neurological conditions

Dementia is one of the most common progressive neurological conditions. People diagnosed with dementia have a higher risk of developing aphasia during their lifetime.

Fluent versus non-fluent aphasia — what’s the difference?

Aphasia symptoms can differ widely from person to person based on the affected area of the brain. Two broad categories of aphasia have been created to group the types in a more helpful way: fluent and non-fluent aphasia.

Fluent aphasia

People with this type of aphasia may not have much difficulty creating words and speaking. Instead, they may find it challenging to form coherent or sensical sentences. This means they may speak nonsense strings of words or sentences that lack continuity.

Some of the most common forms of fluent aphasia include:⁶

Wernicke’s aphasia

The Wernicke’s area is an area of the brain associated with language comprehension. Damage to this area can cause you to develop a form of aphasia where you struggle to understand the meaning of spoken words.

You might not experience difficulty speaking, but Wernicke’s aphasia could make it difficult for you to make sense to others. Your ability to read and write is often severely impacted too.

Conduction aphasia

Conduction aphasia may cause difficulty with repeating words or phrases that were just spoken to you.

In most cases, people with this form of aphasia can still write, read, speak, and understand concepts, but they are unable to repeat complex sentences or phrases when asked.

Anomic aphasia

Known for being one of the milder forms of aphasia, people with anomic aphasia often struggle to find the specific words they need to voice their opinion or tell stories.

With anomic aphasia, you might be able to understand a conversation and adequately communicate your thoughts, but nouns and verbs might feel like they’re “at the tip of your tongue.” You might describe things more vaguely because you have difficulty finding the right words.

Transcortical sensory aphasia

Commonly caused by significant damage to the brain’s temporal lobe, people with transcortical sensory aphasia struggle to understand the words they hear.

With this form of aphasia, you might still be capable of forming articulate speech, but your sentences may be filled with nonsensical or invented words that are difficult to understand.

Primary progressive aphasia (PPA)

Primary progressive aphasia develops gradually. It’s actually a form of dementia. It causes difficulty expressing thoughts and finding words.⁷

PPA symptoms can start to arise when the communication and language areas of the brain start shrinking. Like other types of dementia, PPA symptoms worsen as the disease progresses.

Non-fluent aphasia

Non-fluent types of aphasia cause symptoms that are more directly associated with difficulty vocalizing thoughts.

In most cases, people with non-fluent aphasia can understand what is said to them, but they cannot vocalize their response in a way that makes sense.

Some of the most common forms of non-fluent aphasia include:⁶

Broca’s aphasia

People with Broca’s aphasia can understand when they are spoken to but have trouble verbalizing their own thoughts. In most cases, people with this form of aphasia struggle to form grammatically correct sentences and may only be able to speak a few words at a time.

You may still be able to read with Broca’s aphasia, but your writing skills may decrease.

Transcortical motor aphasia

Like Broca’s aphasia, the most identifiable characteristic of transcortical motor aphasia is halted and laborious speech.

With this form of aphasia, you might stop and start your speech multiple times when trying to finish a sentence.

Depending on the severity of this condition, this form of aphasia can become very debilitating. It can make it very challenging to understand what the person is saying.

Global aphasia

Global aphasia is the most severe type of aphasia. It is diagnosed when a person has little to no ability to form words and cannot understand spoken or written language.

Global aphasia is caused by significant damage to multiple areas of the brain. Symptoms suddenly appear after a person suffers a stroke or traumatic head injury.

Depending on the nature of the stroke or injury, the person may recover some of their ability to communicate over the following months while they heal. However, it is almost guaranteed that the person will have some form of life-long disability due to brain damage.

Is there a cure for aphasia?

Despite the increasing prevalence of aphasia worldwide, we still don’t have a definitive cure.

However, while there may be no way to completely eradicate symptoms, it is possible to significantly reduce their severity.

The type of aphasia you are diagnosed with will affect your treatment. If you have aphasia due to an underlying medical condition, such as stroke, infection, or a brain tumor, your doctor will first recommend treatment that addresses the underlying cause.

In addition, getting effective treatment for an injury or stroke can help reduce the amount of brain damage, reducing the risk of developing aphasia.

Speech and language therapy to aid communication can help if you have been formally diagnosed with aphasia. It may involve individual computer-aided therapy or small group sessions with a speech and language therapist. This form of therapy is designed to improve a person’s ability to speak, teach new, more manageable ways to communicate and provide emotional support.

Typically, the goal of speech and language therapy is to help someone with aphasia become as independent as possible.

Tips for helping people living with aphasia

These tips can help improve your ability to communicate with someone who is living with aphasia:

  • Ensure you have the person’s full attention before you start speaking to them

  • Remove sources of background noise

  • Speak at a normal volume, but slow your speech

  • Use short and simple sentences

  • Do not change the subject quickly or suddenly

  • Give the person enough time to respond

  • Use yes or no questions whenever possible

  • Do not correct errors to draw attention to poor grammar

  • Bring a notepad and pen to improve communication

Compassion and understanding are always the way forward when talking to someone with aphasia. As frustrating or confusing as it may be for you to interpret what they are saying, it is much more difficult for them — so do your best to be supportive while working at their speed to ensure everyone can leave the conversation feeling heard.

The lowdown

Despite its growing prevalence around the world, aphasia is a condition relatively few people have heard of.

This neurological condition occurs due to damage in areas of the brain responsible for comprehension and producing language. It causes different symptoms for each person who has it, but generally, it creates communication challenges.

There are many different types and possible causes of aphasia. Treatment depends on the area of the brain affected and your symptoms. It may involve speech and language therapy to aid communication and understanding.

  1. Aphasia | NIH: National Institute on Deafness and Other Communication Disorders

  2. Aphasia statistics | National Aphasia Association

  3. Aphasia | American Speech-Language-Hearing Association

  4. Aphasia | MedlinePlus

  5. Aphasia FAQs | National Aphasia Association

  6. Aphasia (2022)

  7. Primary progressive aphasia | University of California San Francisco

Other sources:

Claire Bonneau is a medical writer and certified trauma operating room nurse.

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