Anarthria is a severe form of dysarthria. Dysarthria is a motor speech disorder that occurs when someone can’t coordinate or control the muscles used for speaking. People with dysarthria usually have slurred or slowed speech. People with anarthria, however, can’t articulate speech at all. The condition is usually a result of a brain injury or neurological disorder, such as a stroke or Parkinson’s disease.
Anarthria isn’t a problem with understanding language or finding the right words. People with anarthria want to speak, but they’ve lost control over the speech muscles. The muscles affected by anarthria can include muscles in the lips, mouth, tongue, vocal folds, and diaphragm.
Dysarthria is a less severe form of anarthria. People with dysarthria have a limited ability to speak. Their speech may be slurred, slowed, and difficult to understand, or they may only be able to speak softly in a whisper or hoarse voice.
On the other hand, people with anarthria have completely lost their ability to speak.
Both people with anarthria and people with aphasia aren’t able to speak, but for different reasons.
- Aphasia (also called dysphasia) is considered a language disorder. It’s a problem with language understanding. A person with aphasia can move the muscles used to make speech but may not be able to find the right words, put words into a sentence, or use the correct grammar. Strokes are the most common cause of aphasia.
- Anarthria is considered a motor disorder. It’s a problem with the muscles that are used to produce speech. It doesn’t affect a person’s ability to understand language.
It’s possible for people with anarthria to also have aphasia. Both of these conditions can be caused by a brain injury, such as a stroke.
People with anarthria have lost control over the muscles used for speaking. This is typically a result of a neurological disorder or an injury to the brain. Many different parts of the body are involved in speech production. Anarthria can be a result of damage to any of these areas.
Conditions that can result in anarthria include:
- amyotrophic lateral sclerosis (ALS)
- brain tumor
- cerebral palsy
- Bell’s palsy
- Friedreich’s ataxia
- Guillain-Barré syndrome
- Huntington’s disease
- locked-in syndrome
- Lyme disease
- multiple sclerosis
- muscular dystrophy
- myasthenia gravis
- Parkinson’s disease
- traumatic brain injury (TBI)
- Wilson’s disease
- certain infections
- certain medications, such as opioids or sedatives that affect your central nervous system
- injury to the tongue or vocal folds
- paralysis of the facial muscles
The main symptom of anarthria is the complete loss of the ability to speak. A person with anarthria isn’t able to move the muscles of the mouth, face, and respiratory system. They can formulate a thought and intend to speak, but their body is unable to move the muscles that control speech production.
Other symptoms may include:
- limited movement of the tongue, lips, and jaw
- difficulty chewing or swallowing
Anarthria is the severe form of dysarthria, which can be broken down into different types. The type of dysarthria depends on which part of the brain or nervous system is affected. There are six different types of dysarthria:
- Flaccid dysarthria is caused by damage to the cranial nerves or regions in the brain stem and midbrain that control the mouth and throat muscles; people with this type of dysarthria have very weak speech.
- Spastic dysarthria is a result of damage to the upper motor neurons that originate in the cerebral cortex known as the pyramidal tracts; it is characterized by bursts of sounds.
- Ataxic dysarthria occurs due to damage to the pathways that connect the cerebellum with other regions in the brain; it is characterized by disorganized and jumbled speech.
- Hypokinetic dysarthria is usually caused by Parkinson’s disease and results in a rapid pattern of speech.
- Hyperkinetic dysarthria is a result of damage to the basal ganglia; people with this type of dysarthria have a very slow speech pattern.
- Mixed dysarthria is caused by damage to several areas of the nervous system, which results in speech features that are a mix of two or more groups.
Anarthria is typically diagnosed by a speech-language pathologist and a neurologist. The speech-language pathologist will assess your speech to help determine the type of anarthria you have. He or she will observe how you move your mouth, lips, and tongue, and how well you understand language. A neurologist will evaluate you to determine the underlying cause of the anarthria.
Diagnostic tests may include:
- physical examination
- imaging tests, such as magnetic resonance imaging (MRI) or computed tomography (CT) scan to create images of the brain
- electroencephalogram (EEG) to measure activity in your brain
- electromyogram (EMG) to test the electrical activity in the muscles
- nerve conduction studies to measure how quickly an electrical impulse travels through your nerves
- blood tests to test for infections
- urine tests
- lumbar puncture to test the cerebrospinal fluid
- biopsy, if your doctor thinks that a brain tumor is causing your symptoms
- neuropsychological tests to evaluate your cognitive functions
Your treatment will depend on the type of anarthria and the underlying condition you have.
A doctor will likely recommend speech-language therapy. During a visit with the speech-language therapist you may:
- perform exercises in communication
- perform exercises to strengthen muscles involved in speech
- learn breathing exercises
- practice exercises in safe chewing and swallowing
- work on other forms of communication, like computer-assisted communication, drawing, gesturing, and writing
- practice making sounds
If possible, a doctor will also treat the cause of your anarthria. For example, if your symptoms are caused by a brain tumor, your doctor may recommend surgery to remove the tumor, if possible.
The outlook will depend on the cause, location, and severity of brain damage and your overall health. Symptoms can improve, stay the same, or get worse. Many people with anarthria won’t be able to regain their speech, especially those with degenerative conditions or a brain injury.
People with anarthria may become depressed and frustrated due to their inability to communicate. Learning how to compensate for lack of speech can improve their overall quality of life. This may include using drawings, pictures, communication boards, speech-generating devices, computer-assisted devices, and phone communication (for example texting, email, and messaging apps).