Dysarthria is a speech disorder caused by a lack of muscle control that happens when the parts of the brain that control speaking are damaged. It may also be caused by problems that do not involve the brain, like a condition affecting the muscles and nerves in the mouth or throat.
The condition is mainly characterized by slurred speech. It may also cause atypical speech rhythm and voice changes, depending on the type of dysarthria.
Dysarthria itself is not a medical emergency. But sudden dysarthria can be caused by a stroke or brain trauma, and these require urgent medical attention.
In general, dysarthria cannot be cured or reversed. However, it’s possible to improve your ability to speak and communicate using certain therapies.
Read on to learn about the symptoms, types, and treatment of dysarthria.
The type of dysarthria depends on the part of the brain affected. These types include:
Flaccid dysarthria is caused by lower motor neuron damage. This involves the cranial and spinal nerves.
Cranial nerves connect your brain to other areas of your head and neck. Spinal nerves connect your spinal cord to other parts of the body.
In spastic dysarthria, the upper motor neurons on one or both sides of the brain are damaged. This involves areas that control movement.
Unilateral upper motor neuron dysarthria
Unilateral upper motor neuron (UUMN) dysarthria is considered a milder form of spastic dysarthria. It’s also one of the most common types of dysarthria.
Often, it’s caused by a stroke. It involves damage to the upper motor neurons, which control movement.
In ataxic dysarthria, there’s damage to the connections between the cerebellum and other parts of the brain.
Hypokinetic dysarthria is caused by an issue with the basal ganglia control circuit, a type of pathway in the brain. The basal ganglia is the part of the brain that controls motor function.
This type is often associated with Parkinson’s disease, which causes slow movement and rigidity.
Hyperkinetic dysarthria is caused by damage to the basal ganglia control circuit. It’s commonly seen in conditions like Huntington’s disease and Tourette syndrome.
This type of dysarthria mainly causes unpredictable speech production.
Mixed dysarthria occurs when there are two or more types of dysarthria present. One example is spastic-flaccid dysarthria, which is seen in amyotrophic lateral sclerosis (ALS).
Mixed dysarthria is the most common type of dysarthria. The exact features depend on the dysarthrias involved.
The symptoms of dysarthria depend on the type. They can also vary in severity.
In general, dysarthria causes:
- slurred speech
- slow or rapid speech
- irregular rhythm of speech
- overly soft or loud speech
- harsh or breathy voice
- difficulty controlling your tongue or lips
- increased nasal resonance (excess noise coming out of the nose)
- monotone volume or loudness
- difficulty swallowing (dysphagia)
- drooling (due to dysphagia)
- choppy speech made of short phrases
Dysarthria is caused by brain damage. This can occur at birth, like in cerebral palsy.
In other cases, brain damage may be due to injury or illness. Examples include:
- traumatic brain injury
- brain tumors
- acoustic neuroma
- amyotrophic lateral sclerosis (ALS)
- Parkinson’s disease
- Huntington’s disease
- Tourette syndrome
- muscular dystrophy
- Bell’s palsy
- myasthenia gravis
- tongue injury
- medications that affect your central nervous system
Both children and adults can develop dysarthria. However, you may be more likely to develop the condition if you:
- have a high risk of stroke
- have a degenerative brain disease
- have a neuromuscular disease
Drinking excessive amounts of alcohol and using illegal drugs can also cause temporary dysarthria while intoxicated.
Diagnosing dysarthria requires several tests. A healthcare professional will use several methods to diagnose dysarthria, including:
- Medical history. A doctor will examine your medical history to determine the cause. This will also help rule out other causes.
- Physical examination. A physical exam lets your doctor look for signs of injury or brain trauma. It can help test sensation, movement, and vision. It can also distinguish between causes like a stroke or infection.
- Blood and urine tests. Urinalysis and blood tests allow your doctor to check for signs of infection.
- Imaging tests. An imaging test, such as an MRI, can help diagnose neurological conditions.
- Genetic tests. If your doctor suspects a gene mutation, they’ll order a genetic test.
- Speech tests. A speech and language therapist might ask you to make sounds, speak, read words, or count numbers. They’ll examine your speech and mouth.
Generally, dysarthria treatment is just one part of a bigger management plan. That’s because it’s usually caused by an underlying condition.
Dysarthria is treated with speech and language therapy. The goal is to improve your ability to speak and communicate.
This type of therapy is provided by a speech-language therapist or pathologist (SLP). Therapy may involve:
- exercises for improving strength and function of affected muscles
- strategies for speaking slowly
- strategies to learn how to properly over-articulate words
- strategies to learn how to use artificial voice software
- exercises for learning how to control speech volume
Your doctor might also recommend acupuncture or transcranial magnetic stimulation of the brain to stimulate the affected muscles.
If you notice any changes in your speech, contact a speech-language therapist or pathologist. This is especially important if you’re at risk for dysarthria.
You should contact a primary care doctor or speech-language professional if you have:
- slurred speech
- difficulty moving your tongue, lips, or jaw
- difficulty raising your voice
- unexplained changes in your voice
- difficulty swallowing
- difficulty pronouncing certain sounds
Dysarthria can make it difficult to communicate with other people. This can have a negative effect on psychological wellness and social relationships.
In most cases, dysarthria cannot be cured. The exception is dysarthria with a temporary cause, like Bell’s palsy or medication.
However, if you have dysarthria, it’s possible to improve your quality of life and ability to communicate. This requires:
- regular speech-language therapy
- routine checkups with a healthcare professional
- management of underlying conditions
- support from family and friends
The success of treatment also depends on many factors, including:
- your underlying condition
- location and severity of brain damage
- your overall health status
It’s possible for people with dysarthria to have fulfilling, quality conversations with other people. The following strategies can help:
Tips for people with dysarthria
If you have dysarthria, try these techniques:
- Inhale deeply before talking.
- Speak slowly. If needed, say one word at a time.
- Face the person you’re speaking with.
- Speak in short sentences.
- Repeat yourself if you need to.
- Limit or avoid background noise by turning off the television or radio.
- If you’re able, carry a pen and paper and write down words.
Tips for non-affected people
If you do not have dysarthria, here’s what you can do to better communicate with those who do:
- Look at the person when they’re speaking.
- Limit or avoid background noise.
- Give them time to respond. Avoid rushing them.
- Avoid finishing their sentences or correcting words.
- Ask “yes or no” questions to confirm that you’ve heard correctly. For example, you can ask, “Did you ask if I got the mail?”
- Be patient and kind.
Dysarthria is a speech disorder caused by brain damage. It can make it difficult to move your facial and mouth muscles, resulting in slurred speech.
There are many causes of dysarthria, including strokes, traumatic brain injuries, degenerative brain diseases, and medication. Strokes and traumatic brain injuries require immediate medical attention.
Dysarthria treatment involves speech-language therapy. This involves working with a professional speech-language pathologist, who can show you how to improve your ability to communicate.