What is Dysarthria, Know its Types, Causes, Treatment, Symptoms, Challenges, Complications

Dysarthria is a condition when the muscles that a person uses for speaking weaken or it becomes difficult to control those muscles. This problem is mostly characterized by unclear or slow speech that is difficult to understand by others. Dysarthria is a commonly occurring speech problem that appears due to different types of neurological disorders from any form of injury to the nervous system or as a side-effect of certain medications. Such neurological disorders cause partial or complete facial paralysis leading to weak muscular movements in the throat or poor movement of the tongue.

Simply speaking dysarthria is a motor speech disorder. For the production of speech, certain facial muscles, like masseter, levator labii, orbicularis oris, etc. works. Apart from these muscles, other important parts like tongue, vocal cords, diaphragm, etc. are all moved due to some muscles. The extent of dysarthria depends on which muscles are affected due to neurological disorders.

Dysarthria is classified into different types depending on the types of symptoms shown by the people affected by dysarthria. The most common types of dysarthria are described below –

• Spastic Dysarthria: It is a type of dysarthria that is caused by the injuries to both the sides of upper motor neuron.
• Flaccid Dysarthria: It is caused by the injuries to one or both sides of lower motor neuron.
• Hyperkinetic Dysarthria: It occurs when some parts of basal ganglia are affected, mostly due to formation of lesions.
• Ataxic Dysarthria: It is a type of dysarthria that occurs due to injury to the superior cerebellum and superior cerebellum peduncle.
• Unilateral Upper Motor Dysarthria: It occurs when one edge of the upper motor neuron suffers injury.
• Hypokinetic Dysarthria: Like hyperkinetic dysarthria, this type of dysarthria occurs when some parts of basal ganglia are affected.
• Mixed Dysarthria: It occurs when one or more of the above mentioned dysarthria affect a person.

Signs and symptoms of dysarthria solely depend on the basic cause or the type of dysarthria affecting a person, some of which are as follows:

• Slurred speech, due to which the listener needs time and patience to understand.
• Patient with dysarthria takes much time to deliver a single sentence.
• Some dysarthria patients may speak too loudly, while the others just whisper.
• Rapid speech, whereby it is really tough for the listeners to understand what the dysarthria affected person is saying.
• Inability to control the rhythm and volume of speech.
• Voice may be strained, hoarse or nasal.
• Inability to talk for a long time.
• Difficulty in moving facial muscles and tongue.

Dysarthria is commonly reflected in multiple motor-speech systems; however, in many patients a single motor-speech system may be affected. Severity of the disease ranges from infrequent speech difficulties to speech that is completely garbled.

Common conditions that may cause dysarthria include the following:

• Brain or head injury and brain tumor
• Stroke
• Lyme disease
• Parkinson’s disease
• Multiple sclerosis
• Cerebral palsy
• ALS (Amyotrophic lateral sclerosis), or Lou Gehrig’s disease
• Guillain-Barre syndrome
• Huntington’s disease
• Muscular dystrophy
• Wilson’s disease.

Above list is not exhaustive, but it may include many other causes behind dysarthria, even some types of medications, such as, sedatives, can also cause dysarthria.

People with dysarthria normally experience problems in the following aspects:

• In timing, because they take too much time in speaking.
• As People with dysarthria can’t control their speech, vocal quality doesn’t seem good.
• They can’t even control the pitch and volume of their voice.
• People with dysarthria can’t control the breath while speaking; as a result they can’t complete sentences or words as generally needed in normal verbal communication.
• They can’t apply necessary strength while speaking.

So while speaking with this type of patients, the other person may notice irregular breakdown of articulation, distorted words, unnecessary pauses or no pause at all, etc. Due to this severe communication problem, a patient with dysarthria often faces social difficulties as he or she can’t communicate with family and friends freely. This further may lead to other psychological disorders including depression and ADHD.

Prognosis of dysarthria depends on the cause of the problem and type of dysarthria affecting a patient. In some situations, symptoms of dysarthria may improve, while in other situations the symptoms may remain the same or get worse slowly or quickly.

• Patients with ALS or Lou Gehrig disease in due course lose the ability to speak.
• Patients with Parkinson’s disease or multiple sclerosis also lose the ability to speak.
• Dysarthria caused by brain stroke sometimes reverse, but in many other situations, it is found to get worse.
• Dysarthria caused by medication or due to a surgery to the tongue or voice box is normally improved with therapy.

A speech therapist, expert in speech-language testing normally evaluates the speech of the patient to determine the type of dysarthria he or she has. After getting report from the pathologist, the neurologist treating the patient takes necessary steps to start related treatment.

Besides the pathological testing, the neurologist may ask for the following tests too:

• Imaging Tests: Tests like MRI or CT scan is needed for detailed images of the brain, head and neck. These help to identify the source of the problem.
• Study of Central Nervous System (CNS) for Diagnosing Dysarthria: These help to detect the exact area of the problem. An electroencephalogram is done to measures electrical activity in the brain, nerves and muscular system.
• Pathological Tests: Blood and urine tests are conducted to understand whether any infection is causing such problem.
• Diagnosing Dysarthria with Lumbar Puncture: In this technique, a needle is inserted into the lower back to collect a small sample of cerebrospinal fluid. A lumbar puncture test helps to diagnose the existence of any infections, disorders of the CNS, and malignant tumor in the brain or spinal cord.
• Biopsy of Brain to Diagnose Dysarthria: If it is suspected that a tumor is present in the brain, the doctor may remove a small sample of the brain tissue through surgery to test.
• Neuropsychological Tests: These tests are required to measure the cognitive skills, ability to understand speech, ability to understand reading and writing, and other skills. In fact, dysarthria doesn’t disturb the cognitive skills and understanding of speech and writing.

The treatment completely depends on the source of the issue, type of dysarthria, and severity of symptoms. An SLP (Speech Language Pathologist) works with the patient to improve his or her communication abilities.

Some possible goals of treatment of dysarthria include:

• Rectifying the rate of speech
• Practicing to control breath to support the speech
• Strengthening facial muscles
• Improving tongue and lip movement to enhance the capacity to speak at a stretch
• Improving the pitch so that speech is more clear
• Providing training to the caregivers, family members, and teacher’s to better communicate with the patient.

Patients with dysarthria need to understand their problem and accept the reality. They also need to change their lifestyle to make their day-to-day activities comfortable.

The following steps will help a person with dysarthria to cope with the difficulties more effectively:

• Speaking Slowly to Cope with Dysarthria: This will enable the dysarthria person to pronounce the words clearly. The listeners will also get some more time to understand clearly what they’re hearing.
• Saying in Smaller Lines: Dysarthria patients should use smaller lines and short phrases instead of bigger and complicated sentences.
• Let the Listeners Know the Problem: Wherever necessary letting people know the actual problem will make the environment more comfortable for the dysarthria patient.
• Confirming from the Listener: After saying something important it may be necessary to confirm from the listeners whether they have understood the matter correctly or they need repetition.
• Back up Message: If the communication is something preplanned, then it will be better to prepare a written message and distribute it among the listeners.

It is important for the listener to help the patient to express him or herself more efficiently. Some important tips for the listeners are as follows:

• A listener should pay complete attention to the speaker. The listener should understand that the patient has a problem in speaking, so he needs to provide time to the speaker to express him or herself.
• Communicate with the speaker in a friendly way to keep the dysarthria patient comfortable.
• If the listener doesn’t understand what the speaker has just said, then he should request him or her to repeat the sentence or paragraph once again.
• The listener should never show impatience or use harsh language while speaking with the patient.

Dysarthria impairs the capacity to speak sporadically. It’s a neurological disorder that leads to reduced muscular activities in and around the face. Dysarthria may happen due to many reasons including injury to the brain and side-effects of some medicines. Upgraded diagnostic systems and pathological testing help the doctors to pinpoint the causes and source of the disease in an individual. Some forms of dysarthria due to some debilitating diseases like ALS or Parkinson’s are not reversible, while in many other situations timely treatment may cure the symptoms in due course.