What are the Speech Characteristics of Dysarthria?

What is Dysarthria?

Dysarthria is the result of muscle weakness that causes the inability to effectively control the muscles that are required for speech production. An individual with dysarthria produces speech that can appear slurred and difficult to understand. Dysarthria can range in severity, in some cases making speech unintelligible, whereas in others the effects on speech are mild. 

Dysarthria is a collective term that refers to a group of speech disorders that can result from muscle weakness. Individuals with dysarthria have neurological damage that causes the muscles necessary for speech to become weakened. If you or a loved one is struggling to communicate due to dysarthria, help is nearby. Get started with speech therapy by scheduling your free introductory call today.

What Causes Dysarthria?

Dysarthria causes the muscles necessary for speech (often referred to as ‘articulators’) to be weak. Dysarthria does not typically occur alone, which means that dysarthria occurs as the result of another medical condition. Dysarthria can be congenital (present from birth) or can occur following an illness or injury. Some of the most common causes of dysarthria include:

• Stroke
• Traumatic Brain Injury
• Brain Tumor 
• Multiple Sclerosis (MS)
• Amyotrophic Lateral Sclerosis (ALS / Lou Gherig’s Disease)
• Parkinson’s Disease
• Cerebral Palsy

How Does Dysarthria Affect Speech?

Dysarthria makes correctly forming and pronouncing words difficult. This can make it challenging for others to understand the individual when they are speaking. 

Dysarthria can also affect the coordination of movement that is required for respiration, phonation, resonance, and prosody. These are all elements that contribute to the way in which an individual speaks and communicates.

Respiration – the act of breathing air in and out; which powers speech production

Phonation – the act of the air we produce vibrating the vocal cords

Resonance – the way in which the air is shaped by the oral and nasal cavities

Prosody – the intonation and rhythm of speech

What Are the Different Types of Dysarthria?

Individuals can develop different types of dysarthria depending on the area of the brain that sustained the damage.

Spastic Dysarthria

Individuals with spastic dysarthria typically have speech problems that occur simultaneously with generalized muscle weakness and atypical reflexes. Spastic dysarthria is the result of damage to the motor neurons within the central nervous system, which includes the spinal cord.

Flaccid Dysarthria

The hallmark of flaccid dysarthria is difficulty pronouncing consonant sounds. Flaccid dysarthria is caused by damage to the peripheral nervous system (PNS) which connects the brain and spinal cord to the rest of the body.

Ataxic dysarthria

Ataxic dysarthria causes slurred speech and generally poor coordination. This type of dysarthria is caused by damage to the cerebellum which is the part of the brain that is responsible for the reception of sensory information and regulation of movement.

Hypokinetic dysarthria

A breakdown in the brain’s extrapyramidal system results in hypokinetic dysarthria. The extrapyramidal system includes the areas of the brain that are responsible for coordinating subconscious muscle movements. Individuals with this condition typically produce a voice that is quiet, breathy, or monotone. They may also have difficulty beginning sentences, pronouncing consonants, or swallowing. Slurred speech or stuttering, as well as tremors and muscle spasms, are also common. 

Hyperkinetic dysarthria

Hyperkinetic dysarthria occurs due to damage to areas of the brain that are referred to collectively as the basal ganglia. The basal ganglia are involved in a variety of functions, which include involuntary muscle movement. Symptoms of this type of dysarthria include slurred or slow speech, a shaky voice, shortness of breath, muscle spasms, tremors, involuntary movements, and fatigue when speaking. Hyperkinetic dysarthria usually occurs as the result of neurodegenerative diseases, such as Parkinson’s and Huntington’s.

Unilateral Upper Motor Neuron dysarthria

This type of dysarthria is most commonly caused by a stroke or neurosurgery, although other medical conditions such as a tumor or a traumatic brain injury are other potential causes. Individuals with this type of dysarthria are typically easier to understand than those with other forms of dysarthria as it only affects one side of the face. This form of dysarthria is often only present short term. 

Mixed dysarthria

Mixed dysarthria refers to any combination of the above-mentioned types of dysarthria. This condition typically results from the individual suffering from multiple strokes or diseases such as ALS, Wilson’s, and multiple sclerosis (MS). Mixed dysarthria appears relatively frequently and symptoms from multiple categories may be present. 

Whatever the type of dysarthria may be, speech therapy is the best option when seeking to improve communication skills that are affected by this disorder. Getting started is as simple as scheduling your free introductory call! 

What Are the Speech Characteristics of Flaccid Dysarthria?

The hallmark of flaccid dysarthria is general muscle weakness, which affects different muscles, depending on where the damage to the brain was sustained. In cases of flaccid dysarthria, speech can sound “thick” as if the mouth is filled with food, and in more severe cases, speech may be completely unintelligible. 

How Can Speech Therapy Help with Dysarthria?

Treatment for dysarthria through an experienced speech and language pathologist will depend on the type of dysarthria, as well as the severity of the symptoms. Speech therapy for dysarthria may include working on:

Slowing Down the Pace of Speech

Using More Breath to Increase Volume

Improving Muscle Strength

Increasing Movement with the Tongue and Lips

Saying Individual Sounds, Words and Sentences Clearly

Sometimes a speech therapist will help the individual use alternative means of communication such as gestures, writing, or the use of a tablet or computer. 

The speech therapist will also often work with family and caregivers to help them learn ways to support and communicate with the individual. This is important so that those who are supporting and caring for the individual with dysarthria are learning the same methods and techniques. This ensures that the individual will be encouraged to continue working on speech skills between speech therapy appointments. 

While many dysarthria patients achieve successful rehabilitation, it’s important to understand that the degree of recovery depends on the severity and types of dysarthria the individual may have, and in some cases, they might never completely regain their pre-condition communication skills. When treating someone with dysarthria, the goal often isn’t to restore the damaged part of the brain, but instead to establish compensatory methods for communication. Some forms of dysarthria are easier to reverse, particularly those caused by certain medications or by a mild stroke.

Speech therapy is an essential part of support and recovery for an individual struggling to communicate due to dysarthria. Get help for yourself or a loved one by scheduling your free introductory call today!