What Is Apraxia of Speech?

Apraxia of speech is a language impairment that occurs due to brain damage. The underlying causes of apraxia of speech are usually different for children than for adults. Speech apraxia is difficult to cope with, and speech therapy can help improve communication.

Diagnosis of the underlying cause is crucial, both to help direct treatment for speech difficulties and to treat and prevent further neurological problems.

Apraxia of Speech Symptoms 

Speech apraxia leads to significant difficulties in communicating. This condition usually causes persistent symptoms and typically doesn't change.

People with apraxia of speech are cognitively and physically able to produce words and sentences. Language comprehension should not be affected by apraxia of speech, and words are not slurred in apraxia of speech.

Features of apraxia of speech include the following:

• Distortion of sounds: The sounds of words and phrases are often wrong in speech apraxia. For example, the vowels or consonants might be drawn out for too long.
• Inconsistency in pronouncing words and sounds: The mispronunciation of words with speech apraxia is not necessarily consistent. For example, you could have difficulty with the first part of a word, and the next time you say that word, you might have difficulty with the middle or the end.
• Struggling for words: If you have apraxia of speech, you will work hard to say the words you want to say.
• Errors in speech: You might use the wrong words and phrases if you have apraxia of speech, despite knowing what you mean to say.

Other cognitive or physical problems can often occur with speech apraxia, depending on the underlying cause.

Causes

Speech apraxia is caused by damage to regions in the brain that mediate communication between language regions in the brain and between the left and right hemispheres of the brain.

This can occur with developmental conditions, such as autism, or it may result from harm to the brain, such as from head trauma.

Conditions associated with apraxia of speech include:

• Autism spectrum disorder
• Cerebral palsy
• Stroke
• Head trauma
• Brain tumors
• Brain surgery

These conditions are not always associated with apraxia of speech. But they can sometimes cause damage or dysfunction to regions of the brain that allow communication between the right and left hemispheres—and then they could be associated with speech apraxia.

Diagnosis 

Speech apraxia is diagnosed based on a clinical evaluation, usually by a physician or a speech therapist. A detailed examination of speech and cognitive abilities is necessary to define apraxia of speech and to rule out other disorders that can cause similar speech and language patterns, such as dysarthria and aphasia.

Speech patterns noted in apraxia of speech include the following:

• Phonemic error frequency: This involves assessment of the frequency of mistakes while pronouncing words.
• Distortion error frequency: This is a count of how often sounds are altered during speech.
• Word syllable duration: This involves assessment of the extra time in saying a word, usually due to struggling.

The Apraxia of Speech Rating Scale (ASRS) is one of the ways that speech apraxia can be defined. Healthcare providers can use this scale to communicate with each other and follow the improvement of apraxia of speech with therapy. The ASRS includes 16 components, such as repetition of sounds or inaccurate sounds, that are rated on a scale from zero to four.

If you’ve been diagnosed with speech apraxia or any communication problem, healthcare providers will work to determine the underlying cause. Issues such as childhood neurodevelopmental problems, stroke, brain tumors, or damage from a head injury need to be identified and treated.

Diagnostic testing may include:

• Brain imaging tests: These tests can help identify common causes of apraxia of speech, such as a stroke or head trauma.
• Cognitive testing: These tests may be used as part of the assessment for autism, dementia, or psychiatric conditions, which may be related to speech challenges.
• Blood tests: Medical problems such as infections, electrolyte disturbances, or organ failure may cause communication difficulties.

In addition to diagnosing speech apraxia, your healthcare providers will also work to determine whether you have other neurological deficits that could be caused by the underlying issue causing your speech apraxia. These can include learning difficulties, behavioral problems, or body weakness.

Treatment 

Apraxia of speech is treated with speech therapy. This type of therapy will follow patterns of treatment that are well-established for improving speech and will also provide an individualized treatment plan.

Therapy may need to be ongoing, and the frequency and specific exercises used during your therapy can be adjusted as you improve. For example, if your speech improves substantially, you might be able to work with your speech therapist less frequently, or you may be able to do some speech exercises at home, as directed by your therapist.

Prognosis 

It’s not possible to predict with absolute certainty whether a person will recover from apraxia of speech and how much they might improve. However, there are some diagnostic clues that can help in anticipating the extent of recovery. 

If you or a loved one has apraxia of speech, it can help to know that the ability to participate in speech therapy can lead to better outcomes. If your cognitive function is not affected or is only mildly impaired, this can help you take an active role in your therapy.

Research About Prognosis and Treatment

Stronger connectivity between certain areas of the right and left hemispheres of the brain is associated with better recovery.

For example, one research study showed that early connectivity of the inferior frontal gyrus (an area that processes speech and language) within two weeks after a stroke may be a strong predictor of recovery of apraxia of speech. 

And at six months, lower severity of speech apraxia was associated with stronger connectivity of the anterior insula (which supports subjective feelings) on the right and left hemispheres and the ventral premotor cortex (which is involved in grasping and manipulating objects) of the right and left hemispheres.

This type of connectivity can be identified with metabolic brain testing, which is time-consuming and often impractical. However, this research can help scientists learn about ways to improve treatment for people with apraxia of speech.

Coping 

Living with a language impairment can be difficult. Communication challenges interfere with relationships and day-to-day life. This can require extra effort from family, friends, and everybody else who interacts with a person who has apraxia of speech.

Patience is essential to managing this communication difficulty. It is important to work with your speech therapist in order to identify ways to communicate as you work to recover. This can include using pictures, gestures, and other ways of expressing your needs.

Summary

Apraxia of speech is a type of language impairment that is caused by damage to the brain, either during fetal development, childhood, or adulthood. This condition can occur along with other neurological deficits that are associated with damage to the brain.

There are many different causes, and a diagnosis of the cause is essential for a comprehensive treatment of speech apraxia, as well as any associated physical and cognitive deficits. Speech therapy is the treatment for the speech impairment seen in this condition.