Apraxia of speech (AOS) is an acquired oral motor speech disorder which affects an individual’s ability to translate conscious speech into motor plans, which leads to limited and difficult speech ability. AOS affects willful or purposeful movement patterns, however AOS usually also affects automatic speech. Individuals with AOS have difficulty connecting speech messages from the brain to the mouth.
Children with AOS have problems saying sounds, syllables, and words. This is not because of muscle weakness or paralysis. The brain has problems planning to move the body parts (e.g., lips, jaw, tongue) needed for speech. The child knows what he or she wants to say, but his/her brain has difficulty coordinating the muscle movements necessary to say those words.
What Causes Apraxia of speech?
AOS can be caused by impairment to parts of the brain that control muscle movements and speech. However, identifying a specific region has been controversial. AOS diagnosis has been made in various patients with damage to the left sub-cortical structures, regions of the insula and Broca’s area.
There is something in the child’s brain that is not allowing messages to get to the tongue musculature to produce appropriate speech. In most cases, the cause is unknown. However, possible causes include:
-Genetic disorders or syndromes
-Stroke leads to brain injury(vascular injury and trauma)
What are some of the signs and symptoms of AOS?
Apraxia of speech (AOS) is a neurogenic communication disorder affecting the motor programming system for speech production. Individuals with AOS demonstrate difficulty in speech production, specifically with sequencing and forming sounds. The individual does not suffer from a language deficiency, but has difficulty in the production of language in an audible manner. Notably, this difficulty is limited to vocal speech, and does not affect signed language production. The individual knows exactly what they want to say, but there is a disruption in the part of the brain that sends the signal to the muscle for the specific movement.
General things to look for include the following:
A Very Young Child
- Does not coo or babble as an infant
- First words are late, and they may be missing sounds
- Only a few different consonant and vowel sounds
- Problems combining sounds; may show long pauses between sounds
- Simplifies words by replacing difficult sounds with easier ones or by deleting difficult sounds (although all children do this, the child with apraxia of speech does so more often)
- May have problems eating
An Older Child
- Makes inconsistent sound errors that are not the result of immaturity
- Can understand language much better than he or she can talk
- Has difficulty imitating speech, but imitated speech is more clear than spontaneous speech
- May appear to be groping when attempting to produce sounds or to coordinate the lips, tongue, and jaw for purposeful movement
- Has more difficulty saying longer words or phrases clearly than shorter ones
- Appears to have more difficulty when he or she is anxious
- Is hard to understand, especially for an unfamiliar listener
- Sounds choppy, monotonous, or stresses the wrong syllable or word
Potential Other Problems
- Delayed language development
- Other expressive language problems like word order confusions and word recall
- Difficulties with fine motor movement/coordination
- Over sensitive (hypersensitive) or under sensitive (hyposensitive) in their mouths (e.g., may not like toothbrushing or crunchy foods, may not be able to identify an object in their mouth through touch)
- Children with AOS or other speech problems may have problems when learning to read, spell, and write.
How can you manage Apraxia of Speech?
Research shows the children/patients with AOS have more success when they receive frequent (3-5 times per week) and intensive treatment. Children/patients seen alone for treatment tend to do better than children seen in groups. As the child improves, they may need treatment less often, and group therapy may be a better alternative.
The focus of intervention for AOS is on improving the planning, sequencing, and coordination of muscle movements for speech production. Isolated exercises designed to “strengthen” the oral muscles will not help with speech. AOS is a disorder of speech coordination, not strength.
To improve speech, the child/patient must practice speech. However, getting feedback from a number of senses, such as tactile “touch” cues and visual cues (e.g., watching him/herself in the mirror) as well as auditory feedback, is often helpful. With this multi-sensory feedback, the child can more readily repeat syllables, words, sentences and longer utterances to improve muscle coordination and sequencing for speech.
Practice at home is very important. Families will often be given assignments to help the child progress and allow the child to use new strategies outside of the treatment room, and to assure optimal progress in therapy.
One of the most important things for the family to remember is that treatment of apraxia of speech takes time and commitment. Children with CAS need a supportive environment that helps them feel successful with communication. For children who also receive other services, such as physical or occupational therapy, families and professionals need to schedule services in a way that does not make the child too tired and unable to make the best use of therapy time.
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“Apraxia of Speech”. National Institute on Deafness and Other Communication Disorders. National Institutes of Health. Retrieved 12 April 2012.
Morgan AT, Vogel AP (March 2009). “A Cochrane review of treatment for childhood apraxia of speech”. Eur J Phys Rehabil Med 45 (1): 103–10.
Vargha-Khadem F, Gadian DG, Copp A, Mishkin M (February 2005). “FOXP2 and the neuroanatomy of speech and language” (PDF). Rev. Neurosci. 6 (2): 131–8
Maassen, B. (Nov 2002). “Issues contrasting adult acquired versus developmental apraxia of speech.”. Semin Speech Lang 23 (4): 257–66.