Apraxia of speech (AOS) is a disorder affecting speech. A person with AOS knows what they’d like to say but has difficulty getting their lips, jaw, or tongue to move in the proper way.
To speak, your brain needs to send a message to your mouth. AOS affects the brain pathways involved in planning and coordinating the movements necessary for speech. Because of this, the messages from the brain don’t get through to the mouth correctly.
There are two main types of apraxia of speech:
- Childhood AOS. Present from birth, this type of AOS is diagnosed during childhood. Genetics may play a role in the speech disorder, and it appears to affect boys
more often than girls. - Acquired AOS. This type of AOS can affect anyone, but it most commonly occurs in adults. It’s caused by damage to the brain by something such as a stroke, traumatic brain injury, or brain tumor.
It’s important to remember that AOS is a complex condition, and the severity and symptoms can vary from person to person.
In some people, it may be very mild, with the person only having difficulties with a few sounds or words. In more severe cases, someone may experience great difficulty speaking at all.
Additionally, some people may only have very few symptoms of AOS, while other people may have many symptoms.
Childhood AOS symptoms
These are some childhood AOS symptoms:
- delayed first words
- only being able to produce a few different types of sounds
- syllables or sounds that aren’t put together in the right order
- saying the same word in different ways
- lengthy pauses between sounds or difficulty moving between sounds and syllables
- putting stress on the incorrect syllable of a word or using equal emphasis for all syllables
- putting stress on the incorrect syllable of a word or using equal emphasis for all syllables
- having more trouble with longer words
- having difficulties imitating what another person is saying
- having to move the lips, jaw, or tongue several times in order to make a sound
- appearing to understand spoken language better than they can speak it
Acquired AOS symptoms
Many of the symptoms of acquired AOS are similar to those of childhood AOS. Some of these symptoms can include:
- a slower rate of speech
- distortions of sounds, which can also include sound additions or substitutions
- long pauses between syllables
- placing an equal amount of stress on all syllables in a word
- having to move the lips, jaw, or tongue a few times before speaking
Childhood AOS causes
Researchers do not fully understand what causes childhood apraxia of speech. They think it may be genetic and could be related to overall language development or an issue with the brain’s signals to muscles used for speech.
In some cases, the condition may occur as part of a larger, more complex disorder, such as:
- autism spectrum disorder
- epilepsy
- cerebral palsy
- galactosemia
- a neuromuscular disorder
Childhood AOS may run in families. Many children diagnosed with the condition have a family member with a communication disorder or learning disability. It appears to affect boys more often than girls.
Acquired AOS causes
Acquired AOS can affect anyone, but it occurs most commonly in adults. It is usually caused by an injury that damages the parts of the brain responsible for planning and programming muscle movements necessary for speech.
Here are the most common causes:
- stroke
- traumatic head injury
- tumor or surgical trauma
- neurodegenerative diseases
The condition may present together with other conditions, such as dysarthria (slurred speech) and aphasia, which also causes communication difficulties.
In both children and adults, a professional speech-language pathologist (SLP) works to diagnose and treat AOS. Since the symptoms of AOS may vary from person to person, diagnosis can be difficult.
In addition to taking the person’s medical history, the SLP will look for the presence of groups of symptoms that can be indicative of AOS. They’ll also work to rule out other conditions like:
- aphasia
- muscle weakness
- hearing disorders
Childhood AOS diagnosis
The SLP can use various methods to assess if your child has childhood AOS. Your child’s SLP may:
- ask your child to repeat the same word or syllable several times
- request that your child read from a list of increasingly long words
- assess how your child makes specific vowel or consonant sounds
- listen to your child’s flow of speech to see how they stress different syllables and words or move from one syllable or word to another
- see how well your child’s speech can be understood by others
- give hearing tests to rule out issues with hearing that could be contributing to your child’s speech problem
- assess your child’s lips, tongue, and jaw for any structural issues or muscle weakness
Sometimes in order to make a diagnosis of childhood AOS, the SLP will need to evaluate your child’s speech over a period of time as opposed to in just one session.
Acquired AOS diagnosis
Adults who’ve had a stroke or other type of brain injury may be evaluated for AOS. Similar to the diagnostic process for childhood AOS, the SLP can use a variety of assessments to help them make a diagnosis.
Your SLP may:
- ask you to report any language or communication difficulties you’ve been having
- listen to how you pronounce and apply emphasis to syllables or words
- compare speech you come up with yourself versus speech you’re asked to imitate
- assess the rate at which you communicate verbally
- evaluate how well something you’ve said can be understood
- check your lips, tongue, or jaw for any muscle weakness that may be contributing to your condition
- listen to how your voice sounds — for example, is it harsh, breathy, or weak?
In addition to evaluating your verbal communication skills, the SLP may also ask you to perform tasks that include reading, writing, and nonspeech movements as part of the diagnostic process.
A child with childhood AOS will require treatment, as the condition typically doesn’t improve on its own. However, some cases of acquired AOS may actually improve on their own, which is called spontaneous recovery.
For both children and adults, the treatment for AOS involves speech-language therapy. The specific approach is customized to the individual and takes into account the severity of their condition and the specific difficulties they have with speech.
Speech-language therapy for AOS aims to train your muscles to move properly and to improve the way you put sounds into words. Some examples of exercises in speech-language therapy include:
- asking for the same word or phrase to be repeated multiple times
- practicing saying specific syllables or words to help you learn to move from one sound to another
- having you carefully observe how the therapist’s mouth moves when they say words or phrases
- using visual cues, such as practicing speech in front of a mirror, to remind yourself how to move your mouth to say specific words or phrases
Speech therapy sessions for AOS are typically one-on-one and occur often. As improvement occurs, they may occur less often. Additionally, practice at home with family members is also encouraged.
In more severe cases of AOS, alternative forms of communication may be taught as part of your treatment. This can include things like hand gestures or sign language that you can use to help you communicate with others.
Childhood AOS
In identifying any type of speech or language disorder, it may be helpful to compare the way your child speaks and communicates with the typical milestones for these skills. The American Speech-Language-Hearing Association (ASHA) provides detailed guidelines by age.
Since identifying and treating childhood AOS early can help lower the risk of long-term speech problems, you should be sure to see a doctor if you notice that your child is having problems speaking.
Acquired AOS
If you’re an adult and find that you’re having trouble speaking, be sure to see a doctor. It’s very important that you’re assessed to determine the cause of your condition and to make sure that it doesn’t get worse.
Apraxia of speech is a speech disorder in which you know what you want to say, but you have trouble moving your mouth properly to say it. This isn’t due to muscle weakness or atrophy but instead happens because the signal from your brain to your mouth is disrupted in some way.
There are two types of apraxia of speech — childhood and acquired. Both can be diagnosed and treated by a speech-language pathologist. If you find that you or your child is having trouble speaking, you should be sure to see the doctor to find out the cause of your condition.