Childhood apraxia of speech (CAS) is an uncommon speech disorder in which a child has difficulty making accurate movements when speaking. It's important to know that CAS is just a label for a speech disorder.
To speak correctly, your child's brain has to learn how to make plans that tell his or her speech muscles how to move the lips, jaw and tongue in ways that result in accurate sounds and words. Your child's brain also plans these movements so that he or she speaks with normal speed and rhythm.
In childhood apraxia of speech, the brain struggles to develop plans for speech movement. As a result, children with CAS don't learn accurate movements for speech with normal ease. In CAS, the speech muscles aren't weak, but they don't perform normally because the brain has difficulty directing or coordinating the movements.
Children with childhood apraxia of speech (CAS) may have many speech symptoms or characteristics that vary depending on their age and the severity of their speech problems. CAS can be associated with delayed onset of first words, a limited number of spoken words, or the ability to form only a few consonant or vowel sounds. These symptoms usually may be noticed between ages 18 months and 2 years, and may indicate suspected CAS.
As children produce more speech, usually between ages 2 and 4, characteristics that likely indicate CAS include vowel and consonant distortions; separation of syllables in or between words; and voicing errors, such as "pie" sounding like "bye." Many children with CAS have difficulty getting their jaws, lips and tongues to the correct position to make a sound, and they may have difficulty moving smoothly to the next sound.
Children vary in how quickly their speech improves, but with speech therapy many children with CAS develop understandable speech. Many children with CAS also have language problems, such as difficulty comprehending speech, reduced vocabulary or difficulty with word order. Some symptoms may primarily be seen in children with CAS and can be helpful to diagnose the problem. However, some symptoms of CAS are also symptoms of other types of speech or language disorders. It's difficult to diagnose CAS if a child has only symptoms that are found in both CAS and in other types of speech or language disorders.
Some characteristics, sometimes called markers, help distinguish CAS from other types of speech disorders. Those particularly associated with CAS include:
- Difficulty moving smoothly from one sound, syllable or word to another
- Groping movements with the jaw, lips or tongue to make the correct movement for speech sounds
- Vowel distortions, such as attempting to use the correct vowel, but saying it incorrectly
- Using the wrong stress in a word, such as pronouncing "banana" as "BUH-nan-uh" instead of "buh-NAN-uh"
- Using equal emphasis on all syllables, such as saying "BUH-NAN-UH"
- Separation of syllables, such as putting a pause or gap between syllables
- Inconsistency, such as making different errors when trying to say the same word a second time
- Difficulty imitating simple words
- Inconsistent voicing errors, such as saying "down" instead of "town," or "zoo" instead of "Sue"
Other characteristics are seen in most children with speech or language problems and aren't helpful in distinguishing CAS. Characteristics seen in both children with CAS and in children with other types of speech or language disorders include:
- Reduced amount of babbling or vocal sounds from ages 7 to 12 months old
- Speaking first words late (after ages 12 to 18 months old)
- Using a limited number of consonants and vowels
- Frequently leaving out (omitting) sounds
- Difficult to understand speech
Other speech disorders sometimes confused with CAS
Some speech sound disorders often get confused with CAS because some of the characteristics may overlap. These speech sound disorders include articulation disorders, phonologic disorders and dysarthria.
A child who has trouble learning how to make specific sounds, but doesn't have trouble planning or coordinating the movements to speak, may have an articulation or phonologic disorder. In an articulation disorder, a child has difficulty with specific sounds. He or she may leave out the sound or use another sound in its place. In phonologic disorders, a child has certain sound error patterns, such as difficulty producing sounds in the back of his or her mouth.
Articulation and phonologic disorders are more common than CAS.
Articulation or phonologic speech errors may include:
- Substituting sounds, such as saying "fum" instead of "thumb," "wabbit" instead of "rabbit" or "tup" instead of "cup"
- Leaving out (omitting) final consonants, such as saying "duh" instead of "duck" or "uh" instead of "up"
- Stopping the airstream, such as saying "tun" instead of "sun" or "doo" instead of "zoo"
- Simplifying sound combinations, such as saying "ting" instead of "string" or "fog" instead of "frog"
Dysarthria is a motor speech disorder that is due to weakness, spasticity or inability to control the speech muscles. Making speech sounds is difficult because the speech muscles can't move as far, as quickly or as strongly as normal. People with dysarthria may also have a hoarse, soft or even strained voice, or slurred or slow speech.
Dysarthria is often easier to identify than CAS. However, when dysarthria is caused by damage to certain areas of the brain that affect coordination, it can be difficult to determine the differences between CAS and dysarthria. In some children, both dysarthria and CAS are present.
Childhood apraxia of speech (CAS) has a number of possible causes, but in many cases a cause can't be determined. Doctors often don't observe a problem in the brain of a child with CAS.
CAS may be the result of brain (neurological) conditions or injury, such as stroke, infections or traumatic brain injury.
CAS also may occur as a symptom of a genetic disorder, syndrome or metabolic condition. For example, CAS occurs more frequently in children with velocardiofacial syndrome and galactosemia.
CAS is sometimes referred to as developmental apraxia. However, children with CAS don't necessarily grow out of CAS as they develop. In many children with delayed or developmental disorders, children follow usual patterns in development of speech and sounds, but they develop more slowly than usual. Children with CAS don't make typical developmental sound errors. They need speech therapy to make maximum progress.
Tests and Diagnosis
To evaluate your child's condition, your child's speech-language pathologist will review your child's symptoms and medical history, conduct an examination of the muscles used for speech, and examine how your child produces speech sounds, words and phrases.
Your child's speech-language pathologist will also assess your child's language skills, such as his or her vocabulary, sentence structure and ability to understand speech.
Several tests will help determine if childhood apraxia of speech (CAS) is present and rule out or identify other problems that may be affecting your child's ability to speak. The specific tasks conducted during the evaluation will depend on your child's age, ability to cooperate and the severity of the speech problem.
Diagnosis of CAS isn't based on any single test or observation. It depends on the pattern of problems that are seen.
It's important to identify whether your child shows symptoms of CAS, because CAS is treated differently from other speech disorders. Children with CAS also may have other communication problems.
It can sometimes be difficult to diagnose CAS, especially when a child speaks very little or has difficulty interacting with the speech-language pathologist.
Your child's speech-language pathologist may determine that CAS may be present. However, your child's speech-language pathologist may not be able to definitely diagnose CAS.
Your child's speech-language pathologist often may be able to determine an appropriate treatment approach for your child, even if the diagnosis is initially uncertain.
Tests may include:
- Hearing tests. Your doctor may order hearing tests to determine if hearing problems could be contributing to your child's speech problems.
- Oral-motor assessment. Your child's speech-language pathologist will examine your child's lips, tongue, jaw and palate for structural problems, such as tongue-tie or a cleft palate, or other problems, such as low muscle tone. Low muscle tone usually isn't associated with CAS, but it may be a sign of other conditions.Your child's speech-language pathologist will observe how your child moves his or her lips, tongue and jaw in activities such as blowing, smiling, and kissing.
- Speech evaluation. Your child's ability to say sounds, words and sentences will be observed during play or other activities.Your child may be asked to name pictures to see if he or she has difficulty making specific sounds or speaking certain words or syllables.Your child's speech-language pathologist may evaluate your child's coordination and smoothness of movement in speech during speech tasks. To evaluate your child's coordination of movement in speech, your child may asked to repeat syllables such as "pa-ta-ka" or say words such as "buttercup."If your child can produce sentences, your child's speech-language pathologist will observe your child's melody and rhythm of speech, such as how he or she stresses syllables and words.Your child's speech-language pathologist may help your child be more accurate by providing cues, such as saying the word or sound more slowly or providing touch cues to his or her face.
Treatments and Drugs
Speech-language pathologists may treat childhood apraxia of speech (CAS) with many therapies.
Because there isn't evidence to show that medications effectively treat CAS, speech therapy is the primary treatment for CAS.
Your child's speech-language pathologist will usually provide therapy that focuses on practicing syllables, words and phrases. When CAS is relatively severe, your child may need frequent speech therapy, three to five times a week. As your child improves, the frequency of speech therapy may be reduced.
Children with CAS generally benefit from individual therapy. Individual therapy allows your child to have more time to practice speech during each session.
It's important that children with CAS get a significant amount of practice saying words and phrases during each speech therapy session. Learning to say words or phrases takes children with CAS time and practice.
Because children with CAS have difficulties planning movements for speech, speech therapy often focuses your child's attention to the sound and feel of speech movements.
Speech-language pathologists may use different types of cues in speech therapy. For example, your child's speech-language pathologist may ask your child to listen carefully and watch him or her form the target word or phrase with his or her mouth.
Your child's speech-language pathologist also may touch your child's face as he or she makes certain sounds or syllables. For example, your child's speech-language pathologist may use his or her hands to help your child round his or her lips to say "oo."
No single speech therapy approach has been shown to be most effective for treating CAS, but some important general principles of speech therapy for CAS include:
- Your child's speech-language therapist will focus on speech drills, such as asking your child to say words or phrases many times during a therapy session.
- Your child will be asked to listen to the speech-language pathologist and to watch his or her mouth as he or she says the target word or phrase. By watching the speech-language pathologist's mouth, your child also sees the movements that go along with the sounds.
- Your child will most likely practice syllables, words or phrases, rather than isolated sounds, during speech therapy. Children with CAS need practice making the movements from one sound to another.
- Because many children with CAS distort vowel sounds, your child's speech-language pathologist may choose words for your child to practice that contain vowels in different types of syllables. For example, your child may be asked to say "hi," "mine" and "bite," or "out," "down" and "house."
- If your child has severe CAS, your child's speech-language pathologist may use a small set of practice words at first, and gradually increase the number of words for practice as your child improves.
Speech practice at home
Because speech practice is very important, your child's speech-language pathologist may encourage you to be involved in your child's speech practice at home.
Your child's speech-language pathologist may give you words and phrases to practice with your child at home that he or she has learned in speech therapy. Each home practice session can be short, such as five minutes in length, and you may practice with your child twice a day.
Children also need to practice words and phrases in real-life situations. Create situations where it will be appropriate for your child to say the word or phrase spontaneously. For example, ask your child to say "Hi, Mom" each time mom enters a room. Practicing words or phrases in real-life situations will make it easier for your child to say the practice words automatically.
Alternative communication methods
If your child has a severe speech disorder and can't effectively communicate, alternative communication methods can be very helpful.
Alternative communication methods may include sign language or natural gestures, such as pointing or pretending to eat or drink. For example, your child could use signs to communicate he or she wants a cookie. Sometimes electronic devices, such as electronic tablets, can be helpful in communication.
It's often important to use alternative communication methods early. Using these methods may help your child become less frustrated when trying to communicate. It may also help your child to develop language skills such as vocabulary and the ability to put words together in sentences.
As speech improves, these strategies and devices may no longer be necessary.
Therapies for coexisting problems
Many children with CAS also have delays in their language development, and they may need therapy to address their language difficulties.
Children with CAS who have fine and gross motor movement difficulties in their arms or legs may need physical or occupational therapy.
If a child with CAS has another medical condition, then effective treatment for that condition may be important to improving the child's speech.
Lifestyle and home remedies
You and your family can work with your child at home to improve his or her speech and language skills. Home practice, in addition to your child's speech therapy sessions, may help your child's progress.
Encourage and support your child as he or she practices speech and language skills. Your support can help your child feel that he or she is doing well and improving in his or her communication skills.
If your child is participating in physical or occupational therapy, as well as speech therapy, schedule different types of therapy at various times so that your child doesn't become too tired from therapy.