Childhood Apraxia of Speech (CAS) is a rare speech disorder occurring in approximately 0.1%-0.2% of children. Childhood apraxia of speech (CAS) is a neurological childhood (pediatric) speech sound disorder in which the precision and consistency of movements underlying speech are impaired in the absence of neuromuscular deficits (e.g. abnormal reflexes, abnormal tone). As such, apraxia of speech can present severe difficulties for children with the disorder.
In this article, we will discuss what Childhood Apraxia of Speech is, what risk factors contribute to CAS, what symptoms may be present in a child with apraxia of speech, how CAS is diagnosed, and common treatment options for CAS.
What is CAS?
Childhood apraxia of speech is a type of speech and language disorder that is present at birth. A child with this condition has problems making sounds correctly and consistently. Apraxia is a problem with the motor coordination of speech, specifically a problem of the brain directing the movements of the mouth to produce intelligible speech. In this way, it's different from aphasia, which is a problem with the use of words.
The speech centers of the brain help plan and coordinate what a child would like to say. These parts of the brain send complex signals to the speech muscles of the face, tongue, lips, and soft palate. Normally, all this signaling works smoothly, and a child can make all the sounds he or she needs.
With childhood apraxia of speech, something in this process goes wrong. The speech muscles seem to work properly, and the child knows what he or she wants to say. However, the brain has trouble working with the muscles to create the movements needed for clear speech.
CAS is also sometimes referred to as “developmental apraxia of speech” and “developmental verbal dyspraxia.” However, Childhood Apraxia of Speech is generally the preferred term for this disorder.
It is important to note that CAS is truly a rare condition, and it occurs more often in boys than girls. Still, despite its rarity, this condition does affect a non-negligible amount of children, and there are a number of organizations that work with children with CAS and their parents to help these children overcome the difficulties of their disorder.
Signs and Symptoms of CAS
Currently, there are no validated diagnostic features that differentiate CAS from other childhood speech sound disorders. However, three segmental and suprasegmental features consistent with a deficit in the planning and programming of movements for speech have gained some consensus among those investigating CAS:
1. Inconsistent errors on consonants and vowels in repeated productions of syllables or words (for example, a child says the same word differently each time he tries to produce it).
2. Difficulty producing longer, more complex words and phrases.
3. Inappropriate intonation and stress in word/phrase production (for example, difficulty with the timing, rhythm, and flow of speech).
It is important to note that none of these signs or symptoms are generally considered necessary or sufficient for determining whether or not a child has CAS. Moreover, the frequency of these and other signs may change depending on task complexity, the age of the child, and the severity of symptoms.
Other researchers, such as Luzzini-Seigel (2017) have identified a number of other characteristics deemed to be present in many of those who have CAS, representing difficulty with the planning and programming movement gestures for speech. These include:
1. Late development of the child's first words and sounds.
2. A decreased sound inventory (for example, a lack of variety of consonant and vowel sounds expected at a certain age).
3. Multiple and/or unusual sound errors.
4. Vowel sound errors.
5. Excessive movements of the mouth or attempting to position the mouth for sound production.
6. Persistent or frequent regression in the number of words produced.
7. Differences in performance of automatic speech (such as "hello" and "thank you") versus voluntary speech. In most cases, voluntary speech is more affected by apraxia of speech.
8. Errors in the order of sound production in words (such as sounds omitted, switched, or added to words and within words).
It is important to note that the presence of error patterns in the child's speech does not necessarily indicate a phonological problem rather than a motoric problem. Many patterns can have either linguistic or motoric bases. For example, a child may consistently reduce consonant clusters either because of a lack of understanding of the phonological rule or because of a motoric inability to sequence consonants.
Moreover, The signs may vary with a child’s age. They also may be mild to severe. A child with a mild case of apraxia may only have trouble with a few speech sounds. A child with very severe apraxia may not be able to communicate very well with speech at all.
Other Speech Disorders Commonly 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, phonological 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 phonological disorder. Articulation and phonological disorders are more common than CAS.
Articulation or phonological speech errors may include:
1. Substituting sounds, such as saying "fum" instead of "thumb," "wabbit" instead of "rabbit" or "tup" instead of "cup"
2. Leaving out (omitting) final consonants, such as saying "duh" instead of "duck" or "uh" instead of "up"
3. Stopping the airstream, such as saying "tun" instead of "sun" or "doo" instead of "zoo"
4. 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.
What Are the Causes of Childhood Apraxia of Speech?
Researchers don't yet understand what might cause childhood apraxia of speech. Some think that it is related to a child’s overall language development. Others think of it as a problem with the brain’s signals to the muscles needed for speech. Imaging tests have not found any real differences in brain structure in children with the condition.
Childhood apraxia of speech may be a part of a larger disorder a child has, such as:
1. Cerebral palsy
5. Certain mitochondrial disorders
6. Neuromuscular disorders
7. Other intellectual disability
The condition may run in families. Many children with the disorder have a family member with a communication disorder or a learning disability.
Testing and Diagnosis for CAS
An accurate diagnosis of childhood apraxia of speech requires a comprehensive speech and language evaluation by a speech-language pathologist (SLP). The SLP will evaluate your child's speech skills and expressive and receptive language abilities while gathering information from your family about how your child communicates at home and in other situations.
It is important that the SLP evaluating your child has experience and expertise in diagnosing and working with childhood apraxia of speech so an accurate diagnosis can be made and other possible diagnoses are ruled out. For example, childhood apraxia of speech is often confused with a severe articulation disorder, since both diagnoses include poor speech intelligibility. Unfortunately, the approach taken to address an articulation disorder is vastly different from the approach for childhood apraxia of speech, and confusing the two could result in reduced therapy gains.
An assessment for childhood apraxia of speech must include an evaluation of your child's expressive and receptive language abilities; many children with this disorder demonstrate deficits in their language skills. In addition, gaps between receptive and expressive language skills, word order confusion, and difficulty with word recall are common in children with apraxia of speech. A thorough assessment of your child's abilities is needed so therapy goals can be developed based on their individual needs.
Treatment Approaches for CAS
According to the American Speech-Language-Hearing Association (ASHA), there are a number of approaches that practitioners take for treating CAS. These include:
1. Motor programming approaches use fine motor learning principles, including the need for many repetitions of speech movements to help the child acquire skills to accurately, consistently, and automatically make sounds and sequences of sounds. These approaches:
provide frequent and intensive practice of speech targets;
focus on accurate speech movement;
include external sensory input for speech production (e.g., auditory, visual, tactile, and cognitive cues);
carefully consider the conditions of practice (e.g., random vs. blocked practice of targets); and
provide appropriate types and schedules of feedback regarding performance.
2. Linguistic approaches for treating CAS emphasize linguistic and phonological components of speech as well as flexible, functional communication. These approaches focus on speech function. They target speech sounds and groups of sounds with similar patterns of error in an effort to help the child internalize phonological rules. It is important to note that linguistic approaches to CAS are intended as a complement to motoric approaches, not as a replacement for them.
3. Combination approaches use both motor programming and linguistic approaches.
4. Rhythmic (prosodic) approaches such as melodic intonation therapy, use intonation patterns (melody, rhythm, and stress) to improve functional speech production. Prosodic facilitation treatment methods use intonation patterns (melody, rhythm, and stress) to improve functional speech production. Melodic intonation therapy is a prosodic facilitation approach that uses singing, rhythmic speech, and rhythmic hand tapping to train functional phrases and sentences. Using these techniques, the clinician guides the individual through a gradual progression of steps that increase the length of utterances, decrease dependence on the clinician, and decrease reliance on intonation.
5. Augmentative and Alternative Communication (AAC) Approaches involve supplementing or replacing natural speech or writing with aided symbols (e.g., picture communication, line drawings, Blissymbols, speech-generating devices, and tangible objects) or unaided symbols (e.g., manual signs, gestures, and finger spelling), as well as sign language. Whereas aided symbols require some type of transmission device, the production of unaided symbols requires only body movements.
How CASRF Helps and How You Can Too
The California Scottish Rite Foundation (CASRF) is a nonprofit organization that is dedicated to helping children with speech and literacy disabilities and deficiencies overcome their obstacles and reach their goals. Helping children with CAS has long been a part of CASRF’s goals, and for years they have been partnering with individuals, universities, education centers, and more to provide services to children suffering from speech disorders like CAS. Moreover, they have made it their mission to provide these life-changing services free of charge, thanks to help from donors.
If you think that your child may be suffering from CAS, then the CASRF is a great organization to reach out to. Moreover, if you would like to help with their cause of providing free treatment and speech therapy to children in need, then you, too, can donate to help make their mission possible.
Key Points Concerning Childhood Apraxia of Speech
CAS is a rare neurological speech disorder that affects the way that the brain communicates and directs mouth movements to produce clear and intelligible speech. Children suffering from CAS face a number of difficulties, and unfortunately, it is not a disorder that a child can simply “grow out of.” For this reason, it is important that children with CAS have access to treatments from Speech-Language Pathology specialists and/or other speech therapists, and it is important that parents of children with CAS have access to information and resources that can help them help their child struggling with CAS.
The CASRF is an organization that has made it its mission to help children struggling with CASRF, but we hope that you can find many resources, support groups, and organizations that can help you and help your child during these trying times.