DAS is a speech disorder that interferes with a child's ability to correctlypronounce sounds, syllables and words. It is the loss of ability to consistently position the articulators (face, tongue, lips, jaw) for the production of speech sounds and for sequencing those sounds into syllables or words. Generally, there is nothing wrong with the muscles themselves. The child does not have difficulty with non-speech activities performed with the muscles such as coughing, chewing or swallowing. However, the area of the brain that tells the muscles how to move and what to do to make a particular sound or series of sounds is damaged or not fully developed. This makes retrieving the "motor plan" for saying a word difficult.
As a result, even though the child knows what he wants to say, he cannot say it correctly at that particular time. Sometimes he cannot even begin. Either the wrong sound comes out, or many sounds are left out all together. At that particular time, the motor plan is not accessible. These errors are not under the child's voluntary control so he often cannot correct them, even when trying his hardest. Frequently, a child will be able to produce a sound or word at one time and not be able to say is again when he wants to. A parent may hear words when the child is playing alone or when he is angry, but when asked to say the same word, he can't. This can be very frustrating for both the child and the parents.
What Causes DAS?
DAS is a neurologically based speech disorder. It is caused by subtle brain impairment or malfunctioning. No one currently know exactly what this brain impairment is or what causes it. Theories range from supposing the impairment is a very specific small injury or difference in the speech area of the brain to saying that is a very diffuse change that is not possible to isolate.
Although some children with DAS have had specific birth or prenatal injuries or periods without oxygen, most DAS children have nothing in their birth or prenatal histories that would suggest a possible cause of the DAS. It is interesting that there are a great deal of similarities in the histories of children with DAS, however, it has not been shown that any one or any specific combination of factors is responsible for the DAS. At this time, we simply do not know what causes DAS.
What are some of the main characteristics of DAS?
For a young child with DAS, a limited speech sound repertoire is frequently the main characteristic of his speech. This simply means that the child has very few speech sounds that he can use automatically so he frequently uses a simple syllable (such as da) to stand for almost everything.
If the child has gotten to a level where he can use several different consonants and is actually talking, the main characteristic of the DAS is inconsistency. A child with DAS is likely to have inconsistent speech errors and speech capability. For instance, he may be able to say a /p/ sound at the beginning of words as long as the /p/ is followed by an /o/, yet, he may not be able to say it if followed by an /e/. Or, maybe he can only say a /p/ at the beginning of a word if the word also ends in a /p/ as in pop. Another example could be that the child can say a /p/ word just fine by itself, but if there is a /t/ word in front of it, the /p/ becomes a /t/( so two pan is said two tan).
Perhaps he can say short single words well, but as soon as he uses two or three words in a row, he drops all the ending sounds. These inconsistencies can easily lead to confusion on the part of both the child and the parent. The child learns that he cannot trust himself to communicate his ideas well, and the parent may wonder whether the child is just being careless or lazy.
The length of a phrase as an adverse effect on articulation. Generally, the longer the utterance, the worse the speech accuracy. A child may be able to say syllables and short words fairly well but be impossible to understand in phrases or sentences.
Apraxic children are usually better at imitating speech than at saying words spontaneously. If you ask a child to say a words right after you, he is likely to say it more accurately than if he said it without your model.
Anxiety may affect a child's ability to speak well. For all of us, performing is more difficult than talking. Under stress, the ability to retrieve motor plans becomes more challenging. A child may be able to say a word or phrase well in a relaxed setting but, when he is "put on display" and asked to " Tell Grandma...", the plan for saying that word or phrase is not accessible, and the child fails.
Children with DAS may also lose words. Parents frequently report that the child "used to say that, but doesn't anymore". This is another example of the motor plan for a word or phrase being unavailable to the child.
Exactly how often the child should have speech therapy will vary according to the individual needs of each child. Children with CAS who have severely unclear or little speech and are more severely affected will require more therapy than those who have milder apraxia. Typically, experienced SLP’s will suggest that a child with moderate to severe apraxia of speech have 3 – 5 times a week of individual speech therapy. Other considerations may have to do with the extent to which the child will practice at home with their parents or caregivers; how much the child can individually tolerate; how frequently the parents can bring their child to speech therapy, etc.
As a child begins to make progress in their ability to produce speech that is understood by others, the amount and frequency of therapy can be adjusted accordingly. Another consideration will be the extent to which other speech and language issues are present in addition to the apraxia of speech.
Speech therapy for a child in which motor planning and programming (CAS) is felt to be the major contributor to the speech problem will involve a number of “key” principles. This is not to suggest that there is one method that is effective. There are a number of features of speech therapy that appear to be most successful to children with apraxia of speech. These features include:
principles of “motor learning” such as a high degree of practice and repetition, correction and feedback, slowed rate, and a focus on targeted motor placement and productions
Increased sensory input for control of the movement sequences and sensory cueing such as visual, tactile, and kinesthetic cueing; touch cueing; verbal cueing.
use of rhythm and melody
focus on speech sequences versus individual sounds
Many experienced speech-language pathologists use multiple methods and approaches rather than a "one approach fits all" notion, taking many of the methods mentioned above and using them based on the individual child's needs. There is no one "program" that is right for every child with apraxia of speech. Commercial products, programs, or kits can be tools for use in therapy by a SLP who understands the nature of apraxia and how to treat it. However, such programs alone are not the solution.
Children with apraxia of speech reportedly do not progress well in their actual speech production with therapy tailored for other articulation problems or with language stimulation approaches. Additionally, in young children the motor/sensory techniques and repetitions of words and target phrases should be woven into play activities that are highly motivational to them. What experienced therapists and families report is that children with apraxia need frequent one-on-one therapy and lots of repetition of sounds, sound sequences, and movement patterns in order to incorporate them and make them automatic.
In addition, many therapists recommend the use of sign language, picture books, and other means to augment speech in the child who is not clearly understood. This approach may be called "total communication." Having the child pair a vocal word attempt with a sign enhances the chance that the listener will be able to "catch" the communication (if the spoken word isn't understood, perhaps the sign will be). Having others understand the communication can offer the child motivation and the feeling of success in using their voice to communicate.
Many children with apraxia of speech, even at young ages, have some awareness of their difficulty. Providing successful communication experiences only encourages the child. Also, for children with apraxia of speech, signs can become important visual cues to help them know how to place their mouths, etc. in order to produce the desired word. When pairing of spoken word and sign is consistent, the child may come to associate the visual image of the sign with the placement of their articulators. In a few children, sign may not be appropriate. For example, for some children signing might be too distracting or their ability to consistently form a sign may be impaired.
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