Thursday, April 14, 2011

What makes Childhood Apraxia of Speech different from other speech disorders?

Note: For the purposes of this discussion I am not going to include speech disorders such as fluency disorders (stuttering) and voice disorders (problems with the quality of the voice). I am going to focus on the speech disorders that affect articulation (how the speech sounds are produced).

Types of Speech Disorders

In order to understand what makes Childhood Apraxia of Speech unique, you first have to understand a little bit about the main types of speech disorders.

Articulation Disorder

A child has an articulation disorder when they have difficulty producing a specific sound correctly. Speech language pathologists see a lot of children who have trouble producing the /r/ sound, the /l/ sound, or the /s/ sound for example. The child may have trouble with more than one sound, but the difficulty is with the specific speech sound. They typically have trouble making the sound any time it comes up. So, you wouldn't typically see a child who can make a /s/ when it is at the beginning of the word, but can't when the /s/ is at the end of the word. To put it simply, an articulation disorder is a disorder at the level of specific sounds.

Usually this kind of problem doesn't impact intelligibility (how easily a stranger can understand them) too much and is relatively easy to treat in therapy. The therapist would work on helping the child learn to make the sound correctly first in isolation, and then at the beginning, middle, and ends of words. They would then move up to working on the sound in phrases, sentences,and eventually conversation. Articulation disorders respond well to being treated once or twice a week in small groups of children who are all working on the same sounds.

Phonological Disorder

A child has a phonological disorder when the speech errors they are making fall into patterns. Let me explain. Make a /k, k, k/ sound out loud. Now make a /g, g, g/ sound. Both of those sounds are made in the back of your mouth with the back of your tongue. Now make a /p, p, p/ sound and a /b, b, b/ sound. Both of those sounds are make in the front of the mouth with your lips pressed together. All of the consonant sounds in our language can be categorized by the place in the mouth in which they are produced and by how they are produced. Some sounds are front sounds and some sounds are back sounds. Some sounds are short and quick (/p/, /b/) while some sounds are long and drawn out (/m/, /sh/). Children with a phonological disorder have trouble with whole categories of sounds. They might take all back sounds and produce them in the front of the mouth so that words with /k/ and /g/ are pronounced with /t/ and /d/ instead. Or they might make a pattern of errors that has to do with syllable shape. They might leave off all consonants at the ends of words. In two syllable words they might always leave off the second syllable. You get the idea. A phonological disorder is not about having difficulty with a specific sound. It's a problem consistently demonstrated as a pattern.

To diagnose a phonological disorder a speech-language pathologist is going to analyze patterns of errors. The more patterns a child has difficulty with the harder they will be to understand. This type of disorder can significantly impact a child's intelligibility and is more difficult to remediate than a simple articulation problem. Children with a phonological order will typically be producing a lot of speech and will usually be able to imitate, they will just be difficult to understand. Their errors will be consistent.

When treating a child with a phonological disorder the speech-language pathologist will treat the patterns rather than specific sounds. The way the SLP structures therapy will be different than with a simple articulation problem and that difference is important if you are going to see the most improvement in the shortest amount of time. A phonological disorder is a significant speech disorder that takes a lot of therapy to address. You can address it in a group setting particularly if you group children together who are making errors with the same patterns.

Expressive Language Delay

I'm just going to touch on this briefly because this is another reason that a very young child might not be talking yet. Language is separated into two broad categories: receptive and expressive. Receptive language is how well you understand the language that you hear. Parents usually have a sense of whether their child understands what they're being told. For example, usually you'd expect a young child to follow simple directions like, "Get your baby." Expressive language is how well a child can formulate what they want to say. You might have a child of normal intelligence who understands everything they hear, seems to have a normal set of speech sounds based upon the sounds you hear when they babble or use the few words they do have, and yet is not expressing themselves normally for their age. In this case you would be seeing an expressive language delay.

Childhood Apraxia of Speech

Childhood Apraxia of Speech is distinct from other kinds of speech disorders. It is not a problem with a specific sound, groups of sounds, or patterns of production. Childhood Apraxia of Speech is a neurological motor planning disorder. The child knows what they want to say (therefore not expressive language delay). The speech structures and muscles are physically capable of making the sounds. The problem is in the planning of the muscle movements necessary to make the sounds and the transitions from one sound to the next.

This brings the scope of the problem to a whole different level. Now you aren't just trying to fix the /s/ sound. You're not even trying to teach a child who is moving all their back sounds to the front to make them in the correct place. You have to help a child learn to program all the sounds and sound combinations. This is a huge task because the way the muscles have to move to produce /ba/ is different than the way they have to move to produce /be/. So you can't just work on a generic /b/.

Because the problem is with motor planning, speech is often very difficult to understand and errors are inconsistent. Often children with Childhood Apraxia of speech are using smaller numbers of consonants and vowels than children with other types of speech disorders. They also tend to have better speech production in words and phrases that have become automatic (like uh, oh or bye, bye) than when trying to say something new. This makes sense because they've practiced the automatic phrases over and over so the motor planning for that specific word or phrase has been learned. These kids often have trouble imitating because they are being asked to produce something new on demand and they have trouble with the motor planning of anything new.

When treating a child with Childhood Apraxia of Speech or suspected Childhood Apraxia of Speech research has shown that the best results are obtained when therapy is intensive (several times a week) and individual (one-on-one). This is because the speech-language pathologist needs to get as many productions as possible during therapy and that is much harder in a group setting.


Academic Categories vs. Real Life Diagnoses

When you look at these four types of speech disorders on paper they seem very distinct and separate from each other. In real life, things are messier. Often a child's speech problem is due to a little bit of this and a little bit of that.

Also, with a very young child or an older child who isn't talking yet there just isn't enough speech to analyze. You can look for some red flags that make you suspect one disorder is more likely than another, but you cannot be sure. The speech-language pathologist has to make an educated guess based on all the information and design the most appropriate treatment plan possible.

4 comments:

  1. I am 30 years old. I was dx with childhood apraxia of speech when I was about 2 1/2 years old. It took seven and a half years of intensive speech therapy for me to have normal speech. Now, people don't even know that I had to have speech therapy when I talk. I have normal speech. My parents dedicated themselves to helping me find the help I needed. I have great respect for speech pathologists.

    ReplyDelete
    Replies
    1. Erin, I was so very encouraged to read your comment! I have a 6 year old child who is in speech therapy. I sometimes wonder if his speech will be "normal". My wish for him is to have an outcome such as yours.

      Delete
  2. This is so helpful & by far the best summary & review of the reasons a child might have a speech delay. Thank you! My son is 28 months & has an expressive speech delay with 2 different assessments, but neither speech pathologist has told me why. He had started group speech twice a week & I really wasn't that impressed with their technique, as it seemed like the therapist uses the same approach for every child no matter their level or dx. It is a lot of indirect speech therapy like my son could get at home from the techniques I have learned to do or from what he would get from a really good preschool. So I really like how you gave specific examples of what a specific d/o looks like & techniques a therapist would use - which makes so much more sense & seems only possible to assess & to treat in an individual setting. Based on what I read, I think my son has a phonological d/o. He consistently drops of the sound at the end of the word- boa for boat for example. But actually I really don't know. Fortunately, my son is getting individual tx now once a week also as I fought for my insurance to reassess him, but Harbor Regional Center has been providing group speech tx twice/week (though it was an outside speech therapist providing services & switching to speech therapist at HRC who would also be providing group speech tx, but seemed to have a more affective approach), so hopefully the individual speech therapist will use specific techniques & evaluate more for a specific d/o.

    A question: would Kaufman cards be helpful for any type of speech d/o? The speech therapist at his group tx would use these with each kid - 15 cards or so per kid, & I didn't like that she would use the same cards - some my son can say just fine & some he could use practice with. So I found a set of the beginners kit for $80 used, normally $200 new. Would this be worth the investment, though my son probably doesn't have apraxia based on what I read. I am really invested in providing the support my son needs at home & would gladly invest in the cards if it can be a tool I can use successfully at home. So far, both therapists says to get them.

    To give you more background: my son is probably at an 18 month level of expressive language though he is hard to understand & his articulation is weak & he drools still though we are working with him on this (tell him chin wet & remind him to pat dry & then point out chin dry & praise & have him use cloth or sport wrist bands & it seems to have improved as he is more aware & swallowing his saliva more, though when he is watching a signing time video, playing/focused intently on a task by himself, he drools a lot. He also is starting to go to OT.) He is hard to understand- if it wasn't said in context- like he says "ba da!" for "big truck!", "da" for "flag" "sa" for star. & he signs as he attempts words or word approx so mommy & daddy can understand him but others couldn't. Though he says many words clearly - probably has 15 words he can say clearly (mama, daddy, lolo, lala, /grandpa & grandma/, meow, up, down, banana...) and maybe another 20 words not clearly but signs or in context we can understand & is also great at environmental sounds - weeeoooo weeeeoooo for fire truck. He has also started recently to say two word combinations- morning to you, more cheese, bye daddy...

    Thanks!
    Mamavivian63@yahoo.com

    ReplyDelete

Web Analytics