Thursday, October 29, 2009

Why do kids starts stuttering?



Over the last days, I was faced with explaining how children start stuttering.

Here is what I would say. First, children start stuttering because the brain regions involved in speech are not working together well, which leads to delays in speech initiation, which is modulated by stress, neurotransmitter levels, general well-being and which may lead to learned secondary behaviours. There are two different reasons why these regions are not working well together: either because some or all of the regions or connections are developing abnormally slow (possibly due to genes or environmental factors unrelated to stuttering in adults) OR there are fundamental structural issues with one or more regions or connections between (due to genes or/and neurological damage due to environmental events like virus infections, head trauma, birth issues). Unfortunately, both causes lead to very similar dysfunctions, namely delays in speech initiation, and though it is currently not possible to distinguish between both and to predict which child will recover. Recovery is probably primarily due to an abnormally slow but eventual development
of theses regions to their full potential, and all regions work well together, and there is no delay of speech initiation anymore, and any learned behaviours are disappearing gradually. However, it is conceivable that also some children with some fundamental structural issues are able to recover in the sense of speaking fluently for all practical purposes. However, these children mostly have relatively mild or moderate structural issues or/and possess other qualities like abnormally high compensatory abilities (e.g. good dual tasks abilities) or ability to behaviourally control minor delays of initiation. Possibly the quality of hearing might play a factor, too. Are abnormally bad "hearer" less able to correct behaviour?

That's my theory. There are a few critical questions. Brain imaging seem to suggest that kids who recover have greater structural abnormalities. Or is this just a different speech setup in the brain for late developers? Can I make this clear distinction into these two types of stuttering? Phenomenologically both are the same in my view, right.

And here is the safe version. We do not know exactly what causes kids to start stuttering, but genetics is involved in some children. Most kids who start stuttering will recover, but we do no know which kid will recover.

13 comments:

Anonymous said...

Just wondering...Is there absolute, conclusive, undeniable research proof (not s/l "professional research") regarding the information you present regarding children? Or is this just what you think?

Tom Weidig said...

No, there is no definite proof. And there will never be the definite proof, because the issue is so complicated and complex.

Take traffic jams or high crime rate, can you ever say exactly what happened?

Given all I/we know about stuttering and about the human brain, the framework I propose is in my view the best approximate way of thinking about the issue. There is no doubt that there are some subtleties involved in some cases but in general I believe that this is the way to think about childhood stuttering.

Or at the very least, it is a correct framework to debate whether it is correct or not.

Anonymous said...

So this is just "The Stuttering Brain's" view? It's not what all of us who stutter are "required" to believe or "know" that it is true because "The Stuttering Brain" says it is the "correct framework"?

If we who stutter don't agree with what "The Stuttering Brain" expounds to be the truth about stuttering, does that make us "Stuttering No Brain's"? Are we allowed to learn what we might believe is our own truth?

I'm just trying to figure out why you believe you are the know it all expert...Not in a "to criticize you" way, but to understand why you think you are the expert.

What makes you the expert you believe you are?

Chad said...

Interesting thoughts, Tom.
My 3 year old daughter recently went through a phase of mild stuttering. She would have delays when she began a sentence, or sometimes get stuck on a word, and even some minor syllable repetition.
I was absolutely and completely terrified that this was the beginning of her stuttering, and panic was beginning to set in for me.
I had no idea what to do, which is odd for me considering the very strong opinions I have about the development of my own stuttering and how it could have been "cured" in my childhood had my parents taken the time to get me the proper help when I was young.
In any event, I did my best not to draw attention to it, knowing the statistics about how common it is in children and how often it goes away on its own.
She still does it occasionally, but the worst of it seems to have passed.
Also note, she was born 2 months premature, so what you are saying about delayed development could be playing a role for her as it has in other areas. I certainly hope it is not genetic.
My biggest fear of having kids was that I would pass along this nightmare of a trait that I have.
Keep up the god work Tom. I enjoy your posts.

Tom Weidig said...

> Are we allowed to learn what we might believe is our own truth?

If you disagree, then say on which statement and why.

Your truth is just your interpretation of what you have been experiencing. It is not necessarily correct.

> What makes you the expert you believe you are?

At the end of the day, it is the strength of an argument that counts. I am putting forward arguments and theories, and you are welcome to give you opinion.

Anonymous said...

As you are welcome to continue to give your, um,..... opinion.

Andrew said...

Dear anonymous,

Must I explain how the internet works? Read. Filter. Repeat.

I have a 2.3 year old who started stuttering overnight. Literally. Maybe in less time than that.

I've been reading like a fiend and keep ending up back on this site so I appreciate the opinions here.

I also do neurodevelopment research (unrelated to stuttering), so I'm biased, but what feels right to me is some contribution from brain wiring having to converge from several different systems.

There isn't more research on brain miswiring because we are still doing it! So, we all must make the most of our opinions and take our best shots.

Andrew said...

Disconnection of speech-relevant brain areas in persistent developmental stuttering
http://www.ncbi.nlm.nih.gov/pubmed/12241779

Millie Aldan said...
This comment has been removed by a blog administrator.
Millie Aldan said...

I have a 2 year old who began stuttering while I was away on a business trip for 5 days. Everyday I spoke to her on the phone and noticed it worsened. Just wandering if anxiety could cause stuttering, does anyone know?

Tom Weidig said...

@Millie: Many kids start stuttering at 2, but most recovered naturally. Anxiety or other emotional reactions might modulate the severity but the fact that she stutters is due to neurobiology which might change to become more adapt for fluent or not.

Kirsten said...

Hi Tom, My 10-year old recently began stuttering about a month ago. He has had speech services since he was 4 for lateral lisp. That issue is mostly resolved but now he has the stuttering. I guess I didn't realize that older children could develop stuttering. Any insight into why this occurs in older children would be greatly appreciated! Also, should I panic and get speech services again right away or ride it out a while longer? I guess, with him being older, I'm concerned about just letting him grow out of it. Thank you!

Tom Weidig said...

Hi Kirsten,

I don't know exactly what happened.

One theory is that his brain was always borderline able to speak fluently. But as he gets older his brain grows and develops further, add to this hormonal changes, it could be slight changes that have now made him cross this border and he is more prone to brain jams. This would then cause him to react and make the symptoms greater. This could also add stress and he gets stressed before speaking, pushing his brain further way from the fluency region. We often perform less well under stress.

I guess you could ask him how he feels. And you could book a session with a therapist specialised in stuttering.