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.
by Tom Weidig