Thursday, January 10, 2008

Uphill struggle for the environment

I discussed the danger of associating causes to the onset of stuttering. Formulating the wrong questions is also confusing the minds of nearly all parents, and many therapists and researchers, though not all.

First, it is misleading to ask or try to answer the question: What causes stuttering? It is important to disentangle onset of stuttering and lack of recovery from stuttering. The onset of stuttering does not mean onset of life-long stuttering. An adult stutterer needs to go through both onset of stuttering and lack of recovery. If someone asks you about what causes stuttering, you should say: We must ask two questions: first what causes the onset of stuttering, and second what causes some not to recover. The two questions very likely have very different answers.

Second, it is misleading to ask what factors are to be blamed for the non-recovery of some kids. This point might be a bit more subtle. Factors, that cause some not to recover, are not really to be blamed for the non-recovery, but they are just not strong enough to overcome onset of stuttering. Think about overcoming stuttering as climbing the Mount Everest. Are you going to blame the bodies and minds of 99% of the population to cause non-ascent to Mount Everest? No, you rather say that 99% are just not good enough to climb Mount Everest as compared to the Top 1%, and you would re-assure them that they have normal bodies and minds. A better but still not perfect way to formulate the question is what causes most to recover. The question should really by: Under which (exceptional) circumstances are kids able to recover from onset of stuttering?

Let me be a bit more concrete. I will give you my big-picture guess on what is happening, and you can hopefully see why these questions are misleading us. The onset of stuttering is the failure to develop certain standard neural pathways because the construction plans are non-standard due to abnormal genes or because the construction was hampered by a neurological incident like head injury, virus infection, low birth weight. The moment of onset is the moment the system gets its first real test in the same way that your brand new but defective car engine runs smoothly until you hit high speeds on the motorway. There is no or little environmental impact like parenting skills or endured stress, except for the out-of-the-ordinary events like injury or virus infection. The onset is entirely caused by internal factors that mostly happen long time before onset like the genes or like the head injury at age 2. Your car engine has a design fault or a manufacturing problem in the factory long time before you hit the high way. Environment and outside events might make stuttering appear a bit earlier or later, but it would have appeared anyway. You could have hit the highways a week later.

At the onset, stuttering children have abnormal neural pathways which cause them to have dysfluencies to which everyone reacts someone somewhat differently in terms of stuttering symptoms. The latest brain imaging results suggest that all children (even those that later recover) have structural abnormalities. Most kids are recovering but some are not. Why? Here is how I think about it, and I use the same escalator analogy for explaining why matter cannot escape black holes! :-) Think of a downward escalator that you want to walk up. You have to overcome the downwards speed by walking up faster. The downward speed is the difficulty to create a second compensatory pathway related to the magnitude of the neurological abnormality. In order to reach the top of the escalator i.e. to recover from stuttering, you need to have an upward walking speed greater than the escalator's downward speed. The upwards speed is determined by whether the kid does the right things, which depends again on genetics like its brain plasticity, semi-genetics like temperament and purely environmental factors like good parental feedback. The key point is that the kid needs ABOVE AVERAGE compensatory skills and environment, in the same way that you need above-average walking speed to climb up a escalator with a standard speed. So those kids that only have average skills and environment to learn compensation or those who have extreme downward speeds, will fail. The majority who recovers was lucky because either the escalator had a slow downward speed which was well compensated by their average skills and environment, or the escalator had a serious downward speed but they had exceptional compensatory skills. For example, girls are more likely to recover because they have a higher ability to compensate. So finally can you really blame their average skills and their environment for stuttering? No.

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