Thursday, August 25, 2005

Between speech and language?

What can happen, will happen somewhere sometime! A quote from my old physics professor at university. You can modify the statement to: What works, will break down somewhere sometime! This realisation leads to be a beautiful analogy between body disorders and body functions. For example in the brain, every brain function must give rise to at least one brain disorder. So the spectrum of brain disorders is a reflection of the functions of the brain. So how about PDS?

The intriguing thing is that PDS does not seem to be a fundamental malfunction of language nor of speech. Virtually all people with PDS have the ability to speak completely fluently at times and in certain situations. If you mix their fluent speech samples with samples of normal speakers, I bet with you that a listener will not be able to distinguish between the two groups. So we do have the ability to speak, and we are not like some people who cannot pronounce certain sounds or control their speech rate. Concerning language, no-one to my knowledge has ever shown that people with PDS have clear language deficits (like in dyslexia), but possibly very subtle ones.

But to what brain function does PDS link if not language or speech? My answer is that PDS is not a total breakdown of a brain function, but only an unstable underperforming brain function. Moreover, PDS is probably not about a specific brain function, but about the malfunctioning interplay between different brain functions, probably the integration between different information from different brain regions. In a sense, it is in between speech and language.

1 comment:

Anonymous said...

If someone stutters when with others but not if they speak to themselves, out loud, when alone, then they do not have a structural abnormality of their brain.
It is a naive error to think that the areas lit up, or not, on a PET scan are somehow causal in behaviour, they are associations with the overt behaviour, nothing more.

If someone can speak fluently in one situation then the issue is the meaning that the person attaches to speech in another situation where he does stammer.

Exploration of what the person wants to get over interms of, not just the words, but how they want to appear to themselves and the other, how they see their chance of looking like a fool and the fear of the subsequent unpleasant feeling etc are much more important than scans results. Nervousness can produce interesting phenomena.

People do not stammer when singing and that is taken simplistically as due to better breath control.
Singing is a complex behaviour and breating is only one of the many issues involved: distraction and the meaning of the vocal sound word of the song and the expression etc. while singing is crucial. In a choir ones self esteem is less vulnerable than in a closed meeting or conversation - one is less exposed. Distraction, in itself, when using breathing to control stammering is ignored by researchers.

No one chooses to stammer but sometimes that is the way the sound emerges. Folk just speak stammeringly in some situations.

Forget a structural cause for stammering and don't take drugs to fix a non existent lesion. Stammering isn't an affliction it is a behaviour and therefore is subject to behavioral modification.