Tuesday, December 15, 2009

Leys Geddes: Sloppy on science

Working on science of stuttering sometimes drives me insane. One hour ago, I had to give a crackpot award to a website that has not clue about stuttering and assumes stuttering is purely psychological. And, then when I was done with the psychos, the neuros needed to be corrected.

Leys Geddes, Chair of the British Stammering Association, writes in Speaking Out:
There are two main things that people need to know: firstly, that the root cause of stammering is a neurological condition, a kind of faulty wiring in the brain, which makes it very difficult for us to control our speech and speak fluently.
In itself, the sentence is probably correct to a first order approximation. However, misleading when considering stuttering as a whole. It's too neuro, and psychos understandably disagree. A lot of stuttering behaviour is learned, re-enforced, and kept alive by an underlying neurological issue. I would even argue that a stuttering event is often not due to the neurology at that precise moment but environmental or internal stimuli triggering stuttering behaviour. And controlling stuttering will mostly involved changing the cognitive behavioural aspects rather than the neuro.

And secondly, that Early Intervention is particularly effective for very young children - because that faulty wiring has not yet kind of hardened up. So, if they are seen by a speech therapist, who is qualified in paediatric stammering, there is about a nine out of ten chance that those at risk of a lifetime of stammering will recover.

There is no evidence for any of the statements:

1) particularly effective? There is no hard evidence for full recovery of any child who would have recovered anyway. No-one ever reads the follow-up study of the flawed Lidcombe study: Three of the children (16%) who had completed treatment successfully had relapsed after 2 or more years of speech that was below 1% syllables stuttered. That's about the recovery rate! Again there is no clear evidence for full recovery. But you could argue that those who would not have recovered anyway have lighter stuttering symptoms. Fine but no cures proven as far as I see. No magic happening.

2) It is not even clear that the natural recoverers ever were at risk of developing stuttering. They might well have recovered anyway and just suffered from temporary stuttering due to a temporary developmental mismatch.

3) And this "faulty wiring not having hardened up" is Alice in Wonderland stuff. The stuff that makes us dream. A messed up brain is a messed up brain, and at best can the brain compensate so that it bypasses the messed up area or optimizes in and outputs and behaves fine overtly.

8 comments:

Leys Geddes said...

Wow, that was a good blast!

Tom, there are scientists arguing right now about climate change, who is responsible for what, and to what degree. And there are scientists and clinicians arguing about stammering too. In both cases, none of them knows everything for certain, but the BSA is one of several leading organisations which believe there is a water tight case for doing the very best we can, rather than nothing.

On the first point, I am thinking of Kate Watkins et al who, on the 10th of October, 2007, published the following in Brain: 'Our data support the conclusion that stuttering is a disorder related primarily to disruption in the cortical and subcortical neural systems supporting the selection, initiation and execution of motor sequences necessary for fluent speech production'. I accept, as do most other people, that many other factors contribute, particularly as time goes by, and these can turn stammering into a kind of syndrome. But none of that detracts from the view that the ROOT CAUSE of stammering is a neurological condition, a kind of faulty wiring in the brain.

On the second point, about the efficacy of Early Intervention, there is a little less science, I grant you. If only Stammering World had more money to do more research we could be more, or less, certain. I know that it may not always be easy to find a speech and language therapist who specialises in paediatric stammering, but there is a growing number in the UK who have the necessary skills. And we are training more because we, and now the Government, believe that there is a sufficiently large body of clinical evidence, and agreement amongst specialists, that Early Intervention with young children who stammer - that is as close to onset as possible - is not only desirable but essential. You and your readers may want to go to www.stammering.org/eccf.html where you will find the BSA's recent report, 'Every Child's Chance of Fluency'. Take a look at the appendices, which summarise the research case for Early Intervention. Daniel Hunter, the therapist who the BSA chose to train SLTs in Early Intervention, has a 98.5% success rate and his achievements were officially recognised in 2008 by the Royal College of Speech and Language Therapists. You should have asked Daniel about this at the recent reception in the place you felt you could not mention. And there were several other leading therapists in the room who would have been happy to say that they have achieved similar results in recent years.

On the third point, about how Early Intervention is effective because the faulty wiring in a young child's brain has not yet hardened up, I think this is a reasonable, short-hand attempt at explaining why the success rate of therapy in terms of overcoming stammering drops away at around the age of six or seven. But we at the BSA are not beholden to any one model, so we will keep an open mind. However, I’m sure you know that this general association between the benefits of Early Intervention and neurological plasticity applies to conditions other than stammering.

I hope that this reply will be given the same prominence as your original article.

Also, Tom, you make a number of points which I think you need to clarify. You say, for example, that ‘a lot of stuttering behaviour is learned, re-enforced, and kept alive by an underlying neurological issue’. You may well be right, but where is your evidence for this? And what, in scientific terms, is ‘a lot of stuttering behaviour’? And, although I probably part-agree with you, where is the evidence for saying that ‘a stuttering event is often not due to the neurology at that precise moment but environmental or internal stimuli triggering stuttering behaviour’? Similarly, can you support the statement that ‘controlling stuttering will mostly involve changing the cognitive behavioural aspects rather than the neuro’? And finally, can you please tell us how this interaction between neurological plasticity and neurological reorganisation works in brain terms?

Anonymous said...

Good response! Can't wait to hear Tom's reply to your questions.

Anonymous said...

Leys,

Your points are directed at Tom, and he should answer them (if he wishes to). But I couldn't help responding to one point in particular.

You quote the following statement: "Our data support the conclusion that stuttering is a disorder related primarily to disruption in the cortical and subcortical neural systems supporting the selection, initiation and execution of motor sequences necessary for fluent speech production"

It makes me laugh because it says nothing. It does not tell us where in the brain to look for a "neurological condition", and yet you use this statement as "water tight" evidence (evidence for what?). Where is this disruption? How did it occur? Was it there at birth, or did it arise during a child's speech development? What tests can be made to locate it and find its nature? It all sounds very half-baked to me. Not even a donkey in a donkey sanctuary would find it satisfactory.

Personally, I believe that there are multiple variants of stuttering, each with different causes - just as there are different causes for baldness, even though bald people look more-or-less the same. One idea that sounds interesting is that stuttering may be due to brain lateralization. As we are repeatedly told, speech is *usually* a function of the brain's left hemisphere. Everybody knows that. But whenever any of us learn anything new - e.g. how to drive a car, or how to play the piano, or how to speak - it is first done in the right hemisphere. Then, as the novel task becomes automatic (i.e. second nature), its function gradually moves to the left hemisphere. It is believed that (at least) some stutterers have a more dominant right hemisphere, and this causes a delay in making speech automatic. The stuttering behaviours are a result of the child trying too hard to speak properly, and speech never quite becomes an automatic task. By the way, I see "speaking" as being different from "talking"; speaking is what we do when we communicate ideas to others, and talking is just what you do when move your mouth and sound comes out (for example, you "talk" when you're alone). Have you noticed that a lot of stutterers seem to be left-handed (or corrected left-handers)? I'm actually right-handed, but was orignially a lefty until I was "corrected" when I was very young. And I know quite a few stutterers like that. Left-handed people have a dominant right-hemisphere.

Another idea (one that really appeals to me) is that stuttering may be due to an overactive amygdala. Actually, that's a simplistic statement; a very detailed description of the hypothesis is given in the following paper:
http://www.veilsofstuttering.com/reactinh.html

These are theories that can be properly discussed and developed and maybe even tested. They are tangible ideas. The statement that you quoted is meaningless and unsatisfactory, and is typical of the rubbish that passes for research in the stuttering world. And I find it very disappointing that you you quote that statement as "water tight" evidence.

By the way, I haven't changed my mind about donating to the BSA.

Leys Geddes said...

Hello, Anon. My original statement was made in the BSA's magazine Speaking Out. It was not aimed primarily at an audience of scientists or therapists and, therefore, I was keen not to get too technical. The thrust of the statement was largely to do with needing to spend less time talking to ourselves and more time talking to the Outside World - people who don't stammer - because, if we don't do this, we won't change anything much for stammerers.

I've used this 'faulty wiring' explanation many times before because it seems to be a very good short hand way of describing the nature of the underlying problem, especially to people who don't stammer and have virtually no knowledge of the condition. I agree that the Watkins research is not conclusive; she says so herself, and there will presumably be more to come. (Have you seen the full report, incidentally?) Anyway, I think that 'faulty wiring' is a fair summary of her findings, so far, and nobody else has objected.

But when I said 'water tight', I was not referring specifically to this research, but to taking responsibility for doing something, rather than nothing, about reducing the amount of stammering in the UK. And the something I was referring to is Early Intervention. Hopefully you looked at the appendices I mentioned, which support this view. But, as I also said, there is not as much purely scientific support as we would like. However, in the UK, a decent number of well trained SLTs are doing the business, and getting great results, but none of them has really stopped to quantify, publish and peer review what they are doing. I guess that’s largely because we have a National Health Service, so there is no need to sell a particular therapy process to others for commercial gain and, what's more, our Government, the main sponsor, has already accepted the benefits of EI.

Personally, I have always felt that the left hand side of my whole head was weaker than the right side. When playing rugby, for example, I would always go into an impact with the right side of my head forward, to protect the left. Yet although I'm right handed, I am fairly good with my left hand. Incidentally, a lot of tennis players and architects are apparently left-handed and this is supposedly connected with a greater understanding of spacial awareness!

I do think it is unfair that Tom's headline 'Leys Geddes gets the science wrong' is now all over the web, but my reply is nowhere. We have a similar issue in the UK with newspapers giving great prominence to their own views and then giving virtually none to the other side of the story, put forward by the person who they have rubbished.

Adrian said...

Leys, as I have stated publicly many times, I greatly respect what you are doing and I think you are one of the stuttering good guys.

But, that said, I also believe the SLT/SLP community has pulled the wool over your eyes in regards to early intervention. I have read the BSA report and I did not find it at all convincing. The fact is we just don't know if early intervention has any effect on stuttering at all. Of course the SLPs/SLTs who have devoted their careers to early intervention will claim that it works. But this claim in itself proves nothing.

Anonymous said...

"And controlling stuttering will mostly involved changing the cognitive behavioural aspects rather than the neuro."

This is where we part ways. There is ZERO evidence that cognitive behavioural approaches to stuttering result in an improvement in "controlling stuttering". Simply not the case. I'll say more when I get time, but just wanted to first underline this important point. It's a continuation of the old myth (and snake-oil approach) that's employed lots of speech therapists over the past 80 years or so.

Leys Geddes said...

You are a good guy, Adrian, and I'm very grateful for your support on many issues; but I don't think that anything I say will change your views on Early Intervention! I wish you could come over here and talk to some of our leading SLTs, and actually see what they are doing.

Norbert @ BSA said...

Anon

The Australians have worked on anxiety reduction through CBT and have found that while it is effective on reducing anxiety it has no impact on increasing fluency.

As ever in these discussions, there's a lot of pet theories without substantive evidence (such as "And controlling stuttering will mostly involved changing the cognitive behavioural aspects rather than the neuro. ") and a dismissal of evidence that doesn't fit into one's own picture.

Having read the BSA report, Adrian, could you outline which bit in particular you didn't find convincing?