Thursday, May 22, 2008

Soo-Eun Chang's talk at Paris

Sou-Eun Chang spoke second at the Paris conference. Soo-Eun is a post-doc and a trained speech and language pathologist. She was there together with her boss Christy Ludlow. They are based at Bethesda, close to Washington, at the National Institute of Health (NIH), a US government institution. I visited them at NIH in October at the same time as I visited a friend of mine who heads a brain imaging lab studying the visual cortex and with whom I often have discussions on neuroscience, genetics, consciousness, meaning of life (not very uplifting really :-), and politics. NIH is a bit of scary place: lots of security checks, the usual government big-brother-is-watching regulations with email and chat monitoring and the feel of a science factory with scientists as hens studying hens in their labs! But they have superb facilities, good scientists and the researchers are generally not dependent on outside money and hassled with writing millions of research proposals. It was Soo-Eun's first time in Paris, and she was probably a bit on a culture shock! Unfortunately, as NIH policy generally forbids their scientists to stay on after a conference, they had to go back the next day! What a shame! Check out their group's webpage for more references on their work: here.

Soo-Eun talked about her brain imaging work on older children, which we have already discussed on this blog. So let me first refer you to these posts: here, and here. She spent a rather long time on established stuff like the Ambrose and Yairi study on childhood stuttering and recovery (the group helped them with their study), on past brain imaging studies, and on how the latest brain imaging works (with very cool pictures and process diagrams), which was well presented but gave her less time to talk about her work and ideas. I always prefer to hear less in more depth from own work and repeated several times in different ways! This is especially true for all the brain imaging work, where people throw in all kinds of brain regions from different methods, one every 30 seconds, and I just get confused and have no time to digest. Too many details, especially because the terms are not second nature to me. But I cannot imagine that the speech therapists present actually understood what was said, and that the professional neuroscientists remember it all.

Soo-Eun's philosophy seem to be roughly: Stutterer's brains react to stuttering, and it therefore makes sense to look at younger brains to reduce the effect of brain plasticity. Not only compare with controls, but also compare the group of recovered and persistent early teens. Expect that even recovered teens show abnormalities, because strokes in recovered adult stutterers often make stuttering re-appear, and because the brain is well able to compensate for a deficiency to restore function if not normal structure. They choose 22 boys from the age of 8 to 12. Interestingly, she said that they choose to exclude nearly 50% due to other issues like ADHD. This is an important piece of information. I should have asked why they did not just scan them, and then analyse separatedly. As far as I followed, the two major results are: 1) Replication of white matter difference in a major fibre tract similar to what Watkins et al. and other studies found. Appararently, it is a major fiber tract supporting auditory and motor integration. 2) No replication of some gray matter differences from adult scanning results. (Remember: white matter are the neurons' tentacles connecting between neurons, and gray matter are the neurons themselves.) She also talked about the difference between recovered and persistent kids, but went too fast for me to digest or write down details. But recovered kids always seemed to be different to controls and persistent kids. So we should really be more precise when using the word recovery. We need to distinguish between functional recovery and structural recovery. Recovered kids generally seem to be fluent (functionally recovered) but still not normal (structurally).

After the talk, Peter Howell noted that some kids from the age group 8-12 are actually recovering from stuttering, and they might distort the grouping of recovered and persistent kids. He said nearly 50%, which sounds very high to me. But it might be true, and is good news for the Lidcombe treatment trialers to get more results out of nothing! :-) However, I guess they control this effect by monitoring these kids and if recovery is happening to do a further group analysis.

1 comment:

Anonymous said...

From your previous post I looked up how Broca's area / Basil Ganglia relate to speech and attention. I think that there is a connection that makes sense and is not the result of a brain injury. If 50% of the kids were screened out secondary to ADD/ ADHD symptoms, could it be that the kind of ADD/ ADHD and anxiety symptoms documented might be an added "soft-sign" of the same structural areas related to stuttering stuttering.