Saturday, May 17, 2008

Newsflash from Paris conference


I just made my way back to Luxembourg from the one-day conference in Paris. Have you ever been confused of the difference between "efficiency" and "efficacy"? Here is a good example: I took the TGV, the world's fastest train (the most efficient in terms of speed), but completely ineffective (i.e. in terms of actual output), because my return journey took 5 hours instead of the 3.5 hours with the old trains or the 2 hours in the morning!!! Some troubles on the rails which caused a late departure and reduced speed limits!

Here are my talking points:

1) We are currently seeing second generation brain imaging studies. I am very impressed with the latest very cool brain graphics, better scanners and the latest signal manipulation, interpretation (e.g. fiber tracking) and statistical software. The latest studies are now much more reliable than the first generation. I would even go as far as to say that we should forget about all studies older than 2-3 years, except maybe keep a summary in our minds with the meta-analysis by Brown et al.

2) All groups (Chang et al, Watkins et al, and Kell/Neumann et al.) have confirmed the presence of a white matter defficiency in the left frontal cortex, first found by Sommer et al. with more primitive and low resolution DTI scanning. What they disagree on is the exact location, however there are most likely differences in the sample and methods.

3) There was an interesting observation that stuttering and other disorders often show (similar) abnormalities, but that these abnormalities do not necessarily translate to dysfunction. A fascinating interpretation could be that a brain loaded with abnormalities actually shows a decreased (global) brain plasticity to compensate for a defficieny. And the people with disorders are just the biased sample of people who have failed to compensate adequately.

4) Riitta Salmelin talked about MEG and told us that she is going to take a second look at stuttering, after her first MEG study on stuttering where she showed some reversal in activation for people who stutter. MEG shows electrical activity down to a 1ms resolution, and she now has a working method to determine the time sequence of events. I am very keen to see what she will find as this tool has never been applied to stuttering!

5) No theoretical breakthroughs at all. The consensus seems to be to wait and get more empirical observations from the second generation brain imaging, especially in terms of correlating activities between different regions first.

OK. That's my first twist to a very interesting conference. I'll talk about each presenter over the next weeks. And pictures!!

6 comments:

Anonymous said...

Very interesting. I am a stutterer who recently self diagnosed as Asperger Syndrome, which is another Persistent developmental disorder. It fascinates me that both stuttering and Aspergers are found in about 4 times as many males as females, and I'm wondering if they may be rooted in in the same issues in the brain.

Alan Falck said...

Hi Tom, any updates on brain activity while under AAF ?
Alan

Tom Weidig said...

Yes, Kate Watkins was presenting resuls from her AAF brain imaging experiments. She also showed that two brain regions were anti-correlated, but only in people who stutter without AAF, but not in fluent people or people who stutter with AAF.

I cannot remember any details. You would need to contact her for more details. She is a lecturer at Oxford University. I guess if you are going to Oxford, you will meet her.

Best wishes,
Tom

Anonymous said...

I think some experts now say (based on newer research studies) that the real ratio may be 2 males to 1 female. Or even 1 male to 1 female. But a lot more females spontaneously recover (with no help or therapy). So the adult ratio is 4 to 1.

I don't know about Asperger's...

ac said...

Can't wait for the summaries of the rest of the talks.

Sounds like new results are a few years off, if the current focus is on generating new brain imaging datasets.

AspergerStutter said...

I notice this blog post shows up high in the google results for "asperger stuttering", so I hope you don't mind my noting that I've created a new yahoogroup for people who are interested in both conditions:

http://health.groups.yahoo.com/group/AspergerStutter/

Please join if you are interested in Stuttering and Aspergers.