Wednesday, July 23, 2008

Kate Watkins at Paris Workshop

With some delay, I am finishing off my comments to the Paris Workshop. If you are interested in the abstracts, you can find them on this very stylish French blog but translated into French: here. I didn't publish the abstracts by request from the organisers.

Kate Watkins is a lecturer at the University of Oxford, and a very dilligent experimentalist in brain imaging of the stuttering brain. Her recent work involved scanning young people who stutter and scanning stutterers while exposed to Altered Auditory Feedback (AAF).

She started out with a review of a few theories (basal ganglia, efference copy, incomplete cerebral dominance), and referred to the meta-analysis by Brown et al. (2005). She focused on the reduced white matter integrity found by Sommer et al, Chang et al, and Watkins et al, which indicates that the region is not well connected to other regions, especially between motor and auditory cortices. Interestingly, she superimposed the locations found by the three groups, and showed that they are quite close to each other; the Chang et al's location being being the other two. She also said that we need to look for bilateral abnormalities to find causal effects. Some were skeptical. She did not elaborate in depth so it is hard for me to judge. Maybe if one side is abnormal, the other side takes over and this shows in an abnormality, too. I think she mentioned animal experiments where one side was injured and the other side compensated.

Then she talked about her current work on scanning stutterers and controls while using AAF. They found the auditory cortex less active than in controls. She offered the interpretation of reduced input from the motor regions as the cause. And again they found white matter abnormality. I didn't follow it all in detail. But I think the essence was that under AAF there was less decoupling of the motor and auditory regions in stutterers, namely activity in motor region was more correlated to activation in auditory region. Moreover, I think she speculated that a big deficit might give a better compensation than a small difference. I am looking forward to reading the published research.

3 comments:

Olivier said...

The French link Parole de Bègues is very good, but don't forget i'm translating in french some of your own messages too on my blog.
Sorry, I feel forsaked. Sniff !

Tom Weidig said...

I know! I was only referring to the abstracts. You don't have them on your site, do you?

Olivier said...

No, I don't, you're right. I just translated your posts.