Tuesday, February 26, 2008

Research from Iran

I am happy to see that there are also Iranian researchers working on stuttering. As with the Chinese, I have always been impressed by the Iranians I have met. They were highly educated and very civilized. The Iranian news agency talks about research on a computer model to simulate human speech processes and thereby showing that basal ganglia malfunction could be at the core of stuttering: see here. I am impressed by how scientific and clear thinking the article is, unlike 90% of articles from Western authors. If anyone knows who the researcher is, please let me know! Here is a shortcut of the press release.

Iranian researcher in medical engineering has worked out a project examining impacts of medical treatment on patients suffering from expression difficulty, stuttering. He managed to design a computer model upon the brain function to monitor the impacts of the medical treatment.
The mechanisms behind the stuttering are still not clear and scientists have introduced variety of reasons for it but a major line of research over at least three decades has investigated the possibility of a speech motor control disorder as at least one component that this is influenced by emotional stats and environmental factors.
There are strong indications that the basal ganglia-thalamo cortical motor circuit, through the putamen to the supplementary motor area, plays an important role in the pathophysiology of stuttering. Also the influence of emotional states on stuttering is well compatible with the suggestion of stuttering as a basal ganglia disorder.
Hence, the core dysfunction in stuttering is the impaired ability of the basal ganglia to produce timing signals because of the unregulated value of dopamine receptor density in it.
Although scientists showed the relation between the basal gang and stuttering, but yet there is not appropriate computational model to show this relation quantitatively. In this study, we propose a computational model that explains the role of basal ganglia in stuttering.
Different parts of the brain involved in stuttering are all considered in our model. Our computational model has considered the involved parts of the brain in a fairly accurate way, explaining the behavior and mechanism of the disorder according to physiological information.
Using this model, we can predict the effect of changes in dopamine and other basal ganglia neurotransmitters in different situation such as emotional states.
Also, we can predict the effects of different drugs on the stutterers.


Richard H. said...

The Iran research fits right into the "excessive dopaminergic activity" theory of stuttering advanced my Dr. Gerald Maguire and others (including me: http://members.aol.com/rharkn/).
There are several pages on the brain basis of stuttering there. I've also elucidated step-by-step the pathway from the brain's striatum (caudate/putamen) to the motor cortex, showing how GABA-receptor stimulation ultimately decreases dopaminergic activity and thus decreases motor cortex excitation. This is how Pagoclone, the selective GABA-agonist "anti-stuttering" drug wending its way through the FDA approval process, works. Excessive dopaminergic activity increases what I've termed "excitation feedback," which is discussed in detail on the above-mentioned Web site. I plan to post more about this on the site soon.

Best regards, Richard H.

ig88sir said...

This is not true for all PWS. I have tried both Zyprexa Zydis and Pagaclone with no fluency gains and severe side effects (Zyprexa). Even if dopamine antagonist medication helps some, the basal ganglia excitation is not the sole culprit. Don't forget the left hemisphere white matter density deficit and right hemisphere compensation (in low stress situations of cooouuurse).

Anonymous said...

and of course, no response to your comment. surprise.