Brain Scans               

Sally Shaywitz, Pediatric Neuroscience, Yale University, Author of Overcoming Dyslexia. Source: COTC Interview - http://www.childrenofthecode.org/interviews/shaywitz.htm#WhatBrainScans

Limitations of Current Brain Scans

David Boulton: Do we have any brain imaging tests that you're aware of that allow us to see a signature distinction in the structure or processing of the brain before the process of learning to read that predicts difficulty in learning to read?

Dr. Sally Shaywitz: We don't. I know exactly what you're saying, and that would be just a really commendable goal. Currently, when we do functional brain imaging, children have to lie very still, and the youngest that I think we or others have done is about six-and-a-half. So then at that time that would be when children are about near the end of kindergarten. So you'd expect them to have the rudiments of early reading in place.

It may be possible, with other technologies that are evolving, to be able to identify children earlier.

David Boulton: So, currently there's a rather significantly sized uncertainty about that threshold.

Dr. Sally Shaywitz: That's right.

David Boulton: Okay. Relative to your tests, how fast a frequency variation can you see? I mean, for example, with Keith Rayner's work we're seeing that the difference between graphemic and phonological follow-up is happening in a five to twenty-five millisecond time window when somebody is reading well.

Dr. Sally Shaywitz: Well, Functional Magnetic Resonance Imagining doesn't give temporal information.

David Boulton: So, then difficulties associated with the time precarious interactive interplay between these various modules you're identifying can't be seen with the equipment and setups we've got yet.

Dr. Sally Shaywitz: Certainly not with the Functional MRI. But what we can see, for example, that when we present words to children very quickly if they are using the word formation area that's critical for fluent reading. That's possible.

Now there are new techniques that show how the parts of the brain are connected, so we can have a sense -- and that's what I was just telling you about in the last research I mentioned, where we looked at the persistently poor readers who seemed to have all the systems in place, but they weren't connected appropriately, they weren't connected properly. I think this is an area where the technology is evolving very, very rapidly, so I think things are really changing as we speak.

David Boulton: So, we're heading towards being able to peer into this space. It seems when children are reading, if we really track their facial expressions and articulations, there's a hesitancy, or starting and stopping that happens for struggling readers, and that that starting and stopping has a correspondence to a number of things. One thing for sure is the kind of ambiguity they're processing at that moment, yes?

Dr. Sally Shaywitz: Well, yes, I think each of us would represent that a little bit differently.

Sally Shaywitz, Pediatric Neuroscience, Yale University, Author of Overcoming Dyslexia. Source: COTC Interview - http://www.childrenofthecode.org/interviews/shaywitz.htm#LimitationsofCurrentBrain

Magnetic Imaging Methods     

Because we now have the advantage of technological imaging in non-invasive imaging in humans both through evoked potential electro-physiological methods and also through functional neuro-imaging methods. Both magnetic imaging methods have been able to show that, indeed, not only are the children behaviorally processing more quickly, their language and reading scores on standardized tests are improving. And the differences between their brains and the brains of children who are better readers are becoming less distinct over time. So, those areas that are more involved in certain aspects of the reading task, particularly the phonological aspects, which are distinctly different between a group of children who are struggling with reading and a group of children who are reading really well are diminishing.

Over time, if your methodologies of intervention are working, one should be able to determine that using not only behavioral methodologies works, but also physiological and neuro-imaging. That’s a real advance. This is brand new data.  For the first time we’re beginning to see studies in which one is able to actually evaluate the effectiveness of reading interventions or other types of interventions. Very similar kinds of approaches are being used with patients with stroke, both for the motor systems, the language systems, and the perceptual system and sensory systems. Particularly, we’ll see more and more studies coming out in which these neuro-imaging procedures are being used as assessments for the efficacy; first of all assessments for a deficit, and then used as an additional way of evaluating efficacy of one method over another. It’s a new world. 

Paula Tallal. Board of Governor's Chair of Neuroscience and Co-Director of the Center for Molecular and Behavioral Neuroscience at Rutgers University. Source: COTC Interview - http://www.childrenofthecode.org/interviews/tallal.htm#ExercisesToSpeedUpDistinctionProces

Newer Technologies Image the Brain in Real Time

The reality is that if you look at these newer technologies that are able to image the brain in real time - not just take a picture of what lit up and subtract it out from everything else, but really follow using full head evoked potential or magnetoencephalography or something that can actually follow the response - in general, a lot of the brain is working to process information as complex as speech. And when you get into reading where you’ve got the language plus the written part to be decoded and reassembled and comprehended, we are really using a lot of parts of our brain.

Paula Tallal. Board of Governor's Chair of Neuroscience and Co-Director of the Center for Molecular and Behavioral Neuroscience at Rutgers University. Source: COTC Interview - http://www.childrenofthecode.org/interviews/tallal.htm#AmbiguityProcessingTakesTime