Friday, July 25, 2008

Reflection on autism diagnosis

Brain physiology is a tricky thing. One may dissect the brain of a cadaver, but observation of actual brain physiology during development is mostly limited to what neurophysiologists can see with electrical activity and MRI/CT scanning technology.

I was reading an article on autism diagnosis when it occurred to me that what is known about the brain are the areas where we should see electrical activity corresponding to various stimuli. Shouldn't children with autism display fairly consistent EEG data? The obvious problem--at least to parents of children with autism--is that getting the child to sit still for an EEG will be a major challenge.

If it is possible to determine which areas of the brain are or aren't firing the way they do in a neurotypical child, shouldn't stimulation of those areas with very low grade electrical shock or through specific physical activities help with the child's issues, at least early on, when the brain is most malleable?

According to Dr. Stanley I. Greenspan, therapy for autism works best when tailored to the individual child--but that's true, in my opinion, of neurotypical children and education, as well. I think that my friend Angie is correct in saying that the reason there is an autism spectrum and the reason it is so broad is that children with autism span the same range neurotypical children do--except with autism added. If that assumption is true, and it seems logical that it is, then there should be some common physiological feature that defines autism--which means medical diagnosis is possible, with treatment that has much less trial and error involved.

Has anyone seen research in this regard?


Anonymous said...

The analogy that I haven't seen made, but that I think of, is with stroke. There is a huge range of severity of effects, depending on the size location, and duration the blood flow restriction existed. The amount of recovery that's possible depends on this, as well as other instrinic features, neurological and otherwise, of the person with the stroke. And luck.

FI said...

Sorry, had to run and do something, left above post incomplete. Seizure activity (which I think is seen in about 20% in kids with autism) is much more common than the general populations. EEG's are good at detecting this. EEG's are commonly done on kids on the spectrum, without they're being one true autistic signature seen. There's a lot of data generated by a brain's electrical activity, and the EEG is an observed summation of many neurons firing, not a pinpoint exact schematic of all activity. It may be that the signature exists, but we don't know how to recognize the pattern. And with both epilepsy and stroke, the location of the activity varies widely. The location may vary in whatever's going on in autism too. Scientists on the question is epilepsy just occurring in the same kids, or is the epilepsy causing the autism, or vice versa, at this point, conclusively say "I dunno".
My daughter had a 24 hour EEG, and it was pretty miserable. They said they saw some atypical waves. Ultimately didn't drive treatment, but if they'd seen a lot of abnormalities, then the doc would have said an anti-eliptical may prevent "absent seizures", which was a possible explanation for her staring off into space and ignoring the world. A more sophisticated EEG may eventually be used to diagnose, and people who use EEG as the basis for biofeedback use it now as the template for treatment: