On the relationship between autism and evolution

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It might be helpful to remember that the point of my original post was not that "deviance = bad" in any intrinsic sense, but that natural selection rewards (and predisposes us toward) normality.

Again we have fuzziness in terminology. Most often the word deviance carries a negative connotation. But in a strictly objective sense, deviance only means variation from some norm. I can't keep up with the context switching.

The problem is that, again, autism is a heterogeneous condition, and even though some autistic brains are "highly interconnected", any given autistic brain is just a likely (probably more likely) to be "underconnected".

What makes you think that autism is a hetergeneous condition? There very possibly could be one common cause to all the symptoms described under the current ASD umbrella - then again it may be that all those things that have been put under that umbrella are really a multitude of different conditions with different causalities.

There is no context switching here. Natural selection produces in species a general predisposition towards the norm for that species. The purpose of my initial post to this thread was to simply tease out some of the implications of that fact and apply it to the concept of autism. You're the one that's got me scurrying around, trying to explain why "deviance" is "bad". Don't ask me, ask natural selection!

I think that current research being conducted by the Markram's and others are narrowing down the root cause to something far more specific than "significant brain abnormality" You are right, there are a bazillion ways your brain can be abnormal. So far the Intense World Theory is doing a good job of explaining the common traits of autism and linking them all to increased interconnectedness in the brain not decreased connectedness. It is a promising theory - much work still to be done but based on what they know so far, people exhibiting autistic traits are more likely to have increased connections between parts of their brains that are not connected in NTs.

I don't doubt that this "increased interconnectedness" is a good way to describe some cases of autism. But the opposite trait, "underconnectivity", is widely recognized as the basis for autism in many cases, and has been for some time:

http://scholar.google.com/scholar?hl=en ... a=N&tab=ws

If both "increased interconnectedness" AND "underconnectivity" can both result in autism, what does that tell you?

Probably should record these things, but I recently read a paper that suggested localized overconnectivity and underconnectivity between regions

Sure, that could account for autism in some cases, too.

As could severely underdeveloped frontal lobes.

As could a lesion on the surface of the right hemisphere.

If every lesion causes autism then why bother with any other DX? Seems like you are over generalizing.

It might be helpful to remember that the point of my original post was not that "deviance = bad" in any intrinsic sense, but that natural selection rewards (and predisposes us toward) normality.

Probably should record these things, but I recently read a paper that suggested localized overconnectivity and underconnectivity between regions

A few relevant searches:

"Autism is not a single condition"--1,200 results
http://www.google.com/search?hl=en&safe ... =&aql=&oq=

"Autism is a single condition"--6 results, each of which is actually someone asserting the opposite
http://www.google.com/search?hl=en&safe ... =&aql=&oq=

John Elder Robison said...

Good afternoon Jonathan,

Some of you may follow the research I'm involved with at Harvard Medical School and Beth Israel Hospital. What I have learned is that there do seem to be brain differences that separate people on the autism spectrum from neurotypical folks. So science is beginning to figure out hard measurements that identify us as a specific subgroup of humanity, just as we have people with type a or type o blood.

You asked me about Lindsay Oberman the other day . . . this plasticity difference is her particular area of study.

However, there are no hard measurements (yet) that are predictive of autistic disability. The brain differences we see in autism apply equally to a nonverbal person and someone else you might call a brilliant fellow with a touch of Asperger's.

So the science is showing us (you, me, anyone else with this autistic difference) to be the same in that way, and the same in our differences even thouch some of us are profoundly disabled by this condition and a few of us are equally enabled.

No one has identified any repeatable reliable diagnostic criteria that would separate autism and Asperger's in adults. There are "high" and "low" functioning autistic and Aspergian individuals. While it's true that more high function people are identified as Asperger's, there is no hard line or diagnostic difference. It's really pretty arbitrary, it turns out.

That's the essential reason people advocate for this change. The available scientific evidence shows you and me to have many measurable brain similarities despite widely varying differences in social functioning and even general health.

Against that, you have a large number of people whose identity is wrapped up in a diagnosis, and you have concerns that publich health or education funding may be cut when and if a person's diagnostic categorization changes. Finally, you have the possiblity of diagnostic confusion and confusion by lay people because the range of affect in autism spectrum disorders is so broad.

Frankly, I don't know if I should be for or against the change, but it's not for me to decide, and I can live perfectly happily either way. Remember that we are in tne end all individuals and all fellow humans, two points that transcend diagnosis.

It really troubles me that people at different ends of the spectrum often have such fixed and opposite views. Speaking for myself, my exposure to folks like you (Jonathan) has broadened my views and (I hope) made me a better advocate for us all.

I surely understand why you would wish to remediate the components of your disability, just as I understand Carley's desire to be left alone. It makes me sad that there is not more mutual acceptance of these positions because if we banded together even knowing we had opposite therapeutic goals, we could do a heck of a lot more.

I do hope you talk to Lindsay and I'll be sure to come welcome you if you decide to visit us at the TMS lab in Boston.