Sunday, October 28, 2007

Partial Agenesis of the Corpus Callosum

I learned something interesting about myself recently. Because of some pretty severe migraine headaches I was having I decided to get an MRI scan of my brain. Imagine my surprise when I found out I have a small corpus callosum!

Here's an image of it:

Click to enlarge
And here's a "normal" one, for comparison:

Click to Enlarge
Naturally, I was curious about the implications. What has this meant to me, if anything, in terms of, e.g., my personality, my perceptions of the world, and my intellectual development? Sadly, there's not a lot of info out there to help me answer such questions.

Wikipedia's relevant entry concerns only the corpus callosum's complete agenesis, which is associated with some pretty severe developmental deficits - none of which, thankfully, apply in my case. It does, however, mention Autism. This caught my eye because I recently had an ex-girlfriend accuse me (gently) of having Asperger's Syndrome, which is an autism spectrum condition. Perhaps she's right. I'll admit to a certain level of shyness, dislike of parties, and inability to pick up on subtle non-verbal cues, but I'm not in a position to reliably self-diagnose whether I could be considered more than, say, 2 standard deviations from the mean in that regard.

Meanwhile, PubMed is a little more helpful on the subject, though not much. Again, I get the sense, from reading those abstracts and articles, that I should be a lot worse off than I am. Even the National Organization for Disorders of the Corpus Callosum is unhelpful. This all leads me to wonder: just how unusual is my condition? How strange is it for someone with it to go 38 years showing no real signs of it? MRIs of the brain are expensive ($2K a pop, without health insurance), so not many people get them. Maybe there are hundreds of thousands, or even millions, of outwardly normal - if a bit shy - people out there who have no posterior corpus callosi.

I've contacted some folks at Cal Tech who are doing research on this. Hopefully they'll have a few answers, but it seems likely that nobody really knows much of anything at this point.