Wednesday, April 7, 2010

Conference Report, Part 3: Eric Courchesne

The third and final installment from the Autism Society of Wisconsin conference is the Saturday afternoon keynote by Eric Courchesne, director of the UCSD Autism Center of Excellence. His talk was called "The Neural Origins of Autism: Evidence of Prenatal and Early Postnatal Brain Growth Abnormalities."

[Note - I'll be calling him by his first name, as I did with Paula Kluth and Temple Grandin, though in each case the more formal choice would be the title "Dr."]

In contrast to Temple Grandin's wide-ranging themes, Eric's presentation built a thesis. He started by referring to a 2009 report from the Information Centre of the UK’s National Health Service that found an ASD rate of 1 in 100 among adults in England, using modern diagnostic standards. This converges with the 1 in 110 rate for children in the US as published by the CDC this past December... in other words, he was taking the stance that the autism "epidemic" has much more to do with diagnostic changes than with a true rise in the condition. (The England study has been somewhat controversial, and Eric was careful to caution that it needs to be replicated before we can give it too much weight.) Come to think of it, Temple hinted at a similar position in her presentation: "Geeks and nerds have always been here... Who do you think made the first stone spear? It wasn't all the yakety-yaks around the campfire!"

Eric went on to point out that until recently, much of the brain-scan research in autism has been done with adults. But if you want brain research to illuminate the "why," you need to start much earlier, back to the age at which atuism first begins to be apparent. So he and his wife, fellow researcher Karen Pierce, have been working on brain studies with little tykes.

One set of results focuses on brain size. It's well-established that people with ASD have unusually large brain size. Courchesne et al (2003) looked children with autism or PDD-NOS and traced their head circumference (HC) records back to infancy. The findings: birth HC of the infants with ASD was smaller than the norm, but shot up to a mean at the 84th percentile by 6-14 months. The children with autism had a greater increase in HC than the ones with PDD-NOS. [This rings true for our Joy, by the way. Her head was at the 70th percentile shortly after birth, 95th percentile by six months, above the 97th by 9 months, and has never gone below that figure since. Rose had a sizable head too, 90th percentile at 12 months, but back to the 82nd percentile by 2 years of age.] Anyway, Eric listed 7 other studies in support of this finding, starting with Dementieva et al 2005.

The next work he described involved doing sleep-MRIs on one-year-olds. To get the right group of little ones to scan, Eric and Karen have set up a network of primary care physicians who do a screener at age 12 months to identify children who show early signs of ASD. Those identified as at-risk then become potential research participants. This network & screening impresses me as a two-in-one coup, by the way -- not only does it serve the research, but it gets the kids screened! I've learned via LEND that there is surprising hesitation in the pediatric community when it comes to implementing standardized developmental screening, whether for autism or just in general.

Anyway. Not only are these MRIs confirming large brain size in children with ASDs (particularly frontal & temporal lobes) but are also showing that autistic-tyke brains are responding differently to normal speech, with activation on the "wrong" side of the brain.

So where are these brain overgrowths coming from? Is it more brain-cells, or something else? Cadaver research on small children can be a hard thing to think about because there's always a tragedy underlying, but generous research donations by bereaved families has allowed some study that actually counts brain cells -- with the astonishing result that the brains of children with ASD had an average of 55% abnormal increase in the actual number of cells!

AND. Eric drove this home hard. Almost all brain cells are generated PRE-NATALLY, second & third trimester. The overgrowth in numbers of brain cells cannot be caused by vaccines.

So why don't symptoms show till later? He showed a fascinating slide illustrating human frontal cortex development. Even though newborns have all their brain cells, those cells are small and have few connections. But between the ages of 6 months and two years, the cells themselves grow and circuit formation goes wild. At that point, the difference in number of brain cells and how they connect begins to really matter.

Eric's lab is currently studying the layers of the cerebral cortex, a process that he expects will lead to identification of genes that are implicated in layering defects. He spoke of his hope that within 6 or 7 years, that the understanding of the brain-basis of autism will jump by leaps and bounds. As he made this prediction, he became choked with emotion... "I have tremendous hope," he said.

When Eric talks about the importance of brain-based autism studies, he also speaks very strongly about the massive waste of research dollars that have been poured into the generally-discredited vaccine causality hypothesis. This infuriates him. And it's not just a casual opinion with him. It's very personal. You see, as he climbed the steps to the stage, he had to support himself with his arms because his legs don't work quite right. He had polio when he was four years old, in the last epidemic wave before polio was essentially wiped out.

By vaccines.

He got a standing ovation at the end of his presentation.

Note: sorry that my referencing of particular papers fell off after the first bit of the presentation. I thought I took better notes than that, but apparently not. Please be assured, though, that every one of the findings was backed by peer-reviewed, published articles, and that Eric took great care to mention the extent to which his work has been replicated. Unlike, and he made this point very clearly, the work of a certain Andrew Wakefield, recently retracted by the Lancet.

Thus endeth my conference reporting. I hope you can see why it seemed important to me to share all three of these presentations! Thank you for hanging with me. I think that as LEND winds down, we'll be returning to our usual Joy-based programming here on Elvis Sightings.


Anonymous said...

Agreed, I can see why it was important to you to share - each presentation gave more meaning to my understanding of autism and the science of treatment.

You gave important humor and humanness of the speakers, too. (Speaking as a nerd who I can only hope has a spear maker in her genealogy.)

I have tremendous hope, too. Because of Eric.

Viktoria said...

I just wanted to tell you how much I enjoy reading your blog. I was referred to it by the lady who commented above! I'm not specialized in ASD, but in cerebral palsy and related motor disorders, yet this is such a refreshing read. ASD, if anything, attracts even more quackery and snake oil therapies than cerebral palsy do, and it's great to see that not everyone is hooked on those.

Elizabeth Channel said...

Wow! I would have liked to hear that fellow!

My child with an ASD diagnosis had an off-the-charts head percentile prenatally, and that has continued through his life. (His older brother was in the 95th percentile too. And my husband has an abnormally large head.) We even had an MRI when he was a toddler to eliminate a possible tumor or hydrocephalus because his head was so large and his fontanelle was not closing appropriately. (It eventually closed without problems.)

I wonder if there are any connections with the fontanelle issue and ASD. That would be interesting to research...

K- floortime lite mama said...

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