Autism, temporal binding... and chiropractic


"There you go sir, that should sort out your social interaction difficulties"

I'm famous. Well, sort of. Earlier this week, one of my colleagues sent me a link to a YouTube video in which chiropractic doctor David Sullivan discusses one of my papers on autism and how it influences his "evidence based practice". 

It's a classic of its genre. The video starts off with a spinning brain and funky science-o-mercial music. And Sullivan somehow manages to equate autism with a dodgy dial-up internet connection whilst weaving our  hypothesis in with Einstein and the space-time continuum. I'm flattered, but also more than a little baffled.



Our paper was called "The temporal binding deficit hypothesis of autism" and came out in the journal Development and Psychopathology nine years ago (now there's a scary thought). In it we suggested that autism might be caused, at least in part, by a reduced interaction between different brain regions. Based on the idea that communication within the brain involves synchronization (or 'temporal binding') of oscillatory neural activity, we predicted that there would be reduced synchronization of brain oscillations in autism.

I'm always pleased when people read and share my papers, especially when they greet it with this degree of enthusiasm. Sullivan gets a lot of things wrong but, as someone who likewise blogs on papers I find interesting but maybe don't completely understand, I can't be too critical [1].

But there are a number of things that it's important to clarify.

First and most importantly, our paper does not endorse chiropractic as a treatment for autism. We don't even mention it. To be fair,  Sullivan doesn't say that we do, but if you were distracted by the spinning brain, the white coat, and the fancy neuro-terminology then you might come away with that impression.

Second, while I'm prepared to admit that I know very little about chiropractic, I really can't see how people with autism might benefit from someone fiddling about with their spines. Last time I checked, autism wasn't considered to be a form of back problem. Sullivan doesn't provide any evidence that chiropractic is a suitable treatment. He doesn't explain how it might be beneficial, even in theory. More to the point, he doesn't elaborate on how the insights gained from our paper are at all relevant to his practice.

Digging around on his website, we do however get this mission statement:
"Therapeutically, the goal is to restore optimal synchronization and inter-communication between all brain areas. As this process evolves, the brain becomes more cohesive in its function, and the child is able to perform at a more age-appropriate and higher functional level."
But there still nothing as to how his chiropractic treatments would actually achieve this goal.

Third, our paper presented a hypothesis. We didn't show anything; there was no evidence, no data; we had an idea and ran with it. As it happens, there have since been a number of studies suggesting that autistic brains on the whole are less well-connected than your average brain. But, it's not nearly as simple or straightforward as we initially hypothesized. Different studies find that different neural pathways are disconnected. Some studies even suggest heightened connectivity. And while there's lots of evidence for abnormal brain oscillations, look more closely and the actual pattern of abnormality isn't very consistent. Another big problem is that evidence for abnormal brain connectivity has been found for umpteen other disorders that are quite different to autism. And there's a fairly compelling counter-argument that anomalous brain connections might be a consequence of autism rather than its cause.

As in so many other fields of autism research, progress is being made, but each new finding generates as many questions as it does answers. We're still a long way from understanding the neurobiological basis of autism in its various manifestations. Changes in brain connectivity and neural oscillations are, I believe, part of the story. But it's going to be a very complicated story.

Sullivan claims to have "a thorough understanding of the science and neurology behind ASD". If he does, he's in a minority of one.

Footnote:

[1] I do make a point of emailing the authors of the paper I'm blogging and giving them the opportunity to comment and make corrections. And if there's something I'm not sure about, I run it past them before posting.

Reference:

ResearchBlogging.orgBrock J, Brown CC, Boucher J, & Rippon G (2002). The temporal binding deficit hypothesis of autism. Development and psychopathology, 14 (2), 209-24 PMID: 12030688 Download PDF

Update 15/7/11:

Kylie Gray (Monash Uni) has passed me a chapter on autism that she wrote for a chiropractic textbook with a view to educating chiropractic students about autism. She did a comprehensive literature search and found no evidence of efficacy.

Here are the relevant paragraphs:
"There is no evidence [the editor added the words "at this point"] of the efficacy of chiropractic in the treatment of autism. A few cases studies, not published in peer reviewed journals, have claimed that successful outcomes were achieved through the use of chiropractic with children with autism (Gleberzon 2006). Case reports and anecdotal reports do not provide evidence for the efficacy of a treatment; randomized clinical trials are needed to investigate the effects of any treatment.

"It has been noted that primary management of the treatment of a child with autism by a chiropractor is neither in keeping with knowledge of current best practice nor in the best interests of the child (Ferrance 2003, Gleberzon 2006). It is essential that professionals working with the families of children with autism are knowledgeable about the demonstrated efficacy, or lack thereof, of treatments that are available. It is important for professionals to be able to explain these issues to families and provide them with informed advice about their treatment options."
Gray, K.M., Brereton, A.V., & Tonge, B.J. (in press) Autism. In N Davies (Ed.) Chiropractic Paediatrics. Edinburgh: Harcourt Brace & Company.

Update 20/08/11:

A number of commenters have pointed out that Dr (of Chiropractic) Sullivan is employing "Brain Balance" techniques which may or not involve chiropractic treatment of autistic kids after all. I've contacted him to find out but haven't had a response. Anyway, if you've come across Brain Balance and think that it sounds vaguely plausible, I'd urge you to read this and this on the Science Based Medicine website.


Further reading: