Theories of autism: lessons from Dr House

First published in Cracking the Enigma, 3rd March 2011

I’ve just been watching House. I say watching. To be honest, the details of this week’s plot passed me by as I was trying to follow it whilst simultaneously eating my dinner and having a conversation-slash-argument about, of all things, carbon taxing.

Anyway, the plot is pretty much the same each week: Patient shows up in the hospital with a weird combination of symptoms; House and team conduct various ethically dubious tests; initial diagnosis is  disconfirmed, usually by some new symptom; House finally ends up with the correct diagnosis and a single cause that neatly explains all of the symptoms. The patient this week had some extremely rare syndrome that gave her photographic memory and kidney failure.

So here’s the question I found myself asking: What lessons does House’s anarchic approach to medicine have for autism research? I’m not talking of course about his dodgy ethics, the lack of informed consent or the disregard for proper procedures. We’ve had enough of that recently thank you very much.

The crucial point is that for House the cause he ultimately identifies has to explain everything.

In case you missed Autism 101, autism is defined in terms of impaired social and communication skills, co-occurring with repetitive behaviours and/or restricted interests. But it’s oh so much more than that. Associated features include intellectual disability, epilepsy, sensory hypersensitivity, motor coordination problems, memory difficulties, face processing impairment. And so on. Autism is also associated with certain strengths, particularly in perceptual processing, and a disproportionate (but still rare) incidence of savant skills including amazing feats of artistry, musicianship, and calculation.

If House could explain autism, it would be the best episode ever.

The genius behind House (and yes I do realise he’s a fictional character) is the premise that, although there are many potential explanations for a given individual symptom, start looking at combinations of symptoms and suddenly the plausible underlying causes are reduced drastically.

I do wonder whether autism researchers may be missing a trick here. Social difficulties on their own could have multiple causes. But social difficulties combined with motor discoordination and epilepsy? Suddenly the possibilities are no longer endless.

But here comes the big “however”. House is dealing with a single patient. He knows that all of the symptoms he’s trying to account for affect that one patient. With autism, on the other hand, we’re dealing with a group of people who, in a very general sense, have some things in common but, as individuals, are all different from one another.  We know, for example, that people with an autism diagnosis tend to have issues of social anxiety and also that many are hypersensitive to sound. But we don’t know if it’s the same individuals in both cases. So should we be thinking in terms of a common mechanism that could neatly account for both features, or would that be trying to explain the co-occurrence of two things that never actually co-occur?

Over the years, a number of grand unifying theories of autism have been proposed that try and link together different symptoms. But they are all theories of autism, assuming that autism is a single homogeneous entity.

I’m not suggesting that we need a completely new theory for every individual. But I do genuinely believe that if we’re ever going to make sense of autism, we need to recognise the fact that the ‘core’ symptoms that define autism can come about by a number of different means. Any given theory probably won’t apply to everyone.

The lesson from House is that looking at all the symptoms might help identify these different causal pathways.