Saturday 10 December 2016

"Are we expecting too much from the extreme male brain theory of autism?"

The title of this post reflects the commentary published by Andrew Whitehouse [1] (open-access) discussing the meaning of the findings reported by Kung and colleagues [2] who quite categorically stated that there was: "No relationship between prenatal androgen exposure and autistic traits" in their study.

OK, androgen exposure and psychology basically refers to the extreme male brain theory and autism which suggests that the so-called over-representation of autism in males is potentially down to hormone exposure (testosterone). The theory implies that androgen exposure at critical points in early development are skewing brain development towards a more 'male brain'. The definition of a male brain: well, apparently men are better systemisers than empathisers (better engineers that priests, I assume). The extreme male brain (EMB) hypothesis is an extension of the 'Theory of Mind' (ToM) stuff, which quite a few years back suggested that those diagnosed as being on the autism spectrum have greater difficulties in decoding mental states such as intents and desires. Grand psychological theories at their very finest you might say.

The problem is that whilst ToM and the EMB theory made great psychological textbook reading (certainly in their heyday between the mid-1980s up to the late 1990s) and have spawned a whole industry around testing and teaching ToM for example, the scientific evidence for these concepts being exclusively and universally attributable to the great heterogeneity that is autism is not actually all that great. A shocker I know; and don't even ask about how comorbidity around autism might also be pretty important to such psychological concepts (see here and see here for example).

Whitehouse - who himself has done some research in this area - talks quite a bit about the hows and whys of quite a few negative findings when it comes to the EMB theory (yes, there are quite a few) and what perhaps needs to be done to "advance beyond this stalemate" in relation to the EMB theory and autism.  His suggestion: "future research must first understand how the prenatal hormone environment relates to individual behavioural dimensions, and then incorporate this knowledge into the investigation of links with the more aetiologically and phenotypically complex profile of ASD [autism spectrum disorder]."

These are wise words indeed but I'd suggest this perhaps applies to any 'theory' in relation to autism, psychological, biological or genetic. Indeed, I believe that other authors (see here) have already staked their claim on how using the word 'autism' as a starting point for anything other than a descriptive label probably isn't going to move autism research along any time soon; autisms people, autisms. The challenge is also one of moving away from generalisations; so talking about male and female brains is probably about as useful as talking about left and right-sided brains. Indeed, I'll refer you to some discussions about 'gender brains' between the main proponent of the EMB theory and a psychologist a few years back (see here and see here) that kicked up some scientific dust.

I personally do think there is something in the findings looking at androgen levels and cognitive styles in the same way that there is something in most (replicated) peer-reviewed research when it comes to autism. But as Prof. Whitehouse indicates, it's probably going to be more relevant to some on the autism spectrum than others, and even then, disentangling the 'cognitive' structure of autism is going to be important [3]. The days of grand over-arching psychological theories about autism do seem to be riding off into the scientific sunset as the huge diversity and 'burden' of over-represented comorbidity start to come into plain sight. And certainly I don't think it's too rude to end with the words 'about time too'.

To close, I hark back to simpler days or should that be to a simpler future when Buck Rogers showed the 25th Century how to boogie. Tell him what you think Twiki.


[1] Whitehouse AJO. Commentary: Are we expecting too much from the extreme male brain theory of autism? A reflection on Kung et al. (2016). J Child Psychol Psychiatry. 2016 Dec;57(12):1463-1464.

[2] Kung KT. et al. No relationship between prenatal androgen exposure and autistic traits: convergent evidence from studies of children with congenital adrenal hyperplasia and of amniotic testosterone concentrations in typically developing children. J Child Psychol Psychiatry. 2016 Dec;57(12):1455-1462.

[3] Happé F. et al. Time to give up on a single explanation for autism. Nat Neurosci. 2006 Oct;9(10):1218-20.

---------- Whitehouse AJ (2016). Commentary: Are we expecting too much from the extreme male brain theory of autism? A reflection on Kung et al. (2016). Journal of child psychology and psychiatry, and allied disciplines, 57 (12), 1463-1464 PMID: 27859346

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