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I often hear other neurodiversity advocates refer to autism as a different "brain wiring." This is a rather unclear term, and I am not fully sure where it originally came from. But I take it the point is that we have something different about our neurology that makes us autistic—some kind of essential difference that provides the basis of and legitimization for our autistic identity.
In turn, this claim is often accompanied by the further notion that "autism is genetic," a claim which is often justified with a link to some newspaper article or another that reports how a new study has "shown" or "found" that autism really is genetic after all.
There is something obviously right in these claims, but they can also be highly misleading, especially when taken together. It is true that autistic people often share various cognitive tendencies that seem to have a strong hereditary basis. But if we understand the claim to be that all autistic people share a genetically-based neurological essence, this framing encounters two highly significant issues.
The first is a scientific problem—namely, that such biological essentialism is not supported by the evidence. In fact, there is no known biological basis that is clearly definitive of autism at all. True, some studies have indicated certain tendencies in neurological functioning or structure, but often these findings are based on very small samples and are not reproduced; and in fact, each autistic brain is unique, rather than being the same as other autistic brains.
The same problems emerge with so-called autistic "risk" genes. Over 1,000 have been identified, and they rarely come in the same combinations or through the same epigenetic processes, making it very hard to claim that there is anything like a shared genetic basis for autism. Moreover, as Keller and Miller have noted:
"...finding positive heritability for a mental disorder does not vindicate the mental disorder as a diagnostic category. To a first approximation, every reliably measured behavioral trait shows positive heritability—even constructs such as television viewing and political attitudes. Any arbitrary 'disorder' composed of unrelated but heritable symptoms will show credible heritability. "
The upshot: Although there are very general population tendencies when it comes to autism, there is nothing like an essential, defining neurological or genetic marker shared by all autistic people as individuals. So the claim that any two autistic people share the same "wiring" as each other, unless they have somehow gone to a lab and been tested to verify this, is unsupported by science. Equally unsupported, then, is the (often implicit) notion that shared wiring is what grounds our shared identity or political voice (I'll return to this below).
The second problem is more political and ethical. This regards how biologizing and essentializing categories such as autism tend to reinforce social processes that are at odds with the emancipatory aims of the neurodiversity movement. As the authors of a 2011 review article on the biologization of human kinds summarised, evidence consistently shows that:
"People’s understanding of genetics with relation to life outcomes is shaped by their psychological essentialist biases—a process termed genetic essentialism—and this leads to particular consequences when people consider the relations between genes and human outcomes... genetic essentialist biases have played in eugenic ideologies and policies, and... these biases shape and are in turn shaped by contemporary discussions of genetic research."
Biologizing and essentializing human kinds (whether race, gender, or disability) in popular discourse ultimately function both to support a thing like eugenics and to increase stigma. And these, of course, are precisely the kinds of things that the neurodiversity movement has emerged to resist.
I certainly do not conclude from this that the neurodiversity movement is inherently flawed. But I do believe that certain proponents need to be more careful about the biological reductionism that they have too often uncritically adopted from biological psychiatry. Here, we need to follow those such as autistic sociologist Damian Milton, who has long resisted such temptations.
For Milton, the notion that autism is "scientifically valid as a natural kind" is untenable, and we are "unlikely ever to find… a simplistic explanation of what autism ‘is’ at a biological level."
The alternative view holds the classification of autism as a human construct that emerged within certain power dynamics and a specific social and historical context, rather than being a natural grouping that we simply discovered.
In this view, autistic people can have a shared voice, and shared interests, but these are not based on some kind of shared biological essence. Rather, they are based on our similar social positioning, our emerging culture, and our irreducibly complex manifold of psychosocial similarities, in what we might call our shared autistic form of life.
There is a historical cause for hope here, too: All the previous major civil rights movements (regarding race, gender, sexuality, and so forth) managed to overcome not just the pathologization of whichever group they were concerned with, but also essentialism and biological reductionism.
This took some time, and much debate, in each case. But just as (most) feminists have come to reject the notion that there is a biological essence of any given gender, so too can more neurodiversity proponents come to reject biological reductionism and essentialism when it comes to neurominorities. Or at least, this is what will need to happen for the emancipatory aims of neurodiversity proponents to become fully realized.
