There are physical findings which seem to be more common in autistic people, and which, if found, might aid in diagnosis. But they can't just brain-scan someone and say "This one's autistic and this one isn't." In fact some studies have found the same brain abnormalities in non-autistic relatives of autistic people, as in autistic people.
It's sort of like, if studies found that lots of women owned poodles, it would not necessarily mean that everyone who owned a poodle was a woman, or that every woman owned a poodle. So even if that were true, they couldn't just check out who owned poodles in order to figure out who was female, nor could they assume that if someone didn't own a poodle then they must be male.
There's also a number of markers and "treatments" that are still unproven or even highly controversial, but various factions within the autism community may push them as if they are proven and insist that they are (when really they either don't work at all, or only work for a select subset of autistic people for reasons that have little to do with them being autistic). That sounds like the sort of people you have run into, people who will swear up and down that something is absolute and proven when it's not.
Most of the things that a real diagnostician will do in diagnosis will involve things like taking a history, and doing certain kinds of testing.
This may or may not involve brain scans, but if it does, a good diagnostician will not use that as the only factor. They can use it to see if certain things point to autism, or to rule out other conditions, but they can't just diagnose autism on the basis of a brain scan alone. If there's a brain scan that looks "autistic" and no sign of the person actually being autistic, or a brain scan that looks "non-autistic" and every sign of the person being autistic, the person would pay more attention to whether the person actually seems autistic than to whether the brain scan shows up a certain way.
Another area they might do is testing of various cognitive skills. There are more than one pattern of skills that can turn up on these tests that strongly point to autism, but some of them involve actual strengths that autistic people tend to have and non-autistic people do not. (For instance, one subset of autistic people excels on a test called Block Design, and I am very good at that test, so when my SSI examiner saw that, it was one way of confirming that I was genuinely autistic, since you can't fake being good at it. Not all autistics are good at it, but being really good at it in comparison to other parts of the test is a strong sign towards autism.)
The blood tests and stuff they talk about are very iffy indeed. If there were really a blood test for autism everyone would know about it because a lot of doctors would have a lot less work to do and they'd like that.
For reference, I'm diagnosed, but I think self-diagnosis (or self-understanding of official diagnosis) counts for more actually in a way. It was years after I was diagnosed that I actually understood that I was autistic, and why, and so forth, the way that some self-diagnosed people have already come to that understanding because they've thought more about it. Official diagnosis may be better for services but without understanding of it on the part of the person (whether officially diagnosed or not) it's kind of useless for self-understanding.
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"In my world it's a place of patterns and feel. In my world it's a haven for what is real. It's my world, nobody can steal it, but people like me, we live in the shadows." -Donna Williams
30 Dec 2006, 12:57 am
