Autism Diagnosed With a Fifteen Minute Brain Scan 190
kkleiner writes "A new technique developed at King's College London uses a fifteen minute MRI scan to diagnose autism spectrum disorder (ASD). The scan is used to analyze the structure of grey matter in the brain, and tests have shown that it can identify individuals already diagnosed with autism with 90% accuracy. The research could change the way that autism is diagnosed – including screening children for the disorder at a young age."
Or.. (Score:3, Funny)
Counting the number of first posts you get on slashdot
Re:Or.. (Score:4, Funny)
Re:Words (Score:2)
With our without counting "kkleiner writes"?
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There are 440 characters in the text of the summary plus the introduction you speak of. Disregarding ends-of-lines or the actual URL embedded in the text.
Definitely.
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So let's just hope it will not be used for mass screening...
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If we’re asking, “If I have autism, will the brain scan find it?,” the answer is an encouraging 90% “yes.” But if we change the question to “If the scan says I have autism, do I have the ASD?,” that number plummets to something like 5%.
In other words, this method is roughly as accurate as:
bool hasAutism(void *data) {
return (rand() % 20) == 3;
}
Base rate fallacy (Score:5, Informative)
Not really -- the problem is with the base rate fallacy [wikipedia.org]. Suppose that there's a test that will tell you whether or not you have a disease with 99% accuracy: if you have it, you're 99% likely to test positive; if you don't have it, you're 99% likely to test negative.
Now, you get a test and it's positive. What's your probability of having the disease?
The answer is, "There's not enough information to answer the question." The missing piece of information is the "base rate".
Suppose that 50% of the people have the disease. Then in testing 1 million people, 500K will have the disease, of which 495K will come back positive (true positive), and 5K the test will come back negative (false negatives). 500K will not have the disease, of which 495k will come back negative (true negative), and 5k will come back positive (false positive). If the test came back positive, you're either a true positive or a false positive. Since there are 500K positives, and 495K of those are true positives, your chances of having the disease are 99%.
Suppose instead that 1% of people have the disease. Then in testing 1 million people, 990K will not have the disease, and 10K will have it. Of the 990K, 980K will come back negative (true negative) and 10K will come back positive (false positive). Of the 10K, 9900 will come back positive (true positive), and 100 will come back negative (false negative). There are 19,900 who tested positive, of which only 9900 (less than half) actually have the disease. So if you tested positive, your chances are about 50%.
So even if the test itself is very accurate (and I think 99% is pretty accurate), if the base rate is low enough (and in autism I believe it's still less than 1%), a positive reading may not be conclusive. You'd have to correlate it with other symptoms to make sure.
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mod parent up.
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The previous discussion is why the base rate fallacy is so dangerous. According to wikipedia, the base rate for autism is 6 / 1,000. That means a random child has a 0.6% chance of having autism. A test that raises that to 5% is a huge improvement (almost an order of magnitude).
Re:Base rate fallacy (Score:4, Funny)
A test that raises that to 5% is a huge improvement (almost an order of magnitude).
Because of course we want a test that increases the child's chance of having autism. :)
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Err .. no. And if you ever did a side-by-side comparison, you'd know.
"Any kid under the age of 10" doesn't scratch wallpaper off the wall until their fingers are bloody, for example. Or spend an hour or two bouncing in circles and shouting "La-DEE la-DEE la-DEE" at the top of their voice.
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If your breathing sounds like "laDEE laDEE laDEE laDEE ..." (at about 2/second), yeah, maybe.
Unacceptable false positive rate (Score:2, Insightful)
Even if you used this as a basis for further testing, You're still putting 10 families through the stress of comprehensive testing for autism for no reason for every 1 family whose child actually has the condition.
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Bleh, I'm not used to actual good reporting on "a new totally amazing test!!!" stories in the media.
Re:Unacceptable false positive rate (Score:5, Insightful)
MRIs are expensive, and autism-like behavior is obvious enough that you can narrow down the group of people you're going to test significiantly before you start testing. Also, for families with one or more kids with behavioral disorders, a 15-minute test usually doesn't qualify as "stress", at least not compared to all the other crap they have to go through.
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I wonder how many false positives you can give to a family before they stop believing in modern medicine.
"Your kid is autistic!
No, wait, he wasn't. But he's got ADHD! Nope. A tumor! Nope, that's not it.
*five hours later*
The pox! Nope. ... Plutonium poisoning! Yeee... Nope. ...
Does your kid have any south asian prostitute friend?"
Re:Unacceptable false positive rate (Score:5, Funny)
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When my son got a MRI as part of being diagnosed as autistic, it was not a simple 15 minute test.
They had to put him under before testing (they have to lay still for 15 minutes) which is somewhat stressful and he had to observed for a couple of hours after the test before we could take him home.
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Ahhh, so that's why it took till my early twenties before someone even thought of looking in that direction.
No, it's because Asperger Syndrome wasn't "official" with the APA until the mid-nineties, so most doctors either disregarded it as a possible diagnosis or had never heard of it other than a mention in a medical journal.
Re:Unacceptable false positive rate (Score:5, Funny)
Then I must have Asperger's too. I don't go to church, I don't watch sports on TV, I believe that men went to the moon, I believe that heavy use of fossil fuels is causing global warming, and I believe fluor is good for your teeth.
Maybe I was vaccinated when I was a kid.
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Unfortunately, making "self-centered"/immature/blanket statements like that is a hallmark of the condition. No real reflections over other's perspective, just the intellectual realization that other people are different, and do "stupid things" for seemingly no reason.
Sort of/not really. I suspect that most adults with more than slight Asperger's have learnt *not* to make those statements, while those of us without ASD can make them for humourous effect because we can expect that they will be understood as such.
I used to work with a guy with Asperger's. He surely had empathy, but for instance he had difficulties with following a casual conversation in a group because he missed all the little cues which you and I catch as a matter of fact. If the topic changed due to a no
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Oh noes ... I caught teh Asperger's from teh Slashdot.
(Apologies to anybody who actually has this condition.)
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Part of the official diagnosis criteria of any mental disorder is that it needs to cause a significant problem with normal functioning. If it does not cause a problem for you, you wont fit the criteria.
This is what I think is great about the brain scan test - it can show that people with "significant problems with normal functioning" have marked structural similarities to many unusual people who do not have significant problems, or are high performers. Rather than chucking the kids in a dark closet because they got a label that only applies to failures, you can identify them as someone with potential to do well, _if_ they can get past the developmental challenges.
I think part of what makes humans so d
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If the autism is severe enough to require treatment as early as possible, then there will be symptoms well before the kid is a year old.
Much higher (Score:5, Informative)
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It doesn't mean that their brains are structurally the same as society at large.
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its actually much higher than that. What you're quoting is that 1 in 10 people with autism and given a false negative.
Its actually much worse. Out of 10,000 children, 1980 would be found positive, out of which only 90 would have the disease.
So only about 5% of people who tested postive would actually be autistic.
It says this in TFA.
What, though, if the bolded assumption above is false? We're simply making an assumption here, aren't we? I mean, there's not any non-behavioral criteria being used to specifically state that the 'disease' isn't present, right?
What if, somehow, those 1900 or so other people do have the 'disease', but they are somehow coping with it as to not have any discernible symptoms? Take as an example the number of people with Type II diabetes who are unaware of it. It isn't as if the blood sugar counts are someho
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Out of 10,000 children, 1980 would be found positive, out of which only 90 would have the disease.
Actually, about 60 (0.6%) will have ASD according to Wikipedia. Also, you'll be reasonably sure that, say, 9600 of the 10000 don't exhibit behaviour consistent with ASD at all (number from thin air). Checking all 10000 doesn't make sense, most will have a perfectly normal development from early age.
On the other hand, if they really have found a reliable biological marker (no false negatives) which indicates ASD, you could test those 400 you suspect have some difficulties which might indicate ASD. Fringe cas
Re:Unacceptable false positive rate (Score:5, Insightful)
As you said, this will just be used for further testing. Treatment for autism is very similar for other behavioral abnormalities, so not much will change for the families. If a child has already been singled out for further testing by their teachers/counselors/doctors/family, this will just be another in a set of tests to help further treatment. A child with EBD or Autism receives much of the same interventions at school and home. The interventions are extremely specific to each child; knowing that this child may be autistic gives parents, teachers and doctors a more focused approach to treatment. It directs which bag-of-tricks to start working from. Fortunately, if the child is not actually autistic, but has say Pervasive Development Disorder (PDD), many of the same interventions such as remedial communication skills and socialization skills can be used.
It's not like this test puts a kid into a box with only one possible medication or treatment is offered. Each child's treatment is developed with the parents, teachers and other professionals. Some kids need headphones to walk though the cafeteria, some kids need a special squeeze ball, some kids need slow subtle introductions to complex social situations with highly scripted encounters to help them understand what is going on. This is true for the whole spectrum of EBD/autism disorders. Being able to scan a kid that might be autistic just gives everyone a much better starting place. They have a greater chance of successful treatment if they know which bag to start with rather than just grasping at straws.
Real Humiliation (Score:5, Insightful)
Therapy's not humiliating. Hell, OT's kinda fun.
Real humiliation is when you're growing up and all the interactions with your peers blow up in your face due to your mind-blindless and inability to read body language or understand personal space, and your classmates ostracize you because they think you're weird, and you don't know what's going wrong. And since there's nothing you know of (because your'e undiagnosed) that differentiates you from your peers or explains why this is happening, you conclude you're getting ostracized because you're some doofy, idiotic, bad person. That, my friend, is real humiliation.
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You know, if you'd just apply yourself and try harder, you'd be more successful. ;-)
Re:Real Humiliation (Score:4, Informative)
I went through exactly that. Being as smart as I am, people just figured that I shouldn't have problems. But when reading body language and figuring out social boundaries is a strenuous mental exercise, and doesn't come naturally or work subconsciously as it does with most people, it's exhausting, and very frustrating when you keep screwing up, unable to figure out all the rules. The humiliation never completely goes away, but you get used to it after a while.
I'm 28, and I just figured out I have Asperger's Syndrome about a month ago. Not knowing until now has caused me a huge amount of grief. If I had known in kindergarten, it would have helped. Even then, I wasn't relating to the other kids -- and I never knew why I couldn't make friends. It wasn't a lack of trying.
"Well functioning" individuals with autism spectrum disorders can get better. After a while, we build up the "rules" for social interaction. The mental effort never goes away, but like learning to play chess, the basics do come more naturally after a while. It'll never be like riding a bike. To this day, I have trouble continuing a casual conversation. I'll never really connect with anyone that isn't a nerd. I'm okay with that.
In a sense, we are actors, life is a stage, and we do all our own stunts. The biggest problem well functioning individuals on the autistic spectrum face is coming across too normal, so that people attributed our odd behaviours as intentional and not to an innocent lack of understanding. We can learn, but because we usually highly intelligent, it's not obvious we need guidance or help.
Discovering that I am on the spectrum has brought a lot more of the humility I had already begun to learn in an effort to relate to people. My high intelligence made me arrogant as a kid. I used to look down on people if they weren't as smart as I am. It took me a while to recognize they had talents in areas I didn't. Now I know why my abilities are so different than those of a normal person.
I am blogging about being an aspie [aspieaspects.com], too. I'll probably repost this there later.
I'm not exactly impressed... (Score:5, Informative)
So it only has a 4.5% true positive rate. Great.
Re:I'm not exactly impressed... (Score:5, Insightful)
Yep, but that might make it a useful *screening* tool rather than a *testing* tool. You'd then go do proper (ie more specific) tests.
I can get a 99% correct diagnosis rate on autism just by going "not autistic" every time.
I've read the original paper, and its based on a sample of 20 normal and 20 autistic people, I might have another read to see if they've done multiple tests and only picked the significant one. Search for the poster about fMRI responses in a dead salmon for more info...
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Well, the fact that the false negative rate of 10% is worse than it's false positive rate of 5% doesn't really impress. Also MRI is not cheap. Screening tests that are actually useful are cheap and have very low false negative rates. This has neither.
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The pojnt of the test was to see if it was even possible to detect someone with autism. That's all.
Apparently it is. More refinement needed.
If peoplem started using it right now as an actual yes/no test then everyones complaints would be justified.
Worse yet... Re:I'm not exactly impressed... (Score:2)
The article doesn't show the false positive rate on people that have been diagnosed NOT to suffer from autism...
I hope it doesn't say 90% of them are autism sufferers...
Re:I'm not exactly impressed... (Score:5, Insightful)
So it only has a 4.5% true positive rate. Great
Indeed, it's significantly worse than my (99% true rate) autism diagnosing rock that evaporates if an autistic child holds it.
And my rock takes much less than 15 minutes.
Re:I'm not exactly impressed... (Score:5, Funny)
Hmm, I think I might be autistic myself judging by my inability to resist making this post.
Re:I'm not exactly impressed... (Score:5, Funny)
Hmm, I think I might be autistic myself judging by my inability to resist making this post.
Here, hold this rock for a second.
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Here, hold this rock for a second.
Autistic kids rock.
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excellent post. Sadly I don't think most people here actual understand what false positive actually means.
In fact I am beginning to think your post with it's facts and mean will confuse most people here and because them to raise there hands in the air and grunt at each other.
At least they are only one monolith away from achieving sentience.
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oblig. (Score:2)
Lisa, I want to buy your rock.
Secondary diagnostic test (Score:2)
Hey, an example of applying Bayes' Theorem (Score:2)
and I'm not exactly impressed... (Score:2)
with your lack of comprehension.
Lets make it simple for you:
Test is devised to find out if MRI can detect autism.
It can detect people with autism with a 90% rate.*
Refinement is needed.
Your complaint is like going to 1912 and telling Goddard since his first rocket liquid fueled rocket won't go to the moon, his research is useless.
It's a good discovery that has promise.
*this does NOT mean 9 out of 10. IT means that the closer you get to edge cases the more likely it will fail.
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People are (sometimes) upset about the fact that a disproportionate number of blacks end up in prison - but I don't think the number is anywhere near 4.5%.
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Tests and treatments need to do more good than harm. Even if a comprehensive testing regime catches someone who would otherwise be missed, it's not worth it if the 100 false positives make life horrible for the people affected.
Autism, is it really a disease? (Score:4, Interesting)
It is interesting, but unsurprising, that they found that ADHD and autism had no link thus far. Based on the symptoms I expect we'll find that if ADHD exists at all that it will be localised around control, while autism is localised around right/left brain communication.
Re:Autism, is it really a disease? (Score:5, Insightful)
While people who suffer at the extreme ends of the autistic spectrum would have difficulty maintaining a society, some of the more moderate autistic individuals are leaders in engineering, technology, and science.
You could say the same about cancer. Some leaders in engineering, technology, and science have cancer. That doesn't mean cancer may not really be a disease or that a neoplasm may simply be the next step in our evolution.
It has become fashionable among nerds to identify with Dustin Hoffman's portrayal of Rainman to the point anyone who is even remotely socially awkward or left brain oriented to be called autistic, followed by the implication that autism fills an important role in society. The reality is somewhat different. With a few famous exceptions, patients tend to have trouble taking care of themselves - many are profoundly disabled - while actual leaders in engineering, technology, and science tend to have normal mental health. (though many of them may be assholes, but that's another story)
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You develop cancer whether or not you're a highly intelligent creature. Even dogs and cats develop cancer. There is no correlation between higher IQ and cancer (if anything it would be inversely related since lower IQ could mean you're more prone to do the low-paid, dangerous jobs around known carcinogens)
Autism Spectrum Disorders are a range of disorders (not diseases) that you're born with, not something you develop (at least that's the current consensus). ASD-affected people however are either very high
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It has become fashionable among nerds to identify with Dustin Hoffman's portrayal of Rainman to the point anyone who is even remotely socially awkward or left brain oriented to be called autistic, followed by the implication that autism fills an important role in society. The reality is somewhat different. With a few famous exceptions, patients tend to have trouble taking care of themselves - many are profoundly disabled - while actual leaders in engineering, technology, and science tend to have normal mental health. (though many of them may be assholes, but that's another story)
Do you know anyone who is autistic? I think not. You are counteracting the bullshit of Rainman Autism with the bullshit of Gilbert Grape Autism. The truth is that like all people, most Autistics are somewhere in the middle. I am very involved in Adult Autistic skills classes (where we teach life skills and coping strategies), and my child is Autistic, most of his friends are Autistic (shocking I know, how can he have friends if he is a mouth foaming invalid).
I know it can be frustrating to people who
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I know many people all over the autism spectrum.
The posters point is correct. That it's become fashionable within certain geek cultures to claim to have Asperger's syndrome.
The last paragraph you right was completely irrelevant to the post. IN fact, is reeks of a standard reply always written even if it shows a complete lack of comprehension regarding the point to are adressing.
It's in interesting that you seem to write negatively of your 80's treatment, yet they seems to have worked.
I am old school enough
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Autism is not prevalent at all. The fairly recently introduced class of "autism spectrum disorders" however are, but that's because it's generally a weasel term for "we don't know what the problem is and in fact there may not even be any problem, but let's put a stamp on it anyway" (I'm not a psychiatrist, but my father is and I talked about it with him). My *personal* opinion is that many people who are somehow not very socially minded or otherwise feel like an outl
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""we don't know what the problem is and in fact there may not even be any problem, but let's put a stamp on it anyway" (I'm not a psychiatrist, but my father is and I talked about it with him)"
Yeah right, like this qualifies you for saying anything about it. Real severe autism certainly does exist and that there is quite strong evidence that their is in fact a spectrum. See temple grandin:
Now just watching her now she seems "more normal" but you can tell their is something off about her right away and if
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""we don't know what the problem is and in fact there may not even be any problem, but let's put a stamp on it anyway" (I'm not a psychiatrist, but my father is and I talked about it with him)"
Yeah right, like this qualifies you for saying anything about it.
The above is basically what he told me.
Real severe autism certainly does exist
Of course it does, I never denied that.
Like many things autistic spectrum disorders are over-diagnosed
And that was basically my (father's) point (although he believes it very much over-diagnosed).
Like many things autistic spectrum disorders are over-diagnosed but why why people are diagnosed on the autistic spectrum is in the first place is to get help.
The point is that the fact that someone could use help does not necessarily mean that they suffer from a psychiatric disorder (although maybe for some people it's required to get over the mental barrier to seek help). But just like not diagnosing a problem is bad, starting to diagnose every deviation from whatever is perceived as "the nor
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"The point is that the fact that someone could use help does not necessarily mean that they suffer from a psychiatric disorder"
Yes but disorders are defined in terms of functioning within a society, i.e. without help many people would likely off themselves or possibly in worst circumstances turn to crime, etc.
There may be "nothing" apparently wrong with them but obviously their developmental history took a wrong turn somewhere. You have to understand that people end up in psych system because collectively
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You have to understand that people end up in psych system because collectively we are in denial and don't give much of a fuck about the fate of one another
I'm sure that holds for a number of people (there are also people whose relatives/friends did try to take care of them and simply were not able to handle it). However, I think that defining psychiatric disorders with the purpose of getting socially vulnerable people in the psychiatric system is a very bad approach (now /there's/ a practice that may easily induce people to consider psychiatry to be nonsense).
I'm not saying that such people should not get help, but psychiatry simply does not seem to be the ri
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Other times, it's a case of mental disabilities forcing people into certain career paths.
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We've probably had people who register in the Autism spectrum with obsessive interests going way back into prehistory.
Certainly if ASDs are largely genetic, there would have been early humans eidetic memory, and other unusual mental abilities. They could have been encyclopedias of knowledge about what
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Well, from all that you've said to this point, what you describe is not all that unusual in most people.
There is a matter of degree, of course, which you have implied is above what you perceive as normal.
The longer I live, the more normal I discover myself to be. YMMV, of course.
Not to imply that it was all in my head or that it is all in your head. I have an approach (set of approaches) to many problems that is different from most people's approaches. If I try to work around that, I usually spend way too m
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With Autism being so prevalent in humans you do have to wonder if it is really a disease or mistake, or perhaps either a previous evolutionary step or our next evolutionary step.
This isn't Marvel comics. Evolution doesn't work that way.
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It's not the prevalent. It's in the media a lot, and the edges have widen. That's not the same thi8ng.
More people break their arm, that doesn't mean it's the next step in evolution.
ADHD does, in fact, exist unfortunately ADHD, and any other diseases, get jump on buy people pushing an ideological position and that confuses people and makes it hard for them to understand what the actual science is.
Also idiots see a child behaving differently so they think it must be the parents fault. sometimes it is, but no
Re:Autism, is it really a disease? (Score:5, Insightful)
With Autism being so prevalent in humans you do have to wonder if it is really a disease or mistake, or perhaps either a previous evolutionary step or our next evolutionary step.
This point gets raised on Slashdot quite often, and it represents in incredible misunderstanding of evolution. Evolution doesn't have steps and doesn't progress in an easily identifiable direction. Genetic features aren't mistakes. They just are. And they are either beneficial in some way or they are not. If there are specific genes responsible for autism and they always cause autism, they would need to spread to a very large fraction of the population to be indicative of evolutionary change. They would also need to be beneficial to reproductive success.
Now it's possible that some of the genes that cause autism are beneficial, but that having too many of them causes autism. It would be difficult to go from that state to an entirely autistic species. I don't see highly autistic individuals finding autistic mates and having large families. Even if they did, the children might not be autistic. We don't understand the genetic and environmental combinations required yet.
If you've had any contact with highly autistic people, you'll know that an autistic species wouldn't survive for long. Fully autistic people (not the ones on slashdot who claim to be autistic but are just lacking in social skills) do not have the skill set to survive alone. Or to recognize that another individual might need help. Or to recognize that another individual has thoughts, emotions, or a different point of view. The savant skills that some autistic people have are rare. Autistic people who can't count past 10 outnumber the "living calculators" by factors of a thousand.
Of couse, Autism isn't "good" or "bad." It just is. But it is hard on families. If a way is ever found to prevent it, I think most people would be happy about it.
woo! (Score:2, Insightful)
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", I certainly don't buy it"
Why not?
And this test was just to see if it was at all possible to detect Autism. Not that it detects Autism in an unknown uncontrolled environment.
Hopefully someday it will not only get good enough to do that, but also tell you where on the spectrum the patient is.
What about prognosis and treatment? (Score:2)
Usually ASD is already "almost" easy to diagnose by other means. While treatment is not at all.
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Yes, all work on prognosis and treatment came to a halt because of this test~
Is there enough Helium? (Score:5, Insightful)
The research could change the way that autism is diagnosed - including screening children for the disorder at a young age.
The thing about primary screening tests is that they have to give false positives, due to high sensitivity and lower specificity. It's ok if the test tells you you have HIV when actually you don't. It's NOT ok if it doesn't tell you you have it when you do. The other thing about primary screening tests is that they have to be cheap. This test is far from cheap and in fact consumes limited resources. In some countries there are waiting lists for MRIs.
Perhaps this test could be used as a secondary screen, if specificity can be proven to be high enough, to screen those doubtful or borderline cases so that they can be correctly diagnosed.
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Resources that could become abundant at the snap of a health bureaucrat's fingers (keeping in mind it takes about 5-10 years and 16 forms to get a health bureaucrat to snap his fingers). Wouldn't help with the expense, though.
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Re:Is there enough Helium? (Score:5, Informative)
I don't understand your reasoning.
That's because you're not a health care professional. Put your personal feelings aside for a second and look at it this way:
I have a population that might have a disease. The symptoms of the disease are not obvious, and there's no easy way to tell who has it and who doesn't.
I have a very specific genetic test (Western Blot) that can tell me if that person's blood contains viral DNA. The test is specific because I am identifying DNA from the virus in question. You can't get more specific than that. However this test does have the possibility of false negatives - the person may have the virus, but I might have gotten a sample that for some reason contains no viral particles. Or the virus may be latent, living in T-cells in the bone marrow right now and not circulating in peripheral blood. NOT finding the DNA does not mean you don't have the virus. Finding the DNA confirms that indeed you have the virus. Also, this test costs a lot of money, and uses a lot of resources - less nowadays than 10 years ago, but still.
On the other hand, I have a very sensitive test, the Enzyme Linked ImmunoSorbent Assay. This test identifies antibodies to the HIV virus down to very very dilute concentrations. It is extremely cheap. It can be done everywhere there's a centrifuge to obtain plasma from a blood sample. However because it identifies antibodies and not the virus itself, it is not a specific test. It's possible that a person have HIV antibodies without having the virus - because they were exposed to it enough to trigger an immune response, but never got an infection (the virus never "took hold"), or by some freak of nature, they have a SIMILAR antibody to something else that is reacting to the test. So thus the false positives - the test says you have it when really you don't.
What we doctors do is we tend to SCREEN the population with the simple, inexpensive test first. Why? Because it's simple and inexpensive. That gives us a new population that absolutely captures all the diseased people, and also contains some false positives. We tell people that there may be a problem but they shouldn't worry about it just yet - but we need to run another test to be sure. YOU DO NOT TREAT PEOPLE BASED ON A PRIMARY SCREEN!
To this new population you administer the second, expensive, SPECIFIC test. This lets you "weed out" those people who are false positives. You tell them congratulations, everything is ok and they probably shouldn't worry. You just keep an eye on them for a year or so to make sure they were indeed false positives and weren't people who for some reason gave a false negative on the second test. Maybe you repeat the test the year after just to be safe. And the rest, the real positives, end up with the diagnosis and the treatment.
So what happens is you administer the expensive test to fewer people, saving time and resources, without letting anyone with the disease slip through the cracks. In the case of autism, presumably the primary screen would be the clinical signs - does the child exhibit autistic behavior and fit the criteria? IF that is the case, or IF the physician isn't sure, then the secondary screen (MRI) would be performed. My doubts are about the specificity of the MRI - will it show false positives - people with MRI changes that don't have autism? If so, then it's possible people will be misdiagnosed and that's a no-no.
As for social stigma, uh, that's what doctor-patient confidentiality is about. I certainly won't tell anyone. It's not my problem if I tell you "listen we ran this test and you tested positive for HIV. It doesn't mean you have HIV though, we need to do a different test to be sure" and then you run around telling everyone you have HIV. I find that patients usually understand things when you explain them properly.
Not exactly conclusive. (Score:2)
Re: (Score:2)
It demonstrates that it's possible.
Refinement is needed to see if it can be useful.
Most publish research is false because a lot of it is just like this: initial tests.
As you know, but other readers may not, the facts that most published results turn out to be false is a good thing.
Very False Positive (Score:2)
"A new technique developed at King’s College London" ...is not a new technique at all. It is an application of an old, in fact the oldest, analysis technique for structural brain MR imaging....
"uses a fifteen minute MRI scan"... a very common, standard MR brain scan, followed by many hours of counting the voxels (volumetric pixels) in the area of interest. Followed by many more hours of the same, to estimate the reliability using inter-rater testing, necessary due to variations in size, shape, density
Early screening is going to fuel the anti-vaccine (Score:2)
...movement.
If this test does mature into a (much) more reliable diagnostic tool, and can be made accurate enough to be useful, early diagnosis will significantly increase the number of children diagnosed with autism.
I'm sure the anti-vaccine, anti-science contingent will completely misunderstand the issue and blame the increase in autism diagnoses on the H1N1 vaccine, or whatever tomorrow's boogeyman is.
Ninety-percent? (Score:2)
Doesn't something like 90% of the population fall somewhere on the autistic spectrum as it is? ;o
suribe (Score:3, Informative)
Distinguish between ASD and HSP? (Score:2)
I'll be genuinely impressed - and eager to put myself under the magnet - if it can reliably distinguish between autism spectrum disorders and highly sensitive people (http://www.hsperson.com/pages/2Aug09.htm).
Re: (Score:2, Insightful)
What are the operators of these machines called technically? Shamans?
They are probably psychiatrists--pretty much the same thing as shamans.
Re: (Score:3, Funny)
Technologists, actually. It's the ones who READ the tea lea...err, brain scans who are the shamans, not the ones who do them. Beware of radiologists with bones through their noses.
Re: (Score:2, Insightful)
Since the main article says exactly that, how can it be inaccurate?
Re: (Score:2)
I can do it more accurately than that. And without any false positives whatsoever! (I might have a few misses, but that's a minority.)
Re: (Score:2)
People were not diagnosed before because the classification is fairly new. Bec