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Dyslexia Seen In Brain Scans of Pre-School Children
dryriver writes "Brain scans may allow detection of dyslexia in pre-school children even before they start to read, say researchers. A U.S. team found tell-tale signs on scans that have already been seen in adults with the condition. And these brain differences could be a cause rather than a consequence of dyslexia — something unknown until now — the Journal of Neuroscience reports. Scans could allow early diagnosis and intervention, experts hope. The part of the brain affected is called the Arcuate Fasciculus. Among the 40 school-entry children they studied they found some had shrinkage of this brain region, which processes word sounds and language. They asked the same children to do several different types of pre-reading tests, such as trying out different sounds in words. Those children with a smaller Arcuate Fasciculus had lower scores."
They lie awake all night wondering if there really is a DOG!
What I got out of the article was not that 'scans could allow early detection and diagnosis', because deploying brain-scans on children to 'detect' a disorder like this is ludicrous (due to the low base rate and high cost of imaging). What I got was that there are 'pre-reading tests' which are apparently useful to detect dyslexia - otherwise you couldn't correlate the brain imaging results with the results of those pre-reading tests, and then call the imaging a 'dyslexia test' right?
Hell, maybe the researchers could develop a battery of pre-reading tests and then look at the correlation of the tests to the smaller arcuate fasciculus to choose good diagnostic tests. Assuming that the smaller arcuate fasciculus is actually causal in dyslexia, of course.
(Note: I am broadly cynical about correlational brain imaging research such as this. It can be good. It is almost invariably overstated.)
Einstein had dyslexia. For most people and business, college (and school in general) is about meeeting deadlines and following a schedule. For the minority that enjoy learning and have done so their whole lives, college is quite tedious.
My dyslexia forced me to work harder in school at things others found easy. I was confused for a few years until I realized not everyone had my issues. Once I adapted, I started jumping grades and moving ahead. There are things about it that can be leveraged in terms of learning, after all.
Finding issues like this out early can be a blessing or a curse depending on how the parents and the school system react. If it's used to hang a 'problem learner' sign on a kid and just stick them in a corner, I say it's a curse. If it's used to support a tailored teaching environment, it would be a blessing.
A large percentage of dyslexia cases can be corrected through the use of colored lenses. Evidently in these cases dyslexia is caused by certain colors being transmitted to the wrong areas of the brain. Filter out these colors and a person can suddenly start reading. See irlen.com for more information. I am in no way affiliated with the site but know from personal experience that this works.
When we discovered my daughter had a reading problem, I paid for comprehensive tests, delivered the results to the school, (she had severe dyslexia -- the doctors said she probably wouldn't ever read past third grade level) and was told flatly by school officials that they didn't recognize Dyslexia as a condition. That their diagnosis (a school giving a medical diagnosis? never mind...) was that she was hyperactive and had a problem with authority. They suggested Ritalin. I pointed out that an independent psychologist hadn't found any signs of hyperactivity. They stuck to their guns.
So, maybe I'm being overly cynical, but I suspect this new test will just give them another datum to ignore.
But who knows, maybe it depends on the school system.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
Sure, but did the kids later get diagnosed with dyslexia? Oh, didn't follow them that long? So we have an interesting observation pretending to be a diagnostic tool.
What's wrong with labels, then? You're acting like they're something bad, but you're not actually explaining why. Certain labels just happen to help with knowing how to treat a person in some situations, like e.g. my ex is highly dyslexic and therefore has trouble with written content; if you're communicating with her but don't know about her "label" -- as you so eloquently put -- you'd think she's either retarded or doesn't bother to follow the communication because she keeps misinterpreting what's being said or reading it completely wrong. On the other hand, if you know about her "label" you'll know to write your sentences slightly different so they may be easier to interpret and if she still misreads what's being said you can just ask her to re-read the thing.
Personally I feel there's nothing wrong with most labels, it just seems fashionable to complain about them.
As you're probably aware, MRI != ECG
An MRI requires a huge amount of power to run, because it needs to power an electromagnet capable of magnetically aligning atoms in the body. For one mobile scanner, this requirement is 200 amps at 480V on three-phase power. That doesn't specify actual consumption, true, but the magnet needs to be repeatedly used throughout a scan, which can be 20+ minutes.
According to a friend of mine (who a imaging researcher at an Australian hospital) a decent scanner will have a purchase cost of >$1m.
What's wrong with labels, then? You're acting like they're something bad, but you're not actually explaining why.
Labels, what could be wrong?
1. You are categorized that is what you are, and when labeled, you tend to stay there.
A co-worker's wife was a teacher. One day at a wedding reception she told me that she had excellent skills at labeiling chilren after a few seconds, and was very proud of how well she did it. She said she was always right. After speaking with some other parents, it turns out when she lableed some child a loser, she made damn well sure the child became a loser
I might have dismissed it, except that I had a teache like that. She picked one male child every year to be "the bad boy". And boy howdy did she let me have it when she decided I was the bad boy. My most amazing experience with her was when she told the parents about "bad stuff" that I was doing in school. And my parents believed her. Took till well out of high school to heal those jabs.
So yeah, I don't like labels. Labels, especially lables of presumed deficiancy are the stock in trade of people who lack the intellectual ability to understand that people are people. I have no toleramce for them. They are mentally lazy.
Certain labels just happen to help with knowing how to treat a person in some situations.
Oh, yes, how to treat people. I've worked with people with "ADHD", and "Aspergers". I put those in quotes, because I'm not all that sure that they sohould be conditions, and of the odd things that happen once you are diagnosed. You are treated as if you are stupid. Every personal problem is attributed to your deficiency. How do I know? Because of my life experiences, I don't treat them as anything . They all kind of like it. Aspergers dude says something outrageous, I laugh, or tell him to knock it off. Most folks just don't understand. When you're labeled, people tend to talk to you as if you are mentally challenged, or suffering from dementia. Neither is a condition of those two labels
This is going to be a really big secret I'm telling you, don't tell anyone:
These people that you need to know how to treat? Treat them like a normal person.
With all due respecrt to the normal people in the world, Normals really have the market covered on being unctious condescending assholes. Perhaps that should be their label, and we should treat normal people like assholes?
Personally I feel there's nothing wrong with most labels, it just seems fashionable to complain about them.
No doubt you haven't experienced the joy of being labeled. It's a lot of fun. Makes you feel like you are on top of the world. Now go take your Ritalin.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
Yes. There are pre-reading tests that can detect dyslexia, and they are quite accurate. The tests that I know of are trivial to pass for non-dyslexic children, and surprisingly challenging for children who will exhibit dyslexia once they start to learn to read.
They're all about testing how well children can take words apart and put them back together in their head. I attended a presentation on this at the University of Canterbury - which if you're interested you can see here:
http://www.youtube.com/watch?v=ZzyZquJ4260
I have two children with dyslexia, and one without. Of the two with dyslexia, one is quite a bit more severe than the other. I would judge that they are each of more or less equal intelligence, but the one with the severe dyslexia can barely write. He can talk intelligently, use his fairly extensive vocabulary, follow complex lego instructions, understand complex language when it's spoken. But he finds it very difficult to read and write.
Dyslexia exists. Get over it.
ADHD - don't know. High-functioning autistic? Sounds like a contradiction in terms to me. But Dyslexia? Trust me mate, it exists, and if you have it then you will have severe difficulty in learning to read and write. End. Of. Story. I presume from your dismissive attitude that you don't have it, in which case more power to you.
There's no drug for it ether. Sure, I'm very suspicious of problems that have quick fixes you can go out and buy - Dyslexia doesn't have any of that. There's no cure, it's just how you are. You will always struggle with reading and writing, but other aspects of language will be unaffected.
If you check out the actual reporting from the authors (here for abstract http://www.jneurosci.org/content/33/33/13251.abstract?sid=bb49e635-09a9-4719-8462-cf027b122652) you can see that they tested three predictors for dyslexia on children who had not yet received reading lessons. Without making any claims of observing dyslexia, they noted that the size of the arcurate fasciculus is positively correlated with scores of 'phonological awareness' and no correlation with 'rapid naming' or 'letter knowledge.' Perhaps a linguist or clinician could help elucidate what those tests are actually measuring.
It could be that dyslexia is a grouping of somewhat different brain/processing abnormalities that have similar behaviors. If that is the case, then brain imaging of the size of arcurate fasciculus could predict whether treatment aimed at increasing phonological awareness would have any effect. If you haven't had an intro neuropsych course you may not have heard that the arcurate fasciculus is a primary connection between auditory cortex and motor representations - thought to translate hearing into replying. Folk who have damage to this fiber tract are typically unable to repeat back to you what they just heard. The auditory and visual conduits run in parallel in this part of the brain, so it may have bearing on sequencing of writing, not just spoken words.
i don't know karate, but i know ca-razy
My daughter has reading troubles that I believe were consistent with dyslexia. We voiced our concerns to the school and they told us it was a medical issue not a school issue. So we talked with her doctor who informed us that dyslexia was a school problem and not a medical problem. To have her diagnosed officially we would have to had paid a large amount out of pocket and even then the school would not do anything beyond what help she already received in her reading group. If dyslexia is so common I can't understand why it is swept under the rug like it doesn't exist.
As far as I can tell, here in the UK it isn't swept under the rug - schools seem to take it very seriously and provide extra help, and dyslexic people can qualify for government grants for equipment to help them, etc. From the comments I'm seeing here it sounds like the US is pretty backwards when it comes to dyslexia. (And you're right - its extremely common, I know a lot of dyslexics).
http://blog.nexusuk.org
The electromagnet of an MRI (or NMR machine as they were politically-incorrectly called) has a truly humongous field strength (order of 1 Tesla) and it's wound from Niobium-Tin alloy which is superconducting if you put it in a liquid Helium cooled NMR machine. So, you charge it up to the field strength it can bear without quenching, and then you just make sure to regularly top up the liquid Nitrogen (77 Kelvin = -195C) in the large Dewar barrel that surrounds the small Dewar barrel with liquid Helium (4 K).
;-)
It's a cool machine to work with
In order for it to scan and flip the Hydrogen spins in the patient or sample tube you need variations in the electromagnetic field surrounding the probe, but they just do that with radio waves coming in from the sides. You can also do more complicated stuff with magnetic field gradients but I think the gradients are really really small perturbations of the main field strength (in the order of ppm).
tl;dr: the electromagnet of an MRI / NMR is never turned off; that's a minor industrial accident called a "quench" when the Helium and then the Nitrogen boils off and the personnel rapidly leaves the room. I've heard firsthand that it gives a very unpleasant feeling that is difficult to describe.
To be, or not to be: isn't that quite logical, Slashdot Beta?