I’d like to know whether the physiologic/neurologic basis of dyslexia is known? Or whether it even exists or it’s just “learning disability”, like low IQ? I mean is it known, for instamce, where in the brain is the “center” for dyslexia or the “center” of correct spelling/reading and if XYZ neurotransmitter is missing/excessive, a person becomes dyslexic? Do dyslexic parents beget dyslexic children? Can a spelling bee turn dyslexic one day? Etc.
[Moderator Hat: ON]
This seems more like a General Question, so that’s where I’m sending it.
David B, SDMB Great Debates Moderator
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Dyslexia seems to run a bit my family, so although I have no real scientific data, I can give you some personal observations. Excuse what may be long post
First of all, believe me when I say this has nothing to do with a low IQ.
I’m not affected much by it myself, usually. The exception is when I’m very tired. Then, the thing I notice most is a reversal of meanings in written words that have opposite meanings, especially if they’re words that denote direction or quality, e.g. east/west, left/right, benign/harmful. Homonyms also give me problems. And once in a while, individual letters or numbers appear to be out of order within a word or group.
As an example, I’ve been reading Lord of the Rings (re-reading, actually, for about the 7th time, a great book). And as all of you know who’ve read it, there are many places in the book where descriptions of the layout of middle Earth are given. The edition I’m reading is the new 7 book box set by Houghton Mifflin.
As I was reading last weekend I saw where this new edition had some of the directions mixed up. As the four hobbits leave Tom Bombadil and set out past the Barrow-downs, the descriptions all through the chapter had the Old Forrest on the wrong side (on the east of the Barrow-downs instead of the west). This bugged me so much I kept referring to the map in the front of the book, and even downloaded some more detailed maps from the web. I could plainly see that the Old Forrest is west of the Barrow-downs. I figured I had found a transcription error in this new edition. So I went to show my wife. As soon as I started to explain to her, and said the words “east” and “west” out loud, I suddenly realized I was mixed-up, and the book was correct.
For about half an hour, the printed word “east” meant “the direction in which the sun sets” in my head, and the printed word “west” meant “the direction in which the sun rises”. I don’t mean that I heard those words in my head when I read “east” or “west”, just that in my head, when I read “east” I was mentally pointing west, and vice-versa.
Note that is only seems to happen with written words. The spoken word filtered through with the correct meaning, even when it was me doing the speaking.
Although a couple of my other siblings have some similar mild symptoms, my younger brother is the “bad” case in our family (and the only officially diagnosed case). I’ve talked to him quite a bit about it. It is always present for him, although it seems to be less severe now then when he was a child and through his twenties (he’s 37 now).
He sees letters as being in a different order than they are. It isn’t as simple as a left/right reversal, or seeing pairs of letters reversed. As he reads, he sees every third or forth word as a jumble of letters in no apparent order. So he has to stop, go back, and read again. This time that word will be ok, and another word will be jumbled.
Needless to say, this makes reading pretty slow. Slow enough in fact, that he hated reading as a child. And we are a family of big time readers. He had a hard enough time with reading that even after he was diagnosed as dyslexic and began some treatment for it, he still dropped out of school at age 16. He got a job and supported himself, he just had no intention of ever going back to school.
Now remember, this kid is smart, and hard working. He soaks up verbal information with no problem. Read to him and he has no problem going as fast as you want to go. Reading was (and to a large degree, still is) just a terrible chore.
About 10 years later, he decided to try again. He took a GED to get his high school equivalency (passed it on the first try with less than a week of study), and got into the U of Utah as a non-traditional student. After about a year, he switched to being a full time student.
It took just over five years, but he not only graduated, he graduated with honors. He carried a cumulative grade point average of 3.8 or 3.9, and had a 4.0 his last two years. He was considered as a valedictorian, and graduated cum laude. He continued on to get his Master’s Degree and was accepted into the graduate program at Perdue.
And all that with a reading speed of about 85 words per minute (as compared to my average speed of 400-500 wpm). During those college years, it would take him literally 12 hours a day to read the material required for class.
He loves to read now, even though it is so slow. Years of practice have helped, but it’s still a chore. But the joy of reading is, to him at least, well worth the effort.
You may have guessed by the above that I’m damn proud of my brother. He is my continuing example of what it means to stick to something even if it’s hard.
To sum up, dyslexia is real, or at least there are real problems that are filed under the heading dyslexia. For us, they are problems with assimilating written text, and don’t seem to effect the spoken word. They are not a result of, or associated with, low IQ or other learning problems. We seem to have had the problem since we were born, and it seems to have gotten a little better past age 30 or so. It seems that something is funny with the part of the brain that interprets written words. Strange but true.
Again, sorry for the long post. I hope somewhere in there was some useful information, anyway.
Ugly
Dyslexia has nothing to do with IQ. There’s a statistic floating round that 60% of kids with IQs over 180 have either dyslexia, dysgraphia or other learning differences. Often highly intelligent kids manage to ‘hide’ their deficits - because they are operating at very high levels, it is not immediately apparent that they have dyslexia.
I think there’s some reasonable research showing a genetic link to dyslexia although the McGuinesses (Reading Reflex and _Why Children Can’t Read) claim dyslexia is a myth and it is all bad teaching, in particular Whole Language and that with early enough phonics, dyslexia won’t happen.
I have always had trouble with remembering which is left and which is right and had huge problems learning how to tell the time, sadly the joy of succesfully achieving that may be denied to todays children and their digital timepieces.
Sometimes the letters stand off the page, like three dimensionally and not on the page itself.Other times I can be partway writing one word and yet finish that word off with another that I am going to use later in the same phrase.
At least those are my reasons for my spelling mistakes.
This forced me to make much greater efforts to read, spell and write than perhaps my contemporaries did but I was not aware of it and Dyslexia had not been formally recognised at the time.
I have noticed that many left-handers like myself (a fundamental leftie if ever there was one) also have some handicap in this regard to a greater or lesser extent.
Perhaps it is just me noticing such things but lefties do have some physical differances and preponderance to certain illnesses if a tv program I saw last year was anything to go by.
“Old MacDonald had Dyslexia
O-I-O-I-Eeee”
I’ll admit that I seem to have a very mild case of dislexia. I sometimes have the same directional gaffs that RJKUgly has, ie I’ll read a description of the layout of some place and be confused by it, and then realize that I’m confused because I had east and west reversed (it’s never north/south that give me problems, only east/west). If I’m writing down a number, sometimes I’ll reverse two of the digits. For example, I might read the number 234.52 and write down 234.25 instead. Similar mistakes sometimes occur while spelling words. Of course, I’m used to double-checking for this type of mistake so I usually catch it. Like RJKUgly, it usually only happens when I’m tired. It never stopped me from reading, however; When I was younger I’d read pretty much any book I could put my hands on. It has nothing to do with IQ, it’s more of a mental fluke where things occasionally get reversed somewhere between reading and comprehending.
I reckon many people have the same very mild problems that RKJUgly and Diceman describe. I transpose digits occasionally. I transpose letters occasionally, but far more when I’m typing. I’m not talking about a simple typo, but an inversion or transposition of part of the word.
In my experience, writing a word that was going to come later in the phrase happens simply because you think faster than you write or type.
It’s understood that there’s more than one kind of dyslexia. Some people have a problem seeing letters, others have a problem decoding them.
Brain activity during reading is slightly abnormal in some people with dyslexia. The part of the visual cortex that normally handles reading doesn’t do quite what it should. This matches with the experiences of those people. For them, it’s a seeing problem rather than an understanding problem. The letters look jumbled, or swimmy.
(I have heard that black print on white paper causes the most hassle to dyslexics. Does anyone have experience of low contrast text being easier to read?)
For other people, their dyslexia is more a problem with decoding the individual phonemes that make up a word.
I don’t think that the causes of dyslexia have been sufficiently researched yet. Glue ear at an early age has been implicated. If the child’s hearing is impaired at the age when he/she is learning to recognise different spoken sounds, the ability to relate those sounds to written letters will suffer.
There is a genetic component, but as with all genetic disorders, you can’t say for certain that “dyslexic parents will beget dyslexic children”
I few years ago, I had occasion to have my eyes tested, and started wearing glasses for the first time at age 38. The doctor told me that I have been slightly farsighted for my entire life, and hadn’t I ever had my eyes tested before? Well of course I had, even way back in grade school. He said that mass screening didn’t really detect farsightedness very well. And then he shocked me by asking me if anyone had ever told me I had dislexia. And yes, now that he mentioned it, I had been put into several reading classes that taught speed reading, mostly focusing on how to get the eyes to move together more efficiently.
So that can be a large part of the problem, just plain old bad vision. Especially farsightedness, which is usually only a problem while reading.