From: jason 21/06/99 1:05:02 Subject: left and right handers post id: 18689 are people born being left or right handed? or is it developed? how come cricketers for example bat left handed and may through right handed? is it possible to train urself as a left hander if u r a right hander, so that it will be as good as u preffered right hand? is it the same for left footers and right footers is that related to the hand that u use is it true that 1 out of 9 people are left handers?? From: andy 21/06/99 1:13:59 Subject: re: left and right handers post id: 18690 My mother is an identical twin, and is left handed, while her twin is right handed. She is a teacher (they both are) and she tells stories of growing up when her teachers used to tie her left hand behind her back, or hit it with a ruler, as left handedness in writing was considered "wrong"... From: Dr. Ed G (Avatar) 21/06/99 1:40:22 Subject: re: left and right handers post id: 18692 I suspect it's a classic example of something which is biological (as opposed to learned) BUT NOT HEREDITARY! I wouldn't be at all suprised if left and right handedness was simply a result of developmental noise during the development of the foetus in the womb. Developmental noise is one of the things that leads to variation between people... it is the thing that means identical twins have different fingerprints. Developmental noise is very rarely talked about in the media by either scientists or science communicators, because it cannot be controlled, is not straightforward or easily empirically studied or explained, and challenges the notion that we'll ever be able to completely get a handle on congenital diseases (only a fraction of which is genetic) or be able to have any control over anything but the most superficial of traits in our offspring (a fact which I personally find very reassuring). Take musical genius, for example. It is amazing (given the profound influence popularly attributed over such things to genes and heredity) how few musical genius's were born of musical genius's, or who sired musical genius's. Beethoven is a classic example (oft quoted by anti-abortionists) of a genius who came from what might be characterised as "poor genetic stock". It is not unlikely that, like perhaps left handedness, such genius is not the result of determined genetic factors OR the right environment, but the result of a freak occurance of just the right neural connections in the brain by purely random factors during the development of the individual in the womb. Soupie twist, Ed G. From: Chris W (Plebeian) 21/06/99 9:50:56 Subject: re: left and right handers post id: 18710 If left/right handedness is driven by developmental noise then there must be a strong pre-existing bias to right-handedness. If there were no pre-existing bias then surely we would expect to obtain something like a 50-50 split rather than the lopsided (90-10 ?) split we have between right and left handers. Since handedness is hardly a disease that needs curing (and therefore profitable) there is not likley to be much research in the area. Perhaps the sequencing of the human genome will uncover something. From: steve(primus) 21/06/99 11:29:03 Subject: re: left and right handers post id: 18715 A recent article in New Scientist discussed this issue and the latest thinking is that left handedness is genetic, but it is a "switch" gene that can either turn on or not. This explains the different handedness of some identical twins and also gives a worldwide population of lefthanders of 12 and a half percent. For cricketers, why not follow the advice of Stephen Potter (One-upmanship etc). Teach yourself to bat both right and left handed and change after each ball. It's not against the rules any more than changing from bowling over the wicket to around the wicket - but it really upsets the fielding side. From: Cam (Avatar) 21/06/99 12:12:23 Subject: re: left and right handers post id: 18724 "Since handedness is hardly a disease that needs curing… " It was when I went to school! Like Andy’s mum, I’m naturally left-handed, but was forced to write with my right during my early school years. I remember left handedness being described as “disgusting bad manners” and worse. As a consequence, I’m now right handed. I also had some learning difficulties as a kid. I often wonder whether having to change hands was related to my problems with literacy. Incidentally, I can still write left handed after all these years, but I feel paranoid doing it. I keep looking over my shoulder to see if some hideous old bag is going to sneak up behind me and slap me around the ears! From: Phil Cole 21/06/99 14:11:46 Subject: re: left and right handers post id: 18735 I think you can train yourself to do things with whichever hand you want, it might just take a bit longer. i am right handed, but i eat "left handed", just because that's the way i've always done it, and eating "right handed" seems awkward to me. I also have several friends who are left handed, but, due to the expense of left handed guitars, play guitar right handed, without difficulty. cya Phil "Life's a Big Banana Sandwich!" From: steve(primus) 21/06/99 14:52:44 Subject: re: left and right handers post id: 18741 Left handed guitars? Is that like a left handed toothbrush? What expense (apart from a little time) is involved in stringing the guitar the other way round. I have two left-handed brothers and they were alays restringing my guitar until they got their own. On Cam's point, while our society has, at last, accepted left-handedness as a variation of the norm, there are many in the world that don't - which is why it is so difficult to gather statistics on left handedness world wide. King George VI was a natural left-hander, forced to become right handed. It is thought that his stammer was attributable to this. The word "sinister" merely means "left" in Latin, but much of its modern meaning in English was bestowed upon southpaws. From: Chris W (Plebeian) 21/06/99 14:58:08 Subject: re: left and right handers post id: 18742 I'm not a muso, but on an electric guitar there is a bar and several knobs that have to move for left handed operation. From: steve(primus) 21/06/99 15:09:14 Subject: re: left and right handers post id: 18744 Sorry Chris, never thought about electric guitars, I've ony ever owned classical guitars. The knobs on electric guitars are not used all the time during playing so having them upside down would not, I feel, be a problem. With the bar, surely unscrewing it and putting it on the other side would work? failing this, is the reluctance by the manufacturers to provide left handed guitars at the same price as right handed guitars something that could be taken to the Anti-discimination Board? From: helen 22/06/99 13:01:09 Subject: re: left and right handers post id: 18919 just a few bits on lateralisation and handedness - there may be a link between left-handedness and dyslexia, but I've never seen any research which supports the idea. Since your left hemisphere generally takes care of sequencing stuff (especially in time) and has been linked with following social rules and conventions, things like reading (sequences of letters) and spelling (rules for these) might get a bit messed up if you had problems here. However, as specialisation or dominance of hemispheric functioning (or problems with it) hasn't been linked conclusively with left-handedness, I think Cam's theory about having had to work extra hard at learning all this stuff in the first place (even if our newly-enlightened school system wasn't actively monstering you) is the better explanation for reading/writing difficulties. As for the creativity link, there's also a major problem with evidence here: While left-handers are over-represented in extremely creative ("genius") populations, they're also over-represented in populations of schizophrenics and psychotics. However, when you take a random sample of left- and right-handers, you're no more likely to find (even mildly) creative people or potential psychiatric patients among the lefties than among the righties. Probably something else (or more likely, several something elses) is at work here, which just happens to also be associated with left-handedness in some cases ( = a spurious correlation). The left-brain/right-brain stuff which pops up so frequently in pop psych pulp is largely an over-extension of "split-brain" studies done in the 60's. A proposed treatment for severe, untreatable epilepsy was to "split" the hemispheres of patients by cutting through the corpus callosum, the body of neurons which connects the two hemipheres and allows them to interact. This meant that seizures (excess electrical activity) would be confined to the hemisphere they orginated in, reducing the severity of the fit. Many of the "split-brain" patients reported experiencing two "selves" (e.g.: one woman had trouble dressing in the morning, as her left hand would reach for one set of clothing, her right hand another), which was taken by some to mean that all of us have two separate brains, and that the left somehow "dominates" over the right for most of us - a fairly wild and woolly conclusion, to say the least. A better representation is that we all "think" with both sides, as any coherent response to the environment usually requires co-ordination among functions located on either side of the brain, but that there are individual differences in how well-developed some of these functions are. Not everyone agrees with this, but in my experience the touters of left/right dominance are usually trying to sell something (usually expensive training courses). try http://www.cycad.com/cgi-bin/Brand/quotes/q19.html" here for scads of stuff on lateralisation of hemispheric function and handedness: it's a bit overwhelming, but gives you an idea of how much disagreement there is on the topic. :-)helen (bringing confusion where no confusion was before) This forum is un-moderated. The views and opinions expressed are those of the individual poster and not the ABC. The ABC reserves the right to remove offensive or inappropriate messages.