The Puzzle of Left-Handedness (33 page)

Read The Puzzle of Left-Handedness Online

Authors: Rik Smits

Tags: #Science, #Non-Fiction

BOOK: The Puzzle of Left-Handedness
2.73Mb size Format: txt, pdf, ePub

There was considerable fascination for mirror writing in the late Middle Ages, and people tended to confuse it with left-handedness. In 1540 Giovanni Battista Palatino in Rome published a course in calligraphy that became a bestseller. He devoted a chapter of it to
lettera mancina,
or left-handed writing. He was referring to mirror writing, which right-handed people can produce more readily using their left hands.

The confusion had set in well before then. Around 1560, sculptor and architect Raffaello da Montelupo, also a resident of the Eternal City, wrote in his autobiography about his experiences as a young left-hander 50 years before. He wrote:

I will not omit to say that by nature I am left-handed, nor that, finding my left hand more facile than the right, I used to write with it, since my teacher made no objection, being satisfied that my handwriting was good. I have therefore always used my left hand, whether I was writing or copying pictures from the
Morgante,
which we read from at school. As soon as I laid the sheet lengthways to write with my left hand,
*
many people looked surprised; they thought I was writing
all’ebraica
[in the Hebrew manner, from right to left] and that what I wrote would turn out to be impossible to read. I remember one curious event in particular. When I started to write out a receipt for a certain amount for a notary in Florence, I laid the sheet lengthways and the notary expressed doubt as to whether what I wrote would be legible. As soon as I’d written one sentence he picked up the sheet of paper, saw that it was perfectly readable and called out to some ten other notaries to come and look. When the receipt was finished, I wrote a few words with my right hand, because I was well able to use that too, even though I’d stopped using it to write with as time went on. As I’ve said, I draw better with my left hand. Once, as I sat sketching the Arco di Trasi al Colosseo [the Arch of Constantine], Michelangelo and Sebastiano del Piombo came by and stopped to watch me. Now you should know that both of them, although left-handed by nature, did everything with their right hands unless they needed to apply force. They stood looking at me for a long time in amazement because, as far as is known, neither of the two ever created anything with their left hands.
As Da Montelupo delights in telling us, left-handed people do not produce mirror writing but handwriting like anyone else’s. The only difference is that they write with their left hands. Without training, mirror writing is as difficult for a left-hander to produce as it is for the average untrained right-hander. Should a child just beginning to write have an urge to start at the top right corner of the first page of his brand new exercise book, a simple cross next to the left margin to indicate the starting point is sufficient to set things straight.

Teachers are generally more concerned about reversed letters and words than about mirror writing. It’s a familiar phenomenon. When learning to write, children initially have a tendency to write certain letters backwards, especially capital S and capital N, along with the pairs d and b, and q and p. But this is not specifically something that applies to left-handers. Even adults unused to writing often run into trouble in this way, as do people daubing words in unusual circumstances – as slogans in giant letters on bridges and walls testify. Of course it may be that left-handed children have a stronger and more lasting tendency to reverse letters than right-handed children, but as yet no evidence for this has been produced. Until it is, we’re talking about nothing more than an impression, mainly in the minds of the right-handed majority. Generally speaking, such impressions have turned out to be less than reliable.

In reality it’s not at all difficult to write well and comfortably with the left hand. Or rather, no more difficult than with the right hand. There are just a few things you need to know.

Anyone writing with their right hand does best to hold the pen fairly loosely between the thumb and index finger, resting it on the side of the middle finger. The act of writing consists mainly of two kinds of movement, a slight flexing of the wrist, which gives the up and down lines in the letters, and a slow sweep outwards from the elbow that allows the line to be filled in steadily from left to right. Roughly speaking, that sweep begins straight in front of the centre of the body. The paper is at a slight angle, with the top right corner higher, so that the underarm lies perpendicular to the writing when it’s in the middle of the line. That way the writing hand remains under the line, where it doesn’t get in the way of the writer’s line of sight and minimal effort is required. If the wrist touches the page, it must not be leant on too hard if the script is to flow properly in its long sweep to the right.

Making upward lines thin and downward lines thick, as in calligraphy and elaborate, old-fashioned handwriting, is the logical way to stress how the letters are formed. On the downward stroke the wrist brings the hand towards the body, a movement that’s easier, firmer and more controlled than that which forms the upward lines, away from the body. Right-handed writing has much in common with the wrist movement involved in peeling potatoes.

Left-handed writing happens in almost exactly the same way. Again we ensure that the writing arm is perpendicular to the direction of writing when the hand is in the middle of the line. So again the paper naturally lies at an angle, this time with the top left corner upwards. The way the pen is held is the same too: loosely between thumb and forefinger, resting on the side of the middle finger. The pen must be held such that when the fingers are at rest the tip is only about a millimetre from the paper.

Now too the writing hand is always below the line, so there’s no need to smudge. The writer can easily see what he’s just written. The long sweep from the elbow is once again the means of getting from one end of the line to the other, except that now it’s a sweep not outwards but inwards, ending roughly in front of the centre of the body rather than starting there. So far, then, apart from the obvious reversal, everything proceeds in much the same way.

The really important difference in writing technique lies in the small movements that go to form the upstrokes and downstrokes. A right-hander uses an up and down motion of the wrist, whereas in a left-hander the direction of movement is at 90 degrees to this, roughly an extension of the hand and the pen. It involves simultaneously bending and stretching the thumb, forefinger and middle finger, which act in concert to direct the pen, a motion that closely resembles the removal of a splinter using tweezers.

Left-handed writing is a good deal more subtle and susceptible to changes in pressure than the potato peeling approach of right-handers. Inexperienced writers sometimes try to force their letters into shape by clutching the pen tightly and pressing it hard on the paper. This does nothing to improve even a right-hander’s writing, but in a left-hander it’s disastrous. A degree of attention and control is needed at the start, therefore, as well as a ban on the ballpoint, which only invites extra pressure. This will be more than enough to ensure a left-hander can write just as well as any right-hander. Even the ‘upwards thin, downwards thick’ comes naturally, since it emphasizes the inevitably light push to stretch upwards and the more powerful and confident pulling motion downwards.

It’s true that some letters will be formed in a different way by left-handers, who discover the best approach for themselves. They may well have difficulty with school workbooks that show them how to trace out the letters, since left-handers are always presented with the wrong model. Any teacher who isn’t too strict about how a left-handed pupil forms letters but concentrates instead on whether or not he’s producing functional, legible handwriting will be doing him and his kind a great service.

This is how good left-handed writing works. The paper is laid diagonally, so that the writing arm is parallel to the side of the paper and perpendicular to the line of text. The movement required to form the letters is not back and forth, as it is for right handers, but in and out, not unlike using tweezers to remove a splinter.

*
Da Montelupo probably means that he laid his paper crosswise and more or less wrote from top to bottom. It’s a rather extreme version of the diagonal position of the paper you often see with left-handers, which we’ll return to shortly.

37

The Myth of High Left-handed
Mortality

Perhaps the most disturbing message ever delivered to left-handers came in 1991. Deploying his considerable skill at attracting publicity, Canadian psychologist Stanley Coren made it known that left-handed people die no fewer than nine years earlier than right-handed people. At that time right-handers in the United States were living to be 75 on average, whereas left-handers gave up the ghost at only 66.5. He was the first person ever to have looked at left-handedness and detected such disastrous consequences.

Left-handers, familiar with all kinds of fantastic fables about their idiosyncrasy, let even this onslaught wash over them with a sense of resignation. Not so Coren’s fellow psychologists. Harsh criticism of the quality of the work of Coren and his faithful accomplice Diane Halpern soon appeared in professional journals, and even mainstream newspapers and magazines took note. The story nonetheless proved impossible to eradicate and it still pops up from time to time. There is therefore every reason to take another close look at why Coren’s story is wrong.

Coren had spent years studying left-handedness when it struck him that as well as being more common in men than in women it occurred more frequently in young people than in the elderly. To judge by the answers to questionnaires, left-handedness disappears over the course of a lifetime. Or could it be, Coren asked himself, that it’s the left-handers themselves who disappear? He decided to do some research.

First, in 1988, he carried out an exploratory study among American baseball players, the only group of people in the world whose hand preference is registered with painstaking precision. He concluded that left-handers die several months younger than comparable right-handers, a conclusion that researcher E. K. Wood of the California Institute of Technology demolished on technical grounds in
Nature
of 15 September 1988. As Wood convincingly showed, Coren had not done his statistical homework properly, so no conclusions at all could be drawn from his study.

Coren, however, continued undaunted along the path he’d decided to take. More extensive research was required, he decided. The main difficulty was to find data from a large number of more or less comparable dead people without shocking their families or coming up against overly scrupulous bureaucrats. Eventually, with the help of the local authorities, he succeeded in collecting the details of around a thousand people from a region of Southern California. He accumulated his data by asking families three things no sooner than nine months after a relative’s death: which hand did the deceased use to write, draw and throw a ball? If the answer to all three was the right hand, then the person in question was regarded as right-handed, otherwise the individual was recorded as having been left-handed.

Here already, right at the start, it’s clear that the research was seriously flawed. You may be able to say of a late member of your family which hand he or she wrote with, but are you equally certain about drawing? Even in the case of someone who wasn’t in the habit of taking out a sketchbook? How often have you actually seen your father or uncle draw? Do you have any idea which hand your mother or aunt uses to throw a ball? How long ago is it since you saw them do such a thing? If you think you know, are you completely certain? People can be fairly unreliable when researchers ask them questions about their own hand preference, so serious doubts must surely arise about how much faith we can reasonably have in this kind of information about family members, especially when they’ve been dead for at least the best part of a year.

Coren went on to compare the ages at which his left- and right-handed subjects died. That was how he reached the shocking conclusion that the lives of left-handers were nine years shorter on average, and that at all ages they ran a greater risk of dying than right-handers from the same geographical region.

Of course it’s true that even in the United States teachers used to treat left-handedness far more harshly than they do now, and that it was therefore the older members of the group Coren investigated who were most likely to have been intimidated and oppressed. Yet he was right to argue that this could not explain the enormous difference, since studies from the time when his subjects were young invariably showed that the percentage of people who openly stated they were left-handed was hardly any lower than it is now. Even in times of serious social rep ression, it seems people do not necessarily repudiate their left-handedness. Still, we need to be careful here. In those older studies people reported their own hand preference, whereas Coren’s study was about someone else’s. This is an important distinction.

Coren went looking for explanations for the astonishing outcome of his research, and he found them. In essence he believed that left-handed people had serious accidents far more often than right-handed people, sometimes with fatal results, and that long before they reached 70 a majority of them had died. He put this down to the fact that the world is arranged with right-handed people in mind, making it all the more dangerous that, or so he believed, left-handers are clumsier than their right-handed brothers and sisters.

One example of how he defended these conclusions is his study of car accidents. The psychologist claimed that left-handers cause more fatal crashes than right-handers do. He explained this by saying that left-handers have different reflexes. If someone is seriously startled, perhaps by having a ball thrown at his face, then a defensive reflex makes him put his hands up to protect himself, his favoured hand across his chest, in other words quite low down, and the other higher up, in front of his face. In a driver this same reflex, Coren claimed, meant that left-handers would tug the wheel to the left, into the oncoming traffic. Right-handers would tug it to the right, moving out of the traffic lane altogether.

It sounds credible, but in fact there’s not a single grain of truth here. First of all an essential part of the shock reflex is that the hands are spread wide, with the palms facing forwards. In a car this wouldn’t cause the horrified driver to tug at the wheel but to let go of it. If we don’t take our hands off the steering wheel in an emergency, then clearly that defensive reflex simply doesn’t occur, and there’s no good reason to think that one particular element of it would.

Still, let’s assume for a moment that Coren’s shocked reaction is of some relevance. In that case the situation in countries where people drive on the left must be dire, with all those right-handers causing head-on collisions. Sure enough, Coren declares without batting an eyelid that the traffic in those countries is pure pandemonium, and he takes Britain and Ireland as examples. There, he says, the roads are incredibly unsafe, with on average more accidents than in the rest of Europe. True, no one had ever noticed this before. In actual fact Coren was comparing apples with oranges. To prove himself right he set the figures for British and Irish traffic accidents against the average for fourteen other European countries as a whole. If we seperately compare each of the countries Coren looked at with Britain, and with each other, then Britain and Ireland come out as run-of-the-mill average. Indeed research by the European Union, carried out in the first decade of the twenty-first century, identified Britain as having the safest traffic of all the 27 countries of the
EU
, with Ireland in a respectable seventh place. Heading the danger list are our old friends Spain and France, where people drive on the right, as they do in most of the rest of the world.

Third, Coren bases his argument that left-handers drive much more riskily on the total number of fatal accidents in which one of his deceased research subjects was at the wheel. He doesn’t look at who was responsible. Worse still, he pays no attention to the nature of the crash, even though his reflex theory is relevant only to head-on collisions, which make up no more than a small proportion of the total number of accidents that result in fatalities.

Not only does Coren lump all road deaths together, the amount of data he draws upon is far too small. If we accept that American traffic is not hugely more dangerous than Dutch traffic, then based on the figures from the Dutch Central Bureau for Statistics relating to 1989, around 1 per cent of Coren’s deceased will have been victims of traffic accidents. So we’re talking about no more than ten or so fatalities, and those will include passengers, whose defensive reflexes are completely irrelevant. Still, let’s give Coren every possible benefit of the doubt and accept that among his victims of crashes all ten were responsible for the calamity that struck on their final journey. Coren proposes that left-handers are involved in fatal accidents four times as often as right-handers. Assuming that the average percentage of left-handers is the traditional ten, which fits reasonably well with Coren’s data, it turns out that Coren bases his sweeping conclusion on two or at most three accident-prone left-handers. In short, Stanley Coren is taking us for a ride.

One interesting and indeed fatal objection to Coren’s data in general was contributed by Dutch science journalist Martin van der Laan to the daily newspaper
Trouw
of 9 March 1991. He began with Coren’s claim that around 20 per cent of twenty-year-old men are left-handed but by the age of 50 this has declined to a mere 5 per cent. Coren claims the difference is explained by mortality rates. According to the Dutch Central Bureau for Statistics, around 5 per cent of all male citizens of the Netherlands die between the ages of twenty and 50. In other words, out of every 100 twenty-year-olds, an average of 95 reach the age of 50. The figures are no doubt comparable in the United States. This makes it simply impossible for the percentage of left-handers to have fallen from 20 to 5 between those same ages purely as a result of a high death rate. Even if only left-handers died, at least 15 per cent of people would be left-handed at 50. Anyone still in any doubt can rest assured; Coren fell into the trap of his own enthusiasm, drawing nonsensical conclusions based on demonstrably unrepresentative figures and an unsound method of processing them.

Yet it remains true to say that left-handedness seems to decline fairly steadily as the age of the group questioned rises. Coren’s basic error was to assume that this meant left-handers die young – a completely unfounded and far too drastic conclusion. If we ask groups of 50-year-old women whether they have recently become mothers, the answer will almost without exception be no, but we don’t go on to conclude that fertile women die young.

The other cause most commonly put forward is social repression. The simple fact that left-handedness used to be treated more harshly is taken to mean that large numbers of people eventually forgot they were really left-handed. This sounds improbable, and so it is. In large-scale research in Britain in 1998 it turned out that including or leaving out questions about socially loaded subjects such as writing, and to a lesser degree drawing, had hardly any effect on the degree to which left-handedness declined in frequency as the age of the subjects rose. In 2000 more than a thousand people aged 65 to 100 were questioned, and no connection with social pressure emerged. The researchers were forced to conclude that ‘age-related variations in hand preference can best be explained based on a number of factors of which the ways in which they influence each other is as yet poorly understood’. In other words: goodness only knows.

Yet ever since 1988 a far from implausible and fairly simple explanation for the fact that left-handers seem to dissolve into thin air has lurked within one of the studies Coren used to make his ill-considered bid for world fame. It’s a study set up and implemented by psychologists Ellis, Ellis and Marshall using far better methods than Coren’s and published in
cortex
, a journal of neuropsychology. It looked at more than 6,000 men aged between fifteen and 70. In this particular group of subjects, the percentage of left-handers fell from just over 9 per cent among the youngest to just over 5 per cent among the oldest. Although less dramatic than the mass annihilation that Coren claimed to have discovered, this difference is far too great to be attributed purely to a reduction in social pressure on left-handers. Like Coren, the researchers based their findings on questionnaires, but theirs were far more thorough than his primitive list of three skills. People were asked to indicate, by putting a cross in the appropriate column, whether they had a preference for one or the other hand when carrying out each of ten different tasks. If they had a strong preference, then subjects could indicate this by entering two crosses. Each participant therefore responded with a maximum of twenty crosses and a minimum of ten.

At this point we need to ask how far the way in which the youngest and oldest distributed their crosses needs to differ in order to produce the reduction in left-handedness that emerges. The answer is rather surprising: depending on how many double crosses were entered on average, only one in every two or three of the subjects who answered the questionnaire had to move, all told, one cross from left to right. In concrete terms this means that if out of every two or three people there’s one who in the course of a lifetime has switched hands for just one of the ten tasks, the difference is explained away entirely. In fact that person doesn’t even need to switch hands. It’s enough for him to have become less pronounced in his hand preference, so that instead of two crosses he enters one. Given the notion that we mellow with age, this is not at all improbable. Consider too the fact that the average fifteen-year-old is keen to be special and interesting. Left-handedness is out of the ordinary, so you’d be an odd kind of teenager if you didn’t milk it for all it was worth. Once you reach 40, such considerations have come to matter a good deal less.

Other books

Byzantium's Crown by Susan Shwartz
The Home for Wayward Clocks by Kathie Giorgio
Envious by Katie Keller-Nieman