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Only 10-15% of all people are left-handed. The status of a minority sets a certain framework for perception: those who are somehow different from the main mass are perceived by others as inferior or, on the contrary, gifted. Then speculations begin: left-handers either try to retrain with all their might, or they expect outstanding successes and brilliant solutions from them. Meanwhile, today it is becoming more and more obvious that the connection between the brain and the dominant hand (leg, eye, ear) is not as straightforward as it seemed before. Research shows that many of our ideas about left-handers still need to be adjusted.

1. Left-handers are "programmed" not only by genes

There is no single answer to the question why some people become left-handed. It is known that genes are responsible for this feature in 25% of cases. Left-handedness is also inherited, but not as often as height or eye color. Even identical twins can sometimes have a different dominant hand. The choice in favor of left-handedness can be made by the brain in the womb. For example, one theory links this developmental scenario to exposure to high doses of the male hormone testosterone. In addition, severe maternal stress during pregnancy can cause oxygen starvation (hypoxia), which leads to oppression of the more sensitive left hemisphere.

2. Left-handers are not necessarily "right-brained" people

The right and left hemispheres not only control “their” (opposite) side of the body, but also determine how we process information, solve problems, and respond to stimuli in different ways. It used to be that most right-handed people use the left hemisphere of the brain for speech-related tasks, while left-handed people have their language center located in the right hemisphere. But further research did not reveal a clear trend: linguistic left hemisphere was observed in 88% of right-handers and 78% of left-handers. Pronounced right hemispheric language activity was only in 7% of left-handers 1 . "Most left-handed people use the same areas for language as right-handers," says Gina Grimshaw, a neuroscientist at the University of Wellington, New Zealand. - As for such functions as attention, emotions, perception, we do not have data to make generalizations. But left-handers definitely don't have the "flipped" brain that some people think."

3. Left-handedness is not a sign of creative thinking and high intelligence

You can often hear that left-handedness comes "complete" with outstanding abilities. But, according to Ronald Yeo, professor of psychology at the University of Texas, there is no serious evidence for this. This rumor was born in 1995 when one study found that left-handed men find more varied and unusual ways to solve problems. “There is a reasonable grain in this idea, but still it cannot be said that discoveries and breakthroughs in science or art should certainly be expected from a left-hander,” says Ronald Yeoh. Neuroscientist Tatyana Akhutina agrees with him. "A neuropsychological study of gifted schoolchildren with high achievements in mathematics showed that among them there are both pronounced right-handers and left-handers and ambidexters."

4. Lefties are probably more emotionally sensitive.

Psychologist Zhanna Lukyanchikova and her colleagues found that among gifted adolescents, left-handers and ambidexters (especially those with different preferences for the eye and ear) often have an increased level of anxiety, introversion, and asthenia, while right-handers more often showed strong-willed qualities and perseverance in solving problems. In addition, in a study by psychologists at the University of Abertey (UK), left-handers more often agreed with statements like “I often worry about my mistakes”, “criticism hurts me a lot” 2 . At the same time, data obtained on a larger sample did not reveal significant differences in the temperament of right-handers and left-handers. Perhaps the anxiety of left-handers manifests itself precisely in stressful situations, when their abilities will be evaluated by others. One way or another, this question is not yet completely clear.

5. Lefties really see the world differently.

In many languages, "right" also means "true", "fair", "truthful". Left-handers are characterized by the opposite attitude: what is on the left causes them more trust and sympathy. “A person with a dominant left side of the body (hand, eye, ear) will intuitively prefer those objects and images that are on the left, even if he cannot justify this,” explains Ronald Yeo. - This effect can be observed in various life situations when you need to make a choice. For example, during voting in elections, when the names of candidates are placed on the left and right on the page, a left-hander is more likely to choose a left-hander (if he is not familiar with them and their program).”

6. Left-handedness does not affect overall health

There has long been concern that left-handedness has something to do with impaired immune function and that it could be a risk factor for autoimmune disorders. Neurologist Norman Geschwind believed that exposure to testosterone in the womb delayed the process of neuronal localization. In his opinion, this delay not only causes left-handedness, but also slows down the development of the immune system. Most of these suspicions were not confirmed, and Gershwind's theory as a whole was refuted. However, some diseases, such as Crohn's disease and ulcerative colitis, are indeed more common in left-handers than in right-handers.

1 PLoS One, 2012, vol. 7, no. 4.

2 See abertay.ac.uk for more details.

90% of the population is made up of people whose dominant hand is the right. However, there is still a certain percentage of left-handers. In most physiological and psychological features, they are the same people as the rest. However, it is widely accepted by scientists that the brain of left-handed people works a little differently than that of right-handed people.

According to Ronald Yeoh, professor of psychology at the University of Texas at Austin, the governing hand is determined in the womb, since it is during this period that the basic mechanisms of the body are formed in the child. To find out why people who write with their left hand are so special, the list of facts listed below will help you.

Genes are not always to blame

Oddly enough, heredity is responsible for the birth of a left-handed family in only 25%. Much more often, children copy character traits, physiological characteristics, and even the level of intelligence from their parents. It has been observed that if two identical twins develop in the womb, they may well be born with different dominant hands. Although in all other respects the kids will be similar to each other.

It all depends on the course of the pregnancy.

Once upon a time, British scientists conducted an experiment, as a result of which it was found out that which hand the child will be dominant depends on the emotional state of the expectant mother. According to statistics, most left-handers are born to women who were psychologically depressed or experienced severe stress during pregnancy. In addition, the chances of asymmetric hand dominance increase with childbirth in old age, as well as in babies with a large body weight.

Interestingly, the researchers also found that this phenomenon also depends on the environment. So, if the faces of the expectant mother are more often touched with the left hand, then it is likely that the baby will not be right-handed.

It is more common in twins

Speaking of twins: they are far from rare cases when one child turns out to be left-handed. Scientists have repeatedly proven that twins often turn out to be not just copies of each other, but a mirror image. For example, if one of the children has a mole on his face, then the other will most likely have the same, only on the opposite side.

Of all twins born in the world, about 21% end up with different dominant hands. Left hemisphere dominant individuals are twice as common in twins than in the general population.

Noticeable advantage in sports

If you play tennis, boxing, or anything else where arm movement plays an important role, you can be sure that this feature will be an advantage. So, most athletes work out the technique, adapting to the partner. If one of the opponents turns out to be left-handed, then this will put the second into a stupor. Asymmetry will confuse the athlete, as it will be difficult for him to predict the actions of the opponent.

By the way, some lefties are almost perfect with both hands. In this case, they can become real champions in sports, constantly changing the tactics of their movements during the competition.

Not an ounce more creativity

Since the end of the last century, there has been a rumor that left-handers have innate inclinations for non-standard thinking. In other words, society says that people with a non-standard dominant hand are more inclined towards creativity than right-handed people. Modern research completely refutes this theory and proves that it is nothing more than a myth. Scientists have found that creativity is inherent in every person and depends only on the ability and desire to develop it. So without enthusiasm it is impossible to form creative thinking in yourself, and it doesn’t matter whether you are left-handed or right-handed.

Risk of developing mental disorders

If everything is in order with the physiology of left-handers, then their emotional state may be slightly unbalanced. Such people are much more likely to be diagnosed with manifestations of dyslexia, inattention, hyperactivity, and even depressive disorders. The following can also be added to the unpleasant moments: about 40% of patients with schizophrenia are left-handed. Of course, the situation is not inspiring, but all these are statistics derived by experts in the field of medicine.

Possible decline in school performance

In 2009, a study was conducted among children under 11 years of age. During it, it was found that babies who operate with their left hand are less amenable to the educational process than right-handers. They showed poor performance in reading and working with dictionaries, as well as in writing. Particular problems arise in children who equally control both the right and left hands. This forces them to choose.

At the same time, it is worth noting that the left hemisphere functions just as well. It's just that a child, as a rule, needs to get used to learning. If the kid tries, then after a few years he catches up with his classmates in academic performance and can even get ahead of them.

Are left-handed people prone to alcoholism?

In fact, this is nothing more than another "duck". Two versions of this myth roam among the people. The first seems more plausible: Left-handers tend to crave alcohol because they use both hemispheres of the brain. Although this opinion is completely not substantiated by any facts. The second version is more of a joke. It says that left-handed people want to drink because they are not like everyone else. Naturally, none of the proposed options is true.

Well, in fact, it's not so important - a left-handed person or a right-handed person. The main thing is that he feels comfortable and confident.

Finally, society can also influence the phenomenon of right- or left-handedness. In Soviet times, for example, it was believed that left-handed children should be retrained. Therefore, if the parents saw that the child was holding a spoon or a pencil with his left hand, they forbade him to do so and insisted that he use his right hand. Kindergarten teachers and school teachers did the same. Therefore, in principle, there may be more congenital left-handers than we think.
What is the difference between lefties and righties?
It is known that many prominent personalities - politicians, scientists, actors, artists, composers - were left-handed. Among them - Isaac Newton, Albert Einstein, Julius Caesar, Alexander the Great, Napoleon Bonaparte, Winston Churchill, Bill Clinton, Leonardo da Vinci, Pablo Picasso, Andersen, Mozart, Aristotle, Nietzsche, Charlie Chaplin ... But does this mean that all left-handers – potential geniuses?
Ohio psychologists Stephen Christman and Ruth Propper conducted a curious experiment to test memory. They selected 62 people and asked them to memorize 55 words that flashed on the screen. Left-handers coped with the task two (!) times better than the rest. According to scientists, this is due to a closer interaction between the hemispheres of the brain. However, the memory of lefties is selective. So, it is easier for them to remember where they put some thing than to reproduce by heart a culinary recipe or a historical date.
Over the past three decades, the number of left-handed people in the world has increased markedly. According to Swedish researchers, this is due to the fact that the ultrasound procedure, which expectant mothers undergo during pregnancy, affects the brain and central nervous system of unborn children. According to some reports, there are now more than 800 million left-handers in the world, and by 2020 their number will exceed one billion ...
Finally - a test for hidden "left-handedness", recommended by psychologists. Cross the fingers of both hands together. If the thumb of your left hand is on top, you are left-handed from birth.

How do we remember?

No one can explain how the brain remembers information and how we then reproduce it. But we know quite a lot about the different types of memory and the methods that help us do it.

Memory is the ability to keep in mind everything we have learned and experienced. Everything that happens to a person is deposited on a kind of memory track. This record is not erased for a long time if it is constantly used or repeated.

There are several ways to remember. The first is remembrance. For example, if a few days after a party someone asks you who took part in it, you will try to remember their names and appearance.

Recall is different from recognition, another type of information storage. If you are asked if Bill Jones was at the party, then you may recognize this name as the name of one of those who were there. Or, meeting him on the street, you will recognize him as the person who was with you at the party.

Remembering is harder than knowing. If the teacher asks you to remember what was said in class last week, it will be harder to answer than if she named the subject and asked if it was already said.

There is visual memory. So, you may remember last summer vacation as a picture of a cabin in the mountains before your eyes. In the same way, you can hear music after the tape recorder is already turned off. This is called auditory memory.

Another type is associative memorization. When you experience something, it is usually accompanied by some other impression. Binding or association occurs, and when you remember one of the events, another one pops up in memory.

Many parents of left-handed children are very worried about this, but are even more surprised when they are told that they should not try to fix it. The authorities say that if there is a strong advantage of the left hand and one easily controls it, then this should not be hindered.

About 4% of the population are left-handed. If you look into history, it turns out that many geniuses were left-handed, for example, the greatest sculptors of all time - Leonardo da Vinci and Michelangelo.

Of course, we live in a right-handed society, and most of the items we use are made for such people. Doorknobs, locks, screwdrivers, cars, musical instruments and even buttons on clothes. Everything leads to the appearance of certain adaptations for left-handers, but often they do well without it.

There is no generally accepted explanation for why most people are right-handed, and only a small number are left-handed. One theory is that our body is asymmetrical, that is, the right half does not exactly repeat the left. The right side of the face is slightly different from the left, one leg is longer than the other, the feet are slightly different in size. And this asymmetry is observed throughout our body.

The right and left hemispheres of our brain also function differently, and it is assumed that the left dominates over the right.

Nerves connect each hemisphere to the opposite side of the body: the right hemisphere to the left and vice versa.

And since the left side of the brain predominates, then the right side of the body is more perfect, better adapted. We read, write, speak and work with the left hemisphere of the brain. This explains the fact that most of us are right-handed. In left-handed people, a rearrangement occurs, that is, the right side of the brain prevails over the left, and therefore, such people have a better command of the left side of the body.