Napoleon and Julius Caesar had more in common than their leadership. Also Alexander, with Hugo Chavez and four of the last seven U.S. presidents. All of them are lefties. Are people who drive with my left hand better able to govern? What are the differences in the brains of right and left handed? Science is showing a recent interest in these issues but for now, the answers are not clear.
"It is unclear why a person is left or right handed", recognizes ELMUNDO.es Roberto Gallego, Institute of Neurosciences of Alicante, which is part of the CSIC, "although it does seem that" the preference for a hand or the other begins to develop in the fetus. " Theories suggest that the hand that baby is always closer to the mouth is the most used in your life.
Some data confirmed on lefties. For example, the percentage of left-handed people in the world is held constant at 10%. "Even if you are not sure how some of today are left-handed corrected, "he admits Gallego, recalling that not so long ago" these people were forced, with all sorts of methods, using the other hand. "
Throughout history outrages have been several low the false belief that they were possessed by the devil, they were more likely to commit crimes and a lot of myths. So we had to "reeducate" the kids 'deviant'. It happened to Daniel, now 33 years and continues to be handed to all, but at school who tied her left hand to write with his right. "A force learn, of course, but once the class had just returned to using his left hand, because it is what comes naturally, "he says. In fact, research published recently in the journal Cortex ', conducted by a team from the University of Ontario (Canada), refers to" right-handers are more skilled than left-handed. "In other words," people who regularly use the left have much more dexterity with the right hand with the opposite right-handers. Possibly because since childhood they have been forced to use both hands, "said David P. Carey, one of the authors.
less long-lived
Another documented in the scientific literature is that left-handers are less long-lived. There are several hypotheses the point, as Roberto Gallego. "One of them indicates a possible impairment may occur during development that left-handers do more prone to disease, but it is unclear the issue."
In 2007, a team of researchers from the University of Oxford discovered a genetic variant associated with a predilection for the left hand LRRTM1. This gene is also characteristic of people with schizophrenia, as was initially thought that left-handers could have higher risk of disease. However, a job last year found no link between the two. As explained by the authors themselves in The New York Times, "schizophrenia is a complex and heterogeneous disorder and it is unclear what role this gene plays exactly, but we have seen that it can establish a relationship between left-handedness and schizophrenia"
Brain cross
brain differences between left and right handed even more confused. The brain has a right and one left hemisphere and each is responsible for very different functions. Thus, the left side is responsible for processing information and digital logic while the right is more focused on emotions and feelings. But what about writing? As in most people are controlled from the left side, but about 15% of left-handers have speech centers in both hemispheres.
"As a rule the left frontal cortex controls the right hand and vice versa. The projections are crossed. But it seems that lefties are more distributed functions between the two sides, though the impact this can have is not very clear" says Robert Gallo. Although this expert believes that many world leaders are left-handed "is a coincidence", it says the same in the case of athletes. "What is left-handed Nadal and world number one tennis is no accident because, in sport, a southpaw has much easier to trick a clever than the reverse. "
However, to date there are more legends than certainties about lefties.
http://www.elmundo.es/elmundosalud/2011/ 03/25/neurociencia/1301074769.html
0 comments:
Post a Comment