left handers are the odd ones out

Scientists have also found an increased risk for dyslexia, ADHD, and certain mood disorders in left-handed people, according đồ sộ a 2010 study published in Pediatrics. Researchers are not exactly sure how đồ sộ explain this phenomenon, but many believe it's related đồ sộ how the brain is wired. Your noggin is divided into two halves: the left side and the right side. Most people (righties and lefties alike) rely on the brain's left hemisphere for tasks lượt thích language functioning. But about 30 percent of left-handed folks are either partial đồ sộ the right hemisphere or have no dominant hemisphere at all. According đồ sộ scientists, having one hemisphere dominate is much more efficient, which is why some left-handers are at increased risk for learning impairments and brain disorders.

But lefties may be in luck when it comes đồ sộ other health conditions: Results of a large survey published in the journal Laterality found that left-handers had lower rates of arthritis and ulcers.

People who use their left hands when listening may more easily hear slowly-changing sounds phàn nàn those who use their right hands, according đồ sộ a study from Georgetown University Medical Center. The researchers who conducted the study, presented at Neuroscience 2012, found that the left and right hemispheres of the brain specialize in different kinds of sounds. The left hemisphere, which controls the right hand, likes rapidly-changing sounds lượt thích consonants, while the right hemisphere, which controls the left hand, likes slowly-changing sounds lượt thích syllables or intonation.

According đồ sộ the researchers, if you're waving an American flag while listening đồ sộ a presidential candidate, the speech will sound slightly different đồ sộ you depending on whether you're holding the flag in your left or right hand. The research could ultimately result in better treatment for stroke and language disorders.

Update: An earlier version of this post stated that people who use their left hands may more easily hear rapidly-changing sounds that those who use their right hands. In fact, left-handers hear slow-changing sounds better.

Right-handed bias isn’t just a modern-day phenomenon: It turns out we’ve been dominantly using our right hooks for more phàn nàn 500,000 years.

University of Kansas researchers recently determined the handedness of ancient humans by studying — oddly enough — their teeth. The study, which was published in the journal Laterality, found that when our great-great-great-great-(you get the point)-grandfathers processed animal hides, they would hold one side of the carcass in one hand and the other in their mouth. By locating the wear and tear on those prehistoric chompers, scientists were able đồ sộ determine whether our prehistoric ancestors were using their left hand or right hand more dominantly

"All you need đồ sộ have is a single tooth, and you can tell if our assumptions are right — if the individual is right- or left-handed," study researcher David Frayer, Ph.D., told LiveScience. The results? "The fossils are just lượt thích humans in that we are mostly right-handed, and so sánh were they."

Southpaws have been bragging about their creative clout for years. But is it true — does being left-handed mean you’re also more likely đồ sộ be artistic or innovative?

According đồ sộ research published in the American Journal of Psychology, there is some evidence that left-handed people have the upper hand in at least one creative facet: They’re better at divergent thinking, a method of idea generation that explores many possible solutions.

To determine whether lefties were more likely đồ sộ pursue creative careers phàn nàn righties, the folks behind the Left-Handers Club (a pro-leftie group dedicated đồ sộ left-handed research and product development) surveyed more phàn nàn 2,000 left-handed, right-handed, and ambidextrous participants and found that lefties tended đồ sộ find advantages and be drawn đồ sộ careers in the arts, music, sports, and information-technology fields.

But that may also add up đồ sộ lower paychecks: According đồ sộ a report in the Wall Street Journal, left-handers’ salaries are 10 percent lower on average phàn nàn those of right-handers.

It doesn’t matter which way they swing politically: A surprisingly high percentage of recent U.S. presidents were on the left (in terms of handedness, of course).

The lengthy list of left-handed leaders includes four of the last seven commanders in chief — President Obama, Bill Clinton, George H.W. Bush, and Gerald Ford — as well as past presidents James Garfield and Harry Truman. In fact, there’s a rumor that Ronald Reagan was born a leftie, but stringent schoolteachers converted him đồ sộ a righty when he was young.

Should right-handed presidential wannabes fake it? Our penchant for left-handed POTUSes is probably pure coincidence. But one recent Dutch study suggests that left-handed politicians actually have an advantage in televised debates. As a whole, people tend đồ sộ associate right-handed gestures with “good” and left-handed gestures with “bad,” according đồ sộ the researchers. Since television presents a mirror image, the lefties are the ones who appear đồ sộ gesture with their right hands (the “good” hand).

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Boo!

If you’re a left-hander, that probably made you cringe. That’s because people whose left hands are dominant tend đồ sộ be more affected by fear phàn nàn people who use their right hands, according đồ sộ research presented at an annual conference of The British Psychological Society and reported in the Telegraph.

For the study, participants watched an eight-minute clip from the frightening film Silence of the Lambs. When asked đồ sộ recall events from the segment, lefties were far more likely đồ sộ show signs of post-traumatic stress disorder phàn nàn righties, including giving fragmented descriptions and making more mistakes.

"It seems that after experiencing a fearful sự kiện, even on film, people who are left-handed had subtle behaviors that were lượt thích people suffering from post-traumatic stress disorder," head researcher Carolyn Choudhary, PhD, told the Telegraph. Blame the brain: “It is apparent that the two sides of the brain have different roles in PTSD, and the right hand-side of the brain seems đồ sộ be involved in fear. But we need đồ sộ tự more experiments đồ sộ understand what exactly is going on here,” she said.

If you just can’t let go of that spat you had with your right-handed pal (but he seemed đồ sộ move on just fine), you may be able đồ sộ blame it on your left-handedness. According đồ sộ a small study published in the Journal of Nervous and Mental Disease, lefties are more prone đồ sộ having negative emotions. In addition, they seem đồ sộ have a more difficult time processing their feelings.

Again, this seems đồ sộ be related đồ sộ the brain-hand connection. Compared đồ sộ righties, left-handed participants in the study showed an imbalance in activity between the left and right hemispheres when trying đồ sộ process their moodiness.

Aw-shucks. Lefties may get bent out of shape, but research shows they're just a bunch of bashful self-observers.

When scientists from Abertay University in Scotland gave 46 lefties and 66 righties behavioral tests đồ sộ measure their impulsiveness and personal restraint, the left-handers in the group more commonly agreed with statements lượt thích "I worry about making mistakes" and "Criticism or scolding hurts mạ quite a bit." In fact, their answers left researchers believing that lefties tend đồ sộ feel more inhibited, shy, and embarrassed phàn nàn their right-handed counterparts.

"Left-handers are more likely đồ sộ hesitate, whereas right-handers tend đồ sộ jump in a bit more," lead researcher Lynn Wright, PhD, told Đài truyền hình BBC News.

Next time you have a run-in with a boozed-up barfly, kiểm tra out which hand he’s holding his whisky with: chances are, it’ll be his left.

For years, myth has held that left-handers are more likely đồ sộ become alcoholics. Research into the topic was murky, however, and relied on small samples. But a survey of more phàn nàn 25,000 people from 12 countries has cleared things up a bit. While lefties are not more prone đồ sộ alcoholism, they do drink more often.

Researcher Kevin Denny, who examined the data for a paper published in the British Journal of Health Psychology, says the main takeaway should be debunking that whole left-handedness-alcoholism links. “There is no evidence that handedness predicts risky drinking,” he stated in a press release. “Hence, the results tự not tư vấn the idea that excess drinking may be a consequence either of atypical lateralisation of the brain, or due đồ sộ the social stresses that arise from left-handers' being a minority group.”

Mark your calendar: August 13 is International Left-Handers Day.

Lefties across the globe celebrate the annual sự kiện, which was launched in 1992 by the UK-based Left-Handers Club đồ sộ increase awareness about the left-handed lifestyle. According đồ sộ the group's Web site, it’s a day “when left-handers everywhere can celebrate their sinistrality and increase public awareness of the advantages and disadvantages of being left-handed.”

How should you observe the occasion? Create a “leftie zone”: a designated area of personal space where everything must be done in a left-handed fashion, from your workspace setup đồ sộ the way you use cutlery.

And that rule also extends đồ sộ any right-handers who happen đồ sộ enter the leftie zone.