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Neil Evans via Wikimedia Commons // Public Domain
Neil Evans via Wikimedia Commons // Public Domain

Fluency in Sign Language May Sharpen Peripheral Vision

Neil Evans via Wikimedia Commons // Public Domain
Neil Evans via Wikimedia Commons // Public Domain

A small new study found that people fluent in sign language had significantly better peripheral vision and reaction time than people who couldn’t sign. The research was published in the journal Frontiers in Psychology.

Researchers in the UK recruited 17 people who had been deaf since birth, eight hearing people fluent in British Sign Language (BSL), and 18 hearing people who didn’t sign at all. They brought everyone in to the laboratory and sat them down in front of computers to test their visual acuity, range, and reaction time.

Participants who had been signing from a young age fared far better than the other participants on visual tasks. “Deaf people have exceptional visual abilities that hearing adults do not,” lead author Charlotte Codina of the University of Sheffield said in a statement. “We found that deaf adults have faster reaction times around the whole of the visual field, extending as far as 85 degrees peripherally near the edge of vision.”

These results were unsurprising to Codina and her colleagues. The idea of sensory compensation—experiencing improvement in one sense when another is limited—is, by now, quite well established.

Less expected was that while deaf participants’ scores were the most impressive, they were followed by another group: hearing people who worked as BSL interpreters. These results suggest that fluency in sign language requires or builds visual processing skills that non-signers don’t have, and that adulthood is not too late to learn and benefit from the language.

BSL is not the only form of sign language used in the UK, but it is the most common. It includes a finger-spelled English alphabet, but is otherwise quite different from spoken English.

This was a small study, conducted on small groups of adults in a small country, but the researchers believe their results can be validated in future studies.

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Just 5 Alcoholic Drinks a Week Could Shorten Your Lifespan
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Wine lovers were elated when a scientific study last year suggested that drinking a glass of wine a day could help them live longer. Now a new study, published in The Lancet, finds that having more than 100 grams of alcohol a week (the amount in about five glasses of wine or pints of beer) could be detrimental to your health.

Researchers from the University of Cambridge and the British Heart Foundation studied the health data of nearly 600,000 drinkers in 19 countries and found that five to 10 alcoholic drinks a week (yes, red wine included) could shave six months off the life of a 40-year-old.

The penalty is even more severe for those who have 10 to 15 drinks a week (shortening a person’s life by one to two years), and those who imbibe more than 18 drinks a week could lose four to five years of their lives. In other words, your lifespan could be shortened by half an hour for every drink over the daily recommended limit, according to The Guardian, making it just as risky as smoking.

"The paper estimates a 40-year-old drinking four units a day above the guidelines [the equivalent of drinking three glasses of wine in a night] has roughly two years' lower life expectancy, which is around a 20th of their remaining life," David Spiegelhalter, a statistician at the University of Cambridge who was not involved with the study, tells The Guardian. "This works out at about an hour per day. So it's as if each unit above guidelines is taking, on average, about 15 minutes of life, about the same as a cigarette."

[h/t The Guardian]

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11 Things Contact Lens Wearers Should Never Do
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More than 30 million people in the U.S. wear contacts, but that doesn’t necessarily mean they take care of them quite as carefully as they’re supposed to. If you’ve worn contacts all your life and have never gotten an eye infection, you may think you’re a pro—but you’re probably putting your eyes at risk in at least one way, if not more.

Studies routinely find that eye patients don’t take care of their contact lenses exactly as they should, and may not even know they’re slacking. One 2011 study found that 85 percent of eye patients surveyed perceived themselves as compliant with the proper contact lens care practices, but in reality, only 0.4 percent were fully compliant. (The study was comprised of just 281 people, so that meant only one single person followed the proper procedures.)

There are plenty of ways you can put your eyes at risk when you wear contact lenses, some of which you might not even realize are dangerous. Here are 11 things you should never do with your contacts.

1. DON’T LET THEM COME INTO CONTACT WITH WATER …

The water in a swimming pool, a lake, the ocean, or even inside your home isn’t sterile, and that can mean bad news if that water gets under your contacts. People don't “really realize it could be a sight threatening move” to swim in contacts, optometrist Ceri Smith-Jaynes, a spokesperson for the UK-based Association of Optometrists who has been practicing for 20 years, tells Mental Floss. And it's not because they might float away: Soft contacts can change shape when wet, which can sometimes cause micro-abrasions on the cornea. And if that's not horrifying enough, there's an amoeba called Acanthamoeba that can live even in chlorinated water—and if it gets under your contacts, it can use the micro-abrasions to burrow inside your cornea, causing infection.

While rare, the infection is notoriously difficult to diagnose, and you can eventually lose your eye. (Smith-Jaynes just saw her first case of it in her professional career—the woman is expected to be fine, but had to spend weeks in the hospital putting in eyedrops every hour.) And even if you aren’t exposed to Acanthamoeba, there can still be other germs in water that contact lens solution can’t kill, so if you do break the rules and take a dive in your contacts, you should throw those lenses out immediately after. If you’re a passionate swimmer, you can always get prescription goggles.

Yes, your optometrist knows you probably go to the swimming pool and the beach in your contacts, despite their warnings. “I know my patients do it,” Smith-Jaynes says. “I’ve actually bumped into [a patient] and they recognized me—and they shouldn’t have, because I know how short-sighted they are.”

2. … SERIOUSLY, ANY WATER. OR ANY OTHER LIQUID, FOR THAT MATTER.

That means you should only touch your contact lenses if your hands are completely dry. In general, don’t let anything touch your contacts that doesn’t explicitly state it’s made for contact lenses. Saline solution won’t cut it, and neither will regular eye drops. Stick to solutions and drops that explicitly say “for contacts” on the bottle.

3. DON’T PUT THEM IN BEFORE YOU START YOUR MORNING ROUTINE …

As nice as it is to be able to read the shampoo bottle, you shouldn’t put your contacts in before you shower or wash your face, because—you guessed it—of the risk of exposing your lenses to tap water. You should also wait to put them in after you blow dry your hair or apply hairspray, because those can dry out your lenses.

4. … BUT DON'T WAIT UNTIL AFTER YOU APPLY MAKEUP.

You should put your contacts in before you put on your makeup, or risk damaging your lenses. If you have any makeup residue on your hands after you finish perfecting your eyeliner or contouring, and then you put in your contacts, you could get that on your lenses.

Avoid waterproof makeup, because if that gets on your contacts, the oils in it can’t be washed away by blinking. That could potentially cause your contacts to blur or damage the surface of the lens. Even if you wash your contacts with solution later, contact solution isn’t designed to clean up those types of oils, and it may not entirely remove them.

Wearing contacts may also inhibit certain looks, unfortunately. You shouldn’t apply mascara all the way from the base of your lashes up, since you are more likely to get makeup in your eye that way. Instead, apply it from the midway point. And you shouldn’t use eyeliner on the inner lid of your eye. Apply it to the skin above your lashes instead.

5. DON’T SLEEP IN THEM (UNLESS YOUR DOCTOR SAYS IT’S OK).

Sleeping in your contacts can lead to infection, too. Most contact-wearers know whether or not they’re allowed to sleep in their specific lenses, but you might not realize how risky wearing non-approved lenses to bed can be. “You’re greatly risking your sight” by sleeping in a lens that’s not approved for overnight use, Smith-Jaynes says. Because you don’t blink in your sleep, tears aren’t washing under your lenses, and your eye isn’t getting enough oxygen, both of which make it easier to get an infection. Sleeping in your contacts can lead to complications like corneal ulcers or a condition known as Contact Lens Induced Acute Red Eye (CLARE).

6. DON’T PUT YOUR DIRTY HANDS ON THEM.

You shouldn’t stick your dirty fingers in your eyes, period, but you definitely shouldn’t touch your contacts with them, for all of the usual reasons involving bacteria, oils, and other gross, damaging substances. You should always wash and dry your hands thoroughly before you touch your lenses.

7. DROPPED YOUR CONTACT? DON'T PUT IT IN YOUR MOUTH AND THEN BACK IN YOUR EYE.

Every once in a while, one of your contact lenses might come out in a public place, but you really shouldn’t root around on the floor trying to find it and put it straight back in—even if it means not being able to see for a while. If you do find the missing lens, don’t rinse it with tap water, and definitely don’t put it in your mouth. Ideally, you should just throw it away. To stay on the safe side, carry around an emergency pair of glasses or pair of disposable lenses in your bag or your car, or stash them in your desk at work.

“Most soft lenses are monthly or daily disposable so, if this unlikely event happens, you’re better off disposing of it and opening a new one,” Smith-Jaynes says. “It’s not worth trying to be thrifty here.” If you wear hard lenses and can’t throw them away immediately, inspect the dropped lens very carefully for scratches. If it looks like it made it through unscathed, you’ll want to disinfect it fully, including rubbing and rinsing it with solution and letting it soak overnight, before you think about putting it back in your eye.

8. DON’T WEAR A RIPPED LENS.

Besides being terribly uncomfortable, there’s a more serious reason to immediately toss a torn lens, even if it means being unable to see for the rest of the day. The jagged edge of the ripped lens can scratch your cornea. And because the lens won’t hold its regular shape, it won’t fit against your eye the same way, and is more likely to move around and possibly tear further, leaving you with bits of contact lens in your eye.

9. DON’T USE THE SAME CASE FOREVER.

You should be as careful with your lens case as you are with your contacts themselves. In order to minimize the bacteria and fungi that build up on the case, you need to rinse it out regularly with solution, then leave it open and upside down to dry fully. Whatever you do, don't rinse out your case with tap water—that has been linked to that nasty Acanthamoeba infection—and don't rinse out your case and then close it right back up without allowing it to dry—that creates a wet, dark environment for bacteria to grow (especially if you're using something other than solution). By the time you get back to it, it will be dirtier than it was before you rinsed it.

Even if you’re taking good care of your case, you need to toss it and get a new one regularly. If you change your lenses monthly, you should change cases then, too. After that, lens cases can start to develop a biofilm of bacteria and fungi, and if you store your contacts in there, you’re putting yourself at risk of infection.

10. DON’T WEAR THEM FOR TOO LONG.

Just because you can still see clearly out of your contact lenses doesn’t mean you should can keep using them for longer than you’re supposed to. If you wear your daily-use or weekly-use contacts for a month, it can, in the worst cases, lead to serious complications like scarring of the cornea and loss of vision. Daily disposable lenses, for instance, are made of a thinner material than contacts designed for longer use, and they're not made to allow the right amount of oxygen and moisture into your eye for an entire month. The few dollars you might save by not opening a new pack aren't worth the damage it can cause.

11. DON’T WEAR THEM WHEN SOMETHING IS WRONG.

If your eyes feel uncomfortable, don’t power through it; go see your doctor. If you notice any pain or redness in your eyes, take your contacts out and consult an optometrist. You don't want to let a serious infection go unchecked.

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