Kim J, Matthews NL, Park S via Wikimedia Commons // CC BY 2.5
Kim J, Matthews NL, Park S via Wikimedia Commons // CC BY 2.5

Software Flaws May Invalidate 40,000 Neuroscience Studies

Kim J, Matthews NL, Park S via Wikimedia Commons // CC BY 2.5
Kim J, Matthews NL, Park S via Wikimedia Commons // CC BY 2.5

The human fallibility of science has been in the news a lot lately. The latest hit? Researchers say the three most popular programs for interpreting functional magnetic resonance imaging (fMRI) results all produced shockingly high rates of false positives—a finding that could invalidate tens of thousands of studies. The report by researchers from Sweden's Linköping University and the UK's University of Warwick was published in the Proceedings of the National Academy of Sciences.

Over the last two and a half decades, fMRI has become a crucial tool for investigating the brain and its inner workings. Because our bodies supply blood to the parts that need it most, fMRI’s ability to measure blood flow in the brain allows us to track brain activity. But just how good of a job is it doing? Scientists weren’t really sure.

“Functional MRI (fMRI) is 25 years old, yet surprisingly its most common statistical methods have not been validated using real data,” the authors write. 

To test it, they pulled data on 499 healthy people from the 1000 Functional Connectomes Project, a database of baseline brain scans. They then split their subjects into different subgroups and compared the scans in different permutations, over and over, until they had 2,880,000 different group analyses.

For a long time, neuroscientists have believed that scanning the brain of a healthy person in a resting state should yield no signs of activity. Consequently, any sign of activity could be read as a positive result.

But the authors of the current study say that assumption could be wrong, and following it could lead to a lot of false positives.

Looking at the results of their almost 3 million comparisons, the researchers expected to find a false positive rate of about 5 percent. Instead, they found that the top three fMRI analysis programs—Statistical Parametric Mapping, the fMRIB Software Library, and Analysis of Functional Neuroimages—yielded false positive rates up to 70 percent. That’s right: seven out of 10 scans analyzed using these methods came to inaccurate conclusions. And the authors say that may be a conservative estimate.

If these findings are correct, it has a huge impact on neuroscience research. In a literature search, the authors found more than 40,000 neuroscience studies that relied on fMRI results. Still, there may be no point in going back and re-doing these studies. It’s better to look to the future, the authors say: "Considering it is now possible to evaluate common statistical methods using real fMRI data, the fMRI community should, in our opinion, focus on validation of existing methods.”

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Citroën
These Funky Glasses Are Designed to Reduce Motion Sickness
Citroën
Citroën

There's nothing like a sudden wave of nausea to ruin a scenic road trip or a cruise. According to Visuall, the French car company Citroën has made a product that allows you to fight motion sickness without medication.

Their glass-less spectacles, called SEETROËN, implement technology first developed by the French startup Boarding Ring. Motion sickness occurs when the information we receive from our inner ear doesn't match up with what we see in front of us. SEETROËN tackles this problem in a simple way: Liquid at the bottom of all four rings (two in front of the eyes, two at the peripheries) responds to gravity and changes in movement the same way the fluid in your inner ear does. By having an "artificial horizon" to look at when you're in the back of a bumpy car, your visual senses should realign with your sense of balance, and you'll no longer feel queasy.

The accessory isn't exactly fashionable, unless maybe you're going for a space-age look, but you shouldn't worry about appearing goofy for too long. After staring at a still object like a book through the glasses for 10 to 12 minutes, you can remove them and continue to enjoy the benefits as you proceed with your trip, the company claims.

SEETROËN is currently out of stock at Citroën's lifestyle store, with the next shipment estimated for September. The company claims the spectacles show positive results 95 percent of the time, and the technology it uses won an INNOV'inMed award for health innovation. But like with any new technology meant to treat a medical condition, users should be cautious. Time-tested ways to prevent motion sickness include sitting in the front seat of a car, eating something light before you travel, and focusing your gaze on something outside the nearest window.

[h/t Visuall]

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iStock
5 Simple and Painless Ways to Remove a Splinter
iStock
iStock

Splinters are as sneaky as they are annoying. You never see one coming, but once one gets embedded in you, you’re definitely going to feel it. The most common way to pull one of these out of your body is to grab a pair of tweezers and just start digging. While that might work for splinters that haven't lodged too deep into your body, it’s far from ideal for the ones completely under the surface. Plus, it hurts.

Thankfully, you don’t always need sharp instruments or a trip to the doctor to get rid of those stubborn splinters—there are plenty of items lying around your house right now that can help draw them out. So the next time you find yourself with a painful piece of wood or other material stuck in your foot, finger, etc. be sure to wash the affected area with soap and warm water and give one of these simple—and painless—remedies a try.

1. SOAK IT IN EPSOM SALTS.

Epsom salts are an incredibly versatile cure-all for common ailments like sunburn and sore muscles. But one of its lesser known uses is the fact that it can help bring deep splinters to the surface of your skin.

To get this to work, just dissolve a cup of the salts into a warm bath and soak whatever part of the body has the splinter. Failing that, you can also put some of the salts onto a bandage pad and leave it covered for a day; this will eventually help bring the splinter to the surface. Both methods help to draw the splinter out, which you can then pull out completely with a tweezer.

2. SLAP A BANANA PEEL ON TOP OF IT.

They can do everything from whiten your teeth to shine your shoes, but banana peels can also rid you of your splinter woes. Simply take a portion of a ripe peel and tape the inside portion over the area with the splinter. From there, the enzymes in the peel will get to work by softening your skin and helping the splinter move closer to the surface.

Some say just a few minutes is often all it takes, but if you can leave it on longer (especially overnight), you’ll have a better chance that the splinter will surface. Sometimes it will be drawn out far enough that it will come out on its own when you remove the peel; other times you may still need to use a pair of tweezers to finish the job. And if it doesn’t work after one night, replace the peel and leave it on for another day.

Don’t have a banana handy? You can also try a potato slice using essentially the same method: Place the skinless side on the area, hold in place with a bandage, and leave it on overnight. Then remove it and see if the splinter has surfaced.

3. MAKE A BAKING SODA PASTE.

First, before you do anything, clean the affected area with soap and water. Then combine a little water with ¼ of a tablespoon of baking soda to make a paste that you can then spread on the splinter. Once the paste is spread, cover the area with a bandage and keep it just like that for a full 24 hours.

You should notice that the splinter has made its way to the surface, where you can now simply just remove it. If you still can't get a hold of it, you can repeat the same procedure until the splinter is sufficiently brought above the skin.

4. USE SOME TAPE.

This method is best when a splinter is already drawn to the surface a bit but tweezers just won’t do. Simply take a piece of tape—go for something a little stronger, like duct tape—and place it over the splinter. Once the tape is secure (leave it on for a few minutes), gently pull it off. You may have to repeat this a few times to coax the splinter out. For a little added security, soak the area in warm water first to soften the skin.

5. VINEGAR OR OIL.

Another simple way to draw out that stubborn splinter is to soak the affected area in oil (olive or corn) or white vinegar. Just pour some in a bowl and soak the area for around 20 to 30 minutes, then eyeball the splinter and see where it is. If it looks closer to the surface, but not enough to pull out, soak it longer. Once it gets far enough out, just remove it and wash the area with soap and water.

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