Blame the Brain for the Hearing Loss That Comes With Aging

iStock
iStock

The reason why older people typically can’t hear very well has very little to do with the functional capabilities of their ears, Co.Exist reports. Instead, as a recent study in the Journal of Neurophysiology (freely available here) investigates, it has more to do with how the brain processes sound, and how that ability deteriorates as we age.

Researchers at the University of Maryland, College Park report that the deterioration is due to aging’s effect on the brain’s midbrain (associated with hearing as well as vision and motor control) and cortex (associated with thought and language). The study examined 17 younger adults and 15 older people with no signs of dementia. They were asked to listen to an audiobook while another narrated audiobook played in the background.

When trying to distinguish between the voices of two different speakers, the midbrains of older adults don't respond as strongly as those of younger people. The older adults' brains couldn’t encode the auditory signals as well, and they took longer to process speech, especially when there were two competing voices. The older brain appears to be less capable of picking out one sound out of many.

However, their cortex actually reconstructed the amplitude of the speech they heard in the brain with greater accuracy—an exaggerated response, which may reveal why older people need to pay more attention to process the noise of people talking. As the study's abstract notes, this response suggests "an age-related over (or inefficient) use of cognitive resources that may explain their difficulty in processing speech targets while trying to ignore interfering noise."

So the next time you encounter an older individual who is hard of hearing, don’t bother trying to speak louder. It won’t help them hear you any better. Instead, move your conversation to a place with less background noise.

[h/t Co.Exist]
 
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5 Holiday Foods That Are Dangerous to Pets

iStock/svetikd
iStock/svetikd

One of the best parts of the holiday season is the menu of indulgent food and drinks that comes along with it. But while you enjoy that cup of spiked hot cocoa, you’ve got to be careful your dog or cat doesn’t nab a lick. Here are five holiday treats that are dangerous for your pets, according to Vetstreet.

1. COFFEE

Any coffee lover will agree that there’s nothing quite like an after-dinner cup of joe on a cold night. But pups, kitties, and other pets will have to sit this tradition out. Caffeine can prompt seizures and abnormal heart rhythms in pets, and can sometimes be fatal. Other caffeinated drinks, such as soda or tea, should also be kept away from your four-legged family members.

2. BREAD DOUGH

We know the threat that bread dough poses to the appearance of our thighs, but it’s much more dangerous to our furry little friends. Holiday bakers have to be careful of unbaked bread dough as it can expand in animal stomachs if ingested. In some dogs, the stomach can twist and cut off the blood supply, in which case the pup would need emergency surgery.

3. CHOCOLATE

Cat and dog in Santa hats chowing down on plates of food
iStock/TatyanaGl

A little chocolate never hurt anybody, right? Wrong. The sweet treat can cause seizures and even be fatal to our pets. Darker chocolate, such as the baker’s chocolate we love to put in our holiday cookies, is more toxic to our pets than milk or white chocolate. The toxic ingredients include caffeine and theobromine, a chemical found in the cacao plant.

4. MACADAMIA NUTS

Macadamia nuts, which are a common ingredient in holiday cookies and often put out to munch on as an appetizer, can be toxic to dogs. While poisoning might not always be easy to detect in a pet, clinical warning signs include depression, weakness, vomiting, tremors, joint stiffness, and lack of coordination.

5. ALCOHOL

Think back to when you first started drinking and how much less alcohol it took to get you tipsy, because you likely weighed less than you do now. Well, your pet probably weighs a lot less than you did, even back then, meaning it takes much less alcohol to make them dangerously sick. Keep those wine glasses far out of reach of your pets in order to avoid any issues. Well, maybe not any issue: We can’t promise that this will stop you from getting embarrassingly drunk at a holiday party this year.

L’Oréal’s New Wearable Sensor Keeps Track of Your Daily UV Exposure

L'Oréal USA
L'Oréal USA

Anyone who has ever suffered a sunburn knows that too much exposure to UV radiation is bad for your skin. But in the moment, it can be hard to tell when you’ve gotten too much sun—especially during the winter, when you might not think you need sunscreen. (In reality, snow reflects up to 80 percent of the sun’s UV light, so you may end up getting hit with the same rays twice.) A new wearable sensor spotted by Wired aims to make understanding your sun exposure a whole lot easier.

L'Oréal’s new La Roche-Posay My Skin Track UV sensor pairs with a smartphone app to alert users when they’ve had high levels of UV exposure. Developed by L'Oréal’s Tech Incubator in collaboration with Northwestern University engineering professor John Rogers and Swiss designer Yves Béhar, the sensor measures UVA rays (which are associated with skin aging and skin cancer) and uses an algorithm to calculate UVB exposure (which is associated with sunburn and skin cancer).

The UV sensor
L'Oréal USA

At only half an inch tall and 1.3 inches long, the waterproof sensor is designed to be discreetly attached to your clothes, watchband, or sunglasses. The sensor's LED detector measures UV rays as sunlight passes through a small window in the device, then transfers the data to your phone via a near-field communication (the same technology in some hotel key cards). It stores the photons from the UV rays in a capacitor, eliminating the need for a battery.

Based on this data, the My Skin Track app can tell you how close you're getting to the maximum limit of UV exposure doctors recommend per day. It also provides updates about the air quality, pollen count, and humidity wherever you are at any given moment. Based on this information, as well as data about your specific skin type and skin tone, the app's Skin Advice feature will provide customized tips for keeping your skin healthy. It also recommends specific products—La Roche-Posay items can be bought directly through the app, should you desire.

The sensors are exclusively available through Apple stores. You can order one online for $59.95.

[h/t Wired]

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