Blame the Brain for the Hearing Loss That Comes With Aging

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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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A Custom Wheelchair Allowed This Brain-Injured Baby Raccoon to Walk Again

фотограф/iStock via Getty Images
фотограф/iStock via Getty Images

Animal prosthetics and wheelchairs allow dogs, cats, and even zoo animals with limited mobility to walk again, but wild animals with disabilities aren't usually as lucky. Vittles, a baby raccoon rescued in Arkansas, is the rare example of an animal that was severely injured in its natural habitat getting a second shot at life.

As Tribune Media Wire reports, Vittles came to wildlife rehab specialist Susan Curtis, who works closely with raccoons for the state of Arkansas, with a traumatic brain injury at just 8 weeks old. The cause of the trauma wasn't clear, but it was obvious that the raccoon wouldn't be able to survive on her own if returned to the wild.

Curtis partnered with the pet mobility gear company Walkin' Pets to get Vittles back on her feet. They built her a tiny custom wheelchair to give her balance and support as she learned to get around on her own. The video below shows Vittles using her legs and navigating spaces with help from the chair and guidance from her caretaker.

Vittles will likely never recover fully, but now that she's able to exercise her leg muscles, her chance at one day moving around independently is greater than it would have been otherwise. She now lives with her caretaker Susan and a 10-year old raccoon with cerebral palsy named Beetlejuice. After she's rehabilitated, the plan is to one day make her part of Arkansas's educational wildlife program.

[h/t Tribune Media Wire]

Why You Should Never Shower With Your Contact Lenses In

belchonock/iStock via Getty Images
belchonock/iStock via Getty Images

Contact lenses offer a level of convenience for those with less-than-perfect vision that glasses can hardly compete with, but that doesn’t mean the daily struggle of taking them in and out of your eyes doesn’t wear on you. If you get a little lazy and decide it’s fine to leave them in your eyes during showers or pool parties, think again.

According to Popular Science, a 41-year-old woman in the UK lost sight in her left eye as a result of frequently showering and swimming without removing her contacts. The culprit was Acanthamoeba polyphaga, a protozoa that crawled into her eye and caused a cornea infection called Acanthamoeba keratitis. After two months of pain, blurry vision, and light sensitivity, the woman sought medical attention at the Manchester Royal Eye Hospital, where doctors discovered a ring shape in her left eye and a hazy layer covering her cornea. Upon testing her vision, they found that her left eye was now 20/200, which counts as legally blind in the United States.

Leela Raju, an ophthalmologist and cornea specialist at New York University, told Popular Science that the single-celled organisms “can be anywhere,” including pools, hot tubs, showers, dirty saline solution containers, and even tap water. Lens-wearers make up around 85 percent of those who get infected, and experts think it may be because the amoeba can latch onto a contact lens more easily than a bare eye.

Though Popular Science reports that Acanthamoeba keratitis only affects one or two people out of every million contact wearers each year, that’s no reason not to be careful. If you do catch it, you’ll likely need a cornea transplant, and even that won’t necessarily restore your eyesight to its previous state—after her transplant, the UK woman’s left eye now has 20/80 vision.

“It’s just a long road, for something that’s totally preventable,” Raju says. In addition to removing your contacts before swimming, showering, or sleeping, you should also refrain from reusing saline solution, make sure your contact case is completely clean and dry before filling it with more solution, and check out these other tips.

[h/t Popular Science]

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