Tinnitus and Chronic Pain Share a Common Brain Dysfunction

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Long after damage has occurred to a person’s hearing, some people still experience persistent tinnitus—the perception of a buzzing, ringing, or hissing sound—that can’t be accounted for by actual sounds. Remarkably, this phenomenon is very similar to bouts of chronic pain that persist after an injury has healed—and sometimes without the precursor of an injury.

Now researchers at Georgetown University Medical Center, in collaboration with Germany’s Technische Universität München, say they've identified a single brain dysfunction that causes both tinnitus and chronic pain. Their study, published in the journal Trends in Cognitive Sciences, revealed a common cause for these conditions, which affect 50 million (tinnitus) and 76.2 million (chronic pain) Americans alone. 

In a normally functioning brain, neural structures such as the nucleus accumbens, the ventromedial prefrontal cortex, and the anterior cingulate cortex act as “gatekeepers” to control noise, pain, and emotional signals and keep them from getting dysfunctional. In people who've suffered hearing loss, “the brain tries to reorganize and make the person hear as well as possible, but the side effect is that tinnitus noise is generated,” says Josef Rauschecker, one of the authors of the study. In people with tinnitus, these gatekeepers don't work as they should, letting through unwanted signals.

Strikingly, says Rauschecker, the brains of people who suffer from tinnitus have similar, measurable neural activity to those who suffer from chronic pain. In both cases this suggests that while there may be no external source of sound or pain—often referred to as “phantom pain”—the brain is receiving signals nonetheless.

“In tinnitus, the sound comes from the structures like the auditory cortex. It signals to the person that it’s a sound,” Rauschecker tells mental_floss. “It’s the same with chronic pain. There’s neuron activity in the brain’s pain system long after the injury has healed.”

Even more intriguing is the fact that those who suffer tinnitus or chronic pain also often suffer from depression or anxiety, says Rauschecker. This may stem from the fact that these brain structures also regulate emotions and interpret sensations. They do so via the nucleus accumbens, the brain’s reward and learning center, using the neurotransmitters dopamine and serotonin.

“The frontal cortex is part of the brain’s executive system—part of the limbic system—which regulates emotions. In tinnitus and chronic pain, we find that when these structures are impaired, there are fewer neurons and hyperactivity in the striatum that controls these emotions,” says Rauschecker. In essence, the brain is no longer able to turn down the volume, or incorrectly overemphasizes the signals, amplifying them and creating noise, pain, depression, or anxiety. 

While researchers don’t yet understand how these neural structures become broken, they are getting closer to understanding how the brain modulates—or fails to modulate—these signals. Now that they've identified the brain structures involved, their next line of research is learning how the neurotransmitters involved, such as glutamate, GABA, serotonin, and dopamine, play a role.

Through a variety of treatments, Rauschecker hopes they can learn to modulate the gatekeepers’ excessive reception and "turn down" signals of noise and pain to normal levels. "The ultimate goal is to get drug treatment and develop something that can mitigate this suffering," he says.

In the meantime, he suggests that we can all limit our potential to develop tinnitus by steering clear of excessively loud noises, or using earplugs and other means to reduce noise when possible. “Once you have tinnitus, it’s much harder to reverse.”

This Innovative Cutting Board Takes the Mess Out of Meal Prep

There's no way any of these ingredients will end up on the floor.
There's no way any of these ingredients will end up on the floor.
TidyBoard, Kickstarter

Transferring food from the cutting board to the bowl—or scraps to the compost bin—can get a little messy, especially if you’re dealing with something that has a tendency to roll off the board, spill juice everywhere, or both (looking at you, cherry tomatoes).

The TidyBoard, available on Kickstarter, is a cutting board with attached containers that you can sweep your ingredients right into, taking the mess out of meal prep and saving you some counter space in the process. The board itself is 15 inches by 20 inches, and the container that fits in its empty slot is 14 inches long, 5.75 inches wide, and more than 4 inches deep. Two smaller containers fit inside the large one, making it easy to separate your ingredients.

Though the 4-pound board hangs off the edge of your counter, good old-fashioned physics will keep it from tipping off—as long as whatever you’re piling into the containers doesn’t exceed 9 pounds. It also comes with a second set of containers that work as strainers, so you can position the TidyBoard over the edge of your sink and drain excess water or juice from your ingredients as you go.

You can store food in the smaller containers, which have matching lids; and since they’re all made of BPA-free silicone, feel free to pop them in the microwave. (Remove the small stopper on top of the lid first for a built-in steaming hole.)

tidyboard storage containers
They also come in gray, if teal isn't your thing.
TidyBoard

Not only does the bamboo-made TidyBoard repel bacteria, it also won’t dull your knives or let strong odors seep into it. In short, it’s an opportunity to make cutting, cleaning, storing, and eating all easier, neater, and more efficient. Prices start at $79, and it’s expected to ship by October 2020—you can find out more details and order yours on Kickstarter.

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Vermont Just Banned Residents From Throwing Food Scraps in the Trash

Compost is delicious trash salad for your soil.
Compost is delicious trash salad for your soil.
svetikd/iStock via Getty Images

Any Vermont resident who has carelessly tossed a watermelon rind into the trash bin this month is technically a lawbreaker.

On July 1, the state passed its Food Scraps Ban, which mandates that all leftover food either be composted or donated. Not only does this include inedible scraps like pits, seeds, coffee grounds, and bones, but also anything still left on your plate after a meal—pizza crusts, for example, or the square of Spam casserole your grandmother served before you could politely decline.

“If it was once part of something alive, like a plant or animal, it does not belong in the landfill,” Vermont’s Department of Environmental Conservation says on its website.

While it might seem like a drastic policy, Vermont has been laying the groundwork—and developing the infrastructure to maintain it—for years. In 2012, the legislature unanimously passed the Universal Recycling Law, which mapped out a step-by-step plan to cut down on landfill waste. Over the years, recyclables, yard debris, and now food scraps have all been banned from landfills [PDF]. To help residents abide by the restrictions, trash haulers have begun to offer pick-up services for the entire range of materials, and the state has budgeted around $970,000 in grant money for compost collection and processing facilities.

According to Fast Company, Vermont officials are hopeful this latest policy will help them hit their long-standing goal of reducing landfill waste by 50 percent; until now, they’ve only been able to achieve a 36-percent decrease. And it’s not just about saving space in landfills. Food decomposes more slowly in landfills, and the process produces methane—a harmful greenhouse gas that contributes to climate change. Composting those scraps enriches the soil (and keeps garbage from smelling so putrid, too).

As for enforcing the Food Scraps Ban, they’re relying on the honor code.

“People say, ‘What does this mean with a food waste ban? [Are] people going to be out there looking in my garbage for my apple cores?'” Josh Kelly, materials management section chief at the Vermont Agency of Natural Resources, told Fast Company. “That’s not the intent of this.”

The lack of consequences might diminish the efficacy of such a law in a different state, but maybe not in eco-friendly Vermont: According to a University of Vermont study, 72 percent of Vermonters already composted or fed food scraps to their animals before the Food Scraps Ban took effect.

Though Vermont is the only state so far to enact an outright ban on trashing food scraps, you don’t have to wait for your state to follow suit to make a change. Here’s a beginner’s guide to composting at home from the Environmental Protection Agency.

[h/t Fast Company]