If the sound of a co-worker repeatedly clicking his pen can send you into a flaming furor, take heart: You’re not being hypersensitive, and you’re not alone. Neurologists in the UK have spotted physical differences in the brains of people with this sound-related rage, although whether these differences are the cause or the result of the disorder remains to be seen. The scientists published their findings in the journal Current Biology.

The technical term for that noise-triggered irritation and rage is misophonia (“hatred of sound”). People who have it experience uncontrollable and intense negative emotions after hearing certain repetitive noises like chewing, lip-smacking, pen-clicking, and foot-tapping.

It’s a relatively new concept within the medical community, although people have been complaining of symptoms for a long time. To those who’ve never experienced misophonia, it may sound silly or made-up—which is what many doctors have concluded. Others have categorized it as a form of anxiety or obsessive-compulsive disorder.

The authors of the current paper wondered if the problem might not be psychological but neurological. They recruited 20 British adults with misophonia and 22 without, and gave them all questionnaires to gauge their responses to various noises. Then they put each participant inside MRI and fMRI machines and played them all sorts of noises, including the benign (a kettle whistling, rain), the universally unpleasant (a baby crying, someone screaming), and common misophonia triggers (breathing, chewing).

As the researchers suspected, the results for the two groups looked very different. People with misophonia had more myelin, or insulation, around the gray matter in their prefrontal cortex. They also showed abnormal connections between this cortex and the anterior insular cortex, which is involved in processing information and emotions.

Hearing the trigger noises caused a spike in activity in both cortices for people with misophonia. For people without it, activity only increased in the prefrontal cortex. The trigger sounds also provoked a clear stress response in people with misophonia. Their heart rates increased and they began sweating.

Lead researcher Sukhbinder Kumar is a neuroscientist at Newcastle University and University College London. He says his team’s research should reassure people with misophonia and validate the condition’s existence to their doctors.

“Patients with misophonia had strikingly similar clinical features, and yet the syndrome is not recognized in any of the current clinical diagnostic schemes,” he said in a statement. “This study demonstrates the critical brain changes as further evidence to convince a skeptical medical community that this is a genuine disorder.”

It also suggests a possible way of treating the condition. “My hope is to identify the brain signature of the trigger sounds,” Kumar said. “Those signatures can be used for treatment such as for neuro-feedback, for example, where people can self-regulate their reactions by looking at what kind of brain activity is being produced.”

Thanks to the proliferation of mattress stores of both the brick and mortar and online variety, shopping for a new bed can be overwhelming. There are so many manufacturers, models, and material types that narrowing your choices down to a half-dozen could be considered an achievement.

Why the stress? Beds are both expensive—ranging in price from $300 to several thousand dollars—and seem to harbor the promise of a better life. Sleep well and you’ll be more productive, personable, and energetic; sleep poorly and that aching back dims all of your prospects. Those consequences are often played up by mattress manufacturers, who use indecipherable industry terms (“core support,” “baffled innerspring”) to try and stand out in a crowded market. Instead, they just create further confusion.

With a little knowledge, finding the perfect crash pad doesn’t have to be so frustrating: A good, dependable mattress can be had for as little as $600 to $700. Here’s how to avoid losing sleep over your next mattress purchase.

1. DECIDE WHAT YOU DON’T WANT.

The easiest way to narrow down your choices in a store is to eliminate what you’re certain you don’t want. “Every mattress type has its own strengths and weaknesses,” David Robinson, editor and publisher of the sleep-shopping tip site SleepLikeTheDead.com, tells mental_floss. “Because of familiarity, innerspring [coil] mattresses are still the most popular. Memory foam is an option, but if you have a tendency to sleep hot, they might bother you.” Foam might be best, he says, if a couple is looking for less shifting of the mattress while one partner tosses and turns.

You might also decide to eliminate anything priced over $1000; certain mattresses made from wool, latex, or other materials you might have an allergic reaction to; or adjustable beds that rely on air bladders to tweak firmness. Some or all of these features you may find unwanted or uncomfortable: Getting rid of them can shrink a showroom fast.

2. TAKE THE GOLDILOCKS TEST.

Before you start jumping around mattresses at random, have a salesperson identify three models that represent degrees of firmness. In the lexicon of mattresses, “firm” signals a bed that will provide sufficient support and is unlikely to allow you to sink into it. “Plush” might have a polyester-stuffed top layer (sometimes called a pillowtop) that acts as cushioning, or may simply be designed to conform to your body’s imprint. Along the spectrum, there’s also medium-plush, medium-firm, extra-firm, and any number of labels that can indicate degrees of support. Leaning toward one side, however, will help narrow your choices. Back sleepers may like something more solid, while side or stomach sleepers will want to avoid firm mattresses digging into their shoulders and hips.

If you experience any post-purchase remorse over firmness, Robinson says that a mattress topper could help alleviate a stiff surface. “But not many toppers can firm up a soft mattress,” he says, making it better to err on the firmer side if in doubt.

3. GRAB A PILLOW.

Many retail outlets will supply you with a pillow and a sanitary sheet to use as a pillowcase while you try out beds. Take advantage of them, as they’ll allow you to better replicate your sleep posture in the showroom and better identify where you might need more support. You may even want to bring a friend along to help assess whether your spine is straight when lying on your side.

Whether you bring one from home or get a loaner, Robinson cautions to make sure your pillow is the proper height. “A lot of pillows depend on a person’s weight,” he says. “The heavier you are, the more you’ll sink into the mattress, and the higher your pillow loft needs to be.” People who have comfort issues with new mattresses, he says, might benefit from getting a pillow better able to support spine alignment.

4. ASK FOR SOME SPACE.

Once you’ve scouted the showroom, ask the salesperson for some time alone. You’ll need several minutes resting on each of your options to determine how they feel in different positions, if you have any trouble turning your body, or if your bed partner’s presence creates any change in comfort when both of you are present. (Some beds might sink in further with two bodies on top of them.) While it’ll never replicate a real night of sleep at home, being left to your own devices on the display models is crucial to finding the best fit.

5. DON’T LET THE LINGO SHOP FOR YOU.

You’ll often find placards in front of mattress displays touting everything from cooling gels to “hybrids” that combine foam and innerspring coils for maximum luxuriating. “Manufacturers want to seem different from competitors, but they all pretty much refer to the same ideas,” Robinson says.

Read up all you like on features and materials, but try to do it after you’ve tested the bed out first. None of the manufacturer’s “patented” hype means anything if you don’t find it comfortable.

6. CHECK THE HEIGHT.

When your new mattress (which could be a foot in height) is placed on a frame or box spring foundation—or both—you may find that getting in and out of it becomes problematic. Be sure you can climb in and out comfortably, and consider whether older or smaller pets might run into issues sharing a nap with you at home. Also keep in mind that older fitted sheets may not accommodate newer, thicker mattresses.

7. DON’T FORGET ABOUT THE BOX SPRING.

While it can add another hundred dollars or more to your tab, you don’t always want to skip on a new box spring. These wooden frames support your mattress: Using the older, sagging model you already have could cause problems with your new bed. In some cases, manufacturers might even require you to buy a new box spring in order to maintain warranty coverage, although Robinson cautions that some salespeople might be exaggerating that missive in order to move more product. (Check with the supplier.) Also, decide whether your home’s layout requires a split box: that’s a box spring split in half to make navigating tight household corners easier.

While there’s not normally much else to consider in a box spring, some salespeople might try to turn you on to the idea of an adjustable base, which uses motors to make the head and foot of the bed rise 40 to 70 degrees. “These are very popular,” Robinson says, “and can help people who have difficulty getting in and out of bed” or who have health issues. But since they can also add hundreds to the cost of the bed set, carefully evaluate whether it’ll be of any real use to you.

8. KNOW YOUR (EXTENDED) WARRANTY.

As with cars, homes, and electronics, buying a bed can often mean deliberating over a store’s extended warranty. Most beds come with hefty 10- to 25-year warranties and are adequate for most consumers, Robinson says, but may not cover damage beyond premature sinking of the mattress. A store policy—which can sometimes cover spills, burns, or tears—might offer a little more. Ask for a brochure to read the fine print before committing.

9. HAVE A PLAN FOR YOUR OLD BED.

Don’t just assume the store will haul away your unwanted mattress. Some retailers will refuse to take possession of used beds to avoid the potential for cross-contamination with pests in their delivery trucks or because they don’t want to bother disposing of them. If they do agree to take away your old mattress, make sure they keep new bedding sealed in manufacturer’s wrap until it’s set up in your home to avoid any cross-contamination with old bedding. If they don’t, they might still be able to put it out on the curb for you.

10. REMEMBER THAT YOU MIGHT BE STUCK WITH IT.

Before finalizing any deal, remember that mattresses aren’t easily returned. Furniture stores can take an “all sales final” approach to big-ticket items that are costly to transport, and used mattresses don’t normally make for attractive resale or discount items. Ask your salesperson what the return policy is, and whether buying the extended warranty allows for an exchange based on your desire for more comfort. (They’ll sometimes call this a comfort guarantee.) Others will grudgingly take one back but slap you with a 20 percent restocking fee or ask you keep the mattress at home for at least a month to make absolutely certain it’s not for you.

11. SKIP THE STORE COMPLETELY.

If you’ve gone shopping and found that the options are too overwhelming, you may consider joining the increasing number of consumers who are opting to shop online for beds. Casper, for instance, has made it their business to appeal to non-deciders, offering just one memory foam bed in different sizes that they’ll ship right to your door. If you’re not satisfied, they’ll offer you a free mattress topper to see if that improves your comfort. If you’re still not happy, they’ll typically take a return at no cost. Other e-mattress companies like Tuft & Needle even offer to donate your unwanted purchase to charity while still offering you your money back. It’s low-risk, but Robinson says that their one-size approach can’t make everyone happy.

Whatever you decide, don’t be swayed by salespeople who promise a perfect night’s sleep only if you’re willing to invest thousands. “You don’t have to pay a lot to get a competitive mattress,” Robinson says. “The average price for a new bed is $1600, but you can get something comparable in quality for half that if you do your research.”

All images courtesy of iStock.