7 annoying habits and the fascinating scientific reasons for them

Why does your co-worker constantly clear her throat? What’s behind your best friend’s Facebook oversharing? Science has the answers to these annoying habits.

Ahem, ahem! Someone who constantly clears his or her throat could have a nose and sinuses problem, called chronic rhinitis, which results in excessive mucus production. It occurs when an irritant (typically allergies) inflames the membrane in the upper respiratory tract. People with year-round allergies, like house dust mites, may have a constant build-up of mucus in their throat, which leads to that non-stop clearing. It can usually be treated with a few weeks of a strong anti-allergy medication. Another potential cause: acid reflux. When acid passes from the stomach upward into the oesophagus, the throat swells. Mucus sticks to the swollen tissues, causing hoarseness and a cough. If over-the-counter heartburn medications don’t resolve the issue, a doctor may be able to prescribe stronger treatment.

For more on this topic, here’s how to survive allergy season.

There’s always, like, one not-so-brilliant movie character who talks this way, you know? Don’t write off their intelligence: Research suggests that those who often say “like” and “you know” may be especially thoughtful. In a study published in the Journal of Language and Social Psychology, researchers examined more than 260 transcriptions of normal conversations. They discovered people who used these “filler words” tend to be more conscientious than people who don’t. Researchers say discourse markers imply a desire to thoughtfully share opinions with others, and may give someone more time to phrase something just right.

Funnily enough, “conscientious” is one of the 15 hardest words to spell in the English language.

A minute into checking social media, you find out your high school lab partner is potty-training her six-week-old Labradoodle puppy … unsuccessfully. You may roll your eyes when you get too much detail, but these oversharers reap a neurological reward when they spill their TMI news. Harvard researchers used an MRI machine to track 212 participants’ brain activity as they answered questions about their own opinions or others’ opinions. Researchers found that talking about oneself activates brain regions associated with reward (the nucleus accumbens and the ventral tegmental area). Only about 60 percent of real-life conversations typically revolve around an individual’s personal thoughts and stories, compared to 80 percent of social media communication.

Now check out these 15 Facebook hacks that put you back in control.

Distracted by a pal who just can’t sit still? Perfectionism may be an underlying cause of nail biting, skin picking or eyelash pulling, according to a study published in the Journal of Behavior Therapy and Experimental Psychiatry. Researchers asked 48 participants questions about how often they experienced certain emotions, including boredom, anger and anxiety, and put them in situations meant to trigger feelings such as boredom or relaxation. People with fidgety habits reported greater urges to pick at themselves when bored compared to when in relaxing scenarios. Researchers say perfectionists are more likely than others to become bored easily, and that behaviours like picking at nails deliver a form of reward in unsatisfying situations.

Nail-biting is a fairly unhealthy habit. Here are 10 more that are worse for you than you thought.

It may be tiresome to comfort a hypochondriac (they have a sore stomach on Monday, a swollen lymph node on Tuesday, an achy back on Wednesday) but your pal could truly believe these abnormalities are serious. This condition may be a sign of what medical experts call illness anxiety disorder (IAD), which involves excessive worry about contracting a serious illness even when no (or only mild) symptoms are present. Even doctors usually cannot calm an affected person’s fears. Though it’s uncertain what causes IAD, people with major life stress, a history of childhood abuse, or another mental disorder such as depression are at higher risk. The disorder typically appears between the ages of 25 to 35; therapy and certain antidepressant or antianxiety medications may help treat IAD.

Know someone with a trumpeting sneeze? Blame their anatomy. Irritants, such as bright light or an allergen, stimulate the nasal cavity’s trigeminal nerve and trigger a coordinated reflex from the diaphragm to the brain. Many different muscles are involved in building the pressure needed to expel the irritant via a sneeze. Individual differences in anatomy such as abdominal strength, trachea size and lung volume may cause some sneezers to be especially loud; others may naturally use more muscles in sneezing. Suspect this is you? When you feel a sneeze coming, put your index finger at the base of your nose and slightly push up. This will reduce the severity of a sneeze, or perhaps even completely suppress it.

All this sneezing puts us in mind of the 10 things you should never touch at all-you-can-eat buffets.

Road ragers may be prone to making themselves highly visible in other ways, too. In a Colorado State University study, researchers found that drivers of cars with window decals, personalised license plates and bumper stickers are far more likely that those without personalised cars to use their vehicles to express rage, such as by tailgating or honking. Researchers say both road rage and car markers are signs of territorialism, and that the more markers a car has, the more aggressively someone drives when provoked. The effect remained whether the messages were, for example, “Visualise World Peace,” or “My Kid Beat Up Your Honour Student.” Territorial people see a car as an extension of themselves, and have a difficult time viewing public property differently from private property (“our road” is “my road” in their minds.)

How are you with road rage? Find out in these 7 real-world situations that gauge how good your manners are.

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