Have you ever wondered why our body does some of the strange things that it does? Like, why your brain has that “freezing” sensation when you eat something cold or why we cry when we’re laughing at something we find super hilarious? We’ll, there actually is scientific reasoning behind all these baffling body-quirks. Read on to find the answers.
What Causes Goose Bumps?
Piloerection aka: goose bumps pop up when you’re cold or afraid. A tiny muscle at the base of each body hair contracts; together, they appear as naked bumps on the flesh. They made sense eons ago, when humans still had a natural “fur coat.” Back then, fluffing your ruff would warm the body by trapping an insulating layer of air between the hairs. And standing your hair on end was intimidating to predators or enemies (picture a cat facing off with a dog). Evolution has since stripped humans of their pelts.
What Causes Brain Freeze?
Another frozen treat and another brain freeze. “Ice cream headaches” happen when something cold touches nerves in the roof of the mouth, triggering blood vessels in the front of your head to constrict — producing pain. Try this quick pain relief trick: Press your tongue to the roof of your mouth to warm it up.
Why Do You “Laugh Until You Cry”?
Experts don’t really know, but laughing and crying are similar psychological reactions. We associate crying with sadness, but tearing up is an even more complex human response. Tears are triggered by a variety of emotions. As it turns out, that’s good, because both laughter and crying can ease a stressful experience, probably by counteracting the effects of cortisol and adrenaline. So if you ever find yourself laughing until you cry, count yourself lucky.
Why Do Onions Make You Tear Up?
When you cut into an onion, enzymes are released from the onion that produce a gas called propanethial sulfoxide. Once that gas reaches your eyes, it reacts with tears to produce a mild sulfuric acid. And that hurts. The brain then signals the eyes’ tear glands to produce more liquid to flush the stuff out. The more you chop the more irritating gas you produce and the more tears you shed.
Why Does Your Eyelid Twitch?
Eyelid twitching is a common condition also known as eyelid myokymia. Not a lot is known about eye twitches, but experts know that fatigue, stress, and caffeine all increase the likelihood of the pesky twitching. So do eyestrain, poor nutrition, excessive alcohol intake, and allergies. Fortunately, eye twitching is almost always benign and usually goes away by itself. To put an end to a bout of the eye flutters, cut down on coffee and alcohol and give your eyes–and your whole body–a good night’s rest.
Why Are You Always Cold?
The hypothalamus in your brain regulates body temperature which signals the body to give off heat in warm conditions and trap heat (or shiver, generating heat in muscles) when it’s cold. Iron plays a role in this process, so people with anemia (commonly caused by iron deficiency) often feel chilly. Poor circulation–due to high blood pressure or medications, among other culprits–can leave the extremities deprived of heat. An underactive thyroid gland can also slow a person’s metabolism to a point where the body generates insufficient warmth. A recent study suggested there may even be a genetic predisposition to toward tolerance of cold
What Causes “Pins and Needles?”
Paresthesia, aka pins and needles are caused by blocked blood flow to a pressed nerve. If you sit too long in a strange position you may press hard enough on a nerve to interrupt its signaling to the brain, causing your feet, for example, to go numb. This usually occurs in the hands, feet, and ankles. That crazy prickly sensation is the resumption of pain messages to the brain. Simply changing your position is almost always enough to allow the nerve to resume communication.
Why Do You See Halos Around Lights?
Spherical aberration is the technical term for this common condition. In daylight, the pupil narrows to a very small opening, allowing light to hit the very center of the lens. At night, when the pupil dilates to allow maximum light to enter, your eye is using a much larger swath of its lens to see. As you get off center, those light rays won’t be focused to the center of the eye. You see circles, because your lens is round. Almost everyone sees these rings on occasion.