00:00Take a look at your fingernails. Are they a bit ridged?
00:03There are a bunch of reasons why that might happen, and it has nothing to do with your manicure skills.
00:09To start with, know that your fingernails might be a good indicator of any health problems.
00:15But those vertical ridges are normal, especially when you get older.
00:19It's your skin's way of showing it needs to slow down.
00:23New skin cells don't get produced as rapidly as they used to,
00:27so you get this texture on your fingernails.
00:30However, if this is just one of many other weird symptoms,
00:34it might be more than just a sign of aging.
00:37For instance, it may be a sign of a chemical imbalance,
00:41which can give you vertical ridges, but also make your nails look spoon-shaped.
00:46Don't put stuff in your ear. You know that.
00:49Even with Q-tips, you should always be gentle when using it.
00:53Otherwise, you could end up causing more harm.
00:56What's even more interesting is that sticking things in your ear
00:59can trigger a weird coughing mechanism, also known as the Arnold's Ear Cough Reflex.
01:05Turns out that the ear has a say in coughing because of the vagus nerve.
01:10This long nerve road from the brain to the belly.
01:13It taps the ear, handles the voice box, and takes a detour to the stomach.
01:18This nerve runs all sorts of daily activities without us being able to control it,
01:23from speaking to eating, and even bathroom breaks.
01:27Now, the part that connects it with the ear is Arnold's nerve.
01:31This one deals with touch sensations.
01:34Stick something in your ear and it can get triggered.
01:37And it's precisely that tickle sensation that can make you cough.
01:40Think of it as a brain blip, tricking your body into believing it's got something in the throat.
01:47You end up coughing as a way to kick out the imaginary intruder.
01:52You might be missing a muscle in your arm too, but it's okay.
01:57You were most likely born that way, and you're also one of many.
02:00It's called the palmaris longus tendon, and about 14% of the population doesn't have it.
02:07Here's how you can test it out.
02:09Gently flex your wrist and touch your pinky with your thumb.
02:13If you can see a little tendon protruding on the inside of your wrist, you've got it.
02:18If you don't, that's fine.
02:19For the most part, this muscle doesn't increase the performance of our arm.
02:24Here's another little experiment you can safely try at home.
02:28Check which one of your nostrils is your favorite.
02:32Even though you probably didn't even know you had one.
02:35Stand in front of a mirror, breathe out through your nose, and watch how the fog forms.
02:41Sure, there will be two marks on the mirror, but for most people, one's gonna be bigger.
02:46That's because we usually breathe more from one nostril at a time.
02:51Some doctors say that about 75% of our breath comes from one single nostril.
02:57It also switches sides during the day, in a process called the nasal cycle.
03:02So why not both nostrils at once?
03:05Well, it's generally believed to be all about moisture, preventing one side from getting too dry.
03:11The only time you might be able to notice the difference is when you're trying to fall asleep.
03:16Lie on your right side, and you'll see that gravity makes one part of your nose work harder.
03:21Speaking of sleep, whenever you're trying to get some rest at a new place, only a part of your brain will actually get some quality sleep.
03:32That's because our brains are wired to remain a bit more alert when we're in an unfamiliar place.
03:38This discovery explains why we often wake up feeling groggy after a night in a new apartment.
03:44This is a feature we share with birds and sea creatures who can half-sleep, keeping an eye out.
03:50Back in the day, sleep researchers noticed this and named it the first night effect.
03:56Whenever someone participated in a sleep study, they noticed the quality of their rest was so bad, they had to trash the data.
04:02But, after the first night, it seemed to level up.
04:06We do this because back in ancient times, the chances of getting attacked by predators during the night were way higher.
04:13So, it made sense to keep that part of the brain on guard for any dangers.
04:18Unfortunately, there's no switch to flip this off.
04:21So, after a night in a new place, just know you'll need way more coffee.
04:25And maybe hit that subscribe button to stay updated with our newest videos for a nice pick-me-up in those snoozy days.
04:33It's possible that each time you're getting ready for a workout, your heart is already acting up, even though you aren't technically moving your muscles yet.
04:43That's because of an effect called anticipatory rise.
04:47In simple terms, it's like your brain is sending directions to your heart, telling it to get ready.
04:52These directions come in the form of chemicals, like noradrenaline and adrenaline.
04:57It's helpful because that kick in the heart rate means more blood pumping out every minute, which is good for your muscles.
05:04The increased blood flow delivers oxygen and prepares your muscles to put in the required effort.
05:10The better shape your heart's in, the smoother this whole process goes.
05:14All of us have heard stories about regular people being able to lift heavy objects in stressful situations.
05:21You know, like a mom being able to lift a car to save her kid.
05:25Some are calling it hysterical strength.
05:27And it can't really be tested out in a lab, because you can't just fake a sense of imminent danger.
05:34It's more about real, spontaneous moments that somehow trigger this hidden superpower.
05:39Well, even though it sounds like people are lifting a ton of weight, they're not that strong.
05:44Take the classic car lift scenario.
05:47You'd think they're lifting the whole car, but it's more like lifting a part of it.
05:52Most wheels are still on the ground.
05:54Plus, cars aren't evenly heavy everywhere.
05:58The engine's the densest part, not the area that's often being lifted.
06:03As for the hysterical strength, it's more about realizing we're stronger than we think.
06:08Our muscles usually use the least effort needed for everyday tasks.
06:12But when we need to go all out, we can recruit more muscle power.
06:17You see, our bodies are very efficient.
06:20Why use all our muscles when lifting a coffee cup?
06:24Even when we feel exhausted, chances are, we're not.
06:28Researchers say we might only use 60 to 80% of our muscle strength, and that's reserved for top athletes.
06:36Apart from efficiency, our brains also don't go full power on our muscles
06:40because of a built-in safety mechanism.
06:43If we used all our strength, we could easily hurt ourselves.
06:47The simple game of peek-a-boo isn't just a fun pastime for babies.
06:52They love it so much because it can help with their development.
06:56You see, it's not just about covering and uncovering faces.
07:00It helps them better master the skill of visual tracking.
07:04It's also useful for understanding the concept of object permanence.
07:08Just because they can't see something, it doesn't necessarily mean it's gone forever.
07:13This knowledge that objects exist even if they're out of sight will increase their problem-solving skills when they get older.
07:21Playing peek-a-boo is also a good way to exercise various positive emotions.
07:25They go from surprise to anticipation to excitement and happiness.
07:32Some say they can do just fine with just 4 hours of sleep every night.
07:37But scientists say most of us adults need a good 6 to 8 hours.
07:42And the reality is that anything less than this average can lead to serious sleep deprivation.
07:48That is, of course, if you're not one of those super sleepers.
07:51These people are magical beings who thrive on less than 6 hours of sleep each night.
07:57They function properly on that little, but they also naturally wake up after just 4 or 5 hours.
08:04Only 1 to 3% of the population can claim that title.
08:08Also, know it's genetic.
08:10You can't train yourself to be one.
08:12You can't train yourself to be one.
08:14You can't train yourself to be one.
08:15You can't train yourself to be one.
08:16You can't train yourself to be one.
08:17You can't train yourself to be one.
08:18You can't train yourself to be one.
08:19You can't train yourself to be one.
08:20You can train yourself to be one.
08:21You can train yourself to be one.
08:22You can train yourself to be one.
08:23You can train yourself to be one.
08:24You can train yourself to be one.
08:25You can train yourself to be one.
08:26You can train yourself to be one.
08:27You can train yourself to be one.
08:28You can train yourself to be one.
08:29You can train yourself to be one.
08:30You can train yourself to be one.
08:31You can train yourself to be one.
08:32You can train yourself to be one.
08:33You can train yourself to be one.
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