The greatest mysteries of the human body! - Although research has allowed us to decipher lots of mysteries and some of them make total sense (it's not by chance that we sneeze, yawn, or feel pain), there remain some behaviors and phenomenons that we can't explain. Take a look at the mysteries of the human body!

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Why do we feel pain? - Pain is a universal experience and one of the earliest: we feel it at birth. According to Tor Wager, professor of psychology and neuroscience at the University of Colorado, there is currently no accepted way of measuring pain apart from asking a person how they feel.

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Stuttering - Physical and emotional factors can explain stuttering. A stutterer has their rhythm of speaking upset by psychological factors (problems with family, jealousy, insecurity, or anxiety) or physical factors (complications at birth or trauma to the head).

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Hiccups - When we eat too fast we can upset our vagus nerve, causing an anomaly between the stomach and diaphragm. As a defense, the body attacks with hiccups to resolve the situation.

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Crying - You've definitely heard people say crying is good for you. Crying is the human body's mechanism to lubricate the eyes and relieve emotional pain.

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Tears - Do you know why tears are salty? Tears contain salt and another disinfectant substance to kill germs and prevent eye infections. When tears don't work, your eyes dry out.

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Car sickness - Being in a moving vehicle can cause a disconnect between our sight and body, causing nausea and vomiting.

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Sea sickness - The autonomic nervous system is responsible for involuntary body movements. When we are in a boat, the unevenness causes a series of organic alterations, including dizziness, stomach contractions, and the secretion of gastric juices, causing sickness and vomiting.

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Goosebumps - There is a reason we get goosebumps. Our body's objective is to reduce heat loss and keep core temperature stable. The body hair of all mammals stands up when cold, creating a layer of warmth. The muscles around the hair follicles contract, but since we don't have much body hair, all we see are the goosebumps. Goosebumps are a defense mechanism in the body.

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Why don't our palms tan? - Because the skin on the palm of our hands is different: it is thicker than on the rest of the body. Soles and palms also receive less exposure to sunlight than some other body parts.

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Sleepless nights - Studies reveal that it is impossible to stay awake for more than four days without negative consequences. Our muscles and bones recuperate during sleep because sleeping produces a regenerative hormone. It also benefits our emotional state.

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Why do we dream? - We all dream, whether we remember it or not. Only in exceptional cases related to sickness do humans lose the ability to dream. There is still no explanation for this phenomenon.

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Why do we dream? - One of the most popular theories is that sleeping consolidates memories and helps to "reset" brain cells.

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What is sleepwalking? - This phenomenon is caused by a cerebral arrhythmia, which is usually hereditary, and happens more frequently in children. The motor functions wake up, while the conscience stays asleep. The sleep walker moves but doesn't know that it's happening.

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The ministry of memories - Although we know memories are kept in the brain, no expert can say with certainty where exactly. There is an assumption that memories are reflections of combinations and triggers in the brain cells, but there is no explanation for where the triggers come from.

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What is consciousness? - Thanks to the existence of consciousness, humans can create unique relationships and interactions with different actions, feelings, thoughts, and traits. Some theorists suggest that the brain has a section designed for keeping and organizing everything.

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What is consciousness? - Some theorists suggest that the brain has a section designed for keeping and organizing all this, but others defend that consciousness is nothing more than a word to simplify a series of simultaneous operations that create our perception.

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Blinking - We blink to protect and care for our eyes. By blinking, we lubricate and rest our eyes, which can't be kept permanently open.

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Blurry eyes - Our eyes go blurry for the following reasons: stress, lack of sleep, excessive caffeine or alcohol, or dehydration.

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Wrinkly fingers - When we spend a lot of time in water our skin starts to go all wrinkly. Our body does this so we can grab onto and hold things with smooth surfaces, or in other words it creates a kind of natural grip.

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The mystery of comas - A coma is the complete lack of consciousness, loss of nerve reactions, and lack of internal stimuli. Deeper comas can last for indefinite amounts of time and are caused by a lack of oxygen to the brain.

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Lefties - Around 10% of the population is left-handed. Scientists know that being left-handed is defined by genetics, meaning this trait must offer some kind of evolutionary advantage, but it's still unknown what it is.

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Myoclonus - Have you ever been almost asleep when you suddenly feel a big jerk? These are spasms produced by the body to 'resuscitate' it. When we're really tired our breathing goes way down, the body 'believes' we're going to die, and gives us a little shock.

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Why do we laugh? - Some experts theorize that laughing is a sign that a potential threat is not dangerous, while others claim it's a reaction to something that didn't happen as we expected.

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Laughing - Laughing may have come from the breathless reaction that primates display when tickled.

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Tickles - Ticklishness is related to the body's reaction to situations that cause fear and panic. We laugh when we're 'attacked' with tickles. It's the body's reaction to certain dangers.

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Why do we yawn? - When we yawn, it's not just a heads up that we're tired, it's also a way for the body to refresh the brain and lower nervous tension.

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The mystery of personality - Most scientists agree that personality comes from the brain, while others say that it's determined by the environment in which a person was raised.

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The mystery of personality - No scientist has been able to decipher the mystery of personality through cerebral analyses or genetic coding, which implies a strong advantage for the group of experts that say personality depends on environment. However doubts remain, as two people who live in identical circumstances can develop different personalities.

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Asymmetric body - The body is not perfectly symmetrical. This means that the right side of the body isn't equal to the left side. A person may have one arm shorter than the other without it being a physical defect or unevenly sized lungs.

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Sneezing - Sneezing expels bacteria and viruses from the body, as they can cause allergic reactions or infection.

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Sun sneezing - This reaction is called ACHOO and it is caused by exposure to light. The messages from the nerves in charge of vision pass through routes near to those sent by the olfactory nerve and the trigeminal nerve, which irritates the nasal mucosa.

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Appendix - The appendix is usually thought of as unnecessary to our body. However, we have this organ as a refuge for the good bacteria that lives in our intestines.

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Human bones - Our body contains bones that are some of the strongest materials on earth, even capable of supporting tons of weight. So our skeleton is its own defense.

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