It's caused by a misfire in the brain that creates hallucinations that can be visual or auditory, but usually not both. Whichever you get, the result is often a waking nightmare, with some of the most common symptoms being audible voices that criticize or taunt the victim, or even tempt them to violence. Or at least, that's how it works in America. Travel around the world, and you get a different story altogether.

A Stanford study rounded up 60 adults with schizophrenia: 20 Ghanaians from Accra, 20 Indians from Chennai, and 20 Americans from San Mateo, California. The Americans all rated their audible hallucinations as negative, if not downright f**k-awful, and considered schizophrenia a disease. But some Indians reported their hallucinations as entertaining or playful, and over half perceived them as disembodied advice from their ancestors. Of the Ghanaians, half reported the voices as "predominantly positive" instant messages from God. They didn't even regard it as a disease.

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"Sometimes the voice God even sounds like James Earl Jones. It's dope."

But even among Americans, the assholish nature of our imaginary companions looks to be recent. Researchers compiled patient reports from an East Texas hospital from the 1930s and compared them to those from the same (almost definitely haunted) hospital in the 1980s. The inner voices of the Depression era were harmless and even uplifting, offering helpful messages like "Live right." In comparison, the hallucinations experienced during the Reagan years adopted a sinister tone, urging violent acts against oneself and others.

Okay, so maybe it's a result of America's pop culture obsession with violence and retribution getting internalized by the mentally ill? But it gets weirder: A study of 1,080 schizophrenic Eurasians found that Georgian and Pakistani sufferers were seemingly immune to visual hallucinations -- they only heard voices. What the hell?

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"Man, I wish I had a picture to go with my voice."

The experts' best guess is that there's some cultural difference in how people are taught to "see" the world, and that this somehow affects what happens when your brain goes haywire. Maybe? Let's face it: At this point, any possible explanation is going to be super weird.

Toddlers are notoriously s****y at math, so if you ask one to count something, they'll probably use their fingers to keep track. It's what they have handy. Hell, the whole reason our number system is based on tens is because we have ten fingers, right? Math is the same all over the world, because we all started by counting things with our hands back in our cave-dwelling days.

And yet nearly every culture counts on their fingers differently, with disastrous consequences for World War II spies. Europeans begin counting on the left hand, while Middle Eastern cultures start with the right side. This preference is confirmed by science and known as the SNARC (Spatial-Numerical Association of Response Codes) effect. It essentially meanas that the direction in which our culture reads (left to right or right to left) has a direct, measurable impact on our idea of which side of our body we perceive to be "first."

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Don't get too uppity, lefties. You'll still die first.

Finger placement also varies. Chinese, North American, European, and Middle Eastern cultures all start with closed fists, though Europeans begin their counts on the thumb and Middle Easterners on the right pinkie. The Japanese begin on open fists, closing each finger as they tally up. But all of these cultures regard each digit as a single number. Indians, on the other hand, make use of each finger segment to allow for higher counts. Here's a primer:

Wichita State University
This one goes to 11!

The Maasai of Kenya and Tanzania make things even more confusing. Counting to two is simple enough, but after that, all hell breaks loose. To signify "three," the Maasai then curl the index finger to the thumb, as if you're trying to pull an errant thread out of your underpants. For "four," the index and middle fingers are crossed, like when you lied about brushing your teeth as a child. A Maasai "five" will get your ass beat in some countries, and the higher numbers are represented by curling the other fingers toward the thumb. Counting is like a secret goddamned code.

Meanwhile, tribal New Guineans use their entire bodies to count. Like others, their count begins on the right-hand pinkie, but they continue across the wrist, elbow, and shoulder, straight up to the dome, making use of every facial feature before descending the opposite arm and finishing at the left pinkie. This is a culture that absolutely does not believe in calculators.

bert_phantana/iStock/Getty Images
"An abacus? You mean weakness beads?"

However, all these numbering systems are infinitely more intuitive than ancient fingering methods, which look like the hand signals of a batting coach having a massive stroke:

Wichita State University
"Bob is getting emergency hand surgery. The crazy bastard tried to signal '80' yesterday."

Your memories are physical structures in the brain, but those structures are created by habits, and habits are enforced by culture. Americans and Europeans emphasize personal histories, encouraging children to reflect on their early years and their roles in specific events. Chinese children, on the other hand, are urged to think of themselves in terms of their role in their family, society, and community. There's less importance placed on individual genesis. Therefore, those early memories are not considered precious and are discarded.

Meanwhile, the earliest memories of all belong to the Maori, a culture that places great emphasis on oral history. The Maori consistently reminisce on personal as well as family history, and this tradition is instilled early. This propensity to talk about one's past early and often not only develops recall skills, but also gives memories more of a chance to survive through frequent retellings (and presumably less susceptible to bullshit embellishments).

John Alexander Gilfillan
Every Maori family dinner basically starts with a Ken-Burns-style historical retelling.

And not only do East Asian children's first memories form later in life, but they also differ in focus. Another study showed that Western kids reported emotional, egocentric memories ("I remember scream-crying in a Chuck E. Cheese's") while Eastern children recalled fewer emotions and less individualized memories ("I remember Chuck E. Cheese's"). Even the most crucial moments in our lives will be experienced and recalled differently depending on where you grew up, which makes us wonder if the rest of the world doesn't get so pissed off when their favorite cartoon series are rebooted.

Derek Abbott of Australia's University of Adelaide scoured cross-cultural data banks to compile a multilingual master list of animal sounds, organized by country. It's a great document to scroll through if you're currently avoiding life decisions. One of the things this list tells us is that, as a global community, we have no f*****g idea what dogs sound like. In addition to the examples above, in Romania, dogs say "ham," whereas in Korea, they say "meong." You may notice that neither of these is in any way similar to the sound a dog produces.

Meanwhile, the "chicken" sounds were clearly taken down at a Bluth family reunion.

Strangely, the closest we get to a consensus is on what sound a cat makes. Lots of countries agree on some variation of "meow." Unless you're Korean, Estonian, or Japanese, in which case cats say "yaong" or "nau" or "nyan," because cats in the East are clearly planning something. Similarly, every country in the world knows what a duck sounds like. Except for France, where ducks say "coin," because they are apparently obsessed with money -- a trait we normally associate with elderly Scottish ducks.

Birthdays are self-explanatory. You gain a year, once a year, on the anniversary of the day you were born. After about 16 of them, it becomes an annual excuse to poison yourself to the brink of death in celebration. Go anywhere in the world and ask somebody how many years they've been alive, and you should get the same answer. After all, the earth orbits the same for everybody.

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That includes you, leap-yearers. Knock it off with the "I'm only nine!" bullshit.

However, in an attempt to further homogenize its population, China did away with this practice and originated the East Asian age reckoning system, wherein babies fresh out the womb are already considered a year old, and everyone simultaneously levels up on Lunar New Year, regardless of what day they were actually born. So, for instance, if a baby was born a week before Lunar New Year, that seven-day-old child would turn two. And don't think you get to have a big ol' blowout every year. The Chinese only celebrate a handful of celestially significant birthdays: the first, 10th, 60th, 70th, and 80th. The 60th birthday is especially important, as it concludes one full zodiac cycle and the individual is cosmically reborn, which admittedly sounds pretty badass.

In South Korea, the first birthday, known as doljabi, is the most important, as it sets the tone for the baby's life. The child is dropped on a mat in front of several different items, and whichever one they grab determines what they will grow up to be. If this were the standard practice in America, most of us would've grown up to be Thundercats.

Little Lotus Party
Although the hammer is always a solid choice.

Previously, the Japanese celebrated a collective lunar new year extravaganza, and did not observe birthdays as we know them until after World War II. Western birthdays are now mostly celebrated by kids and presumably-broke college students, as tradition dictates that birthday guests are expected to foot all party-related expenditures.

Traditional Mongolians don't really do the birthday thing, either. They celebrate a baby's first birthday with a grand feast, but after that, children gain a year on the first lunar day of the first lunar month -- so, like werewolves, Mongolian age is very full Moon-centric. However, it's considered taboo to celebrate your 13th, 25th, 37th, and 49th birthdays. But don't worry -- those skipped birthdays are balanced out by the 61st, 73rd, and 85th birthdays, on which great banquets are thrown by the celebrant's children on a specially chosen day. Simple enough!

Wait a second. Freaking babies smile. Other primates smile; we've seen the pictures. This has to be an inborn trait. There's no way we're going to find out that some cultures scowl when they're happy, or that smiling at strangers is a way to pick a fight with them.

Thomas Northcut/DigitalVision/Getty Images
"The f**k is your problem?!"

To start, let's clarify why our primate cousins are smiling. In their world, baring your teeth is the prelude to an ass-kicking, smile or not. Displaying the teeth held together with relaxed lips -- aka the least appealing way smiling has ever been described -- is a sign of submission. So secretly, every modern smile exchange is a silent self-deprecation contest.

In Asia, smiling and other public displays of emotion are unconsidered uncouth. Even so, a smile may signify different things in the East, including sadness or anger. The Koreans even employ a proverb for the overly jovial: "He who smiles a lot is not a real man." In Vietnam, smiling can be used as an admission of guilt or a sign of submission and apology when being scolded or yelled at. In Germany or Scandinavia, smiling at random people on the street is considered something only simpleminded people do.

Albert Einstein Archives
Like this dumbass.

In Japan, emotional cues are mainly transmitted through the eyes. When assessing the states of others, Americans look at the mouth, because that's where smiles live. The Japanese, however, focus on the eyes, because smiles can be faked. (Seriously, try faking the eye part of a smile. You don't even need a mirror to know you're blowing it.) Furthermore, Westerners overemphasize the importance of individual features, while East Asians concentrate on the interplay of facial features.

The difference even extends to emoticons. In Western cultures, the emotion of an emoticon is conveyed by the mouth, whereas Eastern cultures put all the emotion into the eyes:

Organic Korean
"Yeah, Stonehenge totally makes me ... sad ... too."

Unfortunately, smile-shy countries are less popular with American tourists, who believe that people who don't smile are unfriendly and sad, because Americans just assume that their culture and customs are the baseline for the entire world. Some countries have tried to rectify the problem to hilarious effect. In 2009, the perennially gloomy citizens of Paris were advised by the government to smile more, in an attempt to boost the City of Light's global appeal. National agencies even hired "smile ambassadors" to stand at hot spots and grin at tourists. And as a prelude the 2008 Olympics in Beijing, China's Changping Vocational School relentlessly drilled 380 hostesses on Western ingratiating techniques, which included smile lessons.

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"That's right, nice and natural. NOW TELL ME WHAT SOUND A DOG MAKES."

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