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Blink. Blink blink blink.

Every minute, we blink our eyes 15 to 20 times. But we only need to blink two to four times a minute for adequate lubrication. So what's happening when we blink those other times? (Blink blink blink.)

“Many people have extensively investigated the eye movement, but most of them did not care about the eye blink,” writes Tamami Nakano, as associate professor at Osaka University in Japan, in an email. “The reason why we generate blinks so frequently has been unknown.” Even scientists assumed we only blinked to lubricate our eyes.

To understand why humans blink so much, Nakano and her colleagues asked 20 undergraduate students to watch “Mr. Bean” videos for 30 minutes while in an fMRI. (The students watched the popular British comedy because it's easy to follow without sound.) The researchers counted the blinks by measuring pupil size with near-infrared light; when someone blinks, pupil size is zero.

Nakano and her colleagues found that when we blink while paying attention to a task, we’re resetting our brain. Think of it like rebooting your computer. 

When we engage in a task, such watching a movie, our brain's attention networks are triggered. Researchers once believed that as we performed an activity, our default network of the brain (which works during downtime and is responsible for those self-reflective thoughts about what we had for breakfast or when we might go to the grocery store) lessens its activity. Researchers including Dr. Marcus Raichle, professor of radiology and neurology at Washington University School of Medicine in St. Louis and the editor of this paper, found that when doing tasks our brains switched from default mode network to the areas of the brain responsible for the activity, in a see-saw-like manner.

Tamami’s study finds that a blink switches the brain from the dorsal attention network, which helps someone attentively watch a “Mr. Bean” episode, to the default mode network, showing that the default mode network might play more active roles in various tasks than previously understood. This only occurs when we unconsciously blink; we can’t force our brain to switch networks by blinking.

“This blinking might occur at predictable points in a story, so does this say something about the way the brain is engaging a story or movie?” Raichie wonders.

He adds: “I think [the paper] provokes you to think a little bit.”

And it increases what experts know about blinking and the default mode network.

“The present study indicates that even while we pay attention to the external world, the shift from the external attentional brain network to the internal processing brain network (default mode network) dramatically occurs every time we blink,” Tamami says. “I think that blink is closely related to resetting of the brain network and chunking the flow of visual information for memory.”

The paper appears in the Proceedings of the National Academy of Sciences. 

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Got a bad memory? The brain has a unique way of helping you forget.

Say you’re on a date and you trip and fall so your dress rides up and he sees your underwear. Or your boss tells you that for the third year in the row there will be no raises. Both of these experiences feel uncomfortable, but what do you do to forget these awkward memories? Researchers found that we use two different ways -- suppression or substitution -- to avoid thinking of uncomfortable or unhappy memories.

“We assume that, in everyday life, healthy people will use a mixture of both mechanisms to prevent an unwanted memory from coming to mind,” says Roland Benoit, a scientist at the Medical Research Council, Cognition and Brain Sciences Unit at University of Cambridge, via email. “We did not know whether the processes of direct suppression and thought substitution can be isolated, and which, if any of them, would actually cause forgetting.” 

Roland and his co-author, Michael Anderson, asked 36 adults to participate in a memory exercise where half suppressed memories and the other half substituted new memories. The researchers hoped to understand how we voluntarily forget and how it affects general memory. The subjects were tested during magnetic resonance imaging procedures, or MRIs, allowing the researchers to observe how the brain works during suppression and substitution.

While both processes cause forgetting, a different region of the brain controls each one. When people suppress memories, the dorsal prefrontal cortex inhibits activation in the hippocampus, which plays an important role in retaining memories.

“It thus effectively breaks the remembering process. This, in turn, disrupts the memory representations that would be necessary for recalling the unwanted memory later on,” Benoit explains.

When it comes to substitution, the brain works a bit differently -- the caudal prefrontal cortex and midventrolateral prefrontal cortex form a network of sorts that works with the hippocampus to swap out new information with details people would soon forget.

“By just looking at how well people forgot memories, you couldn’t tell whether they had done direct suppression or thought substitution,” Benoit says. “These mechanisms are based on different brain systems that work in opposite fashion: One (direct suppression) by ‘slamming the mental break’ to stop the remembering process and the other (thought substitution) by steering the remembering process towards a substitute memory.”

Even though people exploit both to forget those nagging, unwanted memories, actively overlooking unpleasant events can negatively impact how we remember. But Benoit notes that learning how people deal with unwanted memories helps them understand how people with traumatic memories, such as PTSD sufferers, cope with remembering. 

“It is perfectly natural for people, upon encountering an unwelcome reminder, to try to put the unpleasant reminding out of mind. We all have experienced this.  Intuitively, it feels as though we solved this problem.”  

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New England Journal of Medicine, copyright 2012

This man's deep skin folds that resemble the surface of the brain are the result of a rare condition called cutis verticis gyrata.

The strange folds and furrows covering a Brazilian man's entire scalp was neither a funky new look nor a hipster trend. Rather the 21-year-old's bizarre looking scalp with its deep skin folds in a pattern said to resemble the surface of the brain is a sign of a rare medical condition known as cutis verticis gyrata.

In this week's New England Journal of Medicine, two Brazilian doctors describe this young man's case and share a picture of its odd appearance. When he was 19, the skin on his scalp started to change. It grew thicker, forming many soft, spongy ridges and narrow ruts.

Even his hair had an unusual configuration. It was normal in the furrows but sparser over the folds as is common for this strange scalp condition. No doubt, visits to the barber shop as well as washing his squishy scalp and combing his hair were peculiar experiences.

Despite the extent of his scalp affected, "the patient did not have the habit of covering his head," with a hat, for instance, says Dr. Karen Schons a dermatologist at the Hospital Universitario de Santa Maria, who examined the patient and co-authored the case study. In fact, the case study reports that "the condition did not bother him cosmetically."

Cutis verticis gyrata occurs much more commonly in men, and it typically develops not long after puberty occurs. Doctors aren't sure exactly what causes the scalp changes that lead to its weird appearance.

In this Brazilian man's case, no one else in his family had the condition, and he did not have any symptoms because of it. He was intellectually impaired and had performed poorly in school, but this was not linked with the skin folds and furrows on his scalp.

In fact, his doctors found he had no symptoms of neurological or psychiatric disorders, even though cutis verticis gyrata has sometimes been associated with cognitive disabilities or other brain-related disorders, such as schizophrenia and seizures.

"It's a benign and essentially aesthetic condition," explains Schons. Although his head probably attracted some curious stares, this man wasn't self-conscious about it. He needed no treatment.

Schons says there are surgical methods that can correct some of the disfigurement, but it may not be a good option for patients with extensive scalp involvement.

Doctors saw the young man a year after he was diagnosed, and his scalp looked the same and he continued to have no health concerns or concerns about his appearance. 

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Scientists have long assumed that fading memories are just a normal part of aging. But a new study suggests that certain 80-somethings can remember every bit as well as people much younger.

Researchers from Northwestern University found that these mentally sharp octogenarians, dubbed SuperAgers, also have brains that look very much like those of people in middle-age, according to the study published in the Journal of International Neuropsychological Society.

For the new study, researchers used MRIs to look at the thickness of the outer layer of the brain, a region called the cortex, in SuperAgers, normally aging 80-somethings, and healthy 50- to 65-year-olds.

What they found was intriguing – the SuperAgers had brains that looked very much like those of the younger people in the study and in some ways looked even healthier. 

"We were very surprised at that," says study co-author Emily Rogalski, an assistant research professor at the cognitive neurology and Alzheimer's disease center at the Northwestern University Feinberg School of Medicine

"When we looked at cortical thickness, we were very shocked to see that even with a 20- to 30-year age gap, there was seemingly no difference in the cortical thickness," she says. "In normally aging 80-year-olds, you see quite a bit of cortical thinning, even among those who are still performing normally for their age."

The cortex is key since it's involved in memory, attention, and complex thinking, also known as executive function.

Rogalski and her colleagues tested the memories and cognitive skills of 12 Chicago-area SuperAgers and 14 middle-aged volunteers. They then scanned all 26 with a 3D MRI machine and compared both groups of scans to images from normally aging 80-somethings that came from a national data bank.

Finding a group of SuperAgers was no easy task, however.

While plenty of 80-somethings showed up at the lab saying their memories were great, most didn’t remember as well as healthy middle-aged people do.

"We weren't even sure if we would be able to find any SuperAgers since we set the bar so high," says Rogalski. "They had to be as good as 50- to 65-year olds. We screened 300 people who thought they had good memories and found 30 SuperAgers."

And the MRIs showed why the 30 SuperAgers were so mentally sharp.

Rogalski found the SuperAgers' cortexes were as thick as those in people 20 to 30 years younger.

Experts believe that shrinking cortexes are a sign that cells are shriveling and dying with age - sometimes killed off by the same abnormal proteins as you see in Alzheimer's brains. One finding that really surprised Rogalski and her colleagues: a region deep in the brain, called the anterior cingulate was actually larger in SuperAgers than it was in middle-aged folks.

The anterior cingulate is very important for attention. Studies have shown that one of the reasons memory fails as we age is that we can't focus as well as we did when we were younger.

"If I were to tell you ten things you need to pick up at the grocery store and then the phone rang and you got distracted talking to your best friend you'd probably find it hard to remember those ten things when you got to the store," Rogalski explains. "That wouldn't mean your memory was bad, but rather, that you weren't able to focus on the task."

Rogalski hopes the new research on SuperAgers may help scientists unlock the secrets of these "youthful brains" and find ways to protect us against from age-related damage.

"This is the first step in a new way of looking at this - a road less traveled in aging research," she says. "Instead of looking at what is going wrong with the brain, we want to know what is going right."

As for why some people are SuperAgers and some aren't, the research team can't provide any answers at this point. It could be all related to genetics or a combination of genes and the environment: no clues popped up during the SuperAger's interviews that set them apart from people who had aged normally.

But the question of whether there's something we can do to keep mentally sharp is something Rogalski is hoping she'll be able to answer as she continues to study the SuperAger phenomenon.

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To most readers, this text looks black and white. But to a few, each letter possesses a different color, and reading becomes more than what’s in black and white.   

Those who read in color live with grapheme-color synesthesia, where the brain assigns colors to letter and numbers. Some synesthetes say words possess colors, too (someone might say truth looks gold, for example). Overall, 4 percent of the population experiences a form of synesthesia with 1 percent living with grapheme-color synesthesia.

Synesthesia gives many people a richer experience and it’s believed to be mostly harmless and fixed—people either have it or they don’t.

Until now.

Researchers at the University of Amsterdam found that people, without a history of grapheme-color synesthesia, who read books with some colored letters, associated those letters with the correlating hues. This is the first time anyone has taught synesthesia by reading books. 

“Whenever we give a talk or lecture, people ask if they can learn synesthesia,” says Olympia Colizoli, a doctoral student in the brain and cognition department at the University of Amsterdam.

“Most people would never want to give up their synesthesia and can’t imagine not having these experiences.”

To test whether people could learn grapheme-color synesthesia, Colizoli asked 15 subjects to read books that had four frequently occurring letters paired with four commonly seen colors. Each participant selected a book from Project Gutenberg and Colizoli applied color to the book (prior to the experiment she colored every letter in a book but it made it very difficult to read). Colizoli’s interest isn’t simply professional; she has "time form" synesthesia, which means she sees periods of times, such as days, weeks, or centuries, as shapes.

“Even though [synesthesia] seems to run in families and the evidences suggests it is genetic, language is learned and it comes from the environment … no one is born with the letter a in their brain,” she says. Yet, there seems to be little understanding of the role of environment and synesthesia. 

Prior to reading the colored book, Colizoli asked the participants to take a modified Stroop test, which detects grapheme-color synesthesia, to assure none of the subjects had it. In a modified Stroop test, people look at the words printed in different colored ink. Grapheme-color synethetes have delayed responses when identifying the letters’ colors.

After completing the book, the subjects re-took the Stroop test and showed behavioral signs of synesthesia. Colizoli does not believe these effects are permanent, noting more research needs to be conducted. She and her colleagues also replicated the results with participants who read in Dutch.

“We are bombarded by colored letters all the time,” Colizoli says. “It is interesting to see how adaptive [synesthesia] may be.”

Colizoli also asked the subjects if they noticed any differences since the experiment and they gave a variety of subjective responses (much like synesthetes would). One person claimed to dislike orange until reading in color, while two subjects say they now read faster. Another woman, a musician, enjoyed reading in color so much she asked if Colizoli could print all her sheet music in color for her. (This is not uncommon; artists frequently claim to be synesthetes. Vladimir Nabokov saw the alphabet in rainbow colors with each letter appearing the same shade each time he saw it.)   

“She could remember the music better and fell in love with it. Some people were really sensitive to it.”  

The paper appears in the online journal PLoS ONE. If you want to try reading like a grapheme-color synsethete, check out this link.

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It's not that he's untrustworthy, it's just that he's thinking.

Whenever I’ve watched video of myself on TV, I think I look shifty-eyed. I’m asked a question and my eyes dart away from the camera into which I’ve been told to look. At the time, I don’t know I’m doing it, but I am.

Psychology professor Howard Ehrlichman of Queens College, City University of New York, has been studying eye movement since the 1970s. In a recent article in Current Directions in Psychological Science, he reviewed some of his work, including recent findings, and argued there’s robust evidence that I’m not being shifty-eyed at all. I’m just thinking. More specifically, I'm accessing long-term memory.

“There’s no way to prove this is universal,” Ehrlichman says. “But I can say that you can see it just by looking at people on TV, and in interviews. I am convinced it is universal.”

Ehrlichman is referring to saccades, rapid eye movements that disengage the focus of one’s vision, often moving down and away from, say, the eyes of a person to whom you are talking. Or a TV camera.

Over the years, there have been a number of seemingly logical explanations for the darting eye phenomenon. Humans place great importance on the eyes of others -- it’s part of how we determine friend from foe or intuit what others are thinking. Because this requires brain power and focus, many believe we have to disengage in order to direct our thoughts elsewhere. Another theory suggests that the direction of eye movement is related to the hemisphere of the brain we're accessing. That idea even showed up as a plot point in an episode of “The Mentalist.”

Sadly, Ehrlichman, says, “people in law enforcement do believe that,” and think they can tell if somebody is telling the truth or not. But during his work for his Ph.D. dissertation he found little evidence to support the idea.

In fact, Ehrlichman’s research shows that these eye movements have nothing at all to do with vision or hemispheres. He speculates the intermittent eye movements are an evolutionary holdover.

Most animals are what Ehrlichman calls “sensory/motor machines.” They are constantly scanning and reacting to the environment, looking for food, say, or trying to avoid danger. When they find what they are looking for, they fixate on it.

Our brain’s long-term memory is like an internalized landscape. We don’t need our eyes to scan it, but “our eyes go along for the ride,” Ehrlichman says, even if we’re not looking for anything visual.

Ehrlichman and his colleagues proved the saccades are unrelated to actual vision by putting people in dark rooms, alone. “We see this effect even if they have closed eyes and they have nothing to disengage from,” he says. “The pattern is the same as when people are sitting with their eyes open.”

In one experiment, subjects were asked to name things according to visual properties, like “green” or “triangular” versus naming words meaning the same as “pleasant.” The visually-related items like “green” evoked no eye movement. But when subjects searched their brain data banks for words matching pleasant, the saccades were obvious.

Similarly, when subjects were asked to visualize their living room and describe it, which you’d think would lead to lots of eye movement as they mentally scanned the room, there was virtually no saccade activity.

“We think once they retrieve the image, they can move through it without searching long-term memory,” Ehrlichman explains.

On the other hand, when an answer to a question is right in front of us, say if we’ve just rehearsed a Q and A, we don’t need to scan our internal memory landscape. We can pop out an answer to a question and maintain our focus.

So rather then being shifty, eye movements could actually mean somebody -- including yours truly -- is simply being thoughtful. 

Brian Alexander (www.BrianRAlexander.com) is co-author, with Larry Young PhD., of "The Chemistry Between Us: Love, Sex and the Science of Attraction," (www.TheChemistryBetweenUs.com)  to be published Sept. 13.

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Questions about sexual desire and love have plagued humans for eons. While poets, musicians, and artists believe love lives in the heart, scientists know it exists in the brain. And sex? Apparently, that urge resides in the "little brain" or the bed or maybe a barn. It gets a little confusing what with those tired old adages about cows and free milk (or pigs and free sausage).

34873.000000 / Getty Images stock

He wants you, but does he love you? A new study finds love and sexual desire are controlled by the same part of the brain.

Now a new study has found that the same regions of the brain that control love also control sex -- indicating that sexual desire can actually morph into love. That's right. If a woman has sex with a man, he might not only buy the cow but love the cow, as well.

“Love and sex are clearly overlapping and they are different,” says Jim Pfaus, a professor of psychology at Concordia University in Montreal who's been studying love and libidos for more than a decade. “You can have desire for sex without love.”

But sex can also be the start of a beautiful relationship.

How does all of this work?

The brain's insular cortex (or insula) and the striatum play a role in both sexual desire and love. The insula is nestled deep within the cerebral cortex and influences emotions. While the striatum resides in the forebrain and receives messages from the cortex.

In order to map out the location of sexual desire and love, researchers reviewed 20 studies that used fMRI technology. First, they looked at the regions of the brain that lit up when sparked by love. They then compared the findings of all the papers to see what regions were activated when someone felt aroused or amorous.  

What they discovered was a bit surprising -- love and sexual desire both activate the striatum, showing a continuum from sexual desire to love. Each feeling impacts a different area of the striatum.

Sexual desire activates the ventral striatum, the brain’s reward system. When someone enjoys a great dessert or an orgasm, it’s the ventral striatum that flickers with life. Love sparks activity in the dorsal striatum, which is associated with drug addiction.

“You don’t make a connection that love is a drug; it acts just like drug addiction," says Pfaus. "Anyone who has had someone break up with them feels like a drug addict in withdrawal. You end up getting cravings.”

But it doesn't stop there. The researchers also saw an overlap between sexual desire and love in the insula.

“[The insula] translates emotional feelings into meaning,” explains Pfaus. “You take the internal state and give it external meaning.”

The areas of overlap indicate that sexual desire transitions into love in many cases, and the feelings aren’t separate.

“Even love at first sight, can it happen? Of course it can happen," says Pfaus. "And when it does happen, do you want to play Scrabble with each other? When it happens, you normally want to consummate it.”

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Wake up, folks: There is no health risk in rousing a sleepwalker from their somnambulistic stroll. Well, no risk to them, anyway. You, on the other hand, might suffer a swift, roundhouse kick to the dome.

Long-repeated medical myths have held that if you forcibly snap a sleepwalker back to a wakeful state it will A) induce a state of shock or possibly even insanity, B) give them “lockjaw,” and, C), our personal favorite, cause their soul to become trapped outside their body. The truth matters now more than ever: On Monday, the Stanford University School of Medicine released new research estimating that 8.5 million U.S. adults (3.6 percent of the grownup population) went sleepwalking during the past year -- a far higher rate of nocturnal wanderers than previously thought by doctors. 

“It’s not dangerous for the sleepwalker to wake him up,” said Dr. Mark R. Pressman, a psychologist and sleep specialist at Lankenau Hospital in Wynnewood, Pa. “You’re not going to do them any harm.”

But there are two potential pitfalls in attempting to yank them back to the conscious world. First, sleepwalkers take their short journeys with eyes open yet without turning on a key part of their brain -- the frontal lobe, a portion that controls social interaction. They are momentarily trapped in an altered, gray state that falls between alertness and full sleep, making them quite difficult to bring back to the real world, Pressman said.

“You just can’t talk to them and say ‘Hey!” and have them wake up,” Pressman said. “I’m not even sure where that myth began that you shouldn’t wake them. But the more you dig back (to try research that legend), the more you’ll find that sleepwalking once was thought to be mixed in with spirits and demonic possessions.”

Most sleepwalking episodes last only seconds or a few minutes, ending with the person either sitting or lying on the floor and returning sleep or eventually trudging back to bed.

“It’s very likely to go away on its own while the family is watching,” Pressman said.

You can try to verbally redirect a sleepwalker -- especially a child -- by standing a short distance away and speaking to them in short, easy commands: “Stop, turn around, go back to bed.” But don’t expect them to answer or even to recognize you, Pressman said. Those particular neurons are still snoozing. “Hopefully they turn around and go the other way.

“There’s really no reason to dive in and stop it unless the sleepwalker is about to climb out a window or fall down some stairs. If that’s the case, the family member doesn’t really have much choice,” he added.

If you do approach a sleepwalker -- especially if you physically block or grab one -- they may flash some "defensive aggressiveness,” Pressman said. “This is a very primitive response to what they see as a potential attacker. They may become violent.

“The first thing, obviously, is you have to protect them anyway you can. That’s the bottom line: safety. So you may have to be prepared to take a punch or kick.”

Just don’t expect your zombified loved one or housemate to offer an apology. 

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By Natalie Wolchover
Life's Little Mysteries

Our brains balk at the thought of four-dimensional hypercubes, quantum mechanics or an infinite universe, and understandably so. But our gray matter is generally adept at processing sensory data from the mundane objects and experiences of daily life. However, there are a few glaring exceptions.

Here are five common things that unexpectedly throw our brains for a loop, revealing some of the bizarre quirks in their structure and function that usually manage to slip under the radar.

Doors
Do you ever walk into a room with some purpose in mind — to get something, perhaps? — only to completely forget what that purpose was?  Turns out, doors themselves are to blame for these strange memory lapses.

Why you forgot what you were just doing

Psychologists at the University of Notre Dame have discovered that passing through a doorway triggers what's known as an "event boundary" in the mind, separating one set of thoughts and memories from the next, just as exiting through a doorway signals the end of a scene in a movie. Your brain files away the thoughts you had in the previous room, and prepares a blank slate for the new locale. Mental event boundaries usually help us organize our thoughts and memories as we move through the continuous and dynamic world, but when we're trying to remember that thing we came in here to do… or get… or maybe find… they can be frustrating indeed.

Beeps
Which bugs you more: the whine of a digital alarm clock, the sound of a truck backing up, or the shrill reminders that your smoke detector is running out of batteries? Fine, they're all terrible. Beeps are practically the soundtrack of the modern world, but they're extremely irritating because each one induces a tiny brain fart.

We didn't evolve hearing beeps, so we struggle to grasp them. Natural sounds are created from a transfer of energy, often from one object striking another, such as a stick hitting a drum. In that case, energy is transferred into the drum and then gradually dissipates, causing the sound to decay over time. Our perceptual system has evolved to use that decay to understand the event — to figure out what made the sound, and where it came from. Beep sounds, on the other hand, are like cars driving at 60 mph then suddenly hitting a wall, as opposed to gradually slowing to a stop. The sound doesn't change over time, and it doesn't fade away, so our brains are baffled about what they are and where they're coming from. 

Photos
Just as we didn't evolve hearing beeps, we also didn't evolve seeing photographs. Like your grandmother learning to use the Internet but never developing an intuitive feel for it, we consciously "get" photographs, but our subconscious brains can't quite separate them from the objects or people pictured.

Case in point: Studies show that people are much less accurate when throwing darts at pictures of JFK, babies, or people they like than when throwing darts at Hitler or their worst enemy. Another study found that people start to sweat profusely when asked to cut up photographs of their cherished childhood possessions. Lacking millions of years of practice, our brains fail when it comes to separating appearance from reality.

Phones
Do you ever feel your phone vibrating in your pocket or purse, only to retrieve it and be met by eerie, black-screened lifelessness? If, like most people, you occasionally experience these "phantom vibrations," it turns out it's because your brain is jumping to wrong conclusions in an attempt to make sense of the chaos that is your life.

Brains are bombarded with sensory data; they must filter out the useless noise, and pick up on the important signals. In prehistoric times we would have constantly misinterpreted curvy sticks in the corny of our vision for snakes. Today, most of us are techno-centric, and so our brains misinterpret everything from the rustle of clothing to the growling of a stomach, jumping to the conclusion that we're getting a call or text, and actually causing us to hallucinate a full-on phone vibration.

Wheels

Ever noticed how car wheels can look like they're spinning backwards in the movies? This is because movie cameras capture still images of a scene at a finite rate, and the brain fills in the gaps between these images by creating the illusion of continuous motion between the similar frames. If the wheel rotates most of the way around between one frame and the next, the most obvious direction of motion for the brain to pick up on is backwards, since this direction suggests the minimal difference between the two frames. [Why It Took so Long to Invent the Wheel]

However, wheels can also appear to spin backwards in real life, too, which is weirder. The leading theory to explain the "continuous wagon wheel illusion," as it is known, holds that the brain's motion perception system samples its input as a series of discrete snapshots, much like a movie camera. So our brains are effectively filming their own movies of the external world, but not always at a fast enough frame rate to perceive the wheels in the scene spinning the right way. 

For scientific explanations of five more brain farts, click here .

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• 15 Weird Things Humans Do Every Day, and Why
• Top 10 Inventions that Changed the World
• Why Aren't We Smarter?

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Actually, 90 percent of your brain is not just languishing, it turns out.

Good news for all those who ever had a teacher or a parent say “If you would just apply yourself you could learn anything! You’re only using 10 percent of your brain!”

All those people were wrong. If we did use only 10 percent of our brains we’d be close to dead, according to Eric Chudler, director of the Center for Sensorimotor Neural Engineering at the University of Washington, who maintains an entertaining brain science website for kids. “When recordings are made from brain EEGs, or PET scans, or any type of brain scan, there’s no part of the brain just sitting there unused,” he said. 

Larry Squire, a research neuroscientist with the Veterans Administration hospital in San Diego, and at the University of California San Diego, pointed out that “any place the brain is damaged there is a consequence.”

Damaged brains may have been where this myth originated. During the first half of the last century, a pioneering neuroscientist named Karl Lashley experimented on rodents by excising portions of their brains to see what happened. When he put these rodents in mazes they’d been trained to navigate, he found that animals with missing bits of brain often successfully navigated the mazes.

This wound up being transmuted into the idea humans must be wasting vast brain potential. With the rise of the human potential movement in the 1960s, some preached that all sorts of powers, including bending spoons and psychic abilities, were laying dormant in our heads and that all we had to do was get off our duffs and activate them.

“That’s a case of something one often sees, of taking something from the world of psychology and in trying to make the idea concrete, bringing in the mechanisms of biology,” Squire explained. “It’s fair to say we can all do better, and we have room for improvement through practice and developing skills, but that has nothing to do with the idea that we use only 10 percent of our brains.”

The brain, Chudler said, isn’t like a disc drive with some set amount of capacity. It’s a dynamic maze of wiring where new connections can be created in response to new stimuli, or lost with disuse. And much of it is constantly occupied not with intellectual thinking, but running our systems.

“That’s why the brain is such an expensive organ,” he explained. “It requires 20 percent of our blood supply, and it’s a real energy hog.” If we used only 10 percent of it, the brain wouldn’t require such high maintenance.

“Besides,” he pointed out, "why would our brains have gotten bigger through evolution if so much of it were going unused?”

 Brian Alexander is co-author, with Larry Young PhD., of "The Chemistry Between Us: Love Sex and the Science of Attraction," to be published September 13.

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