As a neurologist, Dr. Sam Berkovic sees many patients who frequently faint. These people say they feel weak in the knees after experiencing something unpleasant, perhaps seeing blood or being dehydrated. He began suspecting that fainting, also known as vasovagal syncope, runs in families.

And he appears to be on to something. A study by Berkovic, published today in the journal Neurology, finds that fainting may be genetic, and for some families only one gene causes it.

On average, about a third of the world’s population are frequent fainters. ”(I)t’s usually trivial, not a serious health issue,” says Berkovic, a laureate professor in the department of medicine at Austin Health at the University of Melbourne in Australia.

People who suffer from vasovagal syncope faint after encountering a trigger, which can be something like seeing blood, being dehydrated, feeling stress, or experiencing pain. While losing consciousness feels scary, vasovagal syncope is normally harmless. But Berkovic believes that understanding why people swoon might mean researchers can someday prevent them, saving fainters from accidents—and embarrassment.

To determine genetic underpinnings, Berkovic and his colleagues recruited 44 families with members who shared a history of fainting. Six of these families had a large number of fainters, bolstering the researchers’ belief that fainting was genetic. One family had 14 members who experienced vasovagal syncope and another had 30 individuals from three different generations.   

The researchers gathered DNA samples and also asked the family members to answer questionnaires about their general health, the onset of fainting, and what triggers their swoons. After analyzing the DNA, the researchers found that six of the 44 families showed strong evidence of a genetic link. And, the family of 30 fainters all shared a strong linkage to one chromosome, 15q26. These results show that a vasovagal syncope is genetic.  

While discovering a genetic link for fainting wasn’t a surprise, Berkovic admits he was amazed to learn that the triggers differed among family members. If a mother faints at the sight of blood, for example, her son might swoon when dehydrated. Berkovic says we don’t fully understand how triggers work, but this paper suggests it doesn’t seem to be controlled by genetics.

He hopes that future research will shed light on what controls the triggers, allowing for a better understanding of vasovagal syncope. Some people’s aversion to blood, for example, is so severe they refuse blood tests because they fear fainting. By understanding the triggers, researchers might be able to treat them.

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From time to time Dr. Oliver Sacks is haunted by musical symbols: notes, clefs, staffs and bar lines all fly by his eyes uninvited and in rapid succession. The celebrated neuroscientist can “see” the imaginary scores despite, or perhaps because of, his partial blindness.

As it turns out, Sacks is not alone. People from around the world have been writing him letters describing the music-oriented hallucinations that come unexpectedly and unbidden.  He’s described their experiences in a new report published in the journal Brain.

“When they happen you’re startled,” says Sacks, a professor of neurology at New York University and author of the 2012 bestseller, “Hallucinations.”

“It’s different from imagination. When you imagine something, it’s yours because you have imagined it. But when this happens to you, you’re startled. You wonder, ‘Who ordered this up? Where did it come from?’”

More often than not, people who are visited by these hallucinations of musical notation have problems with their eyesight like Sacks, but the visions can come to people suffering from Parkinson’s disease or even just a fever, he says. While they often come to people who are musically oriented, they can also appear to those who can’t read a note.

Sacks describes the case of 75-year-old Ted R., who developed Parkinson’s in his early 60s. Despite the disease, Ted is still an active scholar and writer - and a gifted pianist who’s been having musical hallucinations for the last two years.

The first time the musical notations appeared, he’d been reading a book. He turned away from it for a few seconds, and when he glanced back at the pages in front of him, the text had been replaced by a musical score.

Ted wondered whether the score was actual music and has tried many times to either transcribe or to perform it, but so far has found that “the music is scarcely playable because it is highly ornamented,” Sacks writes.

But Ted perseveres. Having discovered that he can summon up the hallucinations by staring at a text on a printed page, he will put a newspaper on his music stand and wait for the notes to appear. Hampered by their complexity and the speed with which they disappear, he’s had little success and so far, no great symphony has arisen from the elusive illusions.  

Another letter writer, whom Sacks calls Arthur S., finds the hallucinations to be irksome rather than entertaining. Arthur is a surgeon and an amateur pianist who is losing his eyesight to macular degeneration. “He was quite annoyed, as they would appear on a letter he was trying to write or something he was trying to read,” Sacks says.

The hallucinations may offer scientists more than merely some entertaining stories about brain quirks. Sacks hopes they will teach us something about the networks that process musical scores. Researchers have already scanned the brains of people who hallucinate faces, Sacks says. “One finds that the part of the brain in the back of the right hemisphere that is normally responsible for recognizing faces, has taken on a life of its own,” he says.

Scanning people who suffer musical hallucinations might be even more interesting.

“A musical score is a complicated sort of thing,” he explains. “It might show us how many parts of the brain can be integrated together as they are in reading music – and also presumably in hallucinating about it.”

Sacks hopes his article will spark more research and prompt scientists to scan the brains of people in the midst of a musical hallucination. “One of my reasons for publishing this in ‘Brain’ is to say to my colleagues, ‘Hey guys, this is something interesting. Take it and run with it.’”

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A strange text message from a loved one usually means one of three things: He's the victim of autocorrect or a pocket-dial -- or you're the victim of a drunk-text. But evidence is beginning to build that a garbled text message can signify a fourth, much more serious scenario: a stroke. 

In fact, in some cases, the gibberish text may be the stroke's only visible symptom, alerting doctors to stroke-related aphasia  - in other words, problems with reading, speaking and/or writing. Dr. Omran Kaskar, a neurologist at Henry Ford Hospital, is the lead author of the new report on "dystextia," which was presented Wednesday at the annual meeting of the American Academy of Neurology in San Diego.

The first reported case of dystextia, published in December, was in a 25-year-old pregnant woman in Boston, who was diagnosed with a stroke after sending a couple of unintelligible texts to her husband. 

Kaskar describes a second case in the new report: It's after midnight and a woman gets a series of strange text messages from her 40-year-old husband, who's on a business trip to Detroit. "Oh baby your;" And then: "I am happy." Two minutes later: "I am out of it, just woke up, can't make sense, I can't even type, call if ur awake, love you."

The man visited the hospital the next day, where doctors noted some slight weakness on the right side of his face, but other than that, they couldn't find evidence of neurological problems. Until, that is, they gave him a smartphone. This is what they asked him to type: "the doctor needs a new blackberry." And this is what he actually typed: "Tjhe Doctor nddds a new bb." What's more, he didn't recognize any typing errors in his message. (Obviously, we all make bizarre typos on occasion, but what sets dystextia patients apart is that they don't see anything wrong with what they've written.)

From that clue, doctors were able to determine that he'd had an acute ischemic stroke, which means a clot was blocking blood supply to part of his brain. 

Strokes are one of the leading causes of death in the U.S., killing nearly 130,000 Americans every year, according to the latest figures from the Centers for Disease Control and Prevention. And it's not something that's only a problem for older adults -- a study published in October of last year shows that more adults younger than 55 are having strokes, up to 18.6 percent in 2005. Researchers expect that increase could be for reasons that won't surprise you - more Americans have diabetes, obesity and high cholesterol, all of which heighten the risk of suffering a stroke. But it could also be the result of better diagnosis.

That brings us back to text messages, which Kaskar urges neurologists to view as a useful new tool in diagnosing stroke because, for one, they come with a time-stamp, allowing doctors to figure out when symptoms may have started -- and that can be key in determining proper treatment. 

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When Dr. Josef Parvizi of Stanford University asked Ron Blackwell to look around his hospital room, everything seemed fine. His vision was normal. The TV looked like the TV and the “get well” balloons looked like balloons. Parvizi looked just like himself.

“Then they said ‘What do you see now?’” Blackwell recalled to NBCNews.com. “And then colors appeared and I thought that was so amazing. I said ‘How did you do that?’ Then he said ‘OK, what now?’ and I didn’t see anything different, and then he said ‘Look at my forehead,’ and his face changed. His eyes dropped, like, two inches, his nose skewed to his left." When Parvizi asked Blackwell to look at a female assistant in the room, the woman's face appeared to lift upward. 

Nothing else changed. The TV looked normal, Parvizi’s shirt and tie looked normal. Only faces changed.

As Parvizi and a Stanford colleague, Kalant Grill-Spector, detail in an article published this month in the Journal of Neuroscience, that’s because Parvizi had sent tiny jolts of electricity into a part of Blackwell’s brain called the fusiform gyrus.

Scientists have known for a while now that people, and at least some primates, have an area of the brain that’s responsible for processing faces specifically. We’ve evolved it, Grill-Spector explained in an interview, because we’re social beings. We need to know who our friends and enemies are, who’s a family member, who we can trust.

If the fusiform gyrus, located in the temporal lobe, is injured, people can lose the ability to recognize faces, even of people they’ve known for a long time. This is called prosopagnosia. People can also be born with prosopagnosia. The neurologist and writer Oliver Sacks, for example, has written about his own struggles with the condition.  

People with prosopagnosia, which can be mild to severe, can have difficulty maintaining social relationships. For example, Grill-Spector recalled a young female student who has taken part in her lab studies.

The student had a boyfriend. One day the boyfriend stopped by her room, but he’d just come from playing sports, and was wearing clothes she’d never seen. He was also wet. Missing her usual cues, she didn’t recognize him, and he realized it. That was OK, but his girlfriend thought this stranger was pretty cute and began flirting.

Blackwell doesn’t have prosopagnosia; the experiment was a bit of serendipity. The 47-year-old applications engineer for an electronics company has suffered from epilepsy since childhood. When his seizures became worse in 2010, he consulted with Parvizi.

They decided brain surgery might help. First, though, doctors had to locate the precise origin of the seizures. To do that, they implanted electrodes through Blackwell’s skull and into his brain, including the fusiform gyrus. The idea was to use the electrodes to map the location.

The diagnostic worked, but the surgery couldn’t be done because the originating area was too close to vital tissue.

But Parvizi and Grill-Spector, knowing electrodes were located in and near the fusiform gyrus, wondered if, before they were removed, the devices  could be used to map the nerve bundles responsible for face recognition.

“We need a better understanding of the neural basis of prosopagnosia,” Grill-Spector said. “If we can understand the circuit, maybe there’ll be some way in the future to stimulate them in a positive way.”

Blackwell wasn’t told what the experiment was for, so there’d be no risk he’d be “coached” into seeing facial changes. “I figured it was just more testing,” related to the epilepsy, Blackwell said.

After a series of trials, including sham stimulations that produced no effects, and stimulations of two nearby electrodes that did not cause the same kind of facial distortion effects, Parvizi and Grill-Spector concluded they’d located two critical areas in the mid and posterior fusiform gyrus responsible for accurate face viewing. They dubbed them “mFus- and pFus-faces.”

In the end, things worked out for Blackwell, too. He’s on a new drug regimen that has controlled his seizures and, he says, he’s doing “perfectly fine.”

Correction: An earlier version of this story indicated Dr. Kalanit Grill-Spector was in the room at the time of the procedure. She was not. 

Brian Alexander (www.BrianRAlexander.com) is co-author, with Larry Young Ph.D., of "The Chemistry Between Us: Love, Sex and the Science of Attraction," (www.TheChemistryBetweenUs.com), now on sale.

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Chip Simons / Getty Images stock

Your eyes are growing heavy ....

You could say it’s a nightclub hypnotist’s nightmare. He calls a willing victim up to the stage, asks him to stare at the pocket watch, and then informs the audience member that he’s now a chicken.

But instead of clucking, or doing that arm flap thing, the smart-alecky subject winks at the audience and refuses to cooperate. But why are some people tough to hypnotize, while others seem to fall under the spell lickety-split?

David Spiegel, a physician in the department of psychiatry and behavioral sciences at Stanford University, and a team of colleagues, think they’ve discovered an important difference between people who are easy to hypnotize and those who aren’t.

According to the team’s study of 24 individuals, presented in the Archives of General Psychiatry, people with a low barrier to hypnosis have more functional connectivity between two areas of the brain: the left dorsolateral prefrontal cortex -- a region vital for executive functions – and the “salience network” – parts of the brain including the anterior cingulated cortex, amygdala, ventral striatum – that assigns importance to emotional, autonomic and somatic information.

In other words, parts of the brain that are constantly on the lookout for signals, and attaching emotional meaning to the input, and part of our prefrontal cortex that develops “action plans” about how to react to such signals, are communicating with each other more powerfully.  

Spiegel used an example to explain what this means in real life. For example, a high hypnotizable person might sit down in the university library stacks to study, and lose all track of time because he’s so absorbed in the work. Or, when watching a movies, a high hypnotizable person might become so absorbed in it, he forgets it’s even a movie. 

“It’s that when you are tracking something, you’re not worried about tracking something else,” Spiegel explained.   

To figure this out, the researchers used 24 adults, mainly Stanford students, who, using a standard test called the Hypnotic Induction Profile, scored as either high or low hypnotizability.

Both groups were examined in a functional magnetic imaging (fMRI) machine. They were given no specific instructions regarding what to think about while in the machine, a “resting state.” There were no differences in physical brain structure or in the volume of various brain regions.

But there was a difference in function: The brains of people who were “high hypnotizable” showed that the dorsolateral prefrontal cortex was being functionally incorporated into the “salience network.” This didn’t happen in the low hypnotizable group.

“Normally, the dorsolateral prefrontal cortex is thinking, planning, deciding what to do next. And the anterior cingulate cortex is telling you what to be worried about,” Spiegel said. “In high hypnotizable people, these two tend to be functionally connected.”

The fact there wasn’t any difference in brain structure leads Spiegel to suggest that brain signaling chemicals might be responsible for the difference. People have different gene variants, called polymorphisms, that carry instructions for the way dopamine works in the brain. Previous studies have found that some polymorphisms are correlated with hypnotizability, cognitive function, alertness. So Spiegel thinks that’s a likely candidate to explain the difference in function between the two groups.

The study has its limitations, Spiegel admitted, like the low number of subjects, and the fact they weren’t hypnotized while in the fMRI. But the work is important, he said, because hypnosis is now often used for pain relief, to dampen anxiety in cancer patients undergoing treatment, and in psychotherapy. Knowing who’s likely to benefit could go a long way to making it an even more valuable tool.

Brian Alexander (www.BrianRAlexander.com) is co-author, with Larry Young Ph.D., of "The Chemistry Between Us: Love, Sex and the Science of Attraction," (www.TheChemistryBetweenUs.com), now on sale.

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“It was a quiet Thursday afternoon when A.S., a 68-year-old woman from a suburb of Chicago, awakened from a nap to the realization that something was terribly wrong,” begins a remarkable article in the September 11 issue of the journal Neurology.

“‘I went to lie down, and when I got up, I couldn’t find where the cabinets were, or the doors,’ she remembers. Over the next 2 days, A.S.’s confusion heightened as she increasingly lost her ability to name or even distinguish household objects that she’d been surrounded by for years.”

A.S. did not know it at the time, but she was suddenly suffering from something called Bálint's syndrome.

First described in 1907 by a Hungarian named Rezsö Bálint, people with the condition lose the ability to make sense of their visual field and coordinate their physical movements in response.

“If you ask somebody if they see a glass, or a toothbrush, they’ll say yes,” explained Loyola University of Chicago Stritch School of Medicine neurologist Murray Flaster, who is one of the article’s authors. “Then if you ask if they can pick it up, they can’t. There’s nothing wrong with their movements or their eyes. They just can’t easily understand how to reach the glass.”

The problem, Flaster said, is that one or more critical parts of the visual brain have been injured, most commonly by a stroke.

When we see normally, the data enters our eyes, travels along the optic nerve and reaches the brain. Eventually our visual cortex assembles the data – shapes, context, dimensions and so on – into a coherent picture.

A stroke or some other event can injure key areas around the visual cortex called “association areas.” “Our educated guess,” Flaster explained, “is that it is in these areas that we process visual images and relate them to a visual field. We can recognize each item. For instance, if a pen moved on my desk I would recognize it as a pen. But the ability to recognize relationships of objects and where they are becomes impaired.”

In other words, the associations between objects and their context isn’t getting made. “You cannot assemble the discrete elements,” Flaster said. “You can’t extract useful information from the image.”

It’s a little like another condition known as alexia without agraphia. There, patients can write full sentences, but they can’t read them because they can’t make sense of letters and words they’ve just written, though they can see them just fine.     

Needless to say, this is a serious problem. Thankfully, it’s also rare. Flaster suggests that a neurologist might see a dozen cases over an entire career. Because there are gradations of severity, Bálint syndrome could be missed by physicians, Flaster said. Some cases might resolve on their own, but most won’t, and there’s no cure nor therapy.

Instead, patients have to adapt. A.S., for example, puts toothpaste directly into her mouth, then grasps the toothbrush and, by trial and error, puts it in her mouth and scrubs. Once an avid reader, she now relies on audiobooks. Her family figured out that putting bright yellow tape around doorways helped A.S. navigate.

A diagnosis “can be a devastating blow” Flaster said, but patients are often also relieved to at least know that what’s gone haywire in their brains has an explanation. 

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 released Thursday.

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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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At some point most of us confuse left and right like we’re in a scene from an old Three Stooges one-reeler: “The one in your left hand!” “No, your other left!” Bonk!

It seems silly. After all, it’s not like we’re new to the concept; we’ve been using our left and right hands all our lives. Yet we sometimes flub -- some of us more often than others.

I’m not referring to people who’ve had strokes or suffered some other injury or illness. Then there’s often a clear explanation for what neuroscientists call “left-right confusion.”

But in 1978, researchers polled 364 university faculty, none of whom had any known neurological problems, and all of whom would seem to be smarter than the Three Stooges. It turned out that left-right confusion was common, especially among the women. The question was, why?

It’s now 34 years later and, said Eric Chudler, director of the Center for Sensorimotor Neural Engineering at the University of Washington, whose work depends on knowing left from right, “that’s a difficult question. I don’t know if any answer exists.”

According to M.K. Holder, executive director of the Handedness Research Institute, and an adjunct assistant professor of psychological and brain sciences at Indiana University, the link between brain “lateralization” -- the way specific functions appear to reside in left or right sides of our brains -- and handedness (or even what we mean when we say “handedness”) is still unclear.

But there does appear to be a link between degree of lateralization and confusion.

For example, left-right confusion may be related to spatial reasoning. If so, it might help explain why it’s more common in women than men; as a group, women tend to underperform on a critical test of spatial reasoning, called mental rotation, that requires subjects to mentally rotate images to tell if they’re identical or mirror images of each other.

In 2011, though, a team of German scientists disputed that connection by testing men and women who were matched in mental rotation ability before subjecting them to two standard tests of left-right confusion. (The tests require people to make a quick decision in response to directional words or symbols.) Their report, which appeared in Brain and Cognition, found that “matched participants showed robust sex differences in favor of men in all [left-right confusion] measurements. This suggests that pronounced sex differences…are a genuine phenomenon that exists independently of sex differences in mental rotation.”

The degree of asymmetry of one’s brain hemispheres, or the degree of lateralization, may be important. In 2009, British scientists found that those whose hearing was more biased toward one ear over another, a sign of asymmetry, were more likely to display confusion. Still, there’s no definitive answer yet.

Meanwhile, if you’d like to test your own degree of left-right confusion, Chudler has a test on his website.  

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

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Barf bags: They’re not just for kids anymore.

Chip Somodevilla / Getty Images file

Are we there YET? Adults are often unpleasantly surprised to discover they can develop the queasy stomach, cold sweats, dizziness and headaches of carsickness, even if they never had it as a kid.

In fact, they never were. When we think of motion sickness, the picture that most often comes to mind may be that three-hour car trip to Grandma’s with a heaving child and no change of clothing.

Yet some adults are unpleasantly surprised to find themselves coming down with the unforgettably bad symptoms of queasy stomach, cold sweats, dizziness and headaches, even if they never got them as kids. From vision changes to pregnancy, a number of triggers can upset our finely tuned internal balance system and set sickness in motion, so to speak.

Here how it works: Humans use our eyes, ears and feet to estimate of our location and movement through space. You get a conflict when the signals disagree, which can happen to any of us if the conditions are bad enough.

“Let’s say your eyes are reading in the car, so they think you should be still, but the bouncing of the car tells your ears you’re moving,” says Timothy Hain, M.D., an otoneurologist and professor at Northwestern University Medical School.

Kids may be more prone to motion sickness simply because their ears work better; as we age we lose inner ear function, along with the tendency to hurl on a swaying boat.

Yet other hazards await adults. One often overlooked cause of persistent motion sickness may be a visual disorder -- also known as  “see-sick syndrome,” says Dan Fortenbacher, O.D., who treats the disorder at his practice in St. Joseph, MI. In these cases, an eye problem such as decreased depth perception or muscle control sends miscues to our vestibular system, a part of the inner ear and brain responsible for keeping us in balance as we go about our lives.

In many cases, patients have had vision issues since childhood, but age-related changes make it harder to compensate, Fortenbacher says.  It doesn’t take a car trip to set things off; patients may feel sick watching a movie, scanning the aisles while grocery shopping, even looking at stripes on a shirt.

“Sea sickness wasn’t an issue. My problem was being vertical. I would stand up and have to hold on because I would feel like the room was moving,” says LaReine Gretzky of Bridgman, Mich.

A stroke or bump to the head can also disturb the balance system. For Norman Greene, a television executive producer from New York, a head injury from a bad taxi accident at age 36 led to later miseries in any moving vehicle, particularly the helicopters he flies in to film.

“I discovered this when I took this little, baby roller coaster with my kid at Sesame Place. I had to sit down; I was horribly sick. I felt like I’d been tossed into a burlap bag and thrown off a bridge,” he says.

Inner ear problems like an infection or a circulatory problem can also affect the vestibular system. Seems reasonable, but experts are still puzzled as to why pregnancy and menstruation make women more prone to motion sickness.

Another double-whammy:  Migraine sufferers, who are more sensitive generally to external stimuli, are also about five times more likely to also suffer from motion sickness, Hain says. Peak ages for both maladies are parallel in females: Girls usually start getting migraines around age 12, when puberty kicks in.  There is another peak at age 35, then a second peak at age 52, around the time of menopause.

Treatment for see-sick syndrome involves eye exercises and special lenses.  For the rest of us, avoiding bumpy seats, a pre-trip heavy meal and reading can ward off the occasional travel queasiness.  And if you can, drive.

“Drivers have a big advantage in avoiding motion sickness.  Because they know where they are going, there are fewer surprise motions,” Hain says.

Do you suffer from motion sickness now -- even though you never did as a child? We'd love to hear from you. Leave a comment here or on Facebook; we may use your story in an upcoming msnbc.com post. 

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A Dutch woman recovering from a stroke had an unusual response to seeing her family:

The faces of her closest family members looked strange and distorted to her -- even repulsive.

But at the same time, strangers' faces seemed normal. In fact, she had much less trouble recognizing the faces of strangers and celebrities than she did her own flesh and blood.

This fascinating case of a 62-year-old woman referred to as JS is described in a recent issue of the journal Neurocase.

Hospitalized after having an ischemic stroke, JS was unable to recognize one of her daughters with whom she had regular contact. But she immediately recognized her other daughter, whom she hadn't seen in eight years.

When her grandchildren visited, she wouldn't let them sit on her lap because she thought they looked repulsive.

"Of course, JS felt bad and ashamed about not recognizing family members or perceiving them as ugly," says Dr. Joost Heutink, the lead author of the case study.

"As soon as we established that JS had a problem recognizing faces, we informed her family that a perceptual disorder prevented her from recognizing people she loved," he explains.

During neuropsychological testing, JS was given a facial recognition task. She was shown a series of photographs of her close family members, celebrities, and unfamiliar people and asked whether she recognized the person.

She correctly identified strangers 96 percent of the time and correctly identified a celebrity  -- whether it was Elvis, Albert Einstein, Oprah Winfrey, or Julia Roberts -- 76 percent of the time.

When shown photos of Osama bin Laden and Adolf Hitler, JS responded that these were pictures of "pathetic look-alikes who should have made more effort to look like the 'real' people." (They were the real people, though.)

While she found it easy to identify famous people and strangers, she had much more difficulty with her friends and family. She was the slowest and least accurate at placing familiar faces and correctly recognized them only 49% of the time.

When shown snapshots of her family, the facial proportions seemed distorted. She was even more critical of her grandkids' photos. To her, they appeared overweight and extremely tan.

"I have seen hundreds of cases with visual complaints after stroke in the posterior brain regions," says Heutink, an assistant professor of clinical neuropsychology at the University of Groningen in the Netherlands. "Several had problems recognizing familiar faces but I never encountered anything like this."

"It's an extremely rare case," he admits. As for why it occurred, Heutink and his colleagues write that "mild prosopometamorphopsia might explain this unusual clinical picture."

This mouthful of a word --  prosopometamorphopsia -- refers to a difficulty recognizing faces because they look contorted or warped in some way.

Heutink suspects that the areas of JS's brain damaged by stroke made it difficult for her to process and interpret information about facial identity along with its emotional context and meaning.

As a result, her facial distortions seem to be limited to close family and other emotionally relevant people in her life  -- perhaps explaining her reaction to seeing bin Laden and Hitler's photos.  She also has trouble recognizing basic emotional expressions on faces.

JS continues to have problems recognizing faces, but she has been taught how to compensate for it.  "We teach patients how to recognize people by specific details, such as their hair, clothes, voice, or posture," Heutink explains.

They also trained JS's family to call minutes before arriving at her home. That way she knows exactly who is there when the doorbell rings. It works every time. 

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NBC

Here's a scene from NBC's new show, "Awake," in which the protagonist, played by Jason Isaacs, experiences two alternate realities.

In the new TV series “Awake,” a detective, his wife, and son, suffer a severe car crash. The detective wakes up. But he seems to live in two realities: In one, his wife is dead and his son lives. In the other, his son is dead and his wife lives. Psychiatrists in each reality tell him the opposite existence is a dream. Yet clues from these parallel lives leak into crime investigations, helping the detective solve them.

Whoa.

But could any such thing happen in real life?

“My first suggestion is that the person who wrote this needs to get some counseling,” offered University of Florida neurologist Dr. Kenneth Heilman. 

That would be a “no.” But similar phenomenon do occur.

Heilman himself has a personal experience with something like it. When his mother was in the hospital after a severe heart attack that had restricted blood flow to her brain, she’d sometimes comment that she couldn’t tell if she was dreaming or was awake.

And he once had a patient with viral encephalitis, an inflammation of the brain, who said the same thing. Dreaming and waking life had become conflated.

Of course, all of us experience this phenomenon when we sleep and dream. In many, maybe most, dreams, we think what we’re experiencing is real because, as Heilman likes to describe it, we’ve engaged the clutch when sleeping and disconnected our reasoning, centered in the frontal cortices.

“That’s why, in the middle of a dream, you don’t think ‘OK, I can’t be hanging on to the top of a double decker bus feeling quite excited but not afraid as the bus charges around Edinburgh,” explained University of Cambridge professor Sue Llewellyn.

We also can have “lucid dreams,” those dreams that occur, often just before we wake, when our reasoning centers in the frontal lobes began to reengage. We’re asleep, and dreaming, but slightly aware. Also, drugs like LSD can induce hallucinations that blur the boundaries between dream and reality.   

Damage to the centers of reasoning and sensory input can create a variety of delusions. Reduplicative paramnesia, for example, was named in 1975 (though it was known as early as 1903) when a doctor realized that a few patients insisted, incorrectly, that the hospital was actually located at another location. Today it’s the insistence by suffers that places, people or events have been duplicated. Parkinson’s disease and strokes can cause the frontal brain lesions that lead to this syndrome, but so can severe trauma.

Like a car accident.  

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