Wednesday, May 16, 2012

11 Facts About the Ambidextrous

Image of guy writing with both hands via Shutterstock
1. If you can write equally well with either hand, then you are the one percent. Even among the small population of ‘multi-handed’ individuals, very few experience equal ease and skill with both hands. In comparison, around 10% of people are lefties.
2. Right-, left- and mixed-handedness aren’t sufficient to define the preferences of most people, according to experts. Most people experience some level of cross-dominance — favoring one hand for certain tasks, even if it’s the non-dominant one — and among the group of people who use both hands, there are even finer distinctions. Ambidextral refers to those who can use both hands as well as a right-hander’s right hand (so, really well), and ambisinistral can be used to describe people who use both hands as well as a right-hander’s left hand (that is, somewhat clumsily).
3. Unlike righties, who show strong left brain dominance, the hemispheres of ambidextrous and left-handed people’s brains are almost symmetric…
4. … as is the typical brain of a person with synesthesia, or “mixed senses,” who experiences cross-sensory perception. Among synesthetes, the instance of ambidexterity (and left-handedness) is much higher than in the general population.
5. The ambidextrous are more likely to possess the LRRTM1 gene (on chromosome 2), which is linked to schizophrenia. Studies reveal that people with schizophrenia are significantly more likely to be ambidextrous or left-handed than people who are not schizophrenic.
6. Another study, conducted through the BBC Science website, shows that of the one percent of 255,000 respondents who indicated equal ease writing with both hands, 9.2% of men and 15.6% of women reported being bisexual. In the same study, 4% of right-handed and 4.5% of left-handed men, and 6.2% of right-handed and 6.3% of left-handed women said they’re attracted to both sexes.
7. People who identify as ‘either-handed’ score slightly lower overall in general intelligence testing, and most often those scores are lower in arithmetic, memory and reasoning…
8. … except when they aren’t. A study of 8000 children ages 7 and 8 shows that the 87 mixed-handed students had more pronounced difficulties in language skills, and at ages 15 and 16, the same students showed a higher risk of ADHD symptoms and performed academically under both right- and left-handed students from the same sample.
9. Ambis can be quick to anger, according to a study from Merrimack College, which suggests a higher interlinking of brain hemispheres found in ambidextrous and lefties. A follow-up study found that the increased hemisphere connections correlate to increased awkwardness, clumsiness and moodiness.
10. But inconsistent-handers can also be easier to sway emotionally. Montclair State University tested a group of right- left and either-handers for emotional stability. Their findings report that of the group, righties were hardest to coerce, and ambis were most likely to report a change in mood based on their surroundings, directed thought, and music.
11. It’s not all bad news for the handedness-ambivalent, though. Being able to use both hands with (almost) equal ease can really pay off, especially in sports, arts and music. Some reportedly cross-dominant celebrities and historic figures include Leonardo da Vinci, Pete Rose, Richard Feynmen, pitcher Greg A. Harris, Michelle Kwan, Shigeru Miyamoto, Paul McCartney, Benjamin Franklin and Harry Truman.

Sunday, February 26, 2012

Chandra Bahadur Dangi is crowned world's shortest man at just 55cm tall

Stealing the title from Philippino Junrey Balawing who stood at 60cm (23.5 inches) at the age of 18 last year, Chandra Bahadur Dangi measured in at 54.6cm (21.5inches) when he was sized-up by the Guinness World Records team.

'The good news is that Chandra Bahadur Dangi is the world's shortest living man,' Guiness Records editor-in-chief Craig Glenday declared.

'If he is really 72 years old he is the oldest person to be awarded the shortest-man record,' he added.

Dangi, who is also the shortest person ever measured by the Guinness World Record team, is from a remote part of Nepal and said he was unaware of the world record title before a timber merchant who was visiting his village measured him last month.

'I am good. I feel happy. I want to travel around the world and spread the name of my country,' he said after taking a flight for the first time to meet record officials 267km away in the capital.

Dangi and his family have no idea when he stopped growing. His village lacks basic health care and Dangi - who has five brothers and two sisters of normal size - has never visited a doctor.

Before Balawing, Nepali man Khagnedra Thapa Magar held the title at 67cm (26.4 inches) tall.

Thursday, February 23, 2012

Dwarf Bullfighters – Human Exploitation Meets Animal Cruelty

It sounds cruel when I write about it, but watching a bunch of dwarfs running around with calves that match their size could invoke quite a bit of laughter. There’s nothing cute about this however, the fighting is quite real and dangerous. Thankfully, the calves and the men are usually unharmed.

Wondering what I’m talking about? Meet the bullfighting dwarfs of Mexico, a group of short entertainers who are by no means ashamed of what they do. The sport, for obvious reasons, has earned the title of being one of the most controversial in the world. Animal lovers say it’s cruel. Human rights activists agree. Critics worry about stereotyping. But there’s no denying the fact that it provides a steady means of income for those who otherwise would find it very difficult to get a job. Since employment discrimination is pretty widespread in Mexico, the dwarf community has actually benefited from the bullfighting shows. More often than not, the bullfighters are laughed at, and although this is the main purpose of their act, they would also like to be respected for what they do.
While bullfighting as a sport originated in Spain, the Mexican dwarf version is no less entertaining – a heady mix of comedy and excitement. Currently, about 20 dwarf bullfighting troupes exist in Mexico and they make frequent tours across the border to the US, performing for migrant native Mexicans. The competition between troupes is pretty intense, so many of them have added attractions to the show. A group from Guadalajara sings and does impressions, while the Bullfighting Dwarfs of Torreon jump through burning hoops.The tradition of the Mexican dwarf bullfighters started way back in the 1970s. According to the manager of the Giants of the Bullring, Gustavo Vazquez, the real goal of the show is to make people see past the fact that the performers are little people. Javier Landa, another performer, says that Americans may not understand what they do. “They may think we go out there to be laughed at, but that’s not the case. If a little person can fight a bull, he can do anything. That’s what we’re trying to prove.” The dwarf matadors can make up to $100 per show, and sometimes as little as $50.

China’s Kingdom Of The Dwarves

Over 100 height-challenged Chinese people perform in a show called Kingdom Of The Dwarves, close to Kunming, Yunnan Province.

Casting for the Kingdom Of The Dwarves show took place last summer, with only two conditions stipulated: the performers had to be between 18 and 40 years old and be shorter than 130 cm (4’3″). No other special skills were required. Now they take the stage of the Kunming World Butterflies Garden twice a day, singing, dancing and performing comedy sketches to entertain the crowds.

I know it looks like exploitation and discrimination, but the short performers see it only as another form of migrant labor and a haven away from people who mock and tease them on a daily basis. With discrimination and unemployment still high in China, the little people saw the Kingdom Of The Dwarves as an opportunity.

Just to clear things up, this is just a profitable theme park, not a community formed by the dwarves themselves as a shelter, and the mushroom houses only serve as decor and changing rooms, not as living quarters.

Saturday, December 24, 2011

A Drug That Wakes the Near Dead

The moment she saw him, Judy Cox knew her son was dead. It was an October morning in 2008, and she had just stepped out the door to run an errand when she found him lying faceup in the driveway, ghost white, covered in purple splotches. He wasn’t breathing, and when she couldn’t revive him, she ran screaming into the house where her husband, Wayne, was still asleep. “Chris is dead,” she cried. “Call 911!”

Wayne jumped out of bed and raced down to the driveway, where he knelt over his son’s limp frame and tried frantically to elicit a breath or a heartbeat. As he pumped Chris’s chest and scooped out the vomit that had collected in his mouth, Judy ran to the kitchen and steadied herself long enough to call for an ambulance.

Chris was 26. He had not been well. An A.T.V. accident the previous August left him with debilitating back pain that physical therapy did nothing to alleviate. His doctor had recently prescribed Oxycontin. His parents learned later that he had taken too much.

By the time the ambulance arrived, Chris’s heart had been still for at least 15 minutes. It took the paramedics another 15 to get it pumping again; even then, doctors had little hope he would survive. Brain cells begin dying off just five minutes after blood stops delivering oxygen. After 30 minutes, there is likely to be more dead tissue than living.

Nonetheless, the emergency-room staff members at the local hospital did their best. They hooked Chris up to a tangle of tubes and machines and injected him with drugs to stabilize his heart rate. Wayne and Judy watched helplessly from the hallway. After four hours, a doctor finally summoned them to a secluded corridor.

Chris was in a coma, the doctor said, and in all likelihood had suffered severe, irreversible brain damage. He was breathing only with the help of a ventilator and would probably have a series of heart attacks in the night.

“First they asked us to let them pull the plug,” Judy recalled one recent afternoon, as we sat in the living room of the Coxes’ house in a Memphis suburb. “Then they tried getting us to sign a do-not-resuscitate order.” Without one, the doctor explained, hospital staff would be forced to revive Chris each time he started slipping away, which could mean cracking his ribs and shocking him with electricity. Even if they managed to keep his body alive, what was left of his brain would surely die in the days ahead.

Wayne and Judy refused to sign. “This is not some dog we’re talking about putting down,” Wayne shouted. “This is our son.” Chris still lived with his parents. He was a good kid, a joker, but bashful, especially around girls. He liked playing basketball and fishing in the pond near his house. He was planning to take over the family repo business when Wayne retired in a few years. Before the A.T.V. accident, he’d never given them much trouble at all. He deserved every chance the hospital could give him.

The heart attacks never came. Four days later, Chris woke up.

It was not the awakening of Hollywood movies in which the patient comes to, just as he was, speaking full sentences and completely mobile. Three years later, Chris still cannot talk. Although he breathes on his own, his lungs battle a steady barrage of infections; a feeding tube provides all his sustenance, and his muscles have contracted into short, twisted knots. He can move only the slightest bit — his fingers and eyelids twitch, but his arms and legs remain mostly immobile — and his neck is not quite strong enough to hold up his head, which leans against a crescent-shaped support around his wheelchair headrest.

Still, Wayne and Judy say that his cognition is improving. On good days, they say, he can respond to basic commands — blink his eyes for yes, wiggle his finger for no, give a thumbs up when asked. Doctors agree that Chris has progressed beyond a vegetative state, to a hazy realm known as minimal consciousness. What that means — what it says about his experience of the world around him or his prospects for further recovery — is something they are still trying to figure out.

Convinced that the son they know and love is still “in there,” Chris’s parents have spent the past three years searching for a way to bring him back out. So far, their best hope has come from an unlikely source: Ambien. A growing body of case reports suggests that the popular sleep aid can have a profound — and paradoxical — effect on patients like Chris. Rather than put them to sleep, both Ambien and its generic twin, zolpidem, appear to awaken at least some of them. The early reports were so pronounced that until recently, doctors had a hard time believing them. Only now, more than a decade after the initial discovery, are they taking a closer look.

The first report of a zolpidem awakening came from South Africa, in 1999. A patient named Louis Viljoen, who, three years before, was declared vegetative after he was hit by a truck, had taken to clawing at his mattress during the night. Thinking he was suffering from insomnia, his family doctor suggested zolpidem to help him sleep. But 20 minutes after his mother ground the tablet up and fed it to him through a straw, Viljoen began to stir. His eyes, which normally wandered the room, vacant and unfocused, flickered with the light of consciousness. And then he began to talk (his first words were “Hello, Mummy”), and move (he could control his limbs and facial muscles). A few hours later he became unresponsive. But the next day, and for many days after that, zolpidem revived him, a few hours at a time.

Here was a case worthy of Hollywood: three years was well past the point at which doctors would expect any sort of spontaneous recovery. Viljoen awoke with the ability to speak in complete sentences. Not only did he recognize his mother, but he also recognized the voices of people who had spoken to him only when he was apparently vegetative. He remembered nothing of the mysterious realm he kept receding back into. When doctors asked him what it was like to slip away, he said he felt no changes at all. But he could recall conversations from the previous day’s awakening, along with bits and pieces of his former life: his favorite rugby team, specific matches he attended, players that he rooted for and against. As time passed, his cognition improved. He could laugh at jokes, and his awakenings stretched from a few hours to entire days. Eventually, he no longer needed zolpidem.

In the years that followed, a steady trickle of similar reports emerged — some from doctors who tried zolpidem after hearing about the Viljoen case, others from those who discovered its benefits accidentally, as Viljoen’s doctor had. The drug did not work for everyone, and even when it did, its effects typically wore off after an hour or two. But for a lucky few, those effects were profound. People who seemed vegetative for years were waking up.

There are roughly 200,000 patients in the United States trapped in the borderlands between consciousness and oblivion. Until recently, most doctors believed that recovering from this condition was not possible. Vegetative states were considered permanent after three months if the injury was caused by oxygen deprivation, or one year if it was caused by blunt trauma. And since minimally conscious patients did not fare much better than those who were vegetative, most doctors did not bother to draw the distinction.

But in the past decade, a series of developments have coalesced into a far more complicated picture than previously imagined. In 2003, an Arkansas man named Terry Wallis emerged, after 19 years, from a minimally conscious state. Neuroimaging suggested that his brain had essentially reconfigured itself — surviving neurons bypassed dead ones and forged new connections to one another. In a 2007 Nature paper, Nicholas Schiff, a neurologist from Weill Cornell Medical College, and his colleagues showed that deep brain stimulation — surgically implanting a “brain pacemaker” that sends electrical impulses to specific regions of the brain — can help some severely injured patients recover the ability to speak and eat, years after the injury. And just this month, Adrian Owen, a British neuroscientist, reported in the journal The Lancet that the brains of some patients who seemed vegetative responded to basic commands: their bodies didn’t move, but distinct patterns of neuronal firing were detected on EEG scans when these patients were told to make a fist (which triggered one region of the premotor cortex) or wiggle their toes (which triggered another).

This year, scientists at Moss Rehabilitation Research Institute and at the University of Pennsylvania, both in the Philadelphia area, began the first large-scale clinical study of zolpidem as a treatment for disorders of consciousness. (Amantadine, a drug used to treat Parkinson’s disease, and the anti-anxiety medication Ativan also show promise in increasing awareness in minimally conscious patients.) So far, the evidence suggests that less than 10 percent of brain-injured patients will experience the drug’s paradoxical effects, and that among those, only a few will respond as profoundly as Viljoen did. For families like the Coxes, such odds provide a tortured kind of hope. For doctors, they bring questions. Why does a sleeping pill induce awareness in some patients but not others? And what can these bizarre awakenings tell us about the brain’s ability to heal?

Two weeks after Chris first emerged from the coma, he began tracking objects with his eyes. At one month, he could follow simple commands. “His friends would come in the room, and there’d be two or three on each side of the bed,” Judy recalled. “And eventually, when they’d say, ‘Look at Jim,’ or ‘Look at Bob,’ he’d fix his eyes on the right guy.” Wayne and Judy asked for a follow-up M.R.I., but their neurologist said it would be pointless. Chris’s behaviors were entirely reflexive, he said; they were produced by his brainstem, which regulates basic functions like breathing and body temperature, not by his cortex, the region responsible for higher-order thinking. That Chris’s friends and family saw him following commands was proof of their denial, not of Chris’s recovery.

“Every couple days, the doc would stop in the doorway and shout Chris’s name to see if Chris responded,” Judy said. “But he wouldn’t come in the room and look at Chris up close. So one day, I practically grabbed his arm and dragged him into the room, over to Chris’s bed.” She told Chris to blink his eyes. He did. Then she made the doctor walk across the room and told Chris to keep his eyes on the doctor. He did. Finally, with the doctor standing across the room, eyes fixed on Chris, she asked Chris to give her a thumbs up. When he wiggled his thumb, just the tiniest bit, the doctor’s jaw dropped. Chris was not in a vegetative state after all. He was minimally conscious.

Still, there was little that the community hospital could do for him. It had neither the resources nor the expertise to tease out a prognosis or chart a course of therapy. The same was true of local nursing homes, which is where many patients like Chris end up.

So Wayne and Judy took over their son’s care, bringing him first to a premier brain-injury center in Atlanta (where Chris had a device implanted in his spine, which releases drugs to help with spasticity) and then to a clinic in Destin, Fla. (where he tried an experimental treatment known as hyperbaric oxygen therapy). They had just made their way back home to Tennessee when a friend told them about the Ambien paradox and the clinical trial in Philadelphia.

One hallmark of the minimally conscious state is a rapid fluctuation between levels of awareness. Spend 10 or 20 minutes with Chris Cox, and you might conclude that there is nothing going on upstairs. But spend a full hour, and at some point you’ll see his puppy-dog eyes come into focus. They will appear to search for one of his parents, or to settle quizzically on the new person in the room. Ask him to say something, and he’ll smack his lips frantically before leaning forward and tapping his feet in apparent frustration. You’ll swear that he is there with you and that only his physical infirmities (he cannot quite swallow or control his jaw) prevent him from describing the netherworld from which he has just emerged.

And then, a few minutes later, he’ll slip away again.

This fluidity makes diagnosis a challenge. “If a patient follows every command you give them, you know that,” says Dr. John Whyte, director of the Moss Institute and lead investigator on the zolpidem trial. “If a patient has never, ever followed a command, you know that too. But if you tell a patient to wiggle their finger, and they do it occasionally — which is the case for most of these folks — how do you figure out if that ‘occasionally’ means something or not?”

Whyte has spent his entire career trying to answer this question. His first job after his residency was at a facility with a large number of vegetative patients. While working there, he was struck by the amount of contention over diagnoses. For all their experience with this population, clinicians could not seem to agree on whether any given patient was actually conscious. Family members also argued, with one another and with staff, over the meaning of every wince, twitch and eye flutter.

It turned out that a lot of people — staff members included — were drawing their conclusions from pure coincidence. Whyte told me about one mother who insisted that her son would point down toward his feeding tube to indicate that fluid was leaking onto his stomach, causing irritation. “He did it while I was there,” Whyte says. “And she lifted his shirt and said: ‘See, doctor, there’s the liquid. He’s communicating with us.’ And I said: ‘How often do you look under there when he isn’t pointing like this? Never? Not even once?’ ” It was possible that the pointing corresponded to the leak, Whyte explained. But it was also possible that the leaking was constant and the pointing was random. There were countless other examples. “Behaviors would be exceptions if they happened at the wrong time, and evidence if they happened at the right time,” Whyte says.

To help eliminate this bias, Whyte developed what he calls the single-subject assessment, in which doctors design a set of tests specific to each patient’s idiosyncrasies to determine whether the patient is vegetative or minimally conscious. It is painstaking work, but the information it yields is significant. “Patients who achieve minimal consciousness early tend to have a better prognosis,” Whyte says. “And you can at least try to build a communication system with them, because you have a foundation to work from.”

With a reliable assessment method in place, he began searching for ways to build on that foundation. Then the curious Ambien awakenings caught his attention.

It’s not entirely surprising that Ambien would arouse instead of sedate. The pill has long been linked to reports of bizarre sleepwalking behavior (not to mention sleepeating, sleeptalking, even sleepdriving). Some scientists call this phenomenon “paradoxical excitation.” So far, none of the accepted determinants of prognosis — age, overall health, the nature of the initial injury or the extent of brain damage as determined by an M.R.I. — have proved useful in predicting which brain-injured patients will experience it and which won’t. To begin answering that question, Whyte says, you need to study both responders and nonresponders in an unmedicated state.

One morning this past March, I met Chris, Wayne and Judy at the University of Pennsylvania’s main hospital, where they had been flown in from Tennessee, at the study’s expense, so that Chris could be tested in an unmedicated state. From the corner of a small hospital room, we watched as Whyte’s research assistant, Andras Szeles, attached dozens of tiny electrodes to Chris’s face and scalp, then fitted him with a large headset. The electrodes would measure Chris’s brain activity as Szeles administered a series of cognitive tests.

For one test, Szeles placed a rubber glove on Chris’s right hand. A voice coming through the headset told Chris to either “squeeze glove” or “squeeze bare,” several times over. Chris did not seem to be responding at all, but Szeles explained that the electrodes would measure what the naked eye could not. “We’re not so interested in whether or not Chris can squeeze,” he said. “We just want to know if he’s trying to squeeze.” Different neurons fire when you move your left hand versus your right hand. They also fire if you imagine moving it, prepare to move it or start to move it but stop, all of which the electrodes would detect.

“The term ‘consciousness’ can be a real can of worms,” Szeles said. “There are degrees of awareness, and it’s not always clear what the threshold should be. What we’re really looking for here is evidence of comprehension and will.” If Chris understood the words “squeeze” and “glove,” knew that this very specific thing was being asked of him, and possessed, at the most basic level, the will to respond, a distinct pattern of brain waves would show up in the results.

After Whyte and his team have tested 80 patients, they will compare the results of zolpidem responders to those of nonresponders and look for clues that might help explain the difference — maybe a specific brain region that lights up unexpectedly, or a pattern of neuronal firing common to one group but not the other. Any such discovery could light a path not only through the labyrinths of Chris’s fractured mind but to a better understanding of consciousness itself.

Wayne and Judy have a more immediate question: they want to know their son’s long-term prognosis. Has he reached the pinnacle of his cognitive recovery? Or is it a launching pad from which greater heights might be reached?

“Once a patient progresses to minimal consciousness, we can’t predict what’s going to happen,” says Dr. Joseph J. Fins, chief of medical ethics at Weill Cornell Medical College and author of a coming book, “Rights Come to Mind: Brain Injury, Ethics and the Struggle for Consciousness.” Some patients have recovered full consciousness, but many more remain stuck in limbo. The only way to know the outcome is to give the patient time.

But offering time is a complex proposition. “Early on, when families have the option to pull the plug, it’s almost impossible to tell what the long-term prognosis will be,” says Dr. Soojin Park, a neurointensivist at the University of Pennsylvania Hospital, and an investigator on the zolpidem trial. “And then later, when we have the certainty — that this is as good as it’s going to get — that option is gone. Because by then, the patient is breathing on their own. There’s no more plug to pull.” At that point, families who want to end a loved one’s suffering must either have the feeding tube removed, or agree to let the next bacterial infection win out, unhindered by antibiotics. Many families find choosing these deaths much more difficult than turning off a ventilator. It’s an instinct reinforced by religious edicts that forbid the withholding of basic sustenance but allow, for example, unplugging artificial respirators.

It is not uncommon for doctors to assume the worst and advise family members to withdraw care early. They do so in part because they see their duty as helping loved ones face reality. But Fins argues that this is a cop-out. “It’s glossing over all the unknowns for the sake of a quicker, cleaner solution,” he says. “It’s wrong to be so uniformly fatalistic so early on, especially with all the data emerging about the prospects for later-stage recovery.”

According to several studies, about 40 percent of patients who have been declared vegetative are actually minimally conscious. Other studies have shown that a surprising number of vegetative and minimally conscious patients made huge strides toward recovery much later than conventional wisdom would predict.

Park says that more doctors are trying drug therapy on vegetative and minimally conscious patients, but for the most part, they are groping in the dark. “We still don’t understand which drugs should work on which patients, or at what dosage, or at what point in their recovery,” she says. “And that makes it tough for families to know when they should fight and when they should give up.”

There is also the matter of cost. Treating and monitoring patients like Chris — designing and performing single-subject assessments that can discern random twitches from deliberate behavior, managing the host of medical complications that can stymie brain recovery and continually evaluating progress — is significantly more expensive than placing them in nursing homes, where they receive basic care but have no access to brain-injury specialists. Proponents argue that the measures will save money in the long run — if the patient is able to go home, for instance. Still, it’s unclear whether even the most aggressive care will make much difference for many patients. “The payers need a better sense of what the likely outcome is for any given patient,” says Tom Smith, program director at Moss, “so that they can say with confidence which patients are likely to benefit from treatment, and how significant that benefit is likely to be. And I hate to sound this way, but then it’s basically: ‘Am I going to invest this amount of money to get this outcome? Is that worth it?’ And that is a tough, tough question to answer.”

When Chris first returned from the hospital, the Coxes’ house was flooded with well-wishers. A former teacher brought a quilt that Chris and his classmates made in grade school. Old girlfriends, acquaintances and childhood pals visited regularly. His high-school friends even held a fund-raiser to help pay for some of his therapy. But as time wore on, and it became clear that he would neither die nor fully recover, the guests dwindled. Besides Chris’s sister, Amber, who visits often, Wayne and Judy are now mostly on their own.

The couple surrendered their bedroom, which is on the ground floor of their split-level house, to Chris. They take turns sleeping there, on a small cot in the corner of the room, surrounded by medical equipment: a hospital bed with a queen-size air mattress that helps prevent bed sores, a special chair called a “sit-stand,” which can be cranked into an upright position and is supposed to help ease muscle contractions. A mechanical lift. A breathing machine.

Judy is especially keen to show me Chris’s latest gadget, a device called an Eyegaze, that looks a bit like an iPad, and which Chris is learning to use to communicate. She mounts it to a handlebar on Chris’s wheelchair. At first, Chris’s eyes move rapidly across several rows of icons — words with pictures, partial sentences like “I want” or “I like,” and cartoon images of friends and family members with their names in bold. Tracking his eyes, the computer reads: “Green. Brit. I want.” And then, “Brit–Brit–Brit–Brit–Brit.” Brit is his cousin. It’s unclear if he’s asking for her, or if his eyes are just not cooperating.

Judy puts the computer away. He still needs practice, she says. When they first tried it, in February, during outpatient rehab, the therapist asked Chris what color went with Valentine’s Day, and he was able to look at the “red” icon. But so far, “I want a drink,” is the only full sentence he has managed.

Each day begins with the same routine: Judy helps Chris up, forcing him to sit on the edge of the bed, without neck or back support, for several minutes. The goal is to strengthen his neck muscles so that one day he can hold his own head up. A nurse helps her bathe him and then lift him into his chair, so that he can be wheeled into the living room or taken outside. Three times a week, a van delivers mother and son to a rehab center, where a therapist works to stretch and stimulate Chris’s contracted muscles. And almost as often, either Wayne or Judy spends several hours on the phone, battling Chris’s insurance company, which they say has covered private nursing and weekly therapy but denied an extended stay at a brain-injury rehab center. The couple arrange their schedules so that their son is never without at least one parent.

The Coxes have surrounded themselves with a new group of friends — other parents with children like Chris. The families in this informal group share strategies and trade information on emerging research and experimental treatments. They also talk of weariness and isolation. “At the end of the day, you feel like you’re a thousand years old,” Judy says. “And you have no idea how you’re going to get up and do it all over again tomorrow.” Both Wayne and Judy admit to being frustrated by the slow pace of Chris’s progress. But he’s come this far; they can’t help hoping that he might come further still. “I know that some people, even people who loved Chris, think maybe he should have just died,” Wayne says. “But he didn’t die. He lived. And as long as he’s still breathing, we have to do the absolute best we can for him.”

The reports on zolpidem are still mixed. Viljoen and a few others have improved steadily over time; some of them are now fully conscious on their own, without medication. (Viljoen is confined to a wheelchair and has cognitive disabilities but has improved over the years.) But such improvement is rare. According to Whyte, most responders fall into one of two categories: those who can take zolpidem daily, with no appreciable loss of efficacy, and those for whom the “awakenings” wane with continued use. The latter type, he says, may be the most common.

With no way of knowing which type of responder Chris might be, the Coxes play it safe. They give Chris Ativan every day; it has a similar though less profound effect on his behavior. But zolpidem they hoard like pixie dust, giving it only on special occasions, when friends and family can be there.

They gave him some when I visited, so I could see how it works.

A few minutes after receiving the zolpidem, Chris opened his eyes and smiled. Judy sat on the bed, facing him. “Hey, buddy!” she said. “Can I have a kiss?” She leaned in, cheekward, but he turned his head up in what looked like a deliberate slight. “Chris!” she admonished, playfully. He smiled and grunted. He was teasing her. Just as she pulled away, he thrust forward and grazed her cheek with puckered lips. Confident that he was there with us, Judy took out a marker and some paper and wrote one command after another, each of which Chris followed: Stick out your tongue, give me five, give me a thumbs up. And then, “Show us your Elvis grin.” Chris curled his upper lip into a sneer. When Judy ran out of commands, Chris began smacking his lips and moving his tongue. “Talk to us, buddy,” Wayne said. “Say, ‘Mom,’ ” Judy said. After several moments, Chris managed a loud, slow “Maaaa.”

Monday, December 12, 2011

Advertise on Could Conjoined Twins Share a Mind?

May 25, 2011
Could Conjoined Twins Share a Mind?

It was bedtime for Krista and Tatiana Hogan, and the 4-year-old twin girls were doing what 4-year-olds everywhere do at bedtime. They were stalling, angling for more time awake. Their grandmother, Louise McKay, who lives with the girls and their parents in Vernon, a small city in British Columbia, was speaking to them in soothing tones, but the girls resorted to sleep-deferring classics of the toddler repertory. “I want one more hug!” Krista said to their grandmother, and then a few minutes later, they both called out to her, in unison, “I miss you!”

But in the dim light of their room, a night light casting faint, glowing stars and a moon on the ceiling, the girls also showed bedtime behavior that seemed distinctly theirs. The twins, who sleep in one specially built, oversize crib, lay on their stomachs, their bottoms in the air, looking at an open picture book on the mattress. Slowly and silently, in one synchronized movement, they pushed it under a blanket, then pulled it out again, then back under, over and over, seeming to mesmerize each other with the rhythm.

Suddenly the girls sat up again, with renewed energy, and Krista reached for a cup with a straw in the corner of the crib. “I am drinking really, really, really, really fast,” she announced and started to power-slurp her juice, her face screwed up with the effort. Tatiana was, as always, sitting beside her but not looking at her, and suddenly her eyes went wide. She put her hand right below her sternum, and then she uttered one small word that suggested a world of possibility: “Whoa!”

In any other set of twins, the natural conclusion about the two events — Krista’s drinking, Tatiana’s reaction — would be that they were coincidental: a gulp, a twinge, random simultaneous happenstance. But Krista and Tatiana are not like most other sets of twins. They are connected at their heads, where their skulls merge under a mass of shaggy brown bangs. The girls run and play and go down their backyard slide, but whatever they do, they do together, their heads forever inclined toward each other’s, their neck muscles strong and sinuous from a never-ending workout.

Twins joined at the head — the medical term is craniopagus — are one in 2.5 million, of which only a fraction survive. The way the girls’ brains formed beneath the surface of their fused skulls, however, makes them beyond rare: their neural anatomy is unique, at least in the annals of recorded scientific literature. Their brain images reveal what looks like an attenuated line stretching between the two organs, a piece of anatomy their neurosurgeon, Douglas Cochrane of British Columbia Children’s Hospital, has called a thalamic bridge, because he believes it links the thalamus of one girl to the thalamus of her sister. The thalamus is a kind of switchboard, a two-lobed organ that filters most sensory input and has long been thought to be essential in the neural loops that create consciousness. Because the thalamus functions as a relay station, the girls’ doctors believe it is entirely possible that the sensory input that one girl receives could somehow cross that bridge into the brain of the other. One girl drinks, another girl feels it.

What actually happens in moments like the one I witnessed is, at this point, theoretical guesswork of the most fascinating order. No controlled studies have been done; because the girls are so young and because of the challenges involved in studying two conjoined heads, all the advanced imaging technology available has not yet been applied to their brains. Brain imaging is inscrutable enough that numerous neuroscientists, after seeing only one image of hundreds, were reluctant to confirm the specific neuro­anatomy that Cochrane described; but many were inclined to believe, based on that one image, that the brains were most likely connected by a live wire that could allow for some connection of a nature previously unknown. A mere glimpse of that attenuated line between the two brains reduced accomplished neurologists to sputtering incredulities. “OMG!!” Todd Feinberg, a professor of clinical psychiatry and neurology at Albert Einstein College of Medicine, wrote in an e-mail. “Absolutely fantastic. Unbelievable. Unprecedented as far as I know.” A neuroscientist in Kelowna, a city in British Columbia near Vernon, described their case as “ridiculously compelling.” Juliette Hukin, their pediatric neurologist at BC Children’s Hospital, who sees them about once a year, described their brain structure as “mind-blowing.”

An incomparable resource for neuroscientists interested in tracing neural pathways, in the malleability of the brain and in the construction of the self, Tatiana and Krista are also a study in the more expansive neural system of sociology: the feedback loop of how their family responds to difference, how the world outside the walls of their home responds to the family’s response and how the girls respond in turn. For now, for the most part, the girls are not treated as if they were, as one neuroscientist described them, “a new life form.” Although they rarely venture outside their home, they spend most days the way many preschoolers do, chasing after an uncle’s puppy or watching “Dora the Explorer” or testing their grandmother’s considerable patience as they play their private games at bedtime.

“Now I do it,” Tatiana said, reaching for the cup from which her sister was just drinking. She started to chug. Krista’s hand flew to her own stomach. “Whoa!” she said. The girls cracked up. Louise sighed. “Girls,” she said one more time. “It is time to settle down.”

When Felicia Simms found out about the unusual nature of her pregnancy, she was 20 years old with two small children, living on her own in a small apartment and relying on the Canadian welfare system for financial support. She still had an on-again, off-again relationship with the father of her first child, her high-school sweetheart, Brendan Hogan, but they often fought about his drinking and drug use, and he worked only sporadically, in construction or at a meatpacking plant. There are probably no two parents who would feel prepared to cope with such life-altering news, but Simms and Hogan did not have the benefit of significant resources to help them.

The evening after her first prenatal checkup, Simms, who had just learned she was having twins, got a call from her doctor, asking her to come back the next day. Concerned, she brought along her mother, Louise, and a sister-in-law. There was no easy way to say this, the doctor said: the twins were conjoined. The room went silent. Then all three women wept. Simms has little recollection about what was going through her mind at that moment. She was not without a reference point: both Simms and her mother had been fascinated by documentaries about Lori and Reba Schappell, two sharp, functional women who are, at age 49, the oldest living female craniopagus twins in the United States. “I was just trying to process it,” Simms said.

The obstetrician informed her that one of her options was to terminate the pregnancy.“I didn’t even consider it,” Simms said, sitting at the dining-room table of her home in Vernon, a popular ski-resort town set in a region of British Columbia known for its emerald green lake and stunning mountain views. “I think I have a lot more respect for nature than a lot of other people.”

Now 25, Simms is a mother of five children: Rosa, 8; Christopher, 6; Tatiana and Krista; and Shaylee, who is 3, born a year and a half after the twins. They live together with their maternal grandparents, three cousins, an aunt and uncle and Hogan, who moved in with the family last year. When I met them, they resided in a tract house that had been subdivided into many rooms for senior living before the Hogan-McKay clan arrived. The family relies mostly on public assistance. Dinner sometimes seems to make it on the table only by some last-minute stroke of luck or resourcefulness.

Simms has always appreciated what she characterizes as her mother’s easygoing ways. It was Louise who paid for her first facial piercing, at age 12, and who accepted the news easily when she learned her daughter was pregnant three years later. “We were never normal,” Simms says, and “that was O.K.” She thinks that in some ways it was easier for her family to accept the idea of conjoined twins than it might have been for a family that was more conventional. They did not have to reinvent their sense of themselves, the image they presented to the world. “In my house growing up, everything didn’t have to be perfect,” she said. “I never had to be like everybody else, look like everybody else.”

Unless the twins are having a rare health crisis or are being followed by video cameras (the National Geographic Channel showed a documentary about them last year), they are part of the general background din of the house and a far less dominant issue than the pressing financial concerns. The adults of the family tend to congregate around the long dining-room table, where the girls’ grandmother runs both a delivery business and the household — directing drivers, calling out to the twins to stop teasing their little sister and planning dinner for everyone.

Simms has the same coloring and smoky eye makeup of the actress Kristen Stewart, and the movie “Twilight” plays in heavy rotation at their home. A fascination with the supernatural seemed to inform even how she thought about her unusual pregnancy. “A month before they were born, I had a dream of them being born that was completely the way it happened,” Simms said, sitting at the dining-room table. “I heard them crying in my dream just like they cried when they were born. I just knew they were going to be fine.”

By the time she delivered, the doctors were preparing her for the worst; social workers met with her about grief counseling. But Simms’s intuition was right: the twins were born healthy at 34 weeks, miraculously stable and in need of no major interventions. The girls stayed under observation at the hospital for two months, and soon Simms and Hogan faced another major decision — whether or not to separate them.

Cochrane, their neurosurgeon, consulted with other surgeons who have separated conjoined craniopagus twins, and the team concluded, based on their experience with that kind of surgery and their analysis of the CT scans, that separation would be extremely high risk.

“You’d have to have cut through too much normal tissue and split the thalami,” said James T. Goodrich, director of pediatric neuro­surgery for Children’s Hospital at Montefiore in the Bronx who was consulted on the case. “It would have potentially been lethal.”

Goodrich knows from experience how unpredictable and potentially dangerous any separation of craniopagus twins is likely to be. Beginning in 2003, he performed a series of operations to separate Clarence and Carl Aguirre, craniopagus conjoined twins who were 18 months old during the first operation. Although Goodrich proclaimed their futures bright at the time of the separation, and one of the two boys is indeed thriving, his brother eventually developed debilitating seizures; the boy, now 9, takes medication that impairs his alertness and cognition.

In the case of the Aguirre brothers, neither boy would likely have survived without the surgery, because the layout of their vascular systems put too much pressure on Clarence’s heart. In the case of Tatiana and Krista, however, Goodrich said, “Mother Nature, or whoever their God is, did not give them the other issues that are the problem with these kids — cardiac failure.” Although Tatiana does bear more of the burden of pumping blood for their two bodies, the vascular system is symmetrical enough that the doctors consider them relatively healthy. (Given the risks, the family opted not to separate the girls.)

From the very beginning, doctors wondered if the twins shared sensation; an early video shows one girl being pricked for a blood test as the other starts to cry, her face a perfect mirror image of her sister’s. A pacifier in one mouth seemed to soothe both crying babies.

Despite the interest of the scientific community, the girls, because of their age, have not experienced extensive investigation. “If one of them needs it for their health, by all means, they can do what they need to do,” said their step-grandfather, Doug McKay, who, like their grandmother, is very involved in the girls’ care. “But I’ll be damned if you’re going to poke and prod and experiment on them.”

Cochrane gives the family credit for being “able to play the hand they’ve been dealt . . . and to recognize that these kids are growing and developing. And that they’re not that different from normal kids.”

‘I have two pieces of paper,” Krista announced. The girls sat at a small table in the living room, drawing, their faces, as always, angled away from each other. Each had one piece of paper. So I was surprised by Krista’s certainty: She had two pieces of paper? “Yeah,” the girls affirmed in their frequent singsong unison, nodding together. It was one of those moments that a neurologist or psychologist or any curious observer could spend hours contemplating. Was Krista using “I” to refer to both her and her sister? Is Tatiana agreeing with her sister’s assessment at a cognitive level or uttering the same word simultaneously for reasons unknown to her?

Although the girls can run, play peekaboo, engage in finger play shoot’em-ups for 20-minute marathons and covet their older sister’s Zhu Zhu pets, they are both also developmentally delayed by about one year. Their delays do not surprise their doctors, given their unusual brains and the fact that the girls have been forced to develop skills other children have not.

A crayon drops to the floor, and I move to pick it up, imagining how laborious it would be for them to move away from the table as one, with Tatiana leaning awkwardly to allow her sister to crouch to the ground. When I reach for it, however, the crayon is not there. It is already in Krista’s hand, as if by magic. “My foot do it!” she tells me. Neither girl could draw the letter X, but if there were a standardized test for grasping with toes, the Hogan twins would surely come up in the 99th percentile.

The girls’ brains are so unusually formed that doctors could not predict what their development would be like: each girl has an unusually short corpus callosum, the neural band that allows the brain’s two cerebral hemispheres to communicate, and in each girl, the two cerebral hemispheres also differ in size, with Tatiana’s left sphere and Krista’s right significantly smaller than is typical. “The asymmetry raises intriguing questions about whether one can compensate for the other because of the brain bridge,” said Partha Mitra, a neuroscientist at Cold Spring Harbor Laboratory, who studies brain architecture. The girls’ cognition may also be facing specific challenges that no others have experienced: some kind of confusing crosstalk that would require additional energy to filter and process. In addition to sorting out the usual sensory experiences of the world, the girls’ brains, their doctors believe, have been forced to adapt to sensations originating with the organs and body parts of someone else.

As fantastic as it sounds, there is little doubt in Cochrane’s mind that the girls share some sensory impressions. When they were 2 years old, he performed a study in which Krista’s eyes were covered and electrodes were glued to her scalp. While a strobe light flashed in Tatiana’s eyes, Krista was emitting a strong electric response from the occipital lobe, which is where images are assembled. The test also worked when the girls switched roles. The results were not published, and some neuroscientists believe that this kind of test, which measures changes in brain activity beneath the skull, is imprecise in determining what region of the brain is at play; but most would agree that any response in the other twin’s brain suggests, at a minimum, connectivity.

The explanation Cochrane proposes is surprisingly straightforward for so unusual an outcome: that visual input comes in through the retinas of one girl, reaches her thalamus, then takes two different courses, like electricity traveling along a wire that splits in two. In the girl who is looking at the strobe or a stuffed animal in her crib, the visual input continues on its usual pathways, one of which ends up in the visual cortex. In the case of the other girl, the visual stimulus would reach her thalamus via the thalamic bridge, and then travel up her own visual neural circuitry, ending up in the sophisticated processing centers of her own visual cortex. Now she has seen it, probably milliseconds after her sister has.

The results of the test did not surprise the family, who had long suspected that even when one girl’s vision was angled away from the television, she was laughing at the images flashing in front of her sister’s eyes. The sensory exchange, they believe, extends to the girls’ taste buds: Krista likes ketchup, and Tatiana does not, something the family discovered when Tatiana tried to scrape the condiment off her own tongue, even when she was not eating it.

Even knowing about the tests and what Cochrane believed, I listened to the family’s stories with some amount of skepticism. Perhaps they were imagining it or exaggerating for the sake of a good story. Then in one of the many idle moments of the five days I spent with the family, the girls were watching television, and I absent-mindedly gave Tatiana’s foot, which Krista could not see, a little tickle. She turned to me and smiled, and then Krista spoke: “Now do me,” she said. Had she felt the sensation but wanted the emotional experience of knowing that she, too, was receiving that kind of playful attention?

On another day, Simms picked up a thermometer that had been left on the kitchen table and, just for fun, placed it in Krista’s mouth. Almost immediately, Tatiana got a distant look in her eyes. “Not in mouth,” she said, sounding angry. Then she was quiet, and her focus seemed to tack hard. Her tongue, visible in her half-open mouth, was moving in an unusual way, curling. I wondered if I was imagining something. But Rosa, her 8-year-old sister, noticed it, too.

“Isn’t that weird?” she said, her own blue-green eyes wide. “Did you see? The way her tongue was curled? It was in Krista’s mouth, but Tatty’s tongue was doing that.”

Rosa paused for a moment, thinking about the imaginary thermometer, then changed the subject to tell me about the part she had in a school show, playing “the nerd sheep.” Just once, could a visitor’s attention be directed at her own extraordinary role in the world?

At first, the sight of their younger sister, Shaylee, walking freely past the girls, struck me as painful, a constant reminder of their own constraints, her liberty a moment-by-moment assertion of superiority. But over time, my sympathies switched: the twins’ unity was so strong I wondered if Shaylee felt she was somehow missing an essential part of herself. When the girls wanted to wash their hands in the sink, they worked as one, silently, to drag the bench over to the bathroom. More often than not, they both seemed to want to slither like snakes at the same moment, to roll a ball down a ramp to the television room, to drift toward the electric piano. But acceptance, rather than mutual desire, might be at play: the family often reminds them they have no choice but to compromise, and Simms believes they have a private logic for determining whose turn it is to decide their whereabouts.

In the Hogan-McKay family, the fantasy of twinship, of a loving double, runs strong. Simms insists that her daughter Shaylee is her perfect replica, identical in face and temperament — she calls her “my mini-me.” The girls’ older sister, the tiny, round-faced Rosa, told me that she and her cousin Shyann, who lives with her, “are like twins” — despite the fact that Shyann is much taller and a year older. And Christopher, a winsome 6-year-old with a Mohawk that matches his father’s, has been told that he had a twin who died in the womb. The remnants of the twin, the doctors told his mother, were absorbed into his body, leaving only an unusual hairy patch on his back that still remains, the soft fuzzy shadow of a life that might have been. “If I don’t feel like being me, I can switch to how my twin feels,” Christopher told me once, as he was playing a video game. “And if I’m mad, I can switch to how my twin feels. Then I can switch back to being me.”

Tatiana and Krista represent even more of a unity than the closest identical twins, and in a house where everyone’s attention is divided, the girls always have each other. Simms is the first to acknowledge that her relationship with the twins is different from those she has with her other children. “Rosa was my firstborn, so that’s always special,” she said, “and Christopher’s the only boy. And Shaylee, she’s my baby.” The twins, she says, are really “Nana’s girls,” partly because they bonded with their grandmother when Simms was going through her difficult pregnancy with Shaylee. If some other, more painful distinction is at play — a rejection of their difference or a sense of burden — that response is not apparent.

Though they frequently move in near synchrony, mirroring each other’s gestures, the girls clearly have different personalities. Simms says Tatiana is more lighthearted, that Krista is “more of the bully” — that she is moved to scratch or hit Tatiana in frustration more often than the reverse. And they look remarkably different, although they are thought to be identical. Tatiana’s heart and kidneys do more of the work for their bodies than Krista’s do, so she is smaller than her sister, frailer, diminutive like her fairy namesake; Krista has the round belly and cheeks of many a preschooler. Krista has a small dot of a red birthmark on her chest; Tatiana does not. Krista is allergic to canned corn; Tatiana is not. Even twinship, shared daily experiences and possibly shared sensory experiences do not render them one and the same.

When the girls were younger, they used to try to pull their heads away from each other, Simms told me. “And I would say to them, ‘You can’t do that,’ ” she said. “I just told them: ‘You girls are stuck. You’re stuck together.’ ” Sometimes the girls would offer up that information themselves. “I am stuck,” Krista told me one afternoon, pausing as she and her sister made their way back to the bathroom, where they wanted to play with the faucets. She tapped the portion of the head that she shares with her sister. And does she like being stuck? “I love I am stuck,” she said. She smiled. She had the dreamy look of someone romantically infatuated. “I love my lovely sissy,” she said. Later that day, Tatiana announced the same thing, but she sounded more distressed, confused: “I am stuck,” she said, a querulous look on her face. She was a girl sending a message in a bottle, or from a bottle, searching for some answer to the essential question of her mysterious, still-forming mind.

Later in the week, Simms was getting Tatiana and Krista dressed for a five-hour van ride on treacherous roads in the snow to Vancouver, where the girls had a series of doctors’ appointments. This time there was no fighting over the two different sweatshirts. On the rare occasions when the girls do fight, it’s painful to watch: they reach their fingers into each other’s mouths and eyes, scratching, slapping, hands simultaneously flying to their own cheeks to soothe the pain.

That morning, even though Krista grabbed initially at the pink hooded sweatshirt, she ceded it easily to Tatiana, and Krista settled for the gray. “I am in gray,” she said. “And I am in pink,” Tatiana said. Something about the clear distinction may have rung some bell in Krista’s mind. She looked at her mother. “I am just me,” she said. The sentiment — assertive and profound — was hardly out of her mouth before her sister echoed her. “I am just me,” Tatiana said.

The girls surely have a complicated conception of what they mean by “me.” If one girl sees an object with her eyes and the other sees it via that thalamic link, are they having a shared experience? If the two girls are unique individuals, then each girl’s experience of that stimulus would inevitably be different; they would be having a parallel experience, but not one they experienced in some kind of commingling of consciousness. But do they think of themselves as one when they speak in unison, as they often do, if only in short phrases? When their voices joined together, I sometimes felt a shift — to me, they became one complicated being who happened to have two sets of vocal cords, no less plausible a concept than each of us having two eyes. Then, just as quickly, the girls’ distinct minds would make their respective presences felt: Tatiana smiled at me while her sister fixated on the television, or Krista alone responded with a “Yeah?” to the call of her name.

Although each girl often used “I” when she spoke, I never heard either say “we,” for all their collaboration. It was as if even they seemed confused by how to think of themselves, with the right language perhaps eluding them at this stage of development, under these unusual circumstances — or maybe not existing at all. “It’s like they are one and two people at the same time,” said Feinberg, the professor of psychiatry and neurology at Albert Einstein College of Medicine. What pronoun captures that?

The average person tends to fall back on the Enlightenment notion of the self — one mind, with privacy of thought and sensory experience — as a key characteristic of identity. That very impermeability is part of what makes the concept of the mind so challenging to researchers studying how it works, the neuroscientist and philosopher Antonio Damasio says in his book, “Self Comes to Mind.” “The fact that no one sees the minds of others, conscious or not, is especially mysterious,” he writes. We may be capable of guessing what others think, “but we cannot observe their minds, and only we ourselves can observe ours, from the inside, and through a rather narrow window.”

And yet here are two girls who can possibly — humbly, daily — feel what the other feels. Even that extraordinary dynamic would still put the girls on the continuum of connectivity that exists between ordinary humans. Some researchers believe that when we observe another person feeling, say, the prick of a pin, our neurons fire in a way that directly mimics the neurons firing in the person whom the pin actually pricks. So-called mirror neurons are thought to foster empathy, creating connections of which we are hardly aware but that bind us in some kind of mutual understanding at a neurological level.

Could the girls’ connection go beyond sensory impressions to higher thoughts, thoughts as simple as “I want water” or as complex as “I’m tired of ‘Good Night Moon’ ”? The family says that the girls often get up silently and suddenly and walk over to, say, a sippy cup, which Tatiana then immediately hands to Krista, who drinks from it. I did not witness any such incident; but if it happens as described, does one girl silently express her thirst to the other in the form of a higher thought? Does Tatiana somehow experience, instead, her sister’s basic sensation of thirst, but recognize it as originating elsewhere? Is the request whispered, inaudible or incomprehensible to anyone but the sister who is so closely linked?

The story of the girls drinking juice in the crib — one girl seeming to feel the other gulp — particularly intrigued Feinberg. “ ‘I felt Tatiana drink that,’ ” he said, musing on the idea of it. “Now, how crazy is that? I mean, seriously! This is beyond empathy — it’s like a metasensory experience. It’s like she has one consciousness and can witness another’s.”

As profound as it is to consider that each may witness the other’s consciousness, equally striking is their ability to maintain their individuality. In his book, “Altered Egos: How the Brain Creates the Self,” Feinberg describes patients with various split-brain syndromes, cases in which the corpus callosum, the part of the brain that serves as a bridge connecting one hemisphere to the other, is severed. In one manifestation, a patient might find that one of his hands is at odds, or all-out war, with the other. The unruly hand might throw a spoon or tear up money — actions that do not originate with any desire of which the patient is aware. Yet aside from the alien hand, the patient still feels essentially like himself: such patients “act, feel and experience themselves as intact,” Feinberg writes. Feinberg says the brain labors to create a unity of experience, knitting together our partial selves via numerous cortical mechanisms into a unified whole, into a sense of self, a consistent feeling of individuality and agency.

That the girls each have clear distinction, despite what he considers to be the likely leakage of sensory impressions, was telling to Feinberg. “With the split brain, you essentially cut the brain in half, yet the person feels and acts as a whole,” Feinberg said. “In these girls, they’re linked, yet each acts as a whole. It’s like a force of nature — the brain wants to unify.”

To the family, questions about whether the girls are two or one are so absurd as to be insulting. They are “two normal little girls who happen to go through life sharing a bubble,” Simms said. The family sees their unusual neural connections as something “neat,” as Louise, the grandmother, puts it, providing fascinating moments they notice but hardly lie awake at night contemplating. Of far greater concern to them is the girls’ physical health. “Every day when I wake up and they’re still alive — that’s a good day,” Simms told me.

The trip to Vancouver for medical checkups in January was reassuring in most regards. Their cardiologist was pleased to report that Tatiana’s heart seemed better able to handle her disproportionate burden of blood pumping. Their ophthalmologist was less sanguine. The girls have significant eye problems; to strengthen their vision, they need to wear eye patches and glasses but at the time of the appointment had not been doing so daily. The doctor warned the family with some gravity that the girls each risk becoming legally blind in one eye.

In some ways, the girls have clearly benefited from the family’s relaxed approach to child rearing: no one coddles them, and the girls are happy, affectionate and confident. But the ophthalmologist was concerned that not enough attention was being paid to some details of their care, and the dentist had similar concerns. Tatiana’s teeth are in such bad shape that she is scheduled for surgery this summer.

When the girls were younger, each experienced several seizures, which medication has since controlled. At an appointment with Hukin, their neurologist, she asked if they had any episodes recently (they had not, in more than a year), then performed a few quick tests. She put a red crayon in front of Tatiana, a purple one in front of Krista, then asked them to name the color. “Blue,” Tatiana said. “Red,” Krista said. Did they simply not know their colors? “They’re switching them,” their grandmother said; Hukin agreed it was a possibility. Hukin pulled a stuffed animal out of a bag, a turkey, and handed it to Tatiana on her right side, so that Krista could not see. “Krista, do you know what Tatiana has in her hand?” she asked. Krista paused. “Robin?”

Hukin, at the time, said nothing more than “very good.” But she considered this close-enough answer extraordinary, she later told me, and took it as clinical support for the sensory connection that Cochrane’s EEG tests had revealed.

Over the course of the days I spent with them, I witnessed the girls do seemingly remarkable things: say the precise name of the toy that could only be seen through the eyes of her sister or point precisely, without looking, to the spot on her sister’s body where she was being touched. But other times, the theoretical connection seemed to fail them. The family believes that making the effort to “tune in” sometimes tires them out. It’s possible that they are developing in such a way that their brains are trying hard to filter out input that originates from the other girl’s body.

David Carmel, a cognitive neuroscientist at New York University, suggested that even when the girls deliver right answers, the phenomenon could be explained by something other than a neural bridge. “If they’re really close, through minute movements that one makes — maybe a typical movement her sister cannot see, but can feel — the other sister intuits the association. Maybe she associates her sister’s reaction with a robin they once liked, not a turkey.” The connection then might be scientifically mundane, but a marvel nonetheless to the casual observer.

For the girls, Vancouver represents the outside world: they go to the hospital, they run around a McDonald’s at the mall. They are beloved at the hotel where they normally stay — their “hotel home” they call it — and bring bathing suits so they can float in the pool. On this trip, they ran up and down the hallways of the hotel, their high, sweet voices ringing out, giggling and giddy with liberation. Guests might have looked for a half-second longer than they ordinarily would, but they invariably smiled at the sight of the girls’ evident glee, just as they would at any other two small children.

The second evening they were there, a man in the hotel bar came out to the lobby to talk to them — he was a twin himself, he said, and had to meet them. He and his colleague smiled at the girls, asked them some questions, pronounced them adorable and returned to their waiting drinks inside the bar. But when the girls ran by the bar again an hour later, the same man came out with tears in his eyes. He had obviously been thinking about them and their family and his own. The year before, he said, he had lost his adult son to suicide. “So tell the mother they are blessed,” he said.

The message, relayed to Simms in the hotel restaurant, where the family was dining, did not particularly faze her: people often share their family tragedies with her. Simms understands the impulse, but feels they are trying to empathize with someone whose feelings they do not actually understand. “They feel sorry for us,” Doug McKay, the girls’ step-grandfather, said. “But we feel like we got chosen out of millions of people to be their parents. That’s better than the lottery.”

As I watched the girls negotiate their occasionally conflicting impulses at dinner, I thought of how my friend Peter Freed, a neuroimager and assistant professor of clinical psychiatry at Columbia, explained their possible experience of each other: “It’s as though the secretaries of Goldman Sachs and Lazard Frères have decided, without their bosses’ permission, to share certain visitors and executive memos with each other.” The executives in charge — the parts of the brain more directly involved in decision-making — would inevitably become frustrated. Every time that executive next door makes a decision, the results are “subtly influencing or altering the information the other has to work with,” says Freed, who also writes a blog called Neuroself about the construction of the self in the brain.

The frustration of one executive was on full display as the evening wore on. The girls were tired. It was late for them. Someone ordered them chicken fingers, and Krista took a bite. Suddenly, Tatiana made a face. “It’s too yucky,” she said, starting to cry. The mayhem level went up a notch, and Tatiana crawled under the table, wailing, as Krista was trying to pull her back up by the force of her neck. Krista tried to put the chicken finger directly into Tatiana’s mouth. “Krista likes it!” she said. “It’s yummy!” Tatiana spit the food out, crying: “Let me hide! Let me hide!” She covered her mouth with her hand. “Don’t make her eat it, sweetie,” said their grandmother, as Doug sighed in frustration. “Sissy eat it!” Krista said again, trying to push it in Tatiana’s mouth. Krista started pulling her sister’s hair, and then both girls were crying. Tatiana’s futile declaration rose above the sounds of the restaurant. “I am getting out of here!” Tatiana sobbed. “Let me alone.”

As would be true of any other two sisters, the girls’ relationship to each other and to their unusual connection is unpredictable. Their union could prove, as their grandmother predicts, a model of boundless, blissful empathy. The girls will show the world “true love,” she once said, tearing up. But their lives could also entail a barrage of confused impressions, with each girl having just enough of a sense of self to resent the intrusions of the other’s. Over time, would the girls increasingly tune out each other’s perceptions, with some kind of neural pruning doing the work that surgery could not? Or would some complicated, constant interplay of sensory input and response further fuse their personalities, rendering them ever more like one? Would they have any say in the matter?

Only one set of conjoined twins has ever made the adult choice to be separated, according to “One of Us,” a book by Alice Dreger that traces the history of cultural responses to conjoined twins. Ladan and Laleh Bijani were craniopagus twins who grew up in Iran. When they were 29, they were so desperate to live apart that they decided to take the 50-50 odds that they were given of surviving a separation. In 2003, in the hands of highly regarded surgeons in Singapore, they died after surgery. Despite the countless high-tech brain images they had produced, the surgeons were caught unaware by a major vein the women shared. They thought they had seen inside; but what they learned, tragically, was how little they knew about the union after all.

Tatiana and Krista will start kindergarten in the fall, their first major foray into the outside world. And their lives may soon change even more significantly if Chuck Harris, a talent manager who also manages the Schappells, has his way. Harris has been helping the family pursue a reality television show, not just about the girls (a detail upon which he insists) but also about the range of strong personalities living together in their small home. The decision to expose the girls to the gawkery of the American public is less fraught for the family than you might think — partly for financial reasons, but also because the girls are unlikely to have a normal childhood under any circumstances. The constant exposure, in some ways, would actually normalize them for the public, show them as they are, not as the people who pass them in malls perceive them.

The girls are used to showing off their tricks (so much so that at one point, Krista put her hand on my eyes and asked me to tell her what she was seeing). And they are infinitely proud of the small things they can do that were twice as challenging for them to learn as for someone who moves independently. They like to show how they can jump up and down, which they do like any other children, or climb into their crib, which they do like self-taught gymnasts.

The twins are most moving, however, when they are least aware of how profoundly different they are. One evening, shortly before the girls went to bed, I reached out and touched the tiny birthmark below Krista’s shoulder. “Don’t touch my pen mark,” Krista said. She touched the small dot of red and stroked it with her finger. Her sister, who has no birthmark there, stroked the same spot on her own body, in just the same way, drawing a line downward. She wore the same injured facial expression as her sister.

It seemed to me that at bedtime, the two girls were more like one than when they first arose, as if the labors of the day steadily eroded whatever barriers separated them. Sometimes Krista, the physically stronger of the two, seemed to morph before my eyes, no longer one of two, but instead, a sturdy girl carrying around an elaborate appendage she considered part of herself. Perhaps, in submitting, Tatiana felt a kind of relief, the kind we all feel when we cede control to someone we trust. But I also felt a sense of loss — where was Tatiana in all her totality in those moments?

The night I watched them doze off, both girls faced the bed, and then Tatiana started climbing up its side with her feet, using Krista as a kind of bracing post. From there, Krista jumped up to join her sister the usual way. Once their grandmother quieted the girls down in their oversize crib, they finally lay down on their backs. Each girl put an inner hand in her mouth, with four bent fingers, then let it fall back to her side. Each held a doll in her outer hand, threw it over her face and then pulled it away. They sighed simultaneously. Soon Krista was asleep; an instant later Tatiana was as well. They had both flung their inside arms up and over their own eyes, so that they were mirror images of each other at rest. Then Tatiana alone moved her arm away, and the girls drifted off for the night, to dream, together or apart, their secret dreams.

Wednesday, February 10, 2010