A Poor Sense of Smell May Point to Brain Trouble

New research ties dementia predictions to olfactory results



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If you can smell the difference between pineapple and paint-thinner, that’s a good sign: You may be more likely to keep your marbles well into the future. So says a new study on the predictive power of our sense of smell.

In a paper published in the journal Neurology in December, neurologist Kristine Yaffe and her team discovered that older adults with a keen sense of smell are less likely than their peers to develop dementia as they age. In contrast, a blunted sense of smell, much like an altered sense of humor or sense of direction, may presage more pervasive cognitive losses in the years ahead.

Previous research had led Dr. Yaffe, who is a professor of psychiatry and neurology at the University of California, San Francisco, to suspect that people with a diminished ability to identify odors might be at increased risk of dementia. Olfactory nerve fibers project into the brain’s centers for memory and emotional processing, which suggests a connection between those cells and smell-related ones.

Dr. Yaffe’s research team followed 2,428 healthy adults in their 70s, all participants in a national, ongoing study of aging. Previous studies on the topic were often confined to white populations. This time the research team created a group that was half black, half white as well as half male, half female.

Three years into the study, the researchers assessed the participants’ sense of smell using a standardized test of 12 common scents. The test required the subjects to inhale a series of airborne chemical compounds present in foods like onion, lemon and chocolate, as well as in environmental odors, such as smoke and gasoline. After each whiff, the subjects had to identify what they had just smelled, which resulted in their “odor identification score.”

The researchers then monitored the participants’ psychological and medical status for the next nine years, using a memory test and their medication and hospitalization records. The team controlled for other factors that could increase the risk of memory loss, such as a prior smoking habit, a history of head trauma, depression or a genetic predisposition for Alzheimer’s disease. With those factors statistically stripped away, the experimenters found that on tests for sense of smell, men trailed women slightly and blacks lagged a bit behind whites.

What mattered most, though, were comparisons within the racial and gender groups. People of either race or sex who had more trouble identifying smells were indeed more likely to develop dementia—despite having no signs of cognitive decline when they signed up for the study, nor during its first three years.

Among whites, the weakest smellers (the lowest third of the group) had three times the dementia risk as the highest third. Among black participants, the weakest group had two times the risk. Subtypes of dementia may explain the difference. Smell is a better early predictor of Alzheimer’s. Blacks, Dr. Yaffe said, have a greater risk of developing vascular dementia, which causes diffuse neural deficits, than Alzheimer’s, which leaves more tangles and plaques near the olfactory nerve.

“What’s happening,” she added, “is that abnormal proteins are building up over decades, and some of the early changes start in the olfactory bulb, the brain structure that receives neural information about odors. “When you think about how our brains evolved, it’s not a shocker that olfaction, considered an older part of the brain, would reflect degenerative processes first.”

In all, 491 of the participants developed dementia at the end of 12 years.

That a compromised sense of smell may be a biomarker for dementia is both good news and bad news. An early warning signal has limited use, since no drug yet exists to head off Alzheimer’s (though several medications are being developed that target its symptoms). Still, those who can’t smell shouldn’t panic. Researchers emphasize that a mildly dialed down sense of smell and taste—much like mild hearing loss—is just a feature of aging.


Watching Terror and Other Traumas Can Deeply Hurt Teenagers

The focus: web exposure to the Boston Marathon bombing



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Several weeks into the Gulf War in 1990, when I was working as a clinical psychologist in Montreal, pediatricians started referring children with mysterious behavior problems. A few 8- to 10-year-olds had started to wet their beds for the first time since they were toddlers. Others were refusing to go to school. Their first interviews revealed a common thread: Though strangers to each other, the children and their families were all visitors or immigrants from Israel, and they had been watching Scud missile attacks against Israel on the news every day.

These children were living more than 5,000 miles from the bombing, but observing the devastation from afar—and their parents’ reactions to it—had elicited an emotional response that skewed their habits. New research is now helping us to understand how second-hand exposure to disasters can change our brains and behavior, and who is most at risk.

“We used to think of it as a bull’s-eye. The closer you were to the trauma, the more likely you were to show symptoms,” said Jonathan Comer, a professor of psychology at Florida International University who investigates the impact of terrorist attacks on children and families. “But a summary of post-9/11 reactions really challenged that idea.” Those closest to the event didn’t necessarily show the most trauma, said Prof. Comer.

Prof. Comer’s own research upends our assumptions about who is most prone to feel psychological fallout after a terrorist attack. In a 2016 study of the Boston Marathon bombing published last summer in Evidence-Based Practice in Child and Adolescent Mental Health, the research team surveyed nearly 500 parents of 4-to-19-year-olds about their children’s internet exposure during the bombing and the manhunt that followed. The surveyed families all lived within 25 miles of either the bombing site itself or Watertown, Mass., where the police had ordered the local population to shelter in place during a search for suspects.

The findings? As one would expect, exposure to graphic online content rose with age. Over 23% of children saw internet images of the bombing, and 68% viewed footage of police with military-grade weapons searching their neighborhoods. The average was two to three hours of daily online activity per child. While those under age 8 were less exposed, three-quarters of children over 12 spent up to 6 hours daily viewing online news and social media coverage of the crisis.

Teenagers were the most prone of all age groups to experience psychological trauma after the bombing. The researchers found that the more internet news and social media contact they had about the bombing and manhunt, the more severe were their PTSD symptoms, which ranged from intrusive flashbacks to emotional numbing. What’s more, even if 87% of parents believed that online exposure to the crisis could be damaging, very few restricted their children’s access to it. And what parents thought was private—their own fear—turned out to be contagious, too, as shown in a 2014 study of parents’ reactions to the marathon bombing by Prof. Comer’s team.

To understand how observational distress works, a team led by Alexei Morozov at Virginia Tech Carilion Research Institute looked at what happens when mice watch a sibling experience fear. He first learned that vicarious fear leaves a neural trace that predisposes animals to experience trauma later on. A Morozov-team study published last month in Neuropsychopharmacology found that vicarious trauma changes the connections between the amygdala (roughly, our emotion and survival center) and the prefrontal cortex (the planning and decision-making area). “After the animal has the experience of the other’s pain, it allows excitation to be more robust…it reduces the ability of the prefrontal cortex to act rationally,” he told me.

That’s one reason why “watching around-the-clock breaking news is not in our best interest—either for adults or children,” said Jonathan Comer. Because it’s not how much danger we’re in that matters. It’s how much threat we perceive in others.

What You Just Forgot May Be ‘Sleeping’

Can’t remember what you were just thinking about? A new study amends our understanding of how memory works



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If you’ve ever forgotten why you just entered a room, you know how fickle memory can be. One moment it’s obvious why you walked down the hall, and the next moment you’re standing there befuddled.

Here today, gone in a millisecond. At least that’s how we used to think about short-term, or working, memory. But a study just published in the journal Science tells a different story. A recent idea or word that you’re trying to recall has not, in fact, gone AWOL, as we previously thought. According to new brain-decoding techniques, it’s just sleeping.

“Earlier experiments show that a neural representation of a word disappeared,” said the study’s lead author, Brad Postle, a professor of psychology and psychiatry at the University of Wisconsin-Madison. But by using a trio of cutting-edge techniques, Dr. Postle and his team have revealed just where the neural trace of that word is held until it can be cued up again.

Their study amends the long-standing view of how memory works. Until now, psychologists thought that short-term memory evaporates when you stop thinking about something, while long-term memory permanently rewires neural connections. The new research reveals a neural signature for a third type of memory: behind-the-scenes thoughts that are warehoused in the brain.

In the study’s four experiments, a total of 65 students viewed a pair of images—some combination of a word, a face or a cloud of moving dots—on a screen. During a 10-second period, the students were prompted to think about one of the two images they had seen. After a brief delay, they had to confirm whether a picture they saw matched one of the first two images.

Throughout the experiment, the Postle team monitored the students’ pattern of neural activity. When they prompted the students to remember a particular image, a unique 3-D display of neural activity corresponding to that idea popped up. What really interested the experimenters, though, was what the brain was doing with the image it had effectively set aside. Where did that memory go while it was waiting in the wings?

To find out, the team used a new technique to see what happened when the participants were warned that they would be tested on the set-aside image. This novel approach created a dynamic 3-D display of electroencephalogram (brain wave) and brain-imaging data that let the researchers see beyond what part of the brain “lights up” and zoom in on the pattern of activity within a region. That’s how the team learned that the students’ brain activity had indeed shifted to the “on hold” image’s distinctive pattern—which until then had been invisible.

To confirm that the memory still existed even while a person was not thinking about it, the scientists used another recent technique, transcranial magnetic stimulation, or TMS. They positioned a wand over a participant’s scalp and delivered a harmless magnetic pulse to the brain areas that held the images. The pulse made the distinctive neural signature of those fleeting memories visible to the scientists and triggered their recall in the students.

Dr. Postle compared working memory to paper inscribed with invisible ink. Words written in lemon juice are initially imperceptible, but by passing a hot cup of coffee over the paper, “you can see the part of the message that was heated up…. Our TMS is like the coffee cup.” In this way the team activated a memory that was not only temporary but below the student’s level of consciousness.

Using Dr. Postle’s new trifecta of brain-imaging and brain-stimulation techniques to reactivate forgotten memories has enticing—though still remote—therapeutic possibilities. It is neuroscience’s most faithful reading yet of the real-time content of our thoughts—about as close as we have ever come to mind-reading.

“Our study suggests that there’s information in the penumbra of our awareness. We are not aware that it’s there, but it’s potentially accessible,” said Dr. Postle.

Why Lessons From Chimp Mothers Last a Lifetime

A grooming study suggests the powerful influence of moms (human ones, too)



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My mother taught me how to cook, learn my times tables and read with a critical eye—and, in the social realm, how to mind my manners and reach out to others.

But maternal mentors are hardly exclusive to humans. Vervet-monkey moms show their infants their own way to clean off fruit, while chimpanzee mothers teach their toddlers just which stick is best for termite-fishing and how to use rocks to crack nuts. Some bottlenose-dolphin mothers show their young how to find sponges to protect their sensitive snouts while scouring the sea floor for treats—a safety measure that resonated with the mother in me.

New evidence shows that some mammal mothers—specifically, chimps—also transmit to offspring their unique style of socializing. (In contrast, nonhuman primate fathers rarely get involved in teaching children.) The new research focuses on grooming, a primary feature of an ape’s social life.

Chimp grooming does double duty: Picking through another animal’s fur controls parasites and also establishes a trusting social bond. Grooming can be a relaxing pastime, a come-on or a way to forge alliances. As with human social behavior, chimps do it in different ways.

In what primatologists call “high-arm grooming,” two chimps groom each other face-to-face, each with one arm raised in the air. Using their opposite hands to comb through each other’s fur, the pair might be clasping their raised hands aloft or leaning their forearms together overhead. Either way, chimps of both sexes practice this unique grooming style well into adulthood.

While male chimps stay where they are born all their lives, most females migrate to new groups at adolescence. Wherever they end up, the ones from the high-arm, hand-holding community then teach this endearing posture to their own progeny. “It’s a social custom inherited from mother to offspring and not known in any primate before,” said Richard Wrangham, a professor of biological anthropology at Harvard. He and his team observed this unusual behavior among wild chimps living in the Kanyawara community of Uganda’s Kibale National Park.

As described last month in the journal Current Biology, the researchers analyzed 932 photos of high-arm grooming among 36 wild chimps, half of them female. The team had expected that when the adolescent female chimps immigrated to a new community, they would conform to its customs. Teenagers like to fit in, after all.

But a close look at which chimps held hands showed that what mattered is how mom did it. “We’ve got individuals up to 40 years old who are following the maternal pattern,” Dr. Wrangham told me, adding that even after the mother dies, her offspring keep doing things her way.

Intriguingly, hanging out with other family members or peers made no difference in grooming style—regardless how close the relationship or how much time the animals spent together. That makes sense, given that primate mothers are crucial to the education and survival of their offspring. In a 2006 study of wild chimps in Tanzania’s Gombe National Park, the amount of time spent watching mom fish for termites correlated with how skilled 6-year-old chimps became at that task. Female children copied their mothers more faithfully and so became more efficient learners.

Human mothers also have a uniquely powerful effect on their children’s behavior. As mammals and primates, they take time to coach their young ones, who then copy what they do. I’m not discounting the importance of fathers, but it looks like we belong to a large evolutionary family that learns enduring lessons at our mothers’ feet.

Empathy by the Book: How Fiction Affects Behavior

Not all genres have the same effect, research shows



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When I want to escape I pick up a good novel. But does this habit provide more than a quick getaway?

We’ve long known about the collateral benefits of habitual reading—a richer vocabulary, for example. But that’s only part of the picture. Mounting evidence over the past decade suggests that the mental calisthenics required to live inside a fictional character’s skin foster empathy for the people you meet day-to-day.

In 2006, a study led by University of Toronto psychologists Keith Oatley and Raymond Mar connected fiction-reading with increased sensitivity to others. To measure how much text the readers had seen in their lifetimes, they took an author-recognition test—a typical measure for this type of study. “The more fiction people read, the better they empathized,” was how Dr. Oatley summarized the findings. The effect didn’t hold for nonfiction.

Still, no one knew whether reading fiction fostered empathy or empathy fostered an interest in fiction. Other factors could have been at play too, like personality.

So, in 2009, part of the Oatley-Mar team involved in the 2006 study reproduced it with a sample of 252 adults—this time controlling for age, gender, IQ, English fluency, stress, loneliness and personality type. The researchers also assessed participants’ “tendency to be transported by a narrative”—the sense that you’re experiencing a story from within, not watching it as an outsider.

Finally, participants took an objective test of empathy, called the Reading the Mind in the Eyes Test. The aim of all of this was to see how long-term exposure to fiction influenced their ability to intuit the emotions and intentions of people in the real world.

The results? Once competing variables were statistically stripped away, fiction reading predicted higher levels of empathy. Such readers also lived large in the flesh-and-blood social sphere, with richer networks of people to provide entertainment and support than people who read less fiction. This finding put to rest the stereotype of bookworms as social misfits who use fictional characters as avatars for real friends and romantic partners.

Later studies confirmed that reading fiction does cause a spike in the ability to detect and understand other people’s emotions—at least in the short term. In a series of experiments published in 2013 in Science, social psychologist Emanuele Castano and David Comer Kidd of the New School for Social Research tried to figure out whether the type of fiction mattered.

The researchers handed subjects—in groups ranging in size from 69 to 356—different types of genre fiction, literary fiction or nonfiction, or nothing to read at all. They then assessed participants on several measures of empathy. Nonfiction—along with horror, sci-fi or romance novels—had little effect on the capacity to detect others’ feelings and thoughts. Only literary fiction, which requires readers to work at guessing characters’ motivations from subtle cues, fostered empathy.

In these studies, the reading of nonfiction not only failed to spur empathy but also predicted loneliness and social isolation, specially among men. Of course, nonfiction reading has its virtues. Other research suggests that various kinds of nonfiction can prompt empathetic feelings—as long as the narrative is moving and transformative.

In recent studies, neuroscientist Paul Zak at Claremont Graduate University and colleagues showed participants heartfelt stories, such as a video narrated by a father of a toddler with brain cancer. The video induced a spike in observers’ levels of oxytocin—a hormone that promotes trust, nurturing and empathy—and larger donations to charity. Watching a straightforward travelogue-type video of the same father and son visiting the zoo didn’t have that effect.

Apparently, what matters is not whether a story is true. Instead, as Dr. Oatley says, “If you’re enclosed in the bubble of your own life, can you imagine the lives of others?”



When We Display Our Piety, Our Social Stock Rises

People perceive signs of religious observance in others as a measure of dependability, new research shows



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One of the many unusual aspects of this presidential campaign has been how little the candidates have discussed religion. Compare this with two previous presidential contenders, among many others who publicly affirmed their faith. When asked in 2000 to name his favorite political thinker, George W. Bush replied, “Christ, because He changed my heart,” while a 1980 ad for Jimmy Carter’s unsuccessful re-election campaign intoned, “He takes the time to pray privately and with Rosalynn each day.”

Perhaps one reason for the change is that “none” is the fastest-growing major religious affiliation in America, as a Pew Research Center survey showed last year. Given this shifting terrain, does being visibly devout still signal that you can be trusted?

Surprisingly, the answer is yes. People perceive signs of religious observance in others as a measure of dependability, new research shows. Whether one fasts on Yom Kippur, wears a cross of ash for Lent or places a red dot in the middle of one’s forehead, such religious “badges” do more than just signal that you belong to a particular group. Other people see these displays as a shorthand for reliability.

In four experiments published last year in the journal Psychology of Religion and Spirituality, the anthropologist Richard Sosis of the University of Connecticut and his colleagues altered one fifth of the images so that people appeared to be wearing a cross around their necks or a cross of ash on their foreheads. The experiments were conducted between Ash Wednesday and Easter. The researchers interspersed these images with those of people without any religious adornments.

Several hundred university students of varying backgrounds then examined the stack of photos, rating each of the faces for trustworthiness. The students also played an economic game during which they entrusted money to players whom they deemed honorable.

The researchers were surprised to discover that a person wearing Christian religious symbols prompted powerful feelings of trust, not only among fellow Christians but also among secular students and members of other religions. The presence of a cross doubled the money that non-Christians were willing to offer someone in the trust game, while the Ash Wednesday cross increased their investment by 38.5%.

Other recent studies show that the effect is the same for any religious practice that imposes a cost on the appearance, comfort or finances of believers, or that restricts their diet or sexual behavior. Whether they are MuslimsJews or Hindus, such displays of devotion burnish the reputations of the observant.

In a fascinating study of Hindu and Christian villagers in South India, published this year in the journal Evolution and Human Behavior, the anthropologist Eleanor Power found that local religious rituals greatly enhanced a participant’s standing in the community. For both Catholics and Hindus, these included onerous pilgrimages; Hindu rituals included walking across burning coals and being suspended by hooks in one’s skin. Participation in these widely accepted demonstrations of devotion also predicted which individuals had pivotal roles in local social networks.

“People are more likely to go to you for support if you undertake such religious acts,” said Dr. Power of the nonprofit Santa Fe Institute. She had access to temple records showing who paid religious fees and joined pilgrimages and processions, along with villagers’ evaluations of their peers and their status in the community. “People will rate you as having a good work ethic, giving good advice and being more generous if you worship regularly and do firewalking or other costly acts,” Dr. Power told me.

Such religious displays make us more likely to turn to these people for leadership. Today’s presidential contenders would perhaps benefit from a greater show of reverence. The harder they work to convey that they believe in something greater than themselves, the more credible they will be to voters.



Marijuana Makes for Slackers? Now There’s Evidence



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In cities like Seattle and Vancouver, the marijuana icon has become almost as common on storefronts as the Starbucks mermaid. But there’s one big difference between the products on offer: A venti latte tastes the same everywhere and provides an identical caffeine rush, while marijuana stores offer the drug’s active ingredients in varying combinations, potencies and formats. There is no consistency in testing, standards or labeling.

This matters because marijuana’s two psychoactive ingredients, tetrohydrocannabinol (THC) and cannabidiol (CBD), have contrasting effects on the brain. “THC makes you feel high,” said Catharine Winstanley, a psychology professor at the University of British Columbia who does research on marijuana, while CBD “is responsible for its analgesic, antiseizure and purported anticancer effects.”

In street marijuana, the THC-to-CBD ratio now tends to be 10 to 1, and it is increasing, a trend occurring even at some marijuana clinics, Dr. Winstanley said. And few people know what effect that has on their brains. A new study by Dr. Winstanley’s group in the Journal of Psychiatry and Neuroscience examines how these two chemicals shape our willingness to face a challenge. Does marijuana make us lazy?

To answer this question, the Winstanley team first tested rats to determine which were hard workers and which were slackers. After being injected with THC, CBD or both, the rats had to choose between a simple task with a measly reward or a demanding one that reaped a bigger payoff.

In the easy version, the animals had a minute—an eternity for a rat—to see that a light was on in a chamber and poke their noses inside. They got a single sugar pellet. In the hard version they only had a fifth of a second to notice the light—something a rat, even a stoned one, should have no problem perceiving—and respond. Their vigilance in the hard choice would earn them two lumps instead of one. Under normal circumstances, the vast majority of rats prefer to work harder for a bigger payoff.

The results? “Whether they were workers or slackers to begin with,” Dr. Winstanley reported, “even small amounts of THC made them all slackers.”

THC didn’t impair the rats’ ability to perform, only their willingness to try. That downshift in motivation didn’t happen in rats injected with CBD only.

Later analysis of the rats’ brains showed that those with the greatest reaction to THC also had a greater density of a particular receptor in their anterior cingulate cortex, or ACC. “That area of the brain is very important for people to gear up to face a challenge and stay the course,” Dr. Winstanley said.

A small study shows something similar in humans. Published this month in the journal Psychopharmacology by a University College London team, the study of 17 adults showed that inhaling cannabis with THC alone (versus pot with CBD plus THC, or a placebo), induces people to choose an easy task more often, eschewing the harder one that offered four times the payoff. Neither the researchers nor the subjects knew who had gotten the drug, who the placebo. The effects were short term, meaning that the subjects’ apathy didn’t persist after the high wore off.

The need for policy-makers to deal with the results of tests like these is complicated by the lack of regulatory consistency. That’s because the U.S. Drug Enforcement Administration considers marijuana as illegal as heroin, while 25 states and the District of Columbia have legalized pot for various purposes. So no national standards exist.

“Thinking that it’s harmless, that you can smoke cannabis and you’ll be fine, is a false assumption,” said Michael Bloomfield, a University College London professor in psychiatry and one of the UCL study’s authors. “THC alters how willing you are to try things that are more difficult.” So next time you go to a clinic—or dealer—you might want to ask about the product’s chemical breakdown.

Medicating Children With ADHD Keeps Them Safer

New research suggests that medication can reduce risky behavior in teenagers with attention deficit hyperactivity disorder, or ADHD




Updated Aug. 17, 2016 10:23 a.m. ET

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If a pill could prevent teenagers from taking dangerous risks, would you consider it for your children?

I’d be tempted. My skateboard- and bicycle-riding son was hit by a car—twice—when he was a teenager. I would have welcomed anything that could have averted those dreadful phone calls from the emergency room.

While some bumps and scares are inevitable for active guys like him, serious misadventures with long-lasting repercussions are often par for the course for a subset of them—those with attention deficit hyperactivity disorder, or ADHD. But a new article suggests that early medication can significantly cut the odds of bad things happening later.

Affecting nearly 9% of all Americans between 4 and 18 years of age, ADHD is one of the most common childhood disorders and also one of the most misunderstood. Its symptoms color almost every aspect of a child’s life—from being able to focus in school to making and keeping friends, reining in fleeting impulses and assessing risk and danger.

Indeed, accidents are the most common cause of death in individuals with ADHD, withone 2015 study of over 710,000 Danish children finding that 10- to 12-year-olds with ADHD were far more likely to be injured than other children their age. Drug treatment made a big difference, however, nearly halving the number of emergency room visits by children with ADHD.

Medicating children to address problems with attention and self-control remains controversial. ADHD isn’t visible, like chickenpox, nor immediately life-threatening, like asthma. Its distortion of a child’s ability to meet adults’ expectations creates an atmosphere of frustration and blame. So it’s not often taken for what it really is: a neurodevelopmental disorder with genetic roots.

An enduring myth about ADHD is that children grow out of it in adolescence. We now know that a 5-year-old with a bona fide attentional disorder may well become a dreamy, restless and impulsive teenager and adult. Adolescents with ADHD think even less about consequences than the average teenager and are especially thrilled by novelty. They’re more likely than their friends to drink too much, drive like maniacs, abuse drugs and have unprotected sex.

It’s a sobering list. But an article published last month by Princeton researchers Anna Chorniyand Leah Kitashima in the journal Labour Economics shows that treating ADHD with medication during childhood can head off later problems. “We have 11 years of data for every child enrolled in South Carolina Medicaid who was diagnosed with ADHD,” Dr. Chorniy told me. The researchers tracked each doctor visit and every prescription, with a sample of over 58,000 children whose health progress they tracked into adulthood.

This long view let the economists compare the behaviors of teens treated with the most common ADHD medications, such as Ritalin, Concerta and Adderall, to the types of risks taken by other children with ADHD who were not treated. The researchers found fewer and less severe injuries and health problems among the treated children: a 3.6% reduction in sexually transmitted infections; 5.8% fewer children who sought screening for sexually transmitted infections (suggesting they had had an unprotected sexual tryst); and 2% fewer teen pregnancies.

That adds up to a lot fewer teenagers in trouble.

The economists did their study based on existing data, but randomized, controlled studies—experiments carefully designed to establish cause-and-effect relationships—have reached the same conclusion: that medication to control ADHD can reduce the high price in psychic pain, loss of educational opportunity and riven relationships. A child whose disorder is diagnosed and treated early by a trained clinician stands a better chance of growing into a healthy and thoughtful adult.


For Better Performance, Give Yourself a Pep Talk

‘Self-talk,’ stories we tell ourselves to change unwanted thoughts, can help us manage our feelings as well as boost our performance—even beyond sports

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Most of us yearn to bump up our game. Indeed, telling ourselves we’re better than the competition is so central to the American psyche that self-doubt can seem almost unpatriotic. But does egging ourselves on really help us to get better at anything?

Psychologists have long known that “self-talk” or “self-instruction”—that is, the stories we tell ourselves to change unwanted thoughts and behaviors—can also transform moods. As one feature of cognitive-behavioral therapy, self-talk—such as saying, “I am an interesting person who can make new friends” or “I can focus on one task at a time”—helps depressed people to revamp their way of thinking and thus their ability to cope.

Now a massive online study suggests that such talk can help us not only to manage our feelings but also to boost our performance—and relatively quickly, too.

The recent study takes its cue from sports psychology, which shows that self-instruction can push athletes to persist on quick tests of endurance or on highly technical bursts of effort, such as volleyball serves.

British sports psychologist Andy Lane at the University of Wolverhampton led the experiment in conjunction with the BBC Lab, a (now closed) arm of the broadcasting service, which invited volunteers to be citizen scientists. In an interesting twist on attracting research subjects, actor Ricky Gervais and Olympic sprinter Michael Johnson promoted the study on BBC TV before the 2012 London summer Olympics. Nearly 45,000 people participated, an enormous sample for a study in psychology.

The volunteers filled out questionnaires on home computers about their emotions and played a series of online number-finding games, with instructions and feedback narrated by Mr. Johnson. The yearlong study came out in March in the journal Frontiers in Psychology.

After completing practice and baseline tests, participants were randomly assigned to one of four groups: self-talk, imagery (e.g., imagining oneself reacting more quickly), “if-then planning” (e.g., planning a reaction to what might happen while competing) and a control group, which encouraged reflection on performance but didn’t give any instructions or motivational hints. The subjects had to beat their previous performance as well as an “opponent”—actually a computer algorithm matched to their skill level. The scientists wanted to know which of the interventions would help people to manage their emotions when under pressure.

The results showed that simple self-talk—like saying “I want to be the best” or “I’m going to try as hard as possible”—was the most effective technique, especially if the script was about increasing motivation. Self-talk focused on specific goals, such as “I’m going to get a score of 90,” didn’t work as well.

One caveat: There’s a world of difference between effort and skill—as anyone who has ever tried to swim faster or master the violin knows well. Roy Baumeister, a psychology professor at Florida State University, said that a number-finding challenge (like that in Dr. Lane’s study) “is based on effort; there’s not much skill involved. In that context, self-talk can help with effort. I’m not so sure about skill.”

Dr. Baumeister, who has researched how emotion shapes behavior, added that when it comes to skill and effort, “what works with one will not work with the other.” Choking under pressure decreases our ability to show what we can do—it inhibits our skills—whereas pressure usually increases effort, he explained.

Dr. Lane agrees that generalizing his results should be limited to brief tasks that require tremendous exertion—say, weight training or sprinting. “The language you tell yourself in these situations is usually negative, and you get some unpleasant emotions. But you can train your emotions to say, ‘You can endure another five or 10 seconds.’ So instead of being demoralized, you teach yourself to push just a little bit harder and a little bit longer.”

A Pair of Witnesses Can Be Better Than One

New research questions the assumption that police should interview witnesses to a crime separately

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If you witness a crime, what’s the best way to recall what happened? Minutes to months later, police might ask you the color of the perp’s eyes, the design of his tattoo or how long it took him to pull out a gun after he entered the room. Would it be better to recount your story on your own or alongside the person you were with at the time?

Anyone who has ever watched a police procedural can answer that question. Witnesses are always interviewed alone, in a dismal, windowless holding cell—that is, if the interview takes place in Hollywood.

But the isolation of witnesses is not just for dramatic effect. Psychologists have long warned police that one witness can contaminate another’s testimony. Social pressures can make someone change his tune, or errors might be introduced into the testimony.

Contagion and the power of suggestion might also create the feeling that events that never even happened actually occurred. That was the case during the 1980s epidemic of “repressed” memory syndrome, which focused on false claims of childhood sexual abuse. In 2013, researchers at the Massachusetts Institute of Technology were even able to plant false memories in lab mice, leaving neurochemical traces indistinguishable from the neural footprints left by real experiences.

Still, even if memory is highly malleable, two new studies show that there are big benefits in bringing witnesses together to collaborate on testimony. The findings could shake up decades of practice in legal circles.

One study, published in the journal Memory this past May, shows that witnesses who are interviewed together do, in fact, influence each other. But they also correct and amplify each other’s accounts of the same event, increasing accuracy in the process. The opportunity to edit each other’s memories allows pairs of witnesses to make fewer errors than witnesses who are questioned on their own.

Led by the Dutch legal psychology professors Annelies Vredeveldt and Peter van Koppen and colleagues at VU University Amsterdam, the researchers asked people who had recently seen a play to describe a violent, emotional scene. Of 53 adults who saw the same play on three separate nights, 36 came to the theater as couples and were interviewed together afterward. They ranged from spouses to one pair that had just met for the first time. The 17 others were interviewed as individuals. The researchers then compared the two groups. Who would produce a more accurate chronicle of a rape-and-murder scene acted onstage the week before?

The people who came together corrected each other’s errors, as we know. But a second, more intriguing finding surfaced, too: The nature of a couple’s communication skills influenced how much detail they remembered. “People who repeated, rephrased or elaborated on what their partner just said remembered more,” Prof. Vredeveldt told me.

It wasn’t how long they had been married or how well the couple knew each other that mattered. It was their skill in creating a joint narrative. If the husband described the crime victim as wearing “some type of dress,” the wife might add “one that opens at the front.” When the man agreed and added that the dress was white, the wife concurred, then specified that it was “a dirty white.” Because the researchers didn’t examine the features of a pair’s relationship, they plan to find out what happens if the couples are strangers or are asked to remember an event in groups.

A second study, published in Legal and Criminological Psychology in June with some of the same authors, used a larger sample and more controlled conditions—and had the same findings: People interviewed together made fewer errors.

Prof. Vredeveldt still believes that people should be interviewed individually. “But instead of sending them home after that, you might generate more leads and fewer errors if you put witnesses together.” Because when couples are bouncing ideas off each other, “the whole is greater than the sum of its parts.”