Originally posted on April 21, 2014. Aggressive urges crop up, even for the most saintly people. What helps keep our aggressive urges at bay? Self-control. We can override our aggressive urges and do something more constructive. But what makes self-control possible? Most of us struggle with self-control failure when we’re hungry. We might get angrier than usual, a term called ‘hangry.’ In a recent study published in the Proceedings of the National Academy of Sciences, my colleagues and I argue that glucose helps people control their aggressive urges. Glucose fuels the brain, and it takes brainpower to quiet our anger. If people have less brain fuel, they should behave more aggressively. To test the idea, we recruited married couples, asked them to prick their fingers every day to measure their blood sugar levels, and then gave them a chance to express their aggression. Each day, people could stab a voodoo doll that represented their spouse with between 0 and 51 pins. On the last day of the study, people also completed a competitive reaction-time game against their partner, in which they could blast their partner with intense and prolonged noise. (Don’t worry, the game was rigged so that people never actually blasted their spouses.) Low blood glucose related to greater aggression. The lower amount of sugar floated in people’s blood, the more pins they stuck into the voodoo doll and the more their blasted their spouse. To avoid what Popular Science Cartoonist Maki Naro now calls the Hanger Games (click for a sweet cartoon summarizing this research), I have one suggestion: Don’t argue on an empty stomach. ... View more

Originally posted on April 23, 2014. When we select a romantic partner, we want to know the good and the bad. Is he nice? Will she make me laugh? Getting to know the good isn’t too difficult. A first date is when the good is on full display. People primp, prepare questions in advance, and pay more than they otherwise for dinner. But how can you know whether the person who’s getting ready to sweep you off of your feet might later break your heart? Conflict is a part of all relationships. We squabble, argue, and may even insult our loved ones. You have to do more than that to break someone’s heart. To accomplish that feat, something often happens that causes you to question treasured parts of your relationship. This brings us to a common cause of broken hearts worldwide: Infidelity. What might boost the likelihood of infidelity? Gender is a key factor. Men, compared to women, are between two and four times more likely to report engaging in infidelity. Here are two things you probably didn’t know: 1.     Avoidant people—those who keep others at arm’s length, prefer to depend on themselves instead of others, and feel uncomfortable getting emotionally close to their partners—are more likely to engage infidelity. In one set of studies, my colleagues and I recruited people in relationships, measured their level of avoidance, and showed: Their eyes gravitate toward attractive alternatives to their romantic partner. They report more positive attitudes toward infidelity They report more intentions to engage infidelity They report engaging in infidelity more often than others This effect is true for both men and women. 2.     A lack of commitment explains why avoidant people engage in more infidelity. Avoidant people dislike getting close to others. Hence, they have a tough time feeling strong relationship commitment. Their lack of commitment might make avoidant people feel safe and secure. But it also weakens the commitment that often keeps urges to engage in infidelity at bay. The irony is that avoidant people keep others at a distance to prevent social rejection. By having lower relationship commitment, they’re more likely to engage in infidelity—and cause their greatest fear of rejection to come true. ... View more

Originally posted on April 25, 2014. We’ve all experienced it. You’re some place where screaming isn’t tolerated, some kids starts wailing, and the parents rush to quiet them down. What happens next is the twist: “They’re the best behaved kids we know,” the parents say, as their child continues to bellow. We nod our heads, feign a smile, and go back to what we’re doing. Before you pounce on me for being impatient and inexperienced, I’m here to share some good news. The more positively we view our close relationship partners, the stronger relationship we have. The best part is that the positivity doesn’t have to exist. If you ask many people, they’ll tell you their close friends are above average on nearly every positive trait. They’re funnier, smarter, and kinder than their peers. We might have positive illusions, but that doesn’t hurt anything. Or does it? Let’s return to how we see our kids. Seeing them as above average might have certain benefits. It might boost your parenting commitment and satisfaction. Who wants to devote the time and energy it takes to parent if you see your kid as a dud? A recent study suggests a potential drawback: many parents perceive their children as healthier than they actually are. The study, which drew on several investigations involving over 15,000 children, found that half of parents who have overweight or obese children rate their child as slimmer than their weight suggests. Just as people villainize parents of screaming children, it’s easy to attack parents who don’t know their children are overweight or obese. But let’s show parents some empathy. Parenting is hard. I don’t have kids, but I can’t tell you how much respect I have for people who do. Parents might not want to hurt their children’s feelings by calling them overweight or obese. They also might not know what it means to be overweight or obese. Is it simply if your son fits into his clothes? If your daughter comes home crying because a school bully called her fat? But there’s a third possibility: when we love someone, we see them in the best possible light. Instead of seeing an obese child, we see our daughter who jumps down the stairs to welcome us home from work. We see our son who loves to get dirty in the mud. When I read about the study, I tucked it away in my files. The next morning my wife and I took our two golden retrievers, Finnegan and Atticus, to the veterinarian. They’re both of our dogs, but Finnegan is mine and Atticus is my wife’s. They weighed Finnegan, who came in at a beefy 85 pounds. Then it was Atticus’s turn. “He’s much skinnier than Finnegan,” my wife, Alice, said. “Just look at him.” I looked and realized we weren’t seeing the same dog. “He looks the same to me. We feed him the same amount and give him the same amount of exercise.” “Nah, I bet he’s 70 pounds,” she said. They took Atticus away, weighed him, and returned with the results. He was exactly the same as Finnegan: 85 pounds. So, this finding might apply to dog owners, too. ... View more

Originally posted on April 29, 2014. Becoming a psychologist makes it hard to name drop. We rarely know celebrities. We read more than we schmooze. We seldom inform national or international politics. But we do drop the names of famous psychological studies. Few studies get more name dropping than Walter Mischel’s delay of gratification studies, the so-called marshmallow studies.   Some think the marshmallow study recently took a slight beating. Much of the criticism has radiated from the findings of a cool new study. In the study, some children learned not to trust an adult experimenter, whereas others learned to trust the same adult experimenter. Next, they were brought through the classic delay of gratification study procedure. Kids were left alone in a room to stare at a treat with the promise of a larger reward if they resisted eating that treat. The result: Compared to those exposed to a non-trustworthy experimenter, children exposed to a trustworthy experimenter waited longer in order to receive a larger reward. In a recent New York Times Op-Ed, Michael Bourne argues that these results question the depth of Mischel’s classic delay of gratification findings. Yes, the new findings identify a crucial factor – whether or not you can trust an adult experimenter – that can change a child’s delay of gratification. But these findings do little to negate the meaning of the original findings. If anything, they strengthen them. Let’s start by focusing on the kids who learned to trust the adult experimenter. About 64 percent of them delayed gratification as long as possible. That’s quite a few, but far from 100 percent. Some kids gave up, some tried a little, and some were stalwarts. It’s normal to find variation in behavior. But you can relate variation in delay of gratification to other factors that also differ between children, such as their school performance, drug history, and brain functioning. These factors affected the kids in the new study similar to the way they’d affected the kids in the original delay of gratification studies. When kids learn not to trust an adult experimenter, they give up sooner. That finding, while interesting, says nothing about the importance of delay of gratification. It merely shows that kids are smart not to use their limited mental energy to delay gratification when they may not reap the rewards. Their behavior supports the saying, “Fool me once, shame on you. Fool me twice, shame on me.” The marshmallow studies never sought to identify the Holy Grail of psychological strength. Delay of gratification is one of many factors that contribute to individual, relationship, and societal well-being. Rather than throwing the marshmallows out with the bath water, we should recognize that this new scientific finding has helped identify the nuances of delay of gratification and therefore may help us learn more about living happier, healthier, and more productive lives. ... View more

Originally posted on May 1, 2014. Julian grew up an active child, but those days are long gone. Now he struggles to walk up the stairs. When he walks two city blocks, he takes a break, clenches a light post, and tries to catch his breath. As he looks at passersby, Julian knows what they’re thinking: Obese people are lazy. But according to recent research, those onlookers have it backwards. In a recent UCLA study, researchers wanted to see which comes first, obesity or lack of motivation. They took 32 rats and separated them into two groups. The first group ate a diet designed to make them obese. It mimicked the standard Western diet. The second group ate food that maintained their weight. After six months, the rats completed a fun little motivation task. What happened? A lack of motivation did not cause obesity. It wasn’t until the rats became overweight that their motivation started waning. These findings debunk the myth people become obese because they lack discipline and motivation. Low energy and motivation follow, but do not cause, obesity. ... View more

Originally posted on May 5, 2014. From an early age, I wanted to be an astronaut. I memorized Mercury astronaut missions. I dreamt of using a manned maneurvering unit to glide through space. I cried when the Challenger exploded. I still dream of going to space, but I know it’s a long shot. Still, space exploration captivates me. What will be the biggest obstacle to a successful Mars mission? It won’t be inadequate fuel, faulty aerodynamics, or clunky helmets. Social isolation is the greatest barrier to interplanetary travel. Don’t believe me? Think about the past 520 days of your life (about a year and five months). That’s how long it takes to travel to Mars and return. How many people did you see during that time? How many conversations did you have? Did you attend a sporting event? A play? A worship service? Maybe a loved one was born or passed away. Now wipe those experiences away. Instead, imagine that during this period of your life you lived in cramped quarters with only five other people, no fresh air, and no sunlight. This is not a mere thought experiment. The experiment happened, with funds from the Russian Academy of Sciences. What happened? Quite a bit. In research recently reported in the Proceedings of the National Academy of Sciences, the six volunteer marsonauts completed lots of tasks to keep their minds fresh. They also slept like babies without the daily rigmarole of daily work commutes, grocery shopping, or other daily drivel. Then the guys started sleeping like polar bears in hibernation. Then they started doing less, becoming even more sedentary amidst almost endless boredom. Space is only cool for so long. The good news? They all made it. There weren’t any major scuffles, and the guys probably formed lifelong friendships. They even showed signs of cognitive improvement. But the marsonaut volunteers each handled the prolonged social isolation differently. One of them shifted to a 25-hr sleep-wake schedule, which meant that he was alone (awake or asleep) 20% of the 520 day mock mission. As the researchers sift through their massive data set (to put it in perspective, they measured 4.396 million minutes of sleep!), I’m sure we’ll learn more about the psychological consequences of prolonged social isolation. For now, we can still look into the night sky, find the Red Planet, and dream of people visiting sometime in our generation. We know they’ll sleep well—and a lot. ... View more

Originally posted on May 7, 2014. The Iran and Afghanistan Wars introduced a new and troubling picture on the relationship between traumatic brain injury and mental health. Multiple deployments exposed soldiers to more frequent risks. New combat gear helped them survive blasts. Suicide, substance use, and strained relationships often followed. But according to an Ontario study, we shouldn’t forget another vulnerable group: adolescents who have experienced at least one traumatic brain injury, defined as a head injury that caused either 5 minutes of unconsciousness or an overnight hospital stay. By comparison, the severity of the soldier injuries probably trumped those of the Toronto teens. Yet the two groups experienced similar consequences. In a study of almost 5000 Canadian students Grades 7-12, those who experienced a traumatic brain injury, compared those who didn’t, were nearly three times more likely to attempt suicide. The brain injured adolescents were also more likely to engage in antisocial behavior and experience anxiety and depression. Here is the most stunning statistic of all: roughly 20% of Ontario adolescents have a lifetime history of traumatic brain injury. Part of this makes sense. Think back to when you were a teenager. Perhaps you skateboarded, played soccer, hockey, football, or roughhoused with your siblings. Learning how to drive, you might have been injured in a car accident. Our teenage years are often filled with risk because the teenage brain is hypersensitive to reward. (To watch some videos of a true genius on the topic of the teenage brain, click here). Yet the drive for reward can come at the greatest cost of all. By risking their bodies, adolescents risk their brains. And when that piece of equipment doesn’t run on all cylinders, life becomes more of a slog than a sweet dream. The next time you think of brain injury, think of those who put themselves in harm’s way. For some of us, risk if part of our job. For others, it’s part of our development. For all of us, it’s time to reconsider who needs help.      ... View more

Originally posted on May 9, 2014. The next time you’re facing potential social rejection, what should you do? New evidence suggests a puff of pot reduces the pain of rejection. But before we get to the pot smoking, how did we hatch this idea? Like most ideas, it was formed over an informal conversation. Previously, we had shown that the physical painkiller acetaminophen numbs people to the pain of rejection. Now we wanted to see whether another drug that works through similar brain receptors would also reduce the pain of rejection. It just happened that marijuana fit the bill. In four studies, participants reported how often they smoked marijuana. Next, we measured their feelings of social exclusion or manipulated how socially excluded they felt. Finally, we measured participants’ emotional distress. The four studies yielded a similar pattern: marijuana reduced the pain of rejection. What is the takeaway message? Rejection hurts, and drugs that reduce physical pain also lessen the pain of rejection. Don’t smoke up to prove a point. Just know that rejection is serious. When you’re feeling lonely, reach out to friends before you reach for a roach clip. ... View more

Originally posted May 13, 2014. We might not realize it, but our names hold the key to how much people trust us. Our actual name might not matter. It is how easily you can pronounce a person’s name that counts. Imagine the following scenario. You walk into an auto repair shop to get your car fixed. A smiling man greets you at the door, shakes your hand, and says, “How are you?” You look at his uniform, which has his name printed in an oval patch. It says, “Yvgeny.” Having spent no time in Russia, you struggle to pronounce his name. Would your botched pronunciation affect how much you trusted your would-be mechanic? It would. In a recent investigation, people with easily pronounceable names, versus hard to pronounce names, were rated as less dangerous, more positive, and more trustworthy. The next time you struggle to pronounce someone’s name, give that person a break. We don’t pick the names our parents give us. Should we also give more credit to those who have triumphed despite having hard to pronounce names? Did Quvenzhané Wallis need to do more to earn her Oscar nomination than Naomi Watts did? We’ll never know. Until we do, think of the people you choose to include in your life. We have limited energy and only include a few people in our social networks. Of the ones you chose, did their easy to pronounce names give them an edge? ... View more

Originally posted on May 15, 2014. Each day we face stressors. Our pets get sick, lightning strikes the office, or we miss loved ones. New research identified another stressor lurking in our midst: men. This research, which was reported by the New York Times, showed that rats and mice get stressed out when they’re around men. Even catching a whiff of a men’s t-shirt was enough to raise their stress hormones. The scent of a woman didn’t increase stress. Most men don’t consider themselves stressors. When I walk into a classroom, I tell my students my mission: Motivate Encourage Advocate Learn But these findings suggest that no matter what I do, my maleness may spike their stress levels. The good news is that our bodies adjust. The first day of class might be stressful, especially when you have a male instructor. Over time that stress should wash away. How far can we extrapolate these findings? Although exposure to a single male increases stress that eventually drops off, what if people were constantly bombarded with men? In societies where men outnumber women, would stress levels peak? My next post will answer that question. ... View more

Originally posted on May 16, 2014. Being around men increases stress. Do countries with more man than women have higher stress levels? In my last post, I promised to answer this question. But it’s a harder question than it seems. How do you measure a country’s level of stress? Some organizations, such as Gallup, do an excellent job surveying people around the world. I don’t work at Gallup, nor do I have access to their data. So I had to do the best I could. First, I gathered country gender composition data from our friends at the World Bank. I separated countries according to whether they had a majority of male or female citizens. The average was 50.77% women (standard deviation 1.19; Minimum: 48.19%, Maximum: 54.30%). Of the 74 countries for which data were available, 19 were male-majority and 55 were female-majority. Next, I searched for a good, comprehensive measure of country-level stress. Bloombergmade things easy. They computed a country’s stress score by combining seven factors: Annual Homicide Rate per 100,000 Gross Domestic Product (GDP) per capita Income inequality (Gini coefficient) Corruption (as measured by Transparency International) Unemployment rate Urban air pollution (micrograms per cubic meter) Life expectancy (years at birth) Finally, I compared country-level stress between male-majority and female-majority countries. This would give me an initial answer to my question. What were the results? Countries with more men than women, compared to their female-majority counterparts, had higher levels of stress. Three factors drove the effect: corruption, pollution, and life expectancy. In each case, more men than women equaled a more corrupt, polluted, and shorter lived society. A close fourth, which wasn’t quite statistically significant (p= .063), was Gross Domestic Product per capita. If a country had a male majority (vs. female majority), GDP was lower. These findings offer a novel extension to the finding that being around men, versus women, increases rodent stress. But unlike those careful laboratory experiments, people weren’t randomly assigned to live in male- or female-majority countries. We can’t infer cause and effect. All we can conclude is that when men are present, stress seems to rise instead of fall. ... View more

Originally posted on May 20, 2014. Three years ago, I gained a new appreciation of consciousness. My mom had an accident that caused her brain to bleed. It seemed to rip away her consciousness. As I slept next to her bed before she died, I wondered, “Is she conscious of what’s happening?” New research suggests that the brain can give us a clue. Prior to this research, you had limited options to know if someone had consciousness. You could ask them. That’s easy. But what about those cases, like my mom’s, when a person hasn’t experienced brain death but is still unresponsive? To find out, researchers scanned the brain of a woman who was in a vegetative state. They asked her to imagine playing tennis, along with several other activities. The results, published in Science, made a big splash. Although the woman couldn’t answer the questions, her brain did. When she imagined playing tennis, her brain reacted by increasing blood flow to the motor cortex. She was immobile, but her brain acted as if she was playing on Wimbledon’s Centre Court. To watch a wonderful video of the researcher leading this effort, click here. It might change the way you think about consciousness. I know it helped me. ... View more

Originally posted on May 22, 2014. Runners pop up everywhere. They run alone, in pairs, and in mass hordes through major cities. Running can improve health. But what about extreme running? Is 100 miles too far? I get this question a lot. I run ultramarathons. An ultramarathon is any foot race longer than a standard 26.2 mile (42.2 kilometer) marathon. In the past year, I’ve run nine ultramarathons. This includes two 50 kilometer (31 miles) races, one 60 kilometer race (a little over 37 miles), a six hour timed event where I officially ran 40 miles (I got lost and ran a couple “bonus” miles, too), three 50 mile races, and two 100 mile races. When people learn about my running, they often ask two questions. The first is, “Why do you do that?” I like the challenge, they make me feel good physically and emotionally, and I love the camaraderie. The second question is almost always, “Is that good for you?” Many people think running isn’t good for you. “It’s bad for your knees,” many people tell me. When it comes to extreme running, the possible harm only increases, right? “Didn’t you hear about the ultrarunner, Caballo Blanco, from the book Born to Run? He died while running. That proves it.” Before we rush to judgment, let’s look at the data. When we do that, we’ll find two things. The first is that we don’t really know much. There aren’t many people who run ultramarathons. The sport is growing, but we’re a niche group. In late April, I ran a 100 mile race. 185 people started. Compare that to the most selective American marathon, the Boston Marathon, which in 2014 had 35,671 starters! The second thing we’ll learn is that ultrarunners have pretty good health. In one recent study, ultrarunners, compared to the general population, had better physical health, mental health, and missed fewer days due to illness. They do tend to have more allergies and asthma, which is probably due to wheezing from the gorgeously pollinated trails they traverse. Other research shows that ultrarunners have longer telomeres – DNA strands at the end of chromosomes that often shrink with age. With longer telomeres, ultrarunners may be less vulnerable to disease. So, we now have a better perspective on whether ultrarunning is good for you. You don’t have to run 100 miles to reap the benefits of running. Simply take one more step today than you did yesterday. ... View more

Originally posted on May 27, 2014. Psychology is ripe with history. Unlike many sciences, psychology grips us because we are its main characters. People have more experience with quarrels than with quarks. But one of psychology’s most famous case studies continues to evolve. So, I ask, will the real Phineas Gage please step forward? The name Phineas Gage might not perk up a person’s ears as easily as Freud, Bandura, or Skinner. But the story of Phineas Gage occupies precious real estate in most psychology textbooks. He showed the world that people can survive a major brain trauma. Yet understanding his post-accident life grows fuzzier over time. In a recent article that foreshadows the upcoming book, “The Tale of the Dueling Neurosurgeons,” Sam Stein argues that what we think we know about the most famous name in neuroscience needs historical revision. Did Gage really become a psychopath? Why do people ignore Gage’s major life events, such as when he tried to make a new life in Chile? We’ll never know the true Phineas Gage. The riddle will always be partly unsolved. That isn’t such a bad thing. Sifting through material will inspire new questions—with the hope that they will inform how we understand friends, loved ones, or the many others who have suffered traumatic brain injuries. ... View more

Originally posted on May 29, 2014. How would you like to increase your brainpower? All you need is a 9-volt battery, some mad scientists, and a heaping portion of creativity. So says a slew of recent studies using a noninvasive, neuroscientific technique called transcranial direct current stimulation (tDCS). Think of tDCS as the ultimate symphony conductor. It can pep up certain brain regions by exciting neuronal impulses. But it can also quiet a crowd of neurons by decreasing their firing rate. A 9-volt battery powers the electrodes that rest on people’s scalps, giving people a slight twinge as the equipment increases or decreases their brain activity. In one study, Air Force pilots who received frequent tDCS stimulation, compared with those who didn’t, learned more information in less time. But tDCS isn’t merely a way to learn better. It can help people cope with upsetting situations. In a pair of papers, my colleagues and I showed that stimulating a brain region that aids emotion regulation reduced rejection-related distress and aggression. To succeed, people need some combination of talent, grit, and luck. Should a personal brain zapping machine get added to the list? ... View more