Chapter 15. Emotions, Aggression, and Stress
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By NICHOLAS BAKALAR Psychological distress may increase your chances of dying from cancer. Researchers interviewed 163,363 adults in England and Scotland using well-validated questionnaires on general and mental health. They followed the population in 16 studies conducted between 1994 and 2008. After controlling for age, smoking, physical activity and other factors, they found that compared with those with the lowest scores on depression and anxiety, those with the highest had higher rates of cancer death. The associations were particularly strong for colon and rectal, prostate, pancreatic and esophageal cancers, and for leukemia. In instances of colorectal and prostate cancer, they found a “dose-response” effect: the greater the distress, the greater the likelihood of death from those cancers. People might have had undiagnosed cancer at the start of the study, which would affect their mood, so the researchers accounted for this possibility by doing an analysis that excluded study members who died of cancer in the first five years. The results were largely the same. The study, in BMJ, is observational so cannot determine cause and effect, and it depended in part on self-reports. “The extent to which these associations could be causal,” the authors write, “requires further testing with alternative study designs.” © 2017 The New York Times Company
By Mitch Leslie When we have food poisoning, the last thing we want to do is eat. But in mice, a microbe that causes this ailment actually increases appetite, a new study reveals. Researchers say they might be able to use the same trick to increase eating in cancer patients and old folks, who often lose their desire for food. “I think it’s a fantastic paper,” says immunophysiologist Keith Kelley of the University of Illinois in Urbana, who wasn’t connected to the study. The researchers deserve praise for combining approaches from several disciplines such as microbiology, neurobiology, and immunology to draw a surprising conclusion, he says. “It’s the way disease responses should be investigated.” Some of the symptoms you endure when you are ill, such as lethargy and fever, are actually good for you. Lolling on the couch all day, for instance, saves energy for your immune cells. But the picture is more complex for another of these so-called sickness behaviors—reduced appetite. Animal studies have found that eating less seems to improve the odds of surviving some infections, perhaps because it robs the invading microbes of key nutrients, but in other cases the loss of appetite often proves fatal. © 2017 American Association for the Advancement of Science
By GRETCHEN REYNOLDS When people get up and move, even a little, they tend to be happier than when they are still, according to an interesting new study that used cellphone data to track activities and moods. In general, the researchers found, people who move are more content than people who sit. There already is considerable evidence that physical activity is linked to psychological health. Epidemiological studies have found, for example, that people who exercise or otherwise are active typically are less prone to depression and anxiety than sedentary people. But many of these studies focused only on negative moods. They often also relied on people recalling how they had felt and how much they had moved or sat in the previous week or month, with little objective data to support these recollections. For the new study, which was published this month in PLoS One, researchers at the University of Cambridge in England decided to try a different approach. They would look, they decided, at correlations between movement and happiness, that most positive of emotions. In addition, they would look at what people reported about their activity and compare it with objective measures of movement. To accomplish these goals, they first developed a special app for Android phones. Available free on the Google app store and ultimately downloaded by more than 10,000 men and women, it was advertised as helping people to understand how lifestyle choices, such as physical activity, might affect people’s moods. (The app, which is no longer available for download, opened with a permission form explaining to people that the data they entered would be used for academic research.) The app randomly sent requests to people throughout the day, asking them to enter an estimation of their current mood by answering questions and also using grids in which they would place a dot showing whether they felt more stressed or relaxed, depressed or excited, and so on. © 2017 The New York Times Company
What are you like? A look at your brain may tell you. A study has found a link between some elements of brain structure and certain personality traits. The study involved scanning the brains of 500 volunteers, and assessing their personalities in terms of five traits – neuroticism, openness, extraversion, agreeableness, and conscientiousness. The researchers focused on the structure of the cortex, the outer layer of the brain. They found that in people who are more neurotic and prone to mood changes, the cortex tends to be thicker and less wrinkly. People who appear more open – for example, curious and creative – show the opposite pattern. More mature The link between structure and personality may help explain how we mature as we get older. Folds and wrinkles are thought to increase the surface area of the brain, but make the cortex thinner. The cortex continues to stretch and fold throughout childhood and adolescence, and into adulthood. As we grow up, people generally become less neurotic, and more conscientious and agreeable. “Our work supports the notion that personality is, to some degree, associated with brain maturation,” says Roberta Riccelli, at Magna Graecia University in Catanzaro, Italy. Journal reference: Social Cognitive and Affective Neuroscience © Copyright Reed Business Information Ltd.
Joseph Palamar On Nov. 30 the FDA approved a Phase III clinical trial to confirm the effectiveness of treating post-traumatic stress disorder (PTSD) with MDMA, also known as Ecstasy. This news appeared in headlines throughout the world, as it represents an important – yet somewhat unorthodox – advance in PTSD treatment. However, the media have largely been referring to Ecstasy – the street name for this drug – as the treatment in this trial, rather than MDMA (3,4-methylenedioxymethamphetamine). This can lead to misunderstanding, as recreational Ecstasy use is a highly stigmatized behavior. Using this terminology may further misconceptions about the study drug and its uses. While Ecstasy is in fact a common street name for MDMA, what we call Ecstasy has changed dramatically since it became a prevalent recreational drug. Ecstasy now has a very different meaning – socially and pharmacologically. It is understandable why the media have referred to this drug as Ecstasy rather than MDMA. Not only has much of the public at least heard of Ecstasy (and would not recognize MDMA), but this also increases shock value and readership. But referring to a therapeutic drug by its street name (such as Ecstasy) is misleading – especially since MDMA is known to be among the most popular illicit drugs used at nightclubs and dance festivals. This leads some to assume that street drugs are being promoted and provided to patients, perhaps in a reckless manner. © 2010–2017, The Conversation US, Inc.
Jonathan Sadowsky Carrie Fisher’s ashes are in an urn designed to look like a Prozac pill. It’s fitting that in death she continues to be both brash and wryly funny about a treatment for depression. The public grief over Carrie Fisher’s death was not only for an actress who played one of the most iconic roles in film history. It was also for one who spoke with wit and courage about her struggle with mental illness. In a way, the fearless General Leia Organa on screen was not much of an act. Carrie Fisher at a screening of ‘Catastrophe’ at the Tribeca Film Festival in April 2016. PBG/AAD/STAR MAX/IPx via AP Fisher’s bravery, though, was not just in fighting the stigma of her illness, but also in declaring in her memoir “Shockaholic” her voluntary use of a stigmatized treatment: electroconvulsive therapy (ECT), often known as shock treatment. Many critics have portrayed ECT as a form of medical abuse, and depictions in film and television are usually scary. Yet many psychiatrists, and more importantly, patients, consider it to be a safe and effective treatment for severe depression and bipolar disorder. Few medical treatments have such disparate images. I am a historian of psychiatry, and I have published a book on the history of ECT. I had, like many people, been exposed only to the frightening images of ECT, and I grew interested in the history of the treatment after learning how many clinicians and patients consider it a valuable treatment. My book asks the question: Why has this treatment been so controversial? © 2010–2017, The Conversation US, Inc.
Link ID: 23102 - Posted: 01.14.2017
By LISA SANDERS, M.D. “You don’t look well,” the man at the gas station told the older woman in the car. He’d known her for years, always thinking of her as a lively, robust woman. But that day she looked pale and tired. Her sharp blue eyes seemed dim. She gave a feeble smile. “I don’t feel well at all,” she told him. There’s an urgent-care clinic just up the street, he said. Could she make it there? She was nearly 45 minutes away from her home in Halifax, Nova Scotia. Stopping just up the street seemed a much better option. At the clinic, the doctor took one look at her, put a blood pressure cuff around her arm and told her assistant to call an ambulance. The rest of the day was a blur. The woman remembers being bundled onto a stretcher and one of the E.M.T.s saying her blood pressure was very low. It was an odd thing to hear, because her blood pressure was usually high enough to require three medications. She was taken to the emergency room at the Queen Elizabeth II Health Sciences Center in Halifax. She remembers being fussed over — having blood drawn, receiving intravenous fluids, feeling sticky snaps being placed on her chest that connected her to a continuous heart monitor. She had been a nurse for many years when she was younger, yet seeing herself at the center of these familiar activities was strange. A blood test indicated that there may have been damage to her heart. The doctor told her she was having a heart attack, she recalls. You’ve got the wrong patient, she thought to herself. Sure, she had a little high blood pressure, a little asthma, a little back pain. But problems with her heart? Never. The patient used a cane, but she had no difficulty getting up on the exam table — an important test of mobility. © 2017 The New York Times Company
Keyword: Hormones & Behavior
Link ID: 23101 - Posted: 01.14.2017
Jon Hamilton Mice that kill at the flip of a switch may reveal how hunting behavior evolved hundreds of millions of years ago. The mice became aggressive predators when two sets of neurons in the amygdala were activated with laser light, a team reported Thursday in the journal Cell. "The animals become very efficient in hunting," says Ivan de Araujo, an associate professor of psychiatry at Yale University and an associate fellow at The John B. Pierce Laboratory in New Haven. "They pursue the prey [a live cricket] faster and they are more capable of capturing and killing it." Activating the neurons even caused the mice to attack inanimate objects, including sticks, bottle caps and an insectlike toy. "The animals intensively bite the toy and use their forepaws in an attempt to kill it," De Araujo says. But the aggressive behavior is reserved for prey. Mice didn't attack each other, even when both sets of neurons were activated. The results hint at how the brain changed hundreds of millions of years ago when the first animals with jaws began to appear. This new ability to pursue and kill prey "must have influenced the way the brain is wired up in a major way," De Araujo says. Specifically, the brain needed to develop hunting circuits that would precisely coordinate the movements of a predator's jaw and neck. "This is a very complex and demanding task," De Araujo says. © 2017 npr
Link ID: 23099 - Posted: 01.13.2017
Being stressed out increases our risk of heart disease and stroke, and the key to how to counter it may lie in calming the brain, a new medical study suggests. Psychological stress has long been considered a source of sickness. But personal stress levels are difficult to measure and there isn't direct evidence of the link, even though population studies finger stress as a risk factor for cardiovascular disease just like smoking and hypertension. "I think that this relatively vague or insufficient link reduced our enthusiasm of taking stress seriously as an important risk factor," said Dr. Ahmed Tawakol, a cardiologist at Massachusetts General Hospital in Boston. Tawakol led a study published in Wednesday's online issue of The Lancet that sheds light on how the amygdala — a key part of the brain that is more active during emotional, stressful times — is linked to a greater risk of cardiovascular disease such as heart attacks and strokes. The researchers gave 293 patients aged 30 or older without cardiovascular disease PET/CT brain imaging scans, mainly for cancer screening and followed them over time. After an average of nearly four years, activity in the amygdala was significantly associated with cardiovascular events such as heart attacks, heart failure and strokes, after taking other factors into account. People with more amygdala activity also tended to suffer the events sooner, Tawakol said. ©2017 CBC/Radio-Canada.
Link ID: 23087 - Posted: 01.12.2017
By Virginia Morell We often say the same sweet, nonsensical things to our dogs that we say to our babies—and in almost the same slow, high-pitched voice. Now, scientists have shown that puppies find our pooch-directed speech exciting, whereas older dogs are somewhat indifferent. The findings show, for the first time, that young dogs respond to this way of talking, and that it may help them learn words—as such talk does with human babies. To find out how dogs reacted to human speech, Nicolas Mathevon, a bioacoustician at the University of Lyon in Saint Étienne, France, and his colleagues first recorded the voices of 30 women as they looked at a dog’s photograph and read from a script, “Hi! Hello cutie! Who’s a good boy? Come here! Good boy! Yes! Come here sweetie pie! What a good boy!” (The scientists were afraid the women would ad lib if they spoke to a real dog.) The women also repeated the passage to a person. When the scientists compared the human- and dog-directed speech, they found that, as expected, the women spoke in distinctive, high-pitched, sing-song tones to the pooches—but not the humans. “It didn’t matter if it was a puppy or an adult dog,” Mathevon says. But the women did speak at an even higher pitch when looking at puppy photos. Next, the researchers played these recordings in short trials with 10 puppies and 10 adult dogs at a New York City animal shelter and videotaped their responses. Nine of the puppies reacted strongly, barking and running toward the loudspeaker even when the recording had been made for an older dog, the team reports today in the Proceedings of the Royal Society B. Some even bent toward the loudspeaker in a play bow, a pose meant to initiate horseplay, suggesting they may regard dog-directed speech as “an invitation to play,” Mathevon says. © 2017 American Association for the Advancement of Science.
Anouchka Grose Dannii Minogue has admitted to using Botox at difficult times in her life in a subconscious attempt to mask her feelings. Not only might she literally have been disabling her capacity to frown, she may also have been acting things out on her body in order to fend off her own emotions. Is America developing a ‘crack-like addiction’ to Botox beauty? Read more It’s about time someone said it. As a working therapist I have occasionally noticed my female patients’ faces change quite noticeably from week to week, but no one has ever spoken to me about what was making this happen. Cosmetic treatments, and the difficult thoughts and feelings that might make someone undergo them, are apparently one of the hardest things to talk about. On the one hand perhaps these treatments are so normalised that they do not seem worth discussing in therapy – a new study in the US shows that young women using Botox has risen by 41% since 2011 – but on the other you probably wouldn’t spend hundreds of pounds on something that carried serious health risks if you weren’t feeling pretty worried about your appearance. Doing stuff to your face is like the sunny side of self-harm; you might try it in order to short-circuit anxiety or sadness, but the end result is supposedly regeneration rather than damage. Still, nothing signals underlying unhappiness and self-loathing more than a pumped-up, frozen physiognomy. In that sense, it’s a socially acceptable form of wound. © 2017 Guardian News and Media Limited
Link ID: 23078 - Posted: 01.10.2017
By Andy Coghlan Is the fabled “cuddle hormone” really a “warmone”? Oxytocin levels surge in troops of chimpanzees preparing for conflict with rival groups to defend or expand their territory. The finding is at odds with the prevailing image of oxytocin as something that helps strengthen bonds between parent and infant, or foster friendships. But given its capacity to strengthen loyalty, oxytocin could also be a warmonger hormone that helps chimps galvanise and cooperate against a common enemy. Catherine Crockford of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and her colleagues monitored two rival groups of chimpanzees in the Taï National Park in Ivory Coast, each containing five males and five females, for prolonged periods between October 2013 and May 2015. Thanks to trust built up between the team and the chimps, the team could safely track and video the groups – even during conflict, observing at close quarters what was happening. Crucially, the team was also able to pipette up fresh samples from soil when chimps urinated. The samples revealed that oxytocin levels surge in the mammals whenever the chimps on either side prepared for confrontation, or when either group took the risk of venturing near or into rival-held territories. These surges dwarfed the oxytocin levels seen during activities such as grooming, collaborative hunting for monkey prey or food sharing. © Copyright Reed Business Information Ltd.
Hannah Devlin Science correspondent People living near a busy road have an increased risk of dementia, according to research that adds to concerns about the impact of air pollution on human health. Roughly one in 10 cases of Alzheimer’s in urban areas could be associated with living amid heavy traffic, the study estimated – although the research stopped short of showing that exposure to exhaust fumes causes neurodegeneration. Hong Chen, the scientist who led the work at Public Health Ontario, said: “Increasing population growth and urbanisation has placed many people close to heavy traffic, and with widespread exposure to traffic and growing rates of dementia, even a modest effect from near-road exposure could pose a large public health burden.” Previously, scientists have linked air pollution and traffic noise to reduced density of white matter (the brain’s connective tissue) and lower cognition. A recent study suggested that magnetic nano-particles from air pollution can make their way into brain tissue. The latest study, published in The Lancet, found that those who live closest to major traffic arteries were up to 12% more likely to be diagnosed with dementia – a small but significant increase in risk. The study, which tracked roughly 6.6 million people for more than a decade, could not determine whether pollution is directly harmful to the brain. The increased dementia risk could also be a knock-on effect of respiratory and cardiac problems caused by traffic fumes or due to other unhealthy life-style factors associated with living in built-up urban environments. © 2017 Guardian News and Media Limited
By LESLEY ALDERMAN Here’s a New Year’s challenge for the mind: Make this the year that you quiet all those negative thoughts swirling around your brain. All humans have a tendency to be a bit more like Eeyore than Tigger, to ruminate more on bad experiences than positive ones. It’s an evolutionary adaptation that helps us avoid danger and react quickly in a crisis. But constant negativity can also get in the way of happiness, add to our stress and worry level and ultimately damage our health. And some people are more prone to negative thinking than others. Thinking styles can be genetic or the result of childhood experiences, said Judith Beck, a psychologist and the president of the Beck Institute for Cognitive Behavior Therapy in Bala Cynwyd, Pa. Children may develop negative thinking habits if they have been teased or bullied, or experienced blatant trauma or abuse. Women, overall, are also more likely to ruminate than men, according to a 2013 study. “We were built to overlearn from negative experiences, but under learn from positive ones,” said Rick Hanson, a psychologist and senior fellow at the Greater Good Science Center at the University of California, Berkeley. But with practice you can learn to disrupt and tame negative cycles. The first step to stopping negative thoughts is a surprising one. Don’t try to stop them. If you are obsessing about a lost promotion at work or the results of the presidential election, whatever you do, don’t tell yourself, “I have to stop thinking about this.” “Worry and obsession get worse when you try to control your thoughts,” Dr. Beck said. Instead, notice that you are in a negative cycle and own it. Tell yourself, “I’m obsessing about my bad review.” Or “I’m obsessing about the election.” © 2017 The New York Times Company
By Nicole Mortillaro Post-traumatic stress disorder can be a debilitating condition. It's estimated that it affects nearly one in 10 Canadian veterans who served in Afghanistan. Now, there's promising research that could lead to the treatment of the disorder. Following a particularly traumatic event — one where there is the serious threat of death or a circumstance that was overwhelming — we often exhibit physical symptoms immediately. But the effects in our brains actually take some time to form. That's why symptoms of PTSD — reliving an event, nightmares, anxiety — don't show up until some time later. Research has shown that, after such an event, the hippocampus — which is important in dealing with emotions and memory — shrinks, while our amygdala — also important to memory and emotions — becomes hyperactive. In earlier research, Sumantra Chattarji from the National Centre for Biological Sciences (NCBS) and the Institute for Stem Cell Biology and Regenerative Medicine (inStem), in Bangalore, India, discovered that traumatic events cause new nerve connections to form in the amygdala, which also causes hyperactivity. This plays a crucial role in people dealing with post-traumatic stress disorder. Chattarji has been studying changes in the brain after traumatic events for more than a decade. In an earlier study, he concluded that a single stress event had no immediate event on the amygdala of rats. However, 10 days later, the rats exhibited increased anxiety. There were even changes to the brain, and, in particular the amygdala. So Chattarji set out to see if there was a way to prevent these changes. Post-traumatic stress disorder can seriously affect those who have served in the military. New research may help to one day prevent that. (Shamil Zhumatov/Reuters) The new research focused on a particular cell receptor in the brain, called N-Methyl-D-Aspartate Receptor (NMDA-R), which is crucial in forming memories. ©2016 CBC/Radio-Canada.
Mo Costandi The rhythm of breathing co-ordinates electrical activity across a network of brain regions associated with smell, memory, and emotions, and can enhance their functioning, according to a new study by researchers at Northwestern University. The findings, published in the Journal of Neuroscience, suggest that breathing does not merely supply oxygen to the brain and body, but may also organise the activity of populations of cells within multiple brain regions to help orchestrate complex behaviours. Nearly 75 years ago, the British physiologist Edgar Adrian used electrodes to record brain activity in hedgehogs, and found that brain waves in the olfactory system were closely coupled to breathing, with their size and frequency being directly related to the speed at which air moves through the nose. Since then, this same activity has been observed in the olfactory bulb and other brain regions of rats, mice and other small animals, but until now it has not been investigated in humans. In this new study, a research team led by Christina Zelano recorded electrical activity directly from the surface of the brain in seven patients being evaluated for surgery to treat drug-resistant temporal lobe epilepsy, focusing on three brain regions: the piriform cortex, which processes smell information from the olfactory bulbs, the hippocampus, which is critical for memory formation, and the amygdala, which plays an important role in emotional processing. At the same time, they monitored the patients’ respiratory rates with either pressure sensors or an abdominal breathing belt. The researchers found that slow brain wave oscillations in the piriform cortex, and higher frequency brain waves in the hippocampus and amygdala, were synchronised with the rate of natural, spontaneous breathing. Importantly, though, the brain wave oscillations in all three regions were most highly synchronised immediately after the patients breathed in, but less so while they were breathing out. And when the patients were asked to divert breathing to their mouths, the researchers observed a significant decrease in brain wave coupling. © 2016 Guardian News and Media Limited
Link ID: 23017 - Posted: 12.23.2016
By James Gallagher Health and science reporter, BBC News website A drug that alters the immune system has been described as "big news" and a "landmark" in treating multiple sclerosis, doctors and charities say. Trials, published in the New England Journal of Medicine, suggest the drug can slow damage to the brain in two forms of MS. Ocrelizumab is the first drug shown to work in the primary progressive form of the disease. The drug is being reviewed for use in the US and Europe. MS is caused by a rogue immune system mistaking part of the brain for a hostile invader and attacking it. It destroys the protective coating that wraps round nerves called the myelin sheath. The sheath also acts like wire insulation to help electrical signals travel down the nerve. Damage to the sheath prevents nerves from working correctly and means messages struggle to get from the brain to the body. This leads to symptoms like having difficulty walking, fatigue and blurred vision. The disease can either just get worse, known as primary progressive MS, or come in waves of disease and recovery, known as relapsing remitting MS. Both are incurable, although there are treatments for the second state. 'Change treatment' Ocrelizumab kills a part of the immune system - called B cells - which are involved in the assault on the myelin sheath. In 732 patients with progressive MS, the percentage of patients that had deteriorated fell from 39% without treatment to 33% with ocrelizumab . Patients taking the drug also scored better on the time needed to walk 25 feet and had less brain loss detected on scans. In 1,656 patients with relapsing remitting, the relapse rate with ocrelizumab was half that of using another drug. © 2016 BBC
Dhruv Khullar My patient and I both knew he was dying. Not the long kind of dying that stretches on for months or years. He would die today. Maybe tomorrow. And if not tomorrow, the next day. Was there someone I should call? Someone he wanted to see? Not a one, he told me. No immediate family. No close friends. He had a niece down South, maybe, but they hadn’t spoken in years. For me, the sadness of his death was surpassed only by the sadness of his solitude. I wondered whether his isolation was a driving force of his premature death, not just an unhappy circumstance. Every day I see variations at both the beginning and end of life: a young man abandoned by friends as he struggles with opioid addiction; an older woman getting by on tea and toast, living in filth, no longer able to clean her cluttered apartment. In these moments, it seems the only thing worse than suffering a serious illness is suffering it alone. Social isolation is a growing epidemic — one that’s increasingly recognized as having dire physical, mental and emotional consequences. Since the 1980s, the percentage of American adults who say they’re lonely has doubled from 20 percent to 40 percent. About one-third of Americans older than 65 now live alone, and half of those over 85 do. People in poorer health — especially those with mood disorders like anxiety and depression — are more likely to feel lonely. Those without a college education are the least likely to have someone they can talk to about important personal matters. © 2016 The New York Times Company
Link ID: 23003 - Posted: 12.22.2016
By Kate Baggaley In American schools, bullying is like the dark cousin to prom, student elections, or football practice: Maybe you weren’t involved, but you knew that someone, somewhere was. Five years ago, President Obama spoke against this inevitability at the White House Conference on Bullying Prevention. “With big ears and the name that I have, I wasn’t immune. I didn’t emerge unscathed,” he said. “But because it’s something that happens a lot, and it’s something that’s always been around, sometimes we’ve turned a blind eye to the problem.” We know that we shouldn’t turn a blind eye: Research shows that bullying is corrosive to children’s mental health and well-being, with consequences ranging from trouble sleeping and skipping school to psychiatric problems, such as depression or psychosis, self-harm, and suicide. But the damage doesn’t stop there. You can’t just close the door on these experiences, says Ellen Walser deLara, a family therapist and professor of social work at Syracuse University, who has interviewed more than 800 people age 18 to 65 about the lasting effects of bullying. Over the years, deLara has seen a distinctive pattern emerge in adults who were intensely bullied. In her new book, Bullying Scars, she introduces a name for the set of symptoms she often encounters: adult post-bullying syndrome, or APBS. DeLara estimates that more than a third of the adults she’s spoken to who were bullied have this syndrome. She stresses that APBS is a description, not a diagnosis—she isn’t seeking to have APBS classified as a psychiatric disorder. “It needs considerably more research and other researchers to look at it to make sure that this is what we’re seeing,” deLara says.
By DANIEL A. YUDKIN and JAY VAN BAVEL During the first presidential debate, Hillary Clinton argued that “implicit bias is a problem for everyone, not just police.” Her comment moved to the forefront of public conversation an issue that scientists have been studying for decades: namely, that even well-meaning people frequently harbor hidden prejudices against members of other racial groups. Studies have shown that these subtle biases are widespread and associated with discrimination in legal, economic and organizational settings. Critics of this notion, however, protest what they see as a character smear — a suggestion that everybody, deep down, is racist. Vice President-elect Mike Pence has said that an “accusation of implicit bias” in cases where a white police officer shoots a black civilian serves to “demean law enforcement.” Writing in National Review, David French claimed that the concept of implicit bias lets people “indict entire communities as bigoted.” But implicit bias is not about bigotry per se. As new research from our laboratory suggests, implicit bias is grounded in a basic human tendency to divide the social world into groups. In other words, what may appear as an example of tacit racism may actually be a manifestation of a broader propensity to think in terms of “us versus them” — a prejudice that can apply, say, to fans of a different sports team. This doesn’t make the effects of implicit bias any less worrisome, but it does mean people should be less defensive about it. Furthermore, our research gives cause for optimism: Implicit bias can be overcome with rational deliberation. In a series of experiments whose results were published in The Journal of Experimental Psychology: General, we set out to determine how severely people would punish someone for stealing. Our interest was in whether a perpetrator’s membership in a particular group would influence the severity of the punishment he or she received. © 2016 The New York Times Company