Chapter 16. Psychopathology: Biological Basis of Behavior Disorders

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Richard A. Friedman Jet lag makes everyone miserable. But it makes some people mentally ill. There’s a psychiatric hospital not far from Heathrow Airport that is known for treating bipolar and schizophrenic travelers, some of whom are occasionally found wandering aimlessly through the terminals. A study from the 1980s of 186 of those patients found that those who’d traveled from the west had a higher incidence of mania, while those who’d traveled from the east had a higher incidence of depression. I saw the same thing in one of my patients who suffered from manic depression. When he got depressed after a vacation to Europe, we assumed he was just disappointed about returning to work. But then he had a fun trip out West and returned home in what’s called a hypomanic state: He was expansive, a fount of creative ideas. It was clear that his changes in mood weren’t caused by the vacation blues, but by something else. The problem turned out to be a disruption in his circadian rhythm. He didn’t need drugs; he needed the right doses of sleep and sunlight at the right time. It turns out that that prescription could treat much of what ails us. Clinicians have long known that there is a strong link between sleep, sunlight and mood. Problems sleeping are often a warning sign or a cause of impending depression, and can make people with bipolar disorder manic. Some 15 years ago, Dr. Francesco Benedetti, a psychiatrist in Milan, and colleagues noticed that hospitalized bipolar patients who were assigned to rooms with views of the east were discharged earlier than those with rooms facing the west — presumably because the early morning light had an antidepressant effect. The notion that we can manipulate sleep to treat mental illness has also been around for many years. Back in the late 1960s, a German psychiatrist heard about a woman in Tübingen who was hospitalized for depression and claimed that she normally kept her symptoms in check by taking all-night bike rides. He subsequently demonstrated in a group of depressed patients that a night of complete sleep deprivation produced an immediate, significant improvement in mood in about 60 percent of the group. © 2017 The New York Times Company

Keyword: Biological Rhythms; Schizophrenia
Link ID: 23350 - Posted: 03.13.2017

By Agata Blaszczak-Boxe Recognizing when a friend or colleague feels sad, angry or surprised is key to getting along with others. But a new study suggests that a knack for eavesdropping on feelings may sometimes come with an extra dose of stress. This and other research challenge the prevailing view that emotional intelligence is uniformly beneficial to its bearer. In a study published in the September 2016 issue of Emotion, psychologists Myriam Bechtoldt and Vanessa Schneider of the Frankfurt School of Finance and Management in Germany asked 166 male university students a series of questions to measure their emotional smarts. For example, they showed the students photographs of people's faces and asked them to what extent feelings such as happiness or disgust were being expressed. The students then had to give job talks in front of judges displaying stern facial expressions. The scientists measured concentrations of the stress hormone cortisol in the students' saliva before and after the talk. In students who were rated more emotionally intelligent, the stress measures increased more during the experiment and took longer to go back to baseline. The findings suggest that some people may be too emotionally astute for their own good, says Hillary Anger Elfenbein, a professor of organizational behavior at Washington University in St. Louis, who was not involved in the study. “Sometimes you can be so good at something that it causes trouble,” she notes. Indeed, the study adds to previous research hinting at a dark side of emotional intelligence. A study published in 2002 in Personality and Individual Differences suggested that emotionally perceptive people might be particularly susceptible to feelings of depression and hopelessness. © 2017 Scientific American

Keyword: Emotions; Stress
Link ID: 23326 - Posted: 03.08.2017

By Clare Wilson The repeated thoughts and urges of obsessive compulsive disorder (OCD) may be caused by an inability to learn to distinguish between safe and risky situations. A brain-scanning study has found that the part of the brain that sends out safety signals seems to be less active in people with the condition. People with OCD feel they have to carry out certain actions, such as washing their hands again and again, checking the oven has been turned off, or repeatedly going over religious thoughts. Those worst affected may spend hours every day on these compulsive “rituals”. To find out more about why this happens, Naomi Fineberg of Hertfordshire Partnership University NHS Foundation Trust in the UK and her team trained 78 people to fear a picture of an angry face. The team did it by sometimes giving the volunteers an electric shock to the wrist when they saw the picture while they were lying in an fMRI brain scanner. About half the group had OCD. The team then tried to “detrain” the volunteers, by showing them the same picture many times, but without any shocks. Judging by how much the volunteers sweated in response to seeing the picture, the team found that people without OCD soon learned to stop associating the face with the shock, but people with the condition remained scared. © Copyright Reed Business Information Ltd.

Keyword: OCD - Obsessive Compulsive Disorder; Learning & Memory
Link ID: 23323 - Posted: 03.07.2017

by Laura Sanders Amid a flurry of cabinet appointments and immigration policies, the Trump administration has announced one thing it will not do: pursue policies that protect transgender children in public schools. The Feb. 22 announcement rescinds Obama administration guidelines that, among other protections, allow transgender kids to use bathrooms and participate in sports that correspond with their genders, and to be called by their preferred names and pronouns. In a Feb. 23 news briefing, White House press secretary Sean Spicer said that this is a states’ rights issue. “States should enact laws that reflect the values, principles, and will of the people in their particular state,” he said. “That's it, plain and simple.” But this “plain and simple” move could be quite dangerous, even deadly, science suggests. Transgender children, who are born one biological sex but identify as the other, already face enormous challenges as they move through a society that often doesn’t understand or accept them. Consider this: Nearly half (46.5 percent) of young transgender adults have attempted suicide at some point in their lives, a recent survey of over 2,000 people found. Nearly half. For comparison, the attempted suicide rate among the general U.S. population is estimated to be about 4.6 percent. What’s more, a 2015 study in the Journal of Adolescent Health found that transgender youth are two to three times as likely as their peers to suffer from depression and anxiety disorders, or to attempt suicide or harm themselves. These troublesome stats, based on a sample of 180 transgender children and young adults in Boston ages 12 to 29, applied equally to those who underwent male-to-female transitions and those who underwent female-to-male transitions. © Society for Science & the Public 2000 - 2017.

Keyword: Sexual Behavior; Depression
Link ID: 23297 - Posted: 03.01.2017

By Daniel Barron On January 2, 1979, Dr. Rafael Osheroff was admitted to Chestnut Lodge, an inpatient psychiatric hospital in Maryland. Osheroff had a bustling nephrology practice. He was married with three children, two from a previous marriage. Everything had been going well except his mood. For the previous two years, Osheroff had suffered from bouts of anxiety and depression. Dr. Nathan Kline, a prominent psychopharmacologist in New York City, had begun Osheroff on a tricyclic antidepressant and, according to Kline’s notes—which were later revealed in court—he improved. But then Osheroff decided, against Kline’s advice, to change his dose. He got worse. So much worse that he was brought to Chestnut Lodge. For the next seven months, Osheroff was treated with intensive psychotherapy for narcissistic personality disorder and depression. It didn’t help. He lost 40 pounds, suffered from excruciating insomnia, and began pacing the floor so incessantly that his feet became swollen and blistered. Osheroff’s family, distressed by the progressive unraveling of his mind, hired a psychiatrist in Washington D.C. to intervene. In response, Chestnut Lodge held a clinical case conference yet decided to not change treatment. Importantly, they decided to not begin medications but to continue psychotherapy. They considered themselves “traditional psychiatrists”—practitioners of psychodynamic psychotherapy, the technique used by Sigmund Freud and other pioneers. © 2017 Scientific American

Keyword: Depression; Schizophrenia
Link ID: 23290 - Posted: 02.28.2017

By James Gallagher Health and science reporter, Maps have revealed "hotspots" of schizophrenia and other psychotic illnesses in England, based on the amount of medication prescribed by GPs. The analysis by the University of East London showed North Kesteven, in Lincolnshire, had the highest rates. The lowest rate of schizophrenia prescriptions was in East Dorset. However, explaining the pattern across England is complicated and the research team says the maps pose a lot of questions. They were developed using anonymous prescription records that are collected from doctors' surgeries in England. They record only prescriptions given out by GPs - not the number of patients treated - so hospital treatment is missed in the analysis. Data between October 2015 and September 2016 showed the average number of schizophrenia prescriptions across England was 19 for every 1,000 people. Prof Allan Brimicombe, one of the researchers from UEL, said: "The pattern is not uniformly spread across the country." He suggests this could be due to "environmental effects" such as different rates of drink or drug abuse. Prof Brimicombe told the BBC: "The top one is in the Lincolnshire countryside and there are others in the countryside." © 2017 BBC

Keyword: Schizophrenia
Link ID: 23281 - Posted: 02.25.2017

By Jennifer Couzin-Frankel At least two dozen junior and senior researchers are stuck in scientific limbo after being barred from publishing data collected over a 25-year period at a National Institutes of Health (NIH) lab. The unusual ban follows the firing last summer of veteran neurologist Allen Braun by the National Institute on Deafness and Other Communication Disorders (NIDCD) for what many scientists have told Science are relatively minor, if widespread, violations of his lab’s experimental protocol. Most of the violations, which were unearthed after Braun himself reported a problem, involve the prescreening or vetting of volunteers for brain imaging scans and other experiments on language processing. The fallout from the case was recently chronicled on a blog by one of Braun’s former postdocs, and it highlights a not-uncommon problem across science: the career harm to innocent junior investigators following lab misconduct or accidental violations on the part of senior scientists. But this case, say those familiar with it, is extreme. “We’re truly collateral damage,” says Nan Bernstein Ratner of the University of Maryland in College Park, who researches stuttering. She spent 5 years collaborating with Braun. Now, two of her graduate students have had to shift their master’s theses topics, and an undergraduate she mentored cannot publish a planned paper. “The process has been—you can use this term—surreal.” © 2017 American Association for the Advancement of Science

Keyword: Brain imaging; Stress
Link ID: 23265 - Posted: 02.22.2017

By Esther Landhuis For much of her life Anne Dalton battled depression. She seldom spoke with people. She stayed home a lot. The days dragged on with a sense of “why bother?” for the 61-year-old from New Jersey who used to work at a Wall Street investment firm. After trying more than a dozen combinations of antidepressant drugs to no avail, things got so bad two years ago that Dalton went in for electroconvulsive therapy—in which “basically they shock your brain,” as she puts it. Like Dalton, most of the estimated 16 million U.S. adults who have reported a major depressive episode in the past year find little relief even after several months on antidepressants—a problem that some researchers say may stem from the way mental illness is diagnosed. Objective lab tests can physically confirm heart disease or cancer, but psychiatric conditions are classified somewhat vaguely as clusters of reported symptoms. Doctors consider people clinically depressed if they say they have low mood and meet at least four additional criteria from an overall list of nine. Yet depression can manifest differently from person to person: One might be putting on pounds and sleeping much of the time whereas another might be losing weight, feeling anxious and finding it difficult to sit still, says Conor Liston, a neuroscientist and psychiatrist at Weill Cornell Medical College. “The fact that we lump people together like this has been a big obstacle in understanding the neurobiology of depression,” Liston explains. © 2017 Scientific American,

Keyword: Depression; Brain imaging
Link ID: 23262 - Posted: 02.21.2017

By Nathaniel P. Morris Cardiovascular disease and mental illness are among the top contributors to death and disability in the United States. At first glance, these health conditions seem to lie at opposite ends of the medical spectrum: Treating the heart is often associated with lab draws, imaging and invasive procedures, whereas treating the mind conjures up notions of talk therapy and subjective checklists. Yet researchers are discovering some surprising ties between cardiac health and mental health. These connections have profound implications for patient care, and doctors are paying attention. Depression has become recognized as a major issue for people with heart disease. Studies have found that between 17 and 44 percent of patients with coronary artery disease also have major depression. According to the American Heart Association, people hospitalized for a heart attack are roughly three times as likely as the general population to experience depression. As many as 40 percent of patients undergoing coronary artery bypass surgery suffer from depression. Decades of research suggest these illnesses may actually cause one another. For example, patients with heart disease are often sick and under stressful circumstances, which can foster depressive symptoms. But depression itself is also a risk factor for developing heart disease. Researchers aren’t sure why, but something about being depressed — possibly a mix of factors including inflammatory changes and behavior changes — appears to increase risk of heart disease. © 1996-2017 The Washington Post

Keyword: Depression; Stress
Link ID: 23250 - Posted: 02.18.2017

By Andy Coghlan It’s as if a switch has been flicked. Evidence is mounting that chronic fatigue syndrome (CFS) is caused by the body swapping to less efficient ways of generating energy. Also known as ME or myalgic encephalomyelitis, CFS affects some 250,000 people in the UK. The main symptom is persistent physical and mental exhaustion that doesn’t improve with sleep or rest. It often begins after a mild infection, but its causes are unknown. Some have argued that CFS is a psychological condition, and that it is best treated through strategies like cognitive behavioural therapy. But several lines of investigation are now suggesting that the profound and painful lack of energy seen in the condition could in many cases be due to people losing their ability to burn carbohydrate sugars in the normal way to generate cellular energy. Instead, the cells of people with CFS stop making as much energy from sugar as usual, and start relying more on lower-yielding fuels, such as amino acids and fats. This kind of metabolic switch produces lactate, which can cause pain when it accumulates in muscles. Together, this would explain both the shortness of energy, and why even mild exercise can be exhausting and painful. © Copyright Reed Business Information Ltd.

Keyword: Depression
Link ID: 23226 - Posted: 02.14.2017

By BENEDICT CAREY The number of retirement-age Americans taking at least three psychiatric drugs more than doubled between 2004 and 2013, even though almost half of them had no mental health diagnosis on record, researchers reported on Monday. The new analysis, based on data from doctors’ office visits, suggests that inappropriate prescribing to older people is more common than previously thought. Office visits are a close, if not exact, estimate of underlying patient numbers. The paper appears in the journal JAMA Internal Medicine. Geriatric medical organizations have long warned against overprescribing to older people, who are more susceptible to common side effects of psychotropic drugs, such as dizziness and confusion. For more than 20 years, the American Geriatrics Society has published the so-called Beers Criteria for potentially inappropriate use, listing dozens of drugs and their mutual interactions. In that time, prescription rates of drugs like antidepressants, sleeping pills and painkillers nonetheless generally increased in older people, previous studies have found. The new report captures one important dimension, the rise in so-called polypharmacy — three drugs or more — in primary care, where most of the prescribing happens. Earlier research has found that elderly people are more likely to be on at least one psychiatric drug long term than younger adults, even though the incidence of most mental disorders declines later in life. “I was stunned to see this, that despite all the talk about how polypharmacy is bad for older people, this rate has doubled,” said Dr. Dilip Jeste, a professor of psychiatry and neurosciences at the University of California, San Diego, who was not involved in the new work. © 2017 The New York Times Company

Keyword: Depression; Drug Abuse
Link ID: 23225 - Posted: 02.14.2017

Richard A. Friedman Psychedelics, the fabled enlightenment drugs of the ’60s, are making a comeback — this time as medical treatment. A recent study claimed that psilocybin, a mushroom-derived hallucinogenic, relieves anxiety and depression in people with life-threatening cancer. Anecdotal reports have said similar things about so-called microdoses of LSD. The allure is understandable, given the limits of our treatments for depression and anxiety. About a third of patients with major depression don’t get better, even after several trials of different antidepressants. But I fear that in our desire to combat suffering, we will ignore the potential risks of these drugs, or be seduced by preliminary research that seems promising. This appears to be the case with the new psilocybin study, which has some serious design flaws that cast doubt on the results (and which the authors mention briefly). The study, done at New York University School of Medicine, examined a very small number of people with cancer in a “crossover” design in which each subject served as her own control, sequentially receiving doses of psilocybin and the control drug niacin, in random order. (Another recent study of psilocybin, done at Johns Hopkins University, used a similar crossover design.) Psilocybin, being a hallucinogen, has immediately recognizable mental effects, so subjects would almost certainly know when they were getting it compared with niacin, a vitamin that causes flushing but has no discernible effect on mood or thinking. This makes it hard to know if subjects got better because of the psilocybin, or because of a placebo effect. The design also means that subjects who got psilocybin first could have had a “carry-over effect” from the drug when they received niacin. In other words, they might still have been under the influence, contaminating the control condition. © 2017 The New York Times Company

Keyword: Depression; Drug Abuse
Link ID: 23223 - Posted: 02.14.2017

Patti Neighmond It's tough to be a teenager. Hormones kick in, peer pressures escalate and academic expectations loom large. Kids become more aware of their environment in the teen years — down the block and online. The whole mix of changes can increase stress, anxiety and the risk of depression among all teens, research has long shown. But a recent study published in the journal Pediatrics suggests many more teenage girls in the U.S. may be experiencing major depressive episodes at this age than boys. And the numbers of teens affected took a particularly big jump after 2011, the scientists note, suggesting that the increasing dependence on social media by this age group may be exacerbating the problem. Psychiatrist Ramin Mojtabai and colleagues at Johns Hopkins University Bloomberg School of Public Health wanted to know whether rates of depression among teens had increased over the past decade. They analyzed federal data from interviews with more than 172,000 adolescents. Between 2005 and 2014, the scientists found, rates of depression went up significantly — if extrapolated to all U.S. teens it would work out to about a half million more depressed teens. What's more, three-fourths of those depressed teens in the study were girls. The findings are just the latest in a steady stream of research showing that women of all ages experience higher rates of depression compared to men, says psychologist and author Catherine Steiner-Adair. And no wonder, she says — despite gains in employment, education and salary, women and girls are still "continually bombarded by media messages, dominant culture, humor and even political figures about how they look — no matter how smart, gifted, or passionate they are." © 2017 npr

Keyword: Depression; Development of the Brain
Link ID: 23220 - Posted: 02.13.2017

Bruce Bower A small, poorly understood segment of the population stays mentally healthy from age 11 to 38, a new study of New Zealanders finds. Everyone else encounters either temporary or long-lasting mental disorders. Only 171 of 988 participants, or 17 percent, experienced no anxiety disorders, depression or other mental ailments from late childhood to middle age, researchers report in the February Journal of Abnormal Psychology. Of the rest, half experienced a transient mental disorder, typically just a single bout of depression, anxiety or substance abuse by middle age. “For many, an episode of mental disorder is like influenza, bronchitis, kidney stones, a broken bone or other highly prevalent conditions,” says study coauthor Jonathan Schaefer, a psychologist at Duke University. “Sufferers experience impaired functioning, many seek medical care, but most recover.” The remaining 408 individuals (41 percent) experienced one or more mental disorders that lasted several years or more. Their diagnoses included more severe conditions such as bipolar and psychotic disorders. Researchers analyzed data for individuals born between April 1972 and March 1973 in Dunedin, New Zealand. Each participant’s general health and behavior were assessed 13 times from birth to age 38. Eight mental health assessments occurred from age 11 to 38. |© Society for Science & the Public 2000 - 2016.

Keyword: Depression
Link ID: 23200 - Posted: 02.08.2017

Amy Maxmen The acid tests of 1960s San Francisco have morphed into something quite different in today’s Silicon Valley. Mind-altering trips have given way to subtle productivity boosts purportedly caused by tiny amounts of LSD or other psychedelic drugs. Fans claim that this ‘microdosing’ boosts creativity and concentration, but sceptics doubt that ingesting or inhaling one-tenth of the normal dose could have an effect. Science could soon help to settle the matter. Researchers have finally mapped the 3D structure of LSD in its active state — and the details, published today in Cell1, indicate the key to the chemical’s potency1. Another team reports today in Current Biology2 that it has pinpointed the molecular go-between that creates the perception of deep meaning experienced during acid trips — a feeling that the writer Aldous Huxley once described as “solidarity with the Universe”. “This is what we dreamed of doing when I was a graduate student in the seventies,” says Gavril Pasternak, a pharmacologist at Memorial Sloan Kettering Cancer Center in New York City who has spent decades studying the receptor proteins in the brain that mediate the activity of opioids and psychedelic drugs. “Work like this expands our understanding of how these receptors work.” In 1972, researchers revealed LSD’s shape by mapping the arrangement of atoms in its crystallized form3. But in the decades since, they’ve struggled to reveal the crystal structure of a receptor grasping a molecule of LSD or another psychedelic drug. This active configuration is key to understanding how drugs work, because their action depends on how they cling to molecules in the body. © 2017 Macmillan Publishers Limited,

Keyword: Drug Abuse; Depression
Link ID: 23157 - Posted: 01.27.2017

By Anil Ananthaswamy People with post-traumatic stress disorder often get flashbacks that can be triggered by an innocuous smell or sound. Now a study that linked unrelated memories and separated them again, suggests that one day we may be able to decouple memories and prevent flashbacks in people with PTSD. Individual memories are stored in groups of neurons – an idea first proposed by psychologist Donald Hebb in 1949. Only now are we developing sophisticated techniques for examining these ensembles of neurons. To see whether two independent memories can become linked, Kaoru Inokuchi at the University of Toyama in Japan, and colleagues used a standard method for creating memories in mice. When mice are exposed to pain, they can learn to link this with associated stimuli, a taste, for example. The team trained mice to form two separate fear memories. First, the mice learned to avoid the sugary taste of saccharine. Whenever they licked a bottle filled with saccharine solution, they were injected with lithium chloride, which induces nausea. Disconnecting memories A few days later, the same mice were taught to associate a tone with a mild electric shock. This caused the mice to freeze whenever they heard it, even if it wasn’t followed with a shock. They remembered the tone as a traumatic experience. © Copyright Reed Business Information Ltd.

Keyword: Learning & Memory; Stress
Link ID: 23156 - Posted: 01.27.2017

By Nathaniel P. Morris In the 20th century, the deinstitutionalization of mental health care took patients out of long-term psychiatric facilities with the aim that they might return to the community and lead more fulfilling lives. But in our rush to shut down America’s asylums, we failed to set up adequate outpatient services for the mentally ill, who now often fend for themselves on the streets or behind bars. According to recent surveys, the number of state psychiatric beds has fallen from over 550,000 in 1955 to fewer than 38,000 in 2016. Meanwhile, research conducted by the Treatment Advocacy Center estimates over 355,000 inmates in America’s prisons and jails suffered from severe mental illness in 2012. Last year, a report by the Department of Housing and Urban Development found that over 100,000 Americans who experienced homelessness also suffered from severe mental illness. Mental health advocates point to a number of failures, such as limited funding for outpatient care and a lack of political foresight, that may have led to this situation. Yet emerging community-based approaches to mental health care are providing hope for the severely mentally ill—as well as some constraints. Court-ordered care for patients with severe mental illness, known as assisted outpatient treatment or AOT, is spreading nationwide. In December, President Obama signed into law the landmark 21st Century Cures Act, bipartisan legislation that bolsters funding for medical research and reshapes approval processes for drugs and medical devices. The law also supports a number of mental health reforms, including millions in federal incentives for states to develop AOT. © 2017 Scientific American

Keyword: Depression; Schizophrenia
Link ID: 23144 - Posted: 01.25.2017

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.

Keyword: Stress; Drug Abuse
Link ID: 23129 - Posted: 01.21.2017

Claudia Dreifus Geneticists tell us that somewhere between 1 and 5 percent of the genome of modern Europeans and Asians consists of DNA inherited from Neanderthals, our prehistoric cousins. At Vanderbilt University, John Anthony Capra, an evolutionary genomics professor, has been combining high-powered computation and a medical records databank to learn what a Neanderthal heritage — even a fractional one — might mean for people today. We spoke for two hours when Dr. Capra, 35, recently passed through New York City. An edited and condensed version of the conversation follows. Q. Let’s begin with an indiscreet question. How did contemporary people come to have Neanderthal DNA on their genomes? A. We hypothesize that roughly 50,000 years ago, when the ancestors of modern humans migrated out of Africa and into Eurasia, they encountered Neanderthals. Matings must have occurred then. And later. One reason we deduce this is because the descendants of those who remained in Africa — present day Africans — don’t have Neanderthal DNA. What does that mean for people who have it? At my lab, we’ve been doing genetic testing on the blood samples of 28,000 patients at Vanderbilt and eight other medical centers across the country. Computers help us pinpoint where on the human genome this Neanderthal DNA is, and we run that against information from the patients’ anonymized medical records. We’re looking for associations. What we’ve been finding is that Neanderthal DNA has a subtle influence on risk for disease. It affects our immune system and how we respond to different immune challenges. It affects our skin. You’re slightly more prone to a condition where you can get scaly lesions after extreme sun exposure. There’s an increased risk for blood clots and tobacco addiction. To our surprise, it appears that some Neanderthal DNA can increase the risk for depression; however, there are other Neanderthal bits that decrease the risk. Roughly 1 to 2 percent of one’s risk for depression is determined by Neanderthal DNA. It all depends on where on the genome it’s located. © 2017 The New York Times Company

Keyword: Evolution; Depression
Link ID: 23128 - Posted: 01.21.2017

About 11 per cent of Canadians aged 15 to 24 experienced depression at some point in their lives, and fewer than half of them sought professional help for a mental health condition over the previous year, according to Statistics Canada. The information was released Wednesday in the agency's Health Reports, and is based on data from the 2012 Canadian Community Health Survey Mental Health. The report was based on 4,031 respondents aged 15 to 24, which when extrapolated represents more than 4.4 million young people. Canadians 15 to 24 years old had a higher rate of depression than any other age group. Suicide is the second leading cause of death (after accidents), accounting for nearly a quarter of deaths in the 15-24 category, Statistics Canada said. An estimated 14 per cent of respondents reported having had suicidal thoughts at some point in their lives. The figure includes six per cent having that thought in the past 12 months. As well, 3.5 per cent had attempted suicide, according to the data. Report author Leanne Findlay said the findings confirm people with depression or suicidal thoughts are increasingly likely to seek professional help. Young people in the study were more likely to turn to friends or family, and when they did, generally felt they received a lot or some help. Factors such as perceived ability to deal with stress and "negative social interactions" — for instance, feeling others were angry with you — were related to depression and suicidal thoughts. Symptoms of depression include feeling sad or having trouble sleeping that last two weeks or more, Findlay said. "Knowledge of these risk and protective factors may facilitate early intervention," Findlay concluded. ©2017 CBC/Radio-Canada.

Keyword: Depression; Development of the Brain
Link ID: 23121 - Posted: 01.19.2017