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By Laura Sanders Changes in the brains of mice that were isolated as young pups may help explain the profound behavioral problems of severely neglected children. The mouse experiments suggest that neglect during a specific developmental window irreversibly stunts brain development, researchers report in the Sept. 14 Science. Over the last decade, researchers have catalogued brain deficits and behavioral problems in Romanian orphans who were raised in bare-bones environments with little social stimulation. Many of these children display hyperactivity, impulsivity and compulsive behavior such as arm flapping. Although superficially friendly, these kids have trouble forming meaningful relationships. By studying mice that had been isolated early in life, researchers led by Gabriel Corfas of Children’s Hospital Boston and Harvard Medical School hoped to uncover how social deprivation can affect the developing brain. After the mice had weaned, the researchers put them into one of three environments: One was a deluxe suite, enriched with fresh toys every other day and populated by friends of similar ages, one was a standard laboratory cage holding four mice, and one was a holding cell for total isolation. After two weeks, mice in the deluxe suite and the regular cage showed no abnormalities in their behavior or brains. But mice that were isolated showed big changes. These animals were socially stunted, showing less signs of exploratory behavior and a diminished working memory. What’s more, the researchers uncovered stunted development in the brain’s white matter, which helps nerve cells communicate. © Society for Science & the Public 2000 - 2012

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 13: Memory, Learning, and Development
Link ID: 17259 - Posted: 09.15.2012

By Laura Sanders A single four-month deployment to Afghanistan is associated with brain changes and diminished attention, Dutch scientists report. Most changes went away a year and a half after returning from combat, suggesting that the brain can largely heal itself — and that longer breaks between combat tours might be a good idea. The study, which focused on healthy Dutch soldiers, reveals how the brain responds to stress outside of a laboratory, says clinical neuroscientist Rajita Sinha of the Yale University School of Medicine. “It’s a nice way to start looking at natural high levels of stress we experience as humans,” she says. Although the soldiers came back mentally and physically healthy, in Afghanistan they had fought, come under enemy fire and seen their fellow soldiers and civilians wounded or dead. Researchers led by Guido van Wingen of the University of Amsterdam conducted brain scans while the soldiers performed a lab test that required them to hold several numbers in their memory simultaneously. Initially, the researchers found no brain differences between 33 soldiers who were about to be deployed for the first time and 26 who were still in training. Nor were there differences in a lab task that required intense concentration for several minutes. But the story changed after some soldiers experienced combat, the team reports online September 4 in the Proceedings of the National Academy of Sciences. © Society for Science & the Public 2000 - 2012

Related chapters from BP7e: Chapter 16: Psychopathology: Biological Basis of Behavior Disorders; Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 12: Psychopathology: Biological Basis of Behavioral Disorders; Chapter 15: Language and Our Divided Brain
Link ID: 17232 - Posted: 09.07.2012

The stresses of poverty — such as crowded conditions, financial worry, and lack of adequate child care — lead to impaired learning ability in children from impoverished backgrounds, according to a theory by a researcher funded by the National Institutes of Health. The theory is based on several years of studies matching stress hormone levels to behavioral and school readiness test results in young children from impoverished backgrounds. Further, the theory holds, finding ways to reduce stress in the home and school environment could improve children's well being and allow them to be more successful academically. High levels of stress hormones influence the developing circuitry of children's brains, inhibiting such higher cognitive functions such as planning, impulse and emotional control, and attention. Known collectively as executive functions, these mental abilities are important for academic success. Clancy Blair, Ph.D., of New York University, concludes that this altered stress response and its effect on executive function helps to explain one way in which poverty affects children’s development of school readiness skills and later classroom performance. Although poverty is considered a major source of stress, the findings also suggest that other sources of stress may affect children in all income groups — for example, from divorce, harsh parenting, or struggles with a learning disability.

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 13: Memory, Learning, and Development
Link ID: 17217 - Posted: 08.29.2012

By Chelsea Conaboy Brian Sullivan, a former Army bomb technician, quit treatment for post-traumatic stress when, he said, doctors began pushing him to take medications he didn’t want. His symptoms, however, did not quit. Traffic jams made the 42-year-old Foxborough native anxious. Sullivan couldn’t go into a crowded mall. And he was haunted by the memory of a man who approached him while he was working to disable an improvised explosive device during one of two deployments to Afghanistan, he said. Sullivan faced a choice: Shoot, or risk that the man was a suicide bomber. He didn’t fire, but the stress stuck with him. Last year, Sullivan, who now lives in Virginia, began using a smartphone application developed by the Department of Defense to guide him through breathing exercises when his anxiety began to build. The same agency launched another app earlier this year for veterans to use while in a particular kind of therapy, revisiting difficult memories with a professional. Sullivan became curious, and this summer returned to treatment. Ten years ago, the resources available to veterans with PTSD who were unwilling or unable, because of geography or other factors, to be treated by a therapist were limited. Researchers are developing technologies to reach people like Sullivan wherever they are, putting tools directly into their hands through programs online and on their smartphones. © 2012 NY Times Co.

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 16: Psychopathology: Biological Basis of Behavior Disorders
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 12: Psychopathology: Biological Basis of Behavioral Disorders
Link ID: 17206 - Posted: 08.27.2012

by Michael Slezak Despite the fact that women live longer than men, their brains seems to age faster. The reason? Possibly a more stressful life. When people age, some genes become more active while others become less so. In the human brain, these changes can be observed through the "transcriptome" – a set of RNA molecules that indicate the activity of genes within a population of cells. When Mehmet Somel, a computational biologist at the University of California, Berkeley, and his colleagues compared the transcriptome of 55 male and female brains of different ages, they were surprised to find that the pattern of gene activation and deactivation that occurs with ageing appeared to progress faster in women than in men. This was particularly apparent in an area of the pre-frontal cortex. "This was just the opposite of what we'd originally expected," says Somel, who was at the Shanghai Institutes for Biological Sciences in China when he did the research. He says that given the fact that females have a longer lifespan, they had expected to see slower or later ageing-related changes in their brain. "But it fits everyday observations on ageing. Not all organs within an individual age at the same rate," he says. Somel's team compared the expression of more than 13,000 genes in four brain regions. In one region – the superior frontal gyrus – they found 667 genes that were expressed differently in men and women during ageing. Of those, 98 per cent were skewed towards faster ageing in women. Some of these gene changes have previously been linked to general cognitive decline and degenerative disease. © Copyright Reed Business Information Ltd

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 8: Hormones and Sex
Link ID: 17100 - Posted: 07.28.2012

By Linda Searing, THE QUESTION Might fear of childbirth contribute to a longer labor? THIS STUDY involved 2,206 women who were pregnant with one child and had planned to have a vaginal birth. Based on their answers to questions about childbirth that they gave when they were 32 weeks pregnant, 165 women (about 8 percent) were classified as fearful. Those women spent more time in labor than did those who were not fearful: eight hours, on average, compared with 6 hours 28 minutes. Also, emergency Caesarean deliveries and births that involved the use of forceps or other instruments were more common among fearful women. Overall, 25 percent of women who feared childbirth delivered vaginally without intervention, compared with 44 percent of those who were not afraid. WHO MAY BE AFFECTED? Pregnant women. Worries related to childbirth generally focus on pain and how to cope with it. Medical experts say the pain varies from woman to woman and depends in part on a woman’s anatomy, the size and position of her baby and the strength of contractions as well as her emotional state and attitude. CAVEATS Some data in the study came from the women’s responses on questionnaires. FIND THIS STUDY June 27 online issue of BJOG: an International Journal of Obstetrics and Gynaecology (www.bjog.org). © 1996-2012 The Washington Post

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 16997 - Posted: 07.03.2012

By Scicurious When I saw all the headlines going around focused on this paper, I KNEW I had to check it out. Heck, sometimes Twitter is faster than my Pubmed alerts! “Chronic Stress, Mood Disorders Linked In New Research On Rats“, “Stress Blocks Gene That Guards Brain Against Depression” The link between stress, dysregulations of the hypothalamic pituitary adrenal axis, and depressive-like symptoms in animals and depression in humans is actually really well known. We can put down our “stress linked to depression” headlines, now. In fact, other papers from the same lab as this paper have shown the link between stress and depression many, many times. We know stress correlates with depression and that stress can produce depressive like symptoms in animals. But this paper? This paper is very new, and very cool! Not because it shows a link between stress and depression. This new finding, the gene neuritin, joins a group of things linking stress and depression, including BDNF, glucocorticoid receptors, serotonin 1A receptors, and many more. This is not the first link between stress and depression and it won’t be the last. But it IS a cool finding. Because it presents us with a new antidepressant target, and we can always use one of those. All of the clinical antidepressants that are currently on the market work through one specific mechanism: they increase the levels of certain neurotransmitters in your brain. © 2012 Scientific American,

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 16: Psychopathology: Biological Basis of Behavior Disorders
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 12: Psychopathology: Biological Basis of Behavioral Disorders
Link ID: 16996 - Posted: 07.03.2012

Adults who were subjected to physical punishment such as spanking as children are more likely to experience mental disorders, say Canadian researchers who encourage other forms of discipline. Monday's issue of the journal Pediatrics includes a study on the proportion of illnesses such as depression, anxiety, alcohol and drug abuse as well as personality disorders that may be attributable to physical punishment. Positive reinforcement techniques have more evidence backing them than physical punishment.Positive reinforcement techniques have more evidence backing them than physical punishment. (Evan Vucci/Associated Press) Physical punishment was defined as pushing, grabbing, shoving, slapping and hitting in the absence of more severe maltreatment of a child through physical abuse, sexual abuse, emotional abuse, physical neglect, emotional neglect or exposure to intimate partner violence. "It definitely points to the direction that physical punishment should not be used on children of any age and we need to be considering that when we're thinking about policy and programs so we can protect children from potentially harmful outcomes," said study author Tracie Afifi, who is in the department of community health sciences at the University of Manitoba. Afifi hopes the findings from the study that involved more than 34,000 U.S. adults will make parents think twice about spanking. © CBC 2012

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 13: Memory, Learning, and Development
Link ID: 16990 - Posted: 07.02.2012

by Beverly Purdy The Medivac helicopter made a noisy descent to the landing pad at University Medical Center in Salt Lake City. The patient on board was on the final leg of a long journey home from South Africa. Jeremy Clark, an ambitious 23-year-old college graduate, had been on a Mormon mission in Johannesburg when he awoke one day unable to move his legs. He was briefly hospitalized there, but the South African doctors could not explain his sudden paralysis and found no evidence of injury or infection, so he was transferred back to the States by air ambulance. Medics wheeled Jeremy to the neurology ward, where I was waiting. They said he had been about three weeks into his two-year commitment in South Africa when one morning he did not show up for his assignment, nor did he answer his 
phone. Someone finally went to his apartment and found him lying there, immobilized. “He’s been like this for a week, doctor,” the medic told me. “He hasn’t spoken since this happened.” As the neurology resident, I needed to test Jeremy for a number of disorders, including multiple sclerosis (ms); myasthenia gravis, a neuromuscular autoimmune disease that causes varying degrees of muscle weakness; Guillain-Barré syndrome, an acute condition associated with progressive muscle weakness and paralysis; and stroke. I would also have to perform a lumbar puncture to collect fluid from around the brain and inside the spinal cord to rule out infection. Although his symptoms didn’t quite support the diagnosis, I also wondered if he could have been exposed to a toxin that can cause paralysis, such as botulism or tetanus. © 2012, Kalmbach Publishing Co.

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 16989 - Posted: 07.02.2012

by Gisela Telis Stress really does mess with your mind. A new study has found that chronic stress can create many of the brain changes associated with mood disorders by blocking a gene called neuritin—and that boosting the gene's activity can protect the brain from those disorders. The results provide new insight into the mechanisms behind depression, anxiety, and bipolar disorder, and could offer researchers a novel target for drugs to treat those conditions. Research has shown that mood disorders take a toll on patients' brains as well as on their lives. Postmortem studies and brain scans have revealed that the hippocampus (the brain's memory center) can shrink and atrophy in people with a history of depression and other mood disorders. People who live with mood disorders are also known to have low levels of brain-derived neurotrophic factor (BDNF), a growth factor that keeps neurons healthy. They also have low activity in the neuritin gene, which codes for a protein of the same name that may protect the brain's plasticity: its ability to reorganize and change in response to new experiences. Ronald Duman, a neurobiologist at Yale University, and colleagues wondered if the poorly understood neuritin might play an important -- and heretofore overlooked -- role in depression and other mood disorders. They induced depression in a group of rats by subjecting them to chronic, unpredictable stress. Depriving them of food and play, isolating them, and switching around their day/night cycles for about 3 weeks left the rats with little interest in feeding or enjoying a sweetened drink. The rats also gave up and became immobile instead of swimming when placed in a tub of water—another measure of rodent depression. © 2010 American Association for the Advancement of Science

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 16: Psychopathology: Biological Basis of Behavior Disorders
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 12: Psychopathology: Biological Basis of Behavioral Disorders
Link ID: 16971 - Posted: 06.26.2012

By AMANDA SCHAFFER In recent decades, there have been few new treatments for people with stubbornly high blood pressure. Exercise and a low-sodium diet, along with such stalwart drugs as diuretics, ACE inhibitors and beta-blockers, have made up the standard regimens. But these efforts fail in a surprising number of patients. On three or more medications, many still suffer from uncontrolled hypertension and with it a heightened risk of heart attack and stroke. Now, doctors are experimenting with an innovative but drastic new approach that may help lessen the danger in patients for whom nothing else works. During the procedure, called renal denervation, a physician threads a catheter into the arteries leading to the kidney, then delivers pulses of radio-frequency energy that interrupt the signaling in nerves to and from that organ. The damage to the nerves is probably permanent, although no one is certain. Small clinical trials, conducted mainly outside the United States, have suggested that in combination with drugs, renal denervation may help to reduce high blood pressure in patients with so-called treatment-resistant disease. The treatment is already available in Australia and Europe. The largest randomized controlled trial to date is now under way in the United States. It is sponsored by Medtronic, which hopes to win Food and Drug Administration approval for a specialized catheter and generator used in the procedure. © 2012 The New York Times Company

Related chapters from BP7e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 11: Emotions, Aggression, and Stress
Link ID: 16903 - Posted: 06.12.2012

by Jeanna Bryner, LiveScience Managing Editor Intense and lasting stress may deliver a blow to a kid's noggin, say researchers who found that a brain area linked to memory was smaller in children who had experienced chronic stress compared with their less-strained counterparts. The brain differences also bore out in cognitive ability, with those children with highly stressful lives performing poorer than other kids on spatial memory tests. The highly stressed children also had more trouble with tests of short-term memory, including tasks such as finding a token in a series of boxes, the researchers said. "All families experience some stress, so it is important to note that effects were found for high levels of stress," study researcher Jamie Hanson, a psychology graduate student at the University of Wisconsin-Madison, told LiveScience, adding that some extreme examples would include family members falling victim to violent crimes or the chronic illness of a child or other family member. The research, detailed in the June 6 issue of the Journal of Neuroscience, adds to other evidence of the impacts of stress, with one recent study showing that children exposed to multiple instances of violence age faster on a cellular level. Another past study suggested childhood stress could actually take years off an individual's life. The team was inspired by work in animals that has found a link between stress and brain changes, particularly in the prefrontal cortex, which is involved in working memory, or the part of your memory that's available for quick recall. © 2012 Discovery Communications, LLC.

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 13: Memory, Learning, and Development
Link ID: 16893 - Posted: 06.09.2012

by Michael Balter Many studies in humans and animals suggest that chronic stress is bad for one’s health, in part because it suppresses the immune system. But nearly 30 years of data on wild baboons shows that top-ranking males, despite showing signs of increased stress, recover more quickly than low-ranking baboons from wounds and illness. The results may help explain why some people escape from the negative effects of stress while others do not. Most studies in humans have shown a clear correlation between higher socioeconomic status and lower risk of death or illness from stress-related diseases such as heart attacks and diabetes. Some of the most famous of these are the so-called Whitehall studies of the British Civil Service, which showed that death and illness rates decreased in a step-wise fashion the higher an employee was on the service’s 6-grade pay and responsibility scale. These and other studies also have found that being at the bottom of the totem pole leads to greater stress as a result of increased work loads and time pressures, as well as more job insecurity. But studies of animals, especially other primates, have shown that the relationship between stress and status largely depends on the social organization of the species in question. For example, in species such as baboons that have rigid social rankings and hierarchies, with so-called alpha males dominating other males and females over extended periods of time, it can apparently be more stressful at the top. In a study reported last year in Science, a team that included ecologist Jeanne Altmann of Princeton University revealed that baboon alpha males had the highest levels of glucocorticoid hormones, such as cortisol, as well as testosterone in their feces, indicators that they were under greater stress than lower-ranking individuals. © 2010 American Association for the Advancement of Science.

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 8: Hormones and Sex
Link ID: 16827 - Posted: 05.22.2012

by Greg Miller Autopsies of four U.S. military veterans who served in Iraq and Afghanistan reveal features of the same neurodegenerative disease found previously in athletes, researchers report. Experiments with mice suggest that the underlying mechanisms may be similar. In the past 10 years, the widely reported suicides and accidental deaths of professional football players and other athletes—such as that of Junior Seau earlier this month -- have sparked inquiries into whether even seemingly minor blows to the head can cause personality changes, dementia, and brain degeneration later in life. Autopsies of dozens of former players have revealed a condition known as chronic traumatic encephalopathy (CTE). Its hallmark is the abnormal accumulation of a protein called tau. Many of the athletes diagnosed with CTE on autopsy (currently the only definitive test) had a history of problems with anger, rash and risky decision-making, impairments of memory and attention, and alcohol or drug abuse. Clinicians and researchers working with troops returning from Iraq and Afghanistan have seen similar symptoms. The new study, led by Lee Goldstein, a physician-scientist who focuses on neurodegenerative disease at Boston University, and Ann McKee, a neuropathologist at the Bedford Veterans Affairs Medical Center in Massachusetts, ties these troublesome threads together. McKee examined the brains of four veterans, men between the ages of 22 and 45, who suffered from various combinations of cognitive, emotional, and impulse-control problems before dying from suicide or other causes. © 2010 American Association for the Advancement of Science.

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 15: Language and Our Divided Brain
Link ID: 16809 - Posted: 05.17.2012

By Laura Sanders A certain genetic signature gives some people the ability to form stronger memories. But that edge also has a dark side: increased risk of post-traumatic stress disorder. Although the genetic effect is small, the results help scientists better understand the link between especially powerful memories and sensitivity to past trauma. Scientists led by neuroscientist Dominique de Quervain of the University of Basel in Switzerland looked at how genetic differences related to a memory task. A population of 723 healthy young Swiss adults viewed 72 photographs. After a 10-minute wait, the volunteers were asked to remember as many images as possible. Volunteers who could remember more pictures carried a particular DNA signature in at least one copy of a gene that encodes protein kinase C alpha. In animal studies, this protein has been shown to play a role in the formation of emotional memories. The volunteers’ heightened recall was true for disturbing, pleasant and neutral pictures. Further evidence came from brain scans performed in a different group of Swiss people. While viewing the pictures, people with the genetic signature had stronger brain activation in parts of the prefrontal cortex compared with those who lacked the genetic feature, the researchers report online the week of May 14 in the Proceedings of the National Academy of Sciences. © Society for Science & the Public 2000 - 2012

Related chapters from BP7e: Chapter 17: Learning and Memory; Chapter 16: Psychopathology: Biological Basis of Behavior Disorders
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 12: Psychopathology: Biological Basis of Behavioral Disorders
Link ID: 16792 - Posted: 05.15.2012

By Neil Bowdler Health reporter, BBC News A trial has begun of a portable brain-cooling device which could enhance the survival prospects of cardiac patients. Ground-based cars in the service of the charity London's Air Ambulance are the first in the UK to carry the Rhinochill machine. Larger brain-cooling devices are already used in UK hospitals on cardiac and stroke patients to aid recovery. But cooling the body earlier in the field, during resuscitation, could save more lives, early research suggests. "We know quite well that if you're cooled after your heart attack, it can not only mean that your chances of surviving are greatly increased, but your chances of surviving without brain damage are too," Dr Richard Lyon, a registrar with London's Air Ambulance, told BBC News. "For the last 10 years or so, the big thrust has been to cool you as quickly as possible, but usually after you get delivered to hospital, after your heart has been restarted. "What we're doing is bringing everything much further forward - starting this brain-cooling process while CPR is still being carried out in the field." BBC © 2012

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 15: Language and Our Divided Brain; Chapter 11: Emotions, Aggression, and Stress
Link ID: 16741 - Posted: 05.03.2012

By Robin Nixon LONDON — A seemingly trivial task – playing a particular video game – may lessen flashbacks and other psychological symptoms following a traumatic event, according to research presented here at the British Psychology Society Annual Conference. Researchers are now corroborating what some trauma sufferers have happened upon by chance: Focusing on a highly engaging visual-spatial task, such as playing video games, may significantly reduce the occurrence of flashbacks, the mental images concerning the trauma that intrude on the sufferer afterward. Flashbacks are considered by some to be the central hub of symptoms associated with post-traumatic stress disorder (PTSD), researchers Lalitha Iyadurai and Ella James of Oxford University explained to LiveScience. They are invasive, unpredictable distress signals that can make everyday activities difficult. The jarring mental images also may trigger or exacerbate other symptoms associated with PTSD, including irritability, anger, poor concentration and sleep disorders. [Top 10 Spooky Sleep Disorders] Reducing the occurrence of flashbacks is therefore likely to relieve post-traumatic suffering while leaving the actual memories of the trauma in place, they said. Iyadurai stressed the new research does not suggest a video game can instantly cure PTSD, but that it does suggests alternative treatments for the symptoms. © 2012 Scientific American

Related chapters from BP7e: Chapter 16: Psychopathology: Biological Basis of Behavior Disorders; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 12: Psychopathology: Biological Basis of Behavioral Disorders; Chapter 11: Emotions, Aggression, and Stress
Link ID: 16711 - Posted: 04.26.2012

by Katherine Rowland Traumatic experiences in early life can leave emotional scars. But a new study suggests that violence in childhood may leave a genetic mark as well. Researchers have found that children who are physically abused and bullied tend to have shorter telomeres—structures at the tips of chromosomes whose shrinkage has been linked to aging and disease. Telomeres prevent DNA strands from unravelling, much like the plastic aglets on a shoelace. When cells divide, these structures grow shorter, limiting the number of times a cell can reproduce. For this reason, telomeres may reflect biological age. Research has found associations between stress and accelerated telomere loss, and shortened telomeres correlate with several health problems, including diabetes, dementia, and fatigue. But the connection between telomere length and health and longevity is far from clear. "There's a lot of doubt in the field," notes Joao Passos, a cellular aging specialist at Newcastle University in the United Kingdom who was not involved in the research. "For as many studies that show telomere length as a good predictor of health outcomes, there are as many that find no relationship." Also unclear is whether childhood stress can affect telomere length. Almost all recent work on the topic has used retrospective data—that is, adults' recollections about their past. The new study examined children who were under stress to determine if they have shorter telomeres. © 2010 American Association for the Advancement of Science

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 13: Memory, Learning, and Development
Link ID: 16709 - Posted: 04.25.2012

By Stephani Sutherland If you have ever jumped at a loud noise and felt an adrenaline rush, you have experienced the effects of corticotropin-releasing hormone (CRH). In the body, this hormone triggers the familiar fight-or-flight response—racing heart, shortness of breath, sweaty palms. In the brain, however, it acts as a chemical messenger, playing a role in anxiety and depression. That role, a new study suggests, is more complex than anyone expected. Because animal research from the past decade found that CRH contributes to anxiety and depression, drugs were developed that would block its actions in the brain. Clinical trials of these anti­anxiety and antidepressant drugs in human patients, however, have been disappointing. The new study, published last September in Science, shows why. Jan M. Deussing, a molecular biologist at the Max Planck Institute of Psychiatry in Munich, and his colleagues genetically altered mice so that some of their brain cells would be unable to detect the presence of CRH because they lacked the proper receptors. When the receptors were missing from neurons that produce the neurotransmitter glutamate, the mice displayed less anxiety, as expected. Yet when the receptors were missing from neurons that produce dopamine, the mice became more anxious. These two different neuron types, when interacting with CRH, “have exactly opposite effects in terms of anxiety-related behavior,” Deussing says. Be­cause the unsuccessful drugs limited the amount of the hormone available to all types of neurons, they ended up blocking its actions at neurons that both produce and prevent anxiety. The finding reaf­firms scientists’ growing understanding that mood disorders do not result from a simple chemical imbalance—too much or too little of one neurotransmitter—but rather from subtle changes in many systems in the brain. “The network is much more complex than we thought before,” Deussing says. © 2012 Scientific American

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 8: Hormones and Sex
Link ID: 16635 - Posted: 04.12.2012

By Emma Seppala What's the difference between noticing the rapid beat of a popular song on the radio and noticing the rapid rate of your heart when you see your crush? Between noticing the smell of fresh baked bread and noticing that you're out of breath? Both require attention. However, the direction of that attention differs: it is either turned outward, as in the case of noticing a stop sign or a tap on your shoulder, or turned inward, as in the case of feeling full or feeling love. Scientists have long held that attention – regardless to what – involves mostly the prefrontal cortex, that frontal region of the brain responsible for complex thought and unique to humans and advanced mammals. A recent study by Norman Farb from the University of Toronto published in Cerebral Cortex, however, suggests a radically new view: there are different ways of paying attention. While the prefrontal cortex may indeed be specialized for attending to external information, older and more buried parts of the brain including the “insula” and “posterior cingulate cortex” appear to be specialized in observing our internal landscape. Most of us prioritize externally oriented attention. When we think of attention, we often think of focusing on something outside of ourselves. We "pay attention" to work, the TV, our partner, traffic, or anything that engages our senses. However, a whole other world exists that most of us are far less aware of: an internal world, with its varied landscape of emotions, feelings, and sensations. Yet it is often the internal world that determines whether we are having a good day or not, whether we are happy or unhappy. That’s why we can feel angry despite beautiful surroundings or feel perfectly happy despite being stuck in traffics. For this reason perhaps, this newly discovered pathway of attention may hold the key to greater well-being. © 2012 Scientific American

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 14: Attention and Consciousness
Link ID: 16614 - Posted: 04.05.2012