October 15, 2008, 5:42 PM CT

A walk in the park improves attention in children with ADHD

For children with Attention Deficit Hyperactivity Disorder (ADHD) tasks that require concentration such as doing homework or taking a test can be very difficult. A simple, inexpensive remedy may be a "dose of nature".

A study conducted at the University of Illinois shows that children with ADHD demonstrate greater attention after a 20-minute walk in a park than after a similar walk in a downtown area or a residential neighborhood.

The study, conducted by child environment and behavior scientists Andrea Faber Taylor and Frances E. Kuo was published in a recent issue of the Journal of Attention Disorders

"From our prior research, we knew there might be a link between spending time in nature and reduced ADHD symptoms," said Faber Taylor. "So to confirm that link we conducted a study in which we took children on walks in three different settings one particularly "green" and two less "green" and kept everything about the walks as similar as possible".

Some children took the "green" walk first; others took it second or last. After each walk, an experimenter who didn't know which walk the child had been on tested their attention using a standard neurocognitive test called Digit Span Backwards, in which a series of numbers are said aloud and the child recites them backwards. It's a test in which practice doesn't improve your score......... Posted by: JoAnn      Read more         Source

October 15, 2008, 5:38 PM CT

High-school social skills predict better earnings than test scores

Ten years after graduation, high-school students who had been rated as conscientious and cooperative by their teachers were earning more than classmates who had similar test scores but fewer social skills, said a new University of Illinois study.

The study's findings challenge the idea that racial, ethnic, and socioeconomic gaps in educational attainment and earnings can be narrowed solely by emphasizing cognitive skills, said Christy Lleras, a University of Illinois assistant professor of human and community development.

"It's important to note that good schools do more than teach reading, writing, and math. They socialize students and provide the kinds of learning opportunities that help them to become good citizens and to be successful in the labor market," she said.

"Unless we address the differences in school climates and curriculum that foster good work habits and other social skills, we're doing a huge disservice to low-income kids who may be entering the labor market right after high school, particularly in our increasingly service-oriented economy," Lleras added.

She cited responses to employer surveys that stress the need for workers who can get along well with each other and get along well with the public.

The U of I study analyzed data from the National Educational Longitudinal Study, which followed a diverse group of 11,000 tenth graders for 10 years, tracking not only their scores on standard achievement tests but teacher appraisals of such qualities as the students' work habits, their ability to relate well to peers, and their participation in extracurricular activities, a proxy for the ability to interact well with both students and adults......... Posted by: JoAnn      Read more         Source

October 8, 2008, 9:39 PM CT

Circadian clock may be critical for remembering

The circadian rhythm that quietly pulses inside us all, guiding our daily cycle from sleep to wakefulness and back to sleep again, may be doing much more than just that simple metronomic task, as per Stanford researchers.

Working with Siberian hamsters, biologist Norman Ruby has shown that having a functioning circadian system is critical to the hamsters' ability to remember what they have learned. Without it, he said, "They can't remember anything".

Though not known for their academic prowess, Siberian hamsters nonetheless normally develop what amounts to street smarts about their environment, as do all animals. But hamsters whose circadian system was disabled by a new technique Ruby and colleagues developed consistently failed to demonstrate the same evidence of remembering their environment as hamsters with normally functioning circadian systems.

Until now, it has never been shown that the circadian system is crucial to learning and memory. The finding has implications for diseases that include problems with learning or memory deficits, such as Down syndrome or Alzheimer's disease. The work is described in a paper published Oct. 1 online in the early edition of the Proceedings of the National Academy of Sciences Ruby is lead author on the paper. Siberian hamsters, also known as dwarf hamsters, are about the size of a mouse......... Posted by: Daniel      Read more         Source

October 7, 2008, 10:07 PM CT

Compassion meditation to psychological stress

Data from a new study suggests that individuals who engage in compassion meditation may benefit by reductions in inflammatory and behavioral responses to stress that have been associated with depression and many medical illnesses. The study's findings are published online at www.sciencedirect.com and in the medical journal Psychoneuroendocrinology

"While much attention has been paid to meditation practices that emphasize calming the mind, improving focused attention or developing mindfulness, less is known about meditation practices designed to specifically foster compassion," says Geshe Lobsang Tenzin Negi, PhD, who designed and taught the meditation program used in the study. Negi is senior lecturer in the Department of Religion, the co-director of Emory Collaborative for Contemplative Studies and president and spiritual director of Drepung Loseling Monastery, Inc.

This study focused on the effect of compassion meditation on inflammatory, neuroendocrine and behavioral responses to psychosocial stress, and reviewed the degree to which engagement in meditation practice influenced stress reactivity.

"Our findings suggest that meditation practices designed to foster compassion may impact physiological pathways that are modulated by stress and are relevant to disease," explains Charles L. Raison, MD, clinical director of the Mind-Body Program, Emory University's Department of Psychiatry and Behavioral Sciences, Emory School of Medicine, and a lead author on the study......... Posted by: JoAnn      Read more         Source

October 1, 2008, 9:31 PM CT

Getting help for depression and anxiety

As per the Mood Disorder Society of Canada, about 1.3 million Canadians suffer from depression.

University of Alberta researcher Ian Colman says most people are not getting the type of therapy they need.

Colman, an assistant professor from the School of Public Health, and his research team decided to perform a study to see the long term effects of taking antidepressants or anti-anxiety medications.

The team studied a group of 200 people who were diagnosed with either depression or anxiety. Of that group, 45 were on medication.

The group of 200 had their mental health assessed in 1989 through a series of questions in a survey asking about their illness and what, if any, therapys they were on. Ten years later the group took a similar questionnaire.

Colman says they were surprised to find those who were not using antidepressants or anti-anxiety medications were three times more likely to be suffering from depression or anxiety 10 years later.

"This is a significant find," said Colman. "What this tells us is that, if people get treated initially, they are less likely to have a relapse in the future. This could be a significant benefit, not only for the patient but also for the health-care system as it's estimated the economic costs in Canada linked to depression are $14 billion per year"......... Posted by: JoAnn      Read more         Source

October 1, 2008, 9:30 PM CT

Television Viewing and Aggression

The effect of media violence on behavior is not only an interesting psychological question but is also a relevant public policy and public health issue. Eventhough a number of studies have been conducted examining the link between violence on TV and aggressive behavior, most of these studies have overlooked several other potentially significant factors, including the dramatic context of the violence and the type of violence depicted as well as the race and ethnicity of the viewers.

In a new study appearing in the recent issue of Perspecitves on Psychological Science, a journal of the Association for Psychological Science, psychology experts Seymour Feshbach from the University of California, Los Angeles and June Tangney from George Mason University investigated the effect that exposure to violent TV programs has on negative behavior in children from different ethnic backgrounds. To investigate this connection, the psychology experts conducted a study that reviewed TV viewing habits, intelligence, and behavior in 4th, 5th and 6th grade children. To assess these qualities, the children's parents and teachers completed behavioral questionnaires detailing the children's aggression, delinquency and cruelty. The children took IQ tests and completed surveys indicating the TV programs (which were later categorized as violent or non-violent by the researchers) they had watched during a seven day time period......... Posted by: JoAnn      Read more         Source

October 1, 2008, 8:23 PM CT

PTSD impacts veterans' well-being

Deployed peacekeeping veterans with post traumatic stress disorder (PTSD) have significant impairments in health-related quality of life as per research by Dr. J. Donald Richardson of The University of Western Ontario and his co-investigators.

The research, published this month in the Canadian Journal of Psychiatry, found anxiety disorders such as PTSD are linked to impaired emotional well-being, and this applies just as much to peacekeeping veterans as to combat veterans. "This finding is important to clinicians working with the newer generation of veterans, as it stresses the importance of including measures of quality of life when evaluating veterans to better address their rehabilitation needs," says Dr. Richardson. "It is not enough to measure symptom changes with therapy; we need to objectively asses if therapy is improving their quality of life and how they are functioning in their community".

Richardson is a consultant psychiatry expert with the Operational Stress Injury Clinic at Parkwood Hospital, part of St. Joseph's Health Care, London and a psychiatry professor with the Schulich School of Medicine & Dentistry at Western. His team studied 125 male, deployed Canadian Forces peacekeeping veterans who were referred for a psychiatric assessment. The average age of these men was 41, and they averaged 16 years of military service. The most common military theatre in which they served were the Balkan states (Bosnia, Croatia, former Yugoslavia, and Kosovo), with 83 per cent having exposure to combat or a war zone......... Posted by: JoAnn      Read more         Source

September 29, 2008, 10:31 PM CT

Second-hand smoke may trigger nicotine dependence

Montreal, September 29, 2008 Parents who smoke cigarettes around their kids in cars and homes beware second-hand smoke may trigger symptoms of nicotine dependence in children. The findings appear in the September edition of the journal Addictive Behaviors in a joint study from nine Canadian institutions.

"Increased exposure to second-hand smoke, both in cars and homes, was linked to an increased likelihood of children reporting nicotine dependence symptoms, even though these children had never smoked," says Dr. Jennifer O'Loughlin, senior author of the study, a professor at the Universit de Montral's Department of Social and Preventive Medicine and a researcher at the Centre Hospitalier de l'Universit de Montral.

"These findings support the need for public health interventions that promote non-smoking in the presence of children, and uphold policies to restrict smoking in vehicles when children are present," adds Dr. O'Loughlin, who collaborated with scientists from the Universit de Sherbrooke, the Universit de Moncton, the University of British Columbia, McGill University, Concordia University and the Institut national de sant publique du Qubec.

Study participants were recruited from 29 Quebec schools as part of AdoQuest, a cohort investigation that measures tobacco use and other health-compromising behaviours. Some 1,800 children aged 10 to 12 years old, from all socioeconomic levels, were asked to complete questionnaires on their health and behaviours. Scientists also asked questions about symptoms of nicotine dependence and exposure to second-hand smoke......... Posted by: Janet      Read more         Source

September 28, 2008, 8:42 PM CT

'Hub' of fear memory formation identified in brain cells

A protein mandatory for the earliest steps in embryonic development also plays a key role in solidifying fear memories in the brains of adult animals, researchers have revealed. An apparent "hub" for changes in the connections between brain cells, beta-catenin could be a potential target for drugs to enhance or interfere with memory formation.

The results are published online this week and appear in the recent issue of Nature Neuroscience

The protein beta-catenin acts like a Velcro strap, fastening cells' internal skeletons to proteins on their external membranes that connect them with other cells. In species ranging from flies to frogs to mice, it also can transmit early signals that separate an embryo into front and back or top and bottom.

During long-term memory formation, structural changes take place in the synapses the connections between neurons in the brain, says Kerry Ressler, MD, PhD, associate professor of psychiatry and behavioral sciences at Emory University School of Medicine. Ressler is a researcher at Emory University's Yerkes National Primate Research Center, where the research was conducted, and a Howard Hughes Medical Institute investigator.

"We thought beta-catenin could be a hub for the changes that take place in the synapses during memory formation," says Ressler. "But because beta-catenin is so important during development, we couldn't take the standard approach of just knocking it out genetically"......... Posted by: Daniel      Read more         Source

September 22, 2008, 10:24 PM CT

Statins increase risk of postoperative delirium

The use of statins is linked to a 28% increased risk of postoperative delirium in elderly patients, found University of Toronto professor Dr. Donald Redelmeier and his colleagues in a retrospective cohort analysis involving more than 280 000 patients.

Ontario's Institute for Clinical Evaluative Sciences (ICES) looked at elderly patients who underwent elective surgery in Ontario and who had received 2 or more prescriptions for statins in the year before surgery, including at least one prescription in the 90 days preceding surgery. A number of patients took multiple medications, underwent abdominal, musculoskeletal or urogenital surgery which had a mean duration of about 115 minutes.

Delirium, in addition to causing anxiety in patients and families, contributes to longer hospital stays, a prolonged need for intensive care, and can disrupt and delay care.

They observed that 1 in 14 elderly patients were taking statins before surgery and 1 in 90 experienced delirium. Longer surgeries and age over 70 years increased the risk of delirium.

"Our results suggest that this association was more than a coincidence, especially among patients who received higher doses of statins and had longer duration noncardiac surgeries," state Dr. Redelmeier and his colleagues. "The association between statins and risk of delirium was distinct and was not observed with other lipid-lowering medications, cardiovascular medications or common drugs that reflect underlying chronic diseases but have no major effects on the cardiovascular system"......... Posted by: JoAnn      Read more         Source

September 16, 2008, 10:25 PM CT

Emotions are key in the study of face recognition

Recognizing the faces of family and friends is commonly an effortless process. However, a minority of people have difficulties identifying the person they are meeting or remembering people they have met before. These problems can be quite dramatic, to the point where those affected fail to recognize the face of their spouse or child or even their own face. New research on face blindness demonstrates the importance of using naturalistic emotional faces and bodies for a better understanding of developmental face disorders.

The study, which is reported in the open-access journal PLoS ONE this week, by scientists in the Netherlands and at Massachusetts General Hospital, led by Beatrice de Gelder, shows that the presence of emotional information in the face increases neural activity in the area of the brain linked to face recognition (the fusiform face area, or FFA), a finding that could be used to design novel assessment and training programs. The study also provides evidence that body and face sensitive processes are less categorically segregated in people with face blindness and points to a possible cause of face blindness in cortical specialisation.

Recent research has shown that as much as 2% of the population suffers from face recognition difficulties. On analogy with developmental dyslexia, these cases are usually referred to as developmental prosopagnosia, referring to the possible origin of the adult face recognition deficit in anomalous development of the full face recognition skills......... Posted by: JoAnn      Read more         Source

September 15, 2008, 9:43 PM CT

Steady work and mental health - is there a connection?

Despite low overall unemployment, Canada's manufacturing industry has cut 88,000 jobs this year, with nearly all the losses occurring in Ontario. Also, part-time employment has grown by 3.5 per cent in 12 months, much faster than the 0.9 per cent growth in full time work. A new report from the World Health Organization (WHO) on the social determinants of health demonstrates that these kind of employment changes can affect more than your wallet. Research from the Centre for Addiction and Mental Health (CAMH)'s Dr. Carles Muntaner in the WHO report highlights the profound impact of employment conditions on health.

Dr. Muntaner and his research team observed that poor mental health outcomes are linked to precarious employment (e.g. temporary contracts or part-time work with low wages and no benefits). When compared with those with full-time work with benefits, workers who report employment insecurity experience significant adverse effects on their physical and mental health.

The research team have also observed that stress at work is linked to a 50 per cent excess risk of coronary heart disease, and there is consistent evidence that jobs with high demands, low control, and effort-reward imbalance are risk factors for mental and physical health problems (major depression, anxiety disorders, and substance use disorders). Canada and many other wealthy countries such as the U.K., the United States, Australia and New Zealand all face similar challenges, Dr. Muntaner notes, because there's a greater tolerance for inequities than in some other countries such as Sweden and Denmark......... Posted by: JoAnn      Read more         Source

September 14, 2008, 10:30 PM CT

Depressed dialysis patients more likely to be hospitalized

Dialysis patients diagnosed with depression are nearly twice as likely to be hospitalized or die within a year than those who are not depressed, a.

UT Southwestern Medical Center researcher has found.

In the study, available online and in the Sept. 15 issue of Kidney International, scientists monitored 98 dialysis patients for up to 14 months. More than a quarter of dialysis patients received a psychiatric diagnosis of some form of depression based on a Diagnostic and Statistical Manual of Mental Disorders 4th edition (DSM IV).

This is the first reported link between adverse clinical outcomes in dialysis patients and depression made through a formal psychiatric interview based on the DSM-IV standards. More than 80 percent of the depressed patients died or were hospitalized, compared with 43 percent of non-depressed patients. Cardiovascular events, which previously have been associated with depression, led to 20 percent of the hospitalizations.

"Twenty percent of patients who start dialysis will die by the end of the first year," said Dr. Susan Hedayati, assistant professor of internal medicine and the study's lead author. "What we don't know yet is, if their depression is treated, could it extend dialysis patients' survival and improve their quality of life"......... Posted by: JoAnn      Read more         Source

September 10, 2008, 10:03 PM CT

Abuse of painkillers can predispose to addiction

No child aspires to a lifetime of addiction. But their brains might. In new research to appear online in the journal Neuropsychopharmacology this week, Rockefeller University scientists reveal that adolescent brains exposed to the painkiller Oxycontin can sustain lifelong and permanent changes in their reward system changes that increase the drug's euphoric properties and make such adolescents more vulnerable to the drug's effects later in adulthood.

The research, led by Mary Jeanne Kreek, head of the Laboratory of the Biology of Addictive Diseases, is the first to directly compare levels of the chemical dopamine in adolescent and adult mice in response to increasing doses of the painkiller. Kreek, first author Yong Zhang, a research associate in the lab, and their colleagues observed that adolescent mice self-administered Oxycontin less frequently than adults, suggesting that adolescents were more sensitive to its rewarding effects. These adolescent mice, when re-exposed to a low dose of the drug as adults, also had significantly higher dopamine levels in the brain's reward center in comparison to adult mice newly exposed to the drug.

"Together, these results suggest that adolescents who abuse prescription pain killers may be tuning their brain to a lifelong battle with opiate addiction if they re-exposed themselves to the drug as adults," says Kreek. "The neurobiological changes seem to sensitize the brain to the drug's powerfully rewarding properties."........ Posted by: JoAnn      Read more         Source

September 8, 2008, 5:26 PM CT

Explaining winter blues

Why do a number of Canadians get the winter blues? In the first study of its kind in the living human brain, Dr. Jeffrey Meyer and his colleagues at the Centre for Addiction and Mental Health (CAMH) have discovered greater levels of serotonin transporter in the brain in winter than in summer. These findings have important implications for understanding seasonal mood change in healthy people, vulnerability to seasonal affective disorders and the relationship of light exposure to mood.

CAMH's scientific team discovered that the serotonin transporter levels were significantly higher in all investigated brain regions in individuals studied in fall/winter, in comparison to those studied in spring/summer in a study of healthy subjects. Serotonin transporters remove serotonin so this discovery argues that there is more serotonin removal in the fall/winter as in comparison to spring/summer. Also, the higher serotonin transporter binding values occurred at times when there is less sunlight. This is the first time researchers have found differences in serotonin transporter levels in the brain in fall/winter versus spring/summer.

Serotonin is involved in regulating physical functions such as eating and energy balance, and emotional functions like mood and energy levels. These phenomena vary across the seasons and the molecular background for why this happens was previously unknown. For this study, Dr. Jeffrey Meyer and his team used a world-leading positron emission tomography (PET) technology (originally created at CAMH by Dr. Alan Wilson) to detect these seasonal variations in serotonin transporter binding (the process that removes serotonin) in the living human brain and correlations between serotonin binding and duration of daily sunshine......... Posted by: JoAnn      Read more         Source

September 4, 2008, 3:59 PM CT

More off-premise alcohol outlets can lead to more injuries

Childhood injuries constitute a serious issue in the United States. In 2001, there were 12,249 deaths among children ages one to 14: injuries were the leading cause, accounting for 33.2 percent of all deaths for children ages one to four, and 39.4 percent of all deaths for children ages five to 14. A new study has observed that numerous off-premise alcohol outlets in neighborhoods can reduce overall guardianship of children's activities, leading to increased injuries.

Results would be reported in the recent issue of Alcoholism: Clinical & Experimental Research and are currently available at Early View.

"Neighborhood areas with high levels of social disorganization can make the children who live there more vulnerable to injury in many ways," explained Bridget Freisthler, assistant professor in the department of social welfare at the University of California, Los Angeles (UCLA) and affiliated research scientist at the Prevention Research Center, Pacific Institute for Research and Evaluation (PRC/PIRE). This research was a joint project between UCLA and PRC/PIRE.

"Impoverished and disorganized neighborhoods may present more physically dangerous environments," said Freisthler. "Limited social capital restricts their ability to respond to social problems that might endanger children's health and well being. Reduced levels of social control may facilitate risky behaviors, such as playing in dangerous streets or vacant buildings. And, areas that have fewer adults available to monitor and supervise children's activities may further exacerbate problem behaviors"......... Posted by: Janet      Read more         Source

September 3, 2008, 7:00 PM CT

College freshmen: pain killers and stimulants less risky than cocaine

First year college students think that occasional nonmedical use of prescription pain killers and stimulants is less risky than cocaine, but more risky than marijuana or consuming five or more alcoholic beverages every weekend, as per a new study reported in the recent issue of Prevention Science, the peer-evaluated journal of the Society for Prevention Research.

This is the first study to describe college students' perceptions about the potential harmfulness of nonmedical use of prescription pain killers and stimulants. Prior studies with high school students show that beliefs about harmfulness of illicit drugs are correlation to drug use. Nonmedical use of pain killers and stimulants can be addictive and can cause serious problems requiring emergency room therapy.

The study by Amelia Arria, Ph.D., of the Center for Substance Abuse Research at the University of Maryland, also observed that college students who can be described as "sensation-seekers" are more likely to use prescription drugs nonmedically; irrespective of how harmful they may perceive the drugs to be. Arria said "sensation-seekers are students who like novel experiences, who want to try something new and a little dangerous, like jumping off the highest diving board or placing themselves in high-risk situations. They are much more likely to use pain killers nonmedically even if they perceive the drugs to be quite harmful"......... Posted by: JoAnn      Read more         Source

August 31, 2008, 9:07 PM CT

Chewing gum may help reduce stress

WHAT: "An investigation into the effects of gum chewing on mood and cortisol levels during psychological stress," to be presented at the 2008 10th International Congress of Behavioral Medicine, observed that chewing gum helped relieve anxiety, improve alertness and reduce stress among individuals in a laboratory setting.* The study examined whether chewing gum is capable of reducing induced anxiety and/or acute psychological stress while participants performed a battery of 'multi-tasking' activities. The use of chewing gum was linked to higher alertness, reduced anxiety and stress, and improvement in overall performance on multi-tasking activities.

WHO: Andrew Scholey, Ph.D., professor of Behavioral and Brain Sciences, Swinburne University in Melbourne, Australia led the research study and can discuss the effect of chewing gum on stress relief and focus and concentration.

Gilbert Leveille, Ph.D., executive director, Wrigley Science Institute, will also be available to discuss research on the benefits of chewing gum correlation to stress relief and alertness and concentration in addition to other areas including weight management and oral health.

WHEN: Study to be presented orally on Saturday, August 30 at Rissho University in Tokyo, Japan at the 10th International Congress of Behavioral Medicine......... Posted by: JoAnn      Read more         Source

August 31, 2008, 8:34 PM CT

The association with stress and depression

The brain is the key organ in the response to stress. It reacts in a complex, orchestrated manner that is correlation to the activation and inhibition of neural structures involved in sensory, motor, autonomic, cognitive and emotional processes. It is the brain which finally determines what in the world is threatening and might be stressful for us, and which regulates the stress responses that can be either adaptive or maladaptive. Chronic stress can affect the brain and lead into depression: Environmental stressors (e.g. job and family situation, neighborhood) and particularly stressful life events such as trauma or abuse are amongst the most potent factors to induce depression. Since the development of novel approaches to antidepressant therapy is based upon an improved neurobiological understanding of this condition, new information about the cellular changes that take place in the brain is required.

Depression: a growing public health burden

Depression is a chronic, recurring, multifactorial, and life-threatening disorder, which represents a collection of psychological, neuroendocrine, physiological and behavioural symptoms. Chronicity and frequency of these symptoms constitute the clinical condition. Depressive disorders affect up to 20% of people at some time in their life. In primary care, an estimated 20��% of patients suffer from depression, but often are not diagnosed correctly (Wittchen, 2000)......... Posted by: JoAnn      Read more         Source

August 27, 2008, 9:06 PM CT

Army personnel show increased risk for migraine

Two new studies show that migraine headaches are very common among U.S. military personnel, yet the condition is frequently underdiagnosed. The studies, appearing in Headache, the peer-evaluated journal of the American Headache Society, examine the incidence among soldiers within 10 days of returning from a 1-year combat tour in Iraq , as well as U.S. Army officer trainees.

The U.S. active-duty military population is composed chiefly of young adults, which is the age group at highest risk for migraine. However, the reported rates are higher than those of similar age and gender in the general U.S. population.

The findings show that 19 percent of soldiers returning from Iraq screened positive for migraine and an additional 17 percent screened positive for possible migraine. Soldiers with a positive migraine screen suffered a mean average of 3.1 headache days per month, headache durations of 5.2 hours and 2.4 impaired duty days per month due to headache. Soldiers with migraine contacted 3 months after returning from Iraq had a mean of 5.3 headache days per month.

18 percent of U.S. Army officer trainees experienced migraine headaches over a 1-year period (13.9 percent for males, 31.4 percent for females) and, of those, 50 percent experienced migraines during a 5-week period of intensive military training. Migraine headaches were found to significantly impede training in 4 percent of all cadets during this time. 76 percent of cadets who screened positive for migraine had never been diagnosed......... Posted by: Daniel      Read more         Source

August 21, 2008, 8:30 PM CT

How addiction develops

Permanent drug seeking and relapse after renewed drug administration are typical behavioral patterns of addiction. Molecular changes at the connection points in the brain's reward center are directly responsible for this. This finding was published by a research team from the Institute of Mental Health (ZI) in Mannheim, the German Cancer Research Center (DKFZ) in Heidelberg and the University of Geneva, Switzerland, in the latest issue of Neuron The results provide scientists with new approaches in the medical therapy of drug addiction.

Addiction leaves detectable traces in the brain: In particular regions of the central nervous system, which produce the messenger substance dopamine, the drug cocaine causes molecular restructuring processes at the synapses, the points of correlation between two neurons. As a reaction to the drug, protein subunits are exchanged in specific receptor complexes. As a result, the modified synapse becomes able to transmit nervous signals with enhanced strength a phenomenon that has been termed 'drug-induced synaptic plasticity'. Scientists have suspected for a number of years that drug-induced synaptic plasticity plays a crucial role in addiction development. However, this hypothesis has still not been proven experimentally.

Using genetic engineering, scientists headed by Professor Dr. Gnther Schtz at the German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ) have now been able to selectively switch off those protein components in dopamine-producing neurons that are integrated into the receptor complexes under the influence of cocaine. Jointly with the team of Professor Dr. Rainer Spanagel at the Central Institute of Mental Health (Zentralinstitut fr Seelische Gesundheit, ZI) in Mannheim and the research group of Professor Dr. Christian Lscher at Geneva University, the Heidelberg scientists studied the changes in physiology and behavior of the genetically modified animals......... Posted by: JoAnn      Read more         Source

August 20, 2008, 1:27 AM CT

Alcohol dependence linked to delayed childbearing

Alcohol use during the teen years can not only lead to subsequent alcohol problems, it can also lead to risky sexual behavior and a greater risk of early childbearing. An examination of the relationship between a lifetime history of alcohol dependence (AD) and timing of first childbirth across reproductive development has observed that AD in women is linked to delayed reproduction.

Results would be reported in the recent issue of Alcoholism: Clinical & Experimental Research and are currently available at Early View.

"Reproductive dysfunctions include a range of menstrual disorders, sexual dysfunctions, and pregnancy complications that include spontaneous abortion or miscarriage," explained Mary Waldron, assistant professor of psychiatry at Washington University School of Medicine and corresponding author for the study. "Teenagers who drink tend to have disruptions in their menstrual cycle as well as unplanned pregnancies."

These complications may become more pronounced with time, added Sharon C. Wilsnack, Chester Fritz Distinguished Professor in the department of clinical neuroscience at the University of North Dakota School of Medicine & Health Sciences. "Higher rates of reproductive dysfunction in adult women may reflect the cumulative effects of longer exposure to alcohol for older women than for female adolescents," she said......... Posted by: Janet      Read more         Source

August 18, 2008, 8:58 PM CT

For Earlier Detection Of Autism

Recently, Harvard scientists reported that children with autism have a wide range of genetic defects, making it nearly impossible to develop a simple genetic test to identify the disorder. Now, University of Missouri scientists are studying 3-D imaging to reveal correlations in the facial features and brain structures of children with autism spectrum disorder (ASD), which will enable them to develop a formula for earlier detection of the disorder. The scientists anticipate their work also will reveal genetic clues that can direct additional research. Autism is a brain disorder characterized by a complex of social, communication and behavioral difficulties.

"When you compare the faces and head shapes of children with specific types of autism to other children, it is obvious there are variations. Currently, autism diagnosis is purely behavior based and doctors use tape measurements to check for facial and brain dissimilarities. We are in the process of developing a quantitative method that will accurately measure these differences and allow for earlier, more precise detection of specific types of the disorder," said Ye Duan, assistant computer science professor in the MU College of Engineering. "Once we have created a formula, we can pre-screen children by performing a quick, non-invasive scan of each child's face and brain to check for abnormalities. Early detection is crucial in treating children and preparing families"......... Posted by: JoAnn      Read more         Source

August 13, 2008, 0:38 AM CT

'Erasing' drug-associated memories

'Erasing' drug-associated memories may prevent recovering drug abusers from relapsing, scientists at the University of Cambridge have discovered.

The team, led by Professor Barry Everitt, was able to reduce drug-seeking behaviours in rats by blocking a brain chemical receptor important to learning and memory during the recall of drug-associated memories. Their research, which was funded by the Medical Research Council, was published in the 13 recent issue of The Journal of Neuroscience.

The Cambridge researchers observed that by disrupting or erasing memories linked to drug use during recall, they could prevent the memories from triggering relapses and drug taking.

Memories exist in different states depending on whether they are being recalled or not. When memories are recalled, they become 'unstable' or malleable and can be altered or erased during the process called reconsolidation. Because relapse by drug abusers is often prompted when they recall drug-associated memories, the researchers observed that by blocking these memories they could prevent relapse.

In order to undertake the experiments, the scientists trained rats to associate the switching on of a light with cocaine. The scientists then exposed the rats to the light, thereby 'reactivating' the memory, without the cocaine. In an effort to receive more cocaine, the rats would perform tasks that the researchers had created which would turn on the light......... Posted by: JoAnn      Read more         Source

July 29, 2008, 11:56 PM CT

Right place and right time can trigger drinking

Strong cravings for alcohol can be sparked by the mere sight, smell and taste of a person's favorite drink. Responses to such cues that are linked to the positive effects of drinking are a lead cause of relapse in abstinent alcoholics. Using a behavioral animal model, scientists of a new study, scheduled for publication in the August 1st issue of Biological Psychiatry, have observed that the physical surroundings where alcohol cues are experienced can greatly influence the ability of those cues to trigger relapse.

Specifically, Chaudhri and his colleagues taught rats to learn that a brief tone signaled when a small amount of alcohol would be available in a fluid receptacle for them to drink. This learning occurred in a distinctive environment consisting of a particular appearance, smell, and lighting. They were then put into a second, unique context with a different appearance, smell, and lighting, and were repeatedly exposed to the tone but never given alcohol. After several sessions in this new context, the rats gradually learned that the tone no longer predicted alcohol and consequently stopped checking the fluid receptacle. However, upon re-exposure to the original context where alcohol was available, presentation of the tone once again caused the rats to immediately check for it. "This finding demonstrates the power of environments to trigger relapse to alcohol-seeking in response to alcohol-predictive cues," said lead author Nadia Chaudhri, Ph. D., with the Ernest Gallo Clinic and Research Center at UCSF. "This effect is highly detrimental to humans who are trying to abstain from drinking." ......... Posted by: JoAnn      Read more         Source