1. Epigenetic study untangles addiction and relapse in the brain

    October 6, 2017 by Ashley

    From the Medical University of South Carolina press release:

    Why do some drug users continue to seek out drugs despite the prospect of losing family, friends, health or livelihood?

    There are notable features — cues — of the early drug-using environment that often develop into persistent and powerful triggers for relapse. Epigenetic factors — enzymes in the brain that alter the packaging and accessibility of genes without changing the genes themselves — influence this process, according to research at the Medical University of South Carolina (MUSC) appearing online on September 27, 2017 in Neuron.

    A major challenge in addiction science is to understand how transient experiences lead to long-lasting risk for relapse in users who try to quit, according to MUSC professor Christopher W. Cowan, Ph.D., William E. Murray SmartState® Endowed Chair in Neuroscience, and senior researcher on the project. “Our goal was to discover the brain mechanisms responsible for the rewarding effects of the drug and the motivation to seek it even after long periods of abstinence,” says Cowan.

    The brains of drug users who have progressed to addiction differ markedly from those of early or casual users. Long-lasting associations form between the early use of a drug and different aspects of the early drug-using environment, such as the location in which a drug was first taken or the emotions a user was experiencing at the time. This can cause addicted users who have quit to experience cravings when in a similar setting. Understanding these connections could lead to better treatments for addiction.

    Cowan’s challenge was to determine which genes were activated in the early drug-using environment. Cowan and his fellow researchers had previously found that the epigenetic enzyme histone deacetylase 5 (HDAC5) slows the rodent brain from forming associations between cocaine and simple cues in the environment, such as light and sound. HDAC5 is found in high amounts in neurons in the nucleus accumbens, part of the reward center of the brain that reacts strongly to cocaine, opioids and alcohol — both in rodents and humans. When HDACs are in the nucleus of neurons, they change the way genomic DNA is packaged in the cell nucleus and often block the ability of certain genes to be turned on.

    In the new study, rodents were trained to press a lever to receive a dose of cocaine. Each time they received a dose, a lamp went on above the lever and a brief sound was generated. These served as simple environmental cues for drug use. Next, some rodents were given a form of HDAC5 that traveled straight to the nuclei of neurons. Those rodents still pressed the lever just as many times to receive drug, meaning that HDAC5, on its own, was likely not blocking genes that promoted early drug-seeking behavior.

    Yet the next experiment proved that HDAC5 reduced drug-seeking behavior during abstinence. To simulate withdrawal and abstinence, rodents were given rest without cocaine for one week, followed by a period during which they had access to the lever again. To simulate relapse, the rodents were shown the environmental cues again, this time without having pressed the lever. The presentation of the cues triggered robust lever pressing, indicating drug seeking, in control animals, proving that the associations between drug and environment persisted in their brains. In contrast, animals who had the nuclear form of HDAC5 did not press the lever nearly as often, even after the experimenters gave the animals a small priming dose of cocaine, which often produces strong drug-seeking behaviors.

    HDAC5, the gene suppressor, did not prevent addiction-like behaviors from forming, but it did prevent later drug seeking and relapse during abstinence — at least in rodents.

    The researchers next used a cutting-edge technique that encourages epigenetic enzymes to bind to DNA, allowing them to identify all the genes inhibited by HDAC5. The gene for NPAS4 was a top hit, and significant for an important reason: it is an early-onset gene, meaning that its effects could be exerted on the brain rapidly unless HDAC5 was there to inhibit it — just the molecular event Cowan and his team were seeking.

    In similar experiments, animals with less NPAS4 in the nucleus accumbens took more time to form those early connections between environmental cues and cocaine, but they still sought the drug just as often during later simulated relapse. Apparently, NPAS4 accounts for some addiction-related learning and memory processes in the brain, but not all of them, meaning that HDAC5 must be regulating additional genes that reduce relapse events. Cowan thinks uncovering additional downstream genes could help researchers untangle the details of how the brain transitions from early drug use to addiction, and how new treatments might be developed to reduce relapse in individuals suffering from substance use disorders.

    Animals in the research setting may not mimic the full complexity of human addiction. However, abstinent patients report cravings when given reminders of their drug-associated environment or cues, and animals and humans share similar enzyme pathways and brain structures. Perhaps most exciting for addiction research is that these processes may be similar in the transition to cocaine, alcohol and opioid addictions. “We might have tapped into a mechanism with relevance to multiple substance use disorders,” says Cowan.


  2. Study suggests that child abuse may affect brain wiring

    by Ashley

    From the McGill University press release:

    For the first time, researchers have been able to see changes in the neural structures in specific areas of the brains of people who suffered severe abuse as children. Difficulties associated with severe childhood abuse include increased risks of psychiatric disorders such as depression, as well as high levels of impulsivity, aggressivity, anxiety, more frequent substance abuse, and suicide.

    Crucial insulation for nerve fibres builds up during first two decades of life

    For the optimal function and organization of the brain, electrical signals used by neurons may need to travel over long distances to communicate with cells in other regions. The longer axons of this kind are generally covered by a fatty coating called myelin. Myelin sheaths protect the axons and help them to conduct electrical signals more efficiently. Myelin builds up progressively (in a process known as myelination) mainly during childhood, and then continue to mature until early adulthood.

    Earlier studies had shown significant abnormalities in the white matter in the brains of people who had experienced child abuse. (White matter is mostly made up of billions of myelinated nerve fibres stacked together.) But, because these observations were made by looking at the brains of living people using MRI, it was impossible to gain a clear picture of the white matter cells and molecules that were affected.

    To gain a clearer picture of the microscopic changes which occur in the brains of adults who have experienced child abuse, and thanks to the availability of brain samples from the Douglas-Bell Canada Brain Bank (where, as well as the brain matter itself there is a lot of information about the lives of their donors) the researchers were able to compare post-mortem brain samples from three different groups of adults: people who had committed suicide who suffered from depression and had a history of severe childhood abuse (27 individuals); people with depression who had committed suicide but who had no history of being abused as children (25 individuals); and brain tissue from a third group of people who had neither psychiatric illnesses nor a history of child abuse (26 people).

    Impaired neural connectivity may affect the regulation of emotions

    The researchers discovered that the thickness of the myelin coating of a significant proportion of the nerve fibres was reduced ONLY in the brains of those who had suffered from child abuse. They also found underlying molecular alterations that selectively affect the cells that are responsible for myelin generation and maintenance. Finally, they found increases in the diameters of some of the largest axons among only this group and they speculate that together, these changes may alter functional coupling between the cingulate cortex and subcortical structures such as the amygdala and nucleus accumbens (areas of the brain linked respectively to emotional regulation and to reward and satisfaction) and contribute to altered emotional processing in people who have been abused during childhood.

    The researchers conclude that adversity in early life may lastingly disrupt a range of neural functions in the anterior cingulate cortex. And while they don’t yet know where in the brain and when during development, and how, at a molecular level these effects are sufficient to have an impact on the regulation of emotions and attachment, they are now planning to explore this in further research.


  3. Study suggests binge drinking in college may lower chances of landing a job after college

    October 1, 2017 by Ashley

    From the American Friends of Tel Aviv University press release:

    Heavy drinking six times a month reduces the probability that a new college graduate will land a job by 10 percent, according to Tel Aviv University and Cornell University research published in the Journal of Applied Psychology.

    Previous studies were unable to determine the precise effect of alcohol consumption on first-time employment. But according to the new study, each individual episode of student binge-drinking during a month-long period lowers the odds of attaining full-time employment upon graduation by 1.4 percent.

    “The manner in which students drink appears to be more influential than how much they drink when it comes to predicting the likelihood of getting a job upon graduation,” says Prof. Peter Bamberger of TAU’s Coller School of Business Management and Cornell University, who co-authored the study with Prof. Samuel Bacharach of Cornell University; Prof. Mary Larimer and Prof. Irene Geisner, both of the University of Washington; Jacklyn Koopmann of Auburn University; Prof. Inbal Nahum-Shani of the University of Michigan; and Prof. Mo Wang of the University of Florida.

    “Binge-drinking” is defined as ingesting four or more alcoholic drinks within two hours by a woman and five or more alcoholic drinks within two hours by a man, according to the National Institute on Alcohol Abuse and Alcoholism.

    How often, not how much

    The research found that a non-binge pattern of drinking does not adversely impact job search results unless and until their drinking reaches binge levels.

    Data for the study was provided by 827 individuals who graduated in 2014, 2015, and 2016 from Cornell, the University of Washington, the University of Florida, and the University of Michigan.

    “A student who binge-drinks four times a month has a 6 percent lower probability of finding a job than a student who does not engage in similar drinking habits. Those students who drank heavily six times a month increased their unemployment probability to 10 percent,” says Prof. Bamberger.

    Funded by a $2.2 million grant from the National Institute on Alcoholism and Alcohol Abuse, the research is the first installment of a longitudinal study on how alcohol misuse affects the college-to-work transition. More than 16,000 individuals have been contacted as part of the five-year study.

    “This paper is consistent with the recent emphasis on the impact of drinking behavior on career transition from Cornell’s Smithers Institute,” said Prof. Bacharach. “It is in concert with the previous work we’ve done on retirement, and on-boarding [the entry and socialization of newcomers into an organization]. Most importantly, it is also consistent with the Smithers Institute’s continued programmatic interest in substance abuse not only in the workplace, but in the college community as well.”


  4. Study looks at neurological aspects of quitting cocaine addiction

    September 25, 2017 by Ashley

    From the Mount Sinai Hospital / Mount Sinai School of Medicine press release:

    Cocaine-addicted individuals say they find the drug much less enjoyable after years of use, but they have great difficulty quitting. A new brain imaging study led by researchers at the Icahn School of Medicine at Mount Sinai reveals why this might be so, as well as why a common psychological therapy may not work in addicted cocaine users.

    Their study, published September 5 in Addiction Biology, finds that chronic users have a “global impairment” in the ventromedial prefrontal cortex (VMPFC), an area of the brain that is linked to impulse and self-control, and is responsible for the kind of learning that assigns value to objects and behaviors.

    The Mount Sinai study investigated a specific type of learning called extinction — the process by which a new, affectively neutral, association replaces an old, affectively arousing association — to identify the neurobiological mechanism that underlies the persistence of drug seeking in addiction despite negative consequences and a reduction in the drug’s rewarding affects.

    To investigate these questions, the research team collected functional magnetic resonance imaging (fMRI) data on a three-phase classical conditioning paradigm in individuals with a history of chronic cocaine use and healthy control individuals without the drug habit. They found that in drug-addicted individuals, there was a VMPFC-mediated impairment in forming and maintaining new associations for stimuli that were previously, although no longer, predictive of both drug and non-drug related outcomes.

    “Our study data suggests that it will be hard for longtime cocaine users to unlearn what once was a positive experience if this ‘unlearning’ or new learning relies on this brain region to be effective,” says the study’s lead investigator, Anna Konova, PhD, who worked on the study while at the Icahn School of Medicine, but who is now a postdoctoral fellow at the Center for Neural Science at New York University.

    Extinction forms the basis for exposure therapy, which is often used to treat anxiety disorders like phobias.

    “There is a strong impetus for extinction-based therapy in addiction, but our findings highlight potential limitations of these existing therapies in their reliance on the VMPFC to achieve therapeutic benefits,” says the study’s senior investigator, Rita Z. Goldstein, PhD, who directs Mount Sinai’s Neuropsychoimaging of Addiction and Related Conditions research group.

    Dr. Goldstein is an international expert in the use of functional neuroimaging methods to examine the neurobiological basis of impaired cognitive and emotional functioning in human drug addiction and other disorders of self-control. Dr. Konova was a graduate student in Dr. Goldstein’s lab.

    A well-known example of the kind of learning that Dr. Konova and the research team studied in this study is the famous “Pavlov’s dog” experiment in which dogs learned to associate a food treat with the sound of a bell. Dogs soon started salivating when the bell rang. But if the bell rang enough times without being followed by the treat the salivation response of the dogs was reduced or extinguished.

    “The idea behind extinction learning as a therapeutic intervention is that a user can learn to substitute a relaxing thought — such as taking a nature stroll — for the thought of procuring cocaine when walking by their neighborhood park where they might have previously purchased or consumed the drug. By relying on these new associations, an addicted individual may be able to control their habit,” says Dr. Konova.

    Fear-based extinction learning is now widely used to treat anxiety, such as in phobias and post-traumatic stress disorder (PTSD). In this technique, a person is exposed to the thing that makes them afraid until the fear response to that thing (which is no longer associated with any real harm) is reduced and eventually extinguished, perhaps by forming a new, neutral or positive, association with their originally feared object or situation.

    While previous experiments have suggested VMPFC impairment in addicted individuals who have long used stimulants such as cocaine — a consistent finding is that the gray matter (a marker of neuronal morphological integrity) is altered in that brain area in these individuals — this is the first experiment to examine if these changes have implications for extinction learning in drug users and non-users using functional magnetic resonance imaging (fMRI) brain scans.

    The study participants — 18 chronic cocaine users and 15 control individuals from the same community — completed three rounds of learning over two days. The cocaine-using individuals had an average lifetime history of 17 years of cocaine use and currently used cocaine about twice a week. None were seeking treatment to stop.

    On the first day, while in the fMRI scanner, participants were shown, say, a colored square (a neutral cue) followed by a picture of a pleasant stimulus (such as a puppy), a different colored square this time followed by a drug-related picture (such as a crack pipe), and a third one followed by a picture of a household item. Like Pavlov’s dogs, the control individuals learned to anticipate the corresponding picture once they saw the specific square (anticipating the puppy, the drug item, or the household item). Their VMPFC also responded accordingly. They had learned the first association.

    Next, the groups were shown just the cues (squares) repeatedly and depending on the picture that had been linked to them before, their brain responses again responded accordingly: VMPFC responses now were not as high to the cues that predicted the picture of the puppy (a pleasant stimulus) and not as low as to the cues that predicted the crack pipe (an unpleasant stimulus). This was the first extinction phase, when extinction learning should occur. That is, new learning was taking place that the affectively charged pictures no longer followed the cues.

    Participants stayed overnight, and the next morning, they were shown the cues again. The extinction response was even more pronounced this time due to retention of some of the extinction association from the previous day.

    However, VMPFC signals in the cocaine-using group did not resemble that of the control group. Their data revealed that extinction learning did not engage the VMPFC to the same degree, which could result in failures in extinction learning, Dr. Konova says.

    “It may be possible to train other areas of the brain, such as the striatum, which we found did have normal responses in the drug users, to update the strong and well-established drug associations,” she says. “Or there could be ways to increase VMPFC function through cognitive retraining or pharmacologically. But our findings suggest that neither extinction learning for positive outcomes — anticipating seeing a cute puppy when this is no longer likely — or drug-related outcomes — anticipating seeing a crack pipe when this too is no longer likely — using that critical brain area will help longtime cocaine users quit.”

    “This really highlights the importance of neuroscience-informed treatment development for addiction, as this study and others like it can help speak to why some current approaches might fail or discover new, more effective ways to intervene,” says Dr. Goldstein.


  5. Study suggests sportspeople can face retirement identity crisis

    September 22, 2017 by Ashley

    From the University of Portsmouth press release:

    New research shows how top-level sportspeople can struggle to adjust to life after retirement, with their identities continuing to be defined by their former careers.

    The research, published in the journal Qualitative Research in Sport, Exercise and Health, illustrates how some athletes struggle to adjust socially and psychologically following retirement. Previous studies have shown that in the most extreme cases it can lead to depression, eating disorders and substance abuse.

    The study was led by Dr Francesca Cavallerio of Anglia Ruskin University, who worked alongside Dr Chris Wagstaff of the University of Portsmouth and Dr Ross Wadey of St Mary’s University.

    Dr Wagstaff said: “Adapting to retirement is difficult for many people in society and this is particularly the case in elite sport. Such environments are characterised by very clear social and cultural expectations. In order to be successful, athletes typically conform to and associate success with these cultural norms.

    “This study showed that, unfortunately, when athletes retire many struggle to identify with anything other than their sport, which for many, has been the principal focus of their life for many years. Therefore, sport organisations must do more to support the non-sport lives of their athletes.”

    Dr Cavallerio, a Lecturer in Sport and Exercise Sciences at Anglia Ruskin University, interviewed female gymnasts who had retired from elite-level competition and found that their stories followed one of three narratives or storylines: Entangled, Going forward and Making sense.

    For instance, some former gymnasts who were identified as entangled had their identities completely defined by their former athletic self and the values instilled in them when they competed. They struggled to adapt to life after gymnastics and suffered from low confidence, low self-esteem, and a lack of drive towards new goals and experiences.

    The going forward former athletes were able to develop different identities to that of a gymnast at the same time as they were competing at a high level. Once their gymnastics careers were over, they were able to make the most of what they had learnt in sport to help their future development.

    Those in the making sense group fell somewhere in between, not confident enough to be going forward but struggling not to remain entangled in their former life. Future experiences were likely to decide whether they would more closely follow the going forward or entangled narratives.

    Dr Cavallerio said: “Sport continues to embrace the early identification and development of talented athletes. In many sports, the age at which people begin training at a professional level is getting younger.

    “Our study shows that how athletes are treated and influenced at a young age can have an effect on how they deal with retirement.

    “The issues we observed should be of interest to clubs and governing bodies across a range of sports. On a practical level they should be encouraging young athletes to develop a non-sporting identity at the same time as a sporting identity, and have a range of interests and friendships outside of their sport.”


  6. Study links sleep disturbances to higher incidence of substance use among college athletes

    June 16, 2017 by Ashley

    From the American Academy of Sleep Medicine press release:

    Preliminary results of a new study show that sleep disturbance is strongly related to the use of alcohol, tobacco, and illicit drugs among student athletes in college.

    Results show that student athletes with sleep difficulties were 151 percent more likely to use cigarettes, 36 percent more likely to drink alcohol, and 66 percent more likely to smoke marijuana. Sleep difficulties also predict an increased use of controlled, illegal, and banned substances. For example, student athletes with sleep difficulties were 317 percent more likely to use methamphetamine, 349 percent more likely to use cocaine, and 175 percent more likely to use steroids.

    “The most surprising thing was the consistency with which sleep difficulties among student athletes predict increased use of many substances, including substances that are illegal and banned,” said senior author Michael Grander, PhD, director of the Sleep and Health Research Program at the University of Arizona in Tucson. “Across the board, students with sleep difficulties were more likely to smoke, drink, and use illegal substances.”

    The study involved an analysis of survey data completed from 2011 to 2014 by 8,683 student athletes at U.S. colleges and universities as part of the National College Health Assessment conducted by the American College Health Association. Participants were asked whether, in the past 12 months, “sleep difficulties” had “been traumatic or very difficult for you to handle.” Students also were asked whether they had used a list of specific substances in the past 30 days.

    Regression analyses examined whether use of any of these substances was associated with sleep difficulties, adjusted for age, sex, and survey year. Also, discrepancy between student use and perceived typical use and sleep was examined.

    “Sleep difficulties are quite common among students and especially student athletes,” said lead author Chloe Warlick, research assistant in the Sleep and Health Research Program. “Substance use is also a major public health problem. These results not only underscore the important link between sleep difficulties and substance use, but they show that this relationship is quite strong, even among student athletes.”

    Grandner added that the findings have important implications for both student health and athletic performance.

    “Knowing this association between sleeping difficulty and substance abuse could be beneficial for coaches, physical therapists, and physicians,” he said. “These findings could provide important insight when treating sleep disturbances or attempting to improve athletic performance.”

    The authors concluded that sleep-focused interventions should be evaluated to determine whether they decrease use of psychoactive substances.


  7. Study suggests growing up in affluent communities may up risk for addictions

    June 13, 2017 by Ashley

    From the Arizona State University press release:

    They have what most would want — affluent upwardly mobile parents, living in comfortable homes in the suburbs, going to an elite high school and being groomed for the nation’s best colleges. And they appear to thrive in this setting — popular among their peers, performing exceedingly well in school, highly regarded by peers and teachers, and accomplished at a various extracurricular activities.

    But these “privileged” American high schoolers can be at high risk for problematic substance abuse across early adulthood, according to new research from Arizona State University.

    “We found alarmingly high rates of substance abuse among young adults who we initially studied as teenagers,” said Suniya Luthar, a Foundation professor of psychology at Arizona State University and a professor emerita at Columbia University’s Teachers College, who led the research. “Results showed that among both men and women and across annual assessments, these young adults had substantial elevations, relative to national norms, in frequency of several indicators — drinking to intoxication and of using marijuana, stimulants such as Adderall, cocaine, and club drugs such as ecstasy.”

    The paper, “Adolescents from upper middle class communities: Substance misuse and addiction across early adulthood,” appears in the current issue of Development and Psychopathology. It is co-authored by Phillip Small, an ASU graduate student in clinical psychology, and Lucia Ciciolla an assistant professor at Oklahoma State University.

    In the article, the authors describe a study of two groups of students in affluent communities in the Northeast U.S. as part of the New England Study of Suburban Youth (NESSY). The researchers assessed these youngsters as high school seniors and then annually across four college years (NESSY-Y, for the younger cohort), and across ages 23 to 27 (NESSY-O, for the older cohort).

    “We found rates of addiction to drugs or alcohol among 19 to 24 percent of women in the older cohort by the age of 26, and 23 to 40 percent among men. These rates were 3 and 2 times as high respectively, as compared to national norms,” Luthar said. “Among the younger cohort by the age of 22 years, rates of addiction were between 11 and 16 percent among women (close to national norms) but 19 to 27 percent among men, or about twice as high as national norms.”

    Luthar said a look into the lives of these adolescents provide some clues to the cause of these high rates of addictions.

    When the NESSY groups were first assessed, they all attended the best schools in the region — suburban schools with very high-standardized test scores, rich extra curricular offerings and high proportions of their graduates heading off to very selective universities. In general, kids at such schools experience enormous pressures to achieve, and many come to live by the dual credos of “I can, therefore I must” and “we work hard and we play hard” with the playing involving parties with drugs and alcohol.

    Also implicated is affluence in the school community.

    “Not all of these students were from wealthy families but most were; as parents typically had advanced educational degrees and median incomes much higher than national norms,” Luthar said. “And without question, most of the parents wanted their kids to head off to the best universities, as did the kids themselves.”

    With affluence comes ease in acquiring drugs, she added. “Many kids in these communities have plenty of disposable income with which they can get high-quality fake ID’s, as well as alcohol and both prescription and recreational drugs.”

    Other factors that exacerbate the risks, Luthar said, include widespread peer approval for substance use, and the fact that parents can be lulled into a false sense of security, believing that as their kids continue to perform well in school there could not be any serious underlying issues. As a result, they can become somewhat laissez-faire about detected alcohol or marijuana use.

    So what can be done to reverse this trend?

    “This is a problem that derives from multiple levels of influence, so we’re going to need interventions at multiple levels to tackle it,” Luthar said.

    “At the level of the kids themselves and their parents, it will be important to disseminate research findings — based on rigorous scientific data — that messing with drugs and alcohol really should not be trivialized as just something all kids do,” Luthar said. “The earlier children start to use and the more frequently they do, the more likely it is that they will develop addictions down the line.”

    Luthar pointed to strategies like sex education programs conveying the “bottom line” of risks involved, such as “it only takes once” to contract a sexually transmitted disease.

    “For high-achieving and ambitious youngsters, it could actually be persuasive to share scientific data showing that in their own communities the statistical odds of developing serious problems of addiction are two to three times higher than norms. And that it truly just takes one event of being arrested with cocaine, or hurting someone in a drunken car accident, to derail the high profile positions of leadership and influence toward which they are working so hard for the future.”

    On a second level is reducing the enormous pressure these kids are under trying to get into only the most selective universities.

    “As long as university admissions processes continue to be as they are — increasingly smaller number of admits per applications and requiring impossible resumes — these young people will continue to be frenetic in pursuing those coveted spots — and many will continue to self-medicate as a result,” explained Luthar. “An alternative approach, suggested by my colleague Barry Schwartz, could be to have these highly selective universities institute a lottery system for final admittance, given all other qualifications and resumes being equal.

    A second important measure would be showing the kids there are role models of adults who did not go to an elite university, but who picked a college because it felt right for them and who were highly successful in life.

    “It shows that there is, in fact, life, wisdom, financial solvency, creativity, and yes, happiness, beyond the walls of the Ivy Leagues,” Luthar said.

    A third factor is for leaders in science, public health and social policy to take seriously the fact that youth at high-achieving schools could be a population that is at inordinately high risk for addiction. Decades ago, developmental researchers established that children growing up in chronic poverty were at high risk for maladjustment, and this led, laudably, to a plethora of studies trying to figure out how best to minimize risks, and foster resilience among these youth by addressing different aspects of their environments.

    “We now need the same dedicated research on kids who grow up in pressure- cooker, high achieving schools,” Luthar said. “Paradoxical though it may seem, these ostensibly privileged youth, many of who start experimenting early and often with drinking and drugs, could well be among the groups at highest risk for alcoholism and addiction in adulthood.”


  8. Brain area involved in addiction activated earlier by cocaine consumption than thought

    June 6, 2017 by Ashley

    From the McGill University press release:

    Even among non-dependent cocaine users, cues associated with consumption of the drug lead to dopamine release in an area of the brain thought to promote compulsive use, according to researchers at McGill University.

    The findings, published in Scientific Reports, suggest that people who consider themselves recreational users could be further along the road to addiction than they might have realized.

    “The study provides evidence that some of the characteristic brain signals in people who have developed addictions are also present much earlier than most of us would have imagined,” says Marco Leyton, an expert on the neurobiology of drug use and addictions and professor in McGill’s Department of Psychiatry.

    Researchers have known for many years that cocaine use triggers the release of dopamine, a neurotransmitter involved in the brain’s reward system. In people with addictions, cues associated with drug use create the same effect. Visual cues — such as seeing someone using cocaine — are enough to trigger dopamine release and lead to craving.

    Scientists have long believed that, as addiction progresses, cue-induced release of dopamine shifts to the dorsal striatum, a structure deep inside the brain extensively studied for its role in the way we respond to rewards.

    “This area of the brain is thought to be particularly important for when people start to lose control of their reward-seeking behaviours,” Prof. Leyton says. “The dorsal part of the striatum is involved in habits — the difference, for example, between getting an ice cream because it will feel good versus being an automatic response that occurs even when it is not enjoyable or leads to consequences that you would rather avoid, such as weight gain or serious health hazards.”

    This switch from voluntary to habitual behaviour is thought to play an important role in the development of uncontrollable and compulsive drug use and the progression to addiction,” adds Sylvia Cox, a postdoctoral researcher at the McConnell Brain Imaging Center and the paper’s first author.

    To better understand how soon this effect might be seen, Professor Leyton’s team used positron emission tomography (PET) scans to look at what happens in the dorsal striatum of recreational cocaine users.

    The scientists created highly personalized cues by filming participants ingesting cocaine in the laboratory with a friend with whom they had used the drug before. During a later session, subjects underwent a PET scan while watching the video of their friend taking cocaine. Exposure to the cocaine-related cues increased both craving and dopamine release in the dorsal striatum.

    “An accumulation of these brain triggers might bring people closer to the edge than they had realized.” The findings also underscore the “importance of providing help early” to avoid the severe effects of dependency, he adds.


  9. Bullying’s lasting impact

    May 14, 2017 by Ashley

    From the University of Delaware press release:

    A new study led by the University of Delaware found that kids who are bullied in fifth grade often suffer from depression and begin using alcohol and other substances a few years after the incidents.

    “Students who experienced more frequent peer victimization in fifth grade were more likely to have greater symptoms of depression in seventh grade, and a greater likelihood of using alcohol, marijuana or tobacco in tenth grade,” said the study’s leader, Valerie Earnshaw, a social psychologist and assistant professor in UD’s College of Education and Human Development.

    The study involved researchers from universities and hospitals in six states, who analyzed data collected between 2004 and 2011 from 4,297 students on their journey from fifth through tenth grade. The findings were published online in the medical journal Pediatrics.

    The students were from Birmingham, Alabama; Houston, Texas; and Los Angeles County, California. Forty-four percent were Latino, 29 percent were African American and 22 percent were white.

    Although peer victimization is common during late childhood and early adolescence and appears to be associated with increased substance use, few studies have examined these associations longitudinally — meaning that data is gathered from the same subjects repeatedly over several years — or point to the psychological processes whereby peer victimization leads to substance use.

    “We show that peer victimization in fifth grade has lasting effects on substance use five years later. We also show that depressive symptoms help to explain why peer victimization is associated with substance use, suggesting that youth may be self-medicating by using substances to relieve these negative emotions,” Earnshaw said.

    Impacts and interventions

    Peer victimization leads to substance use, and substance use can harm adolescent development with implications for health throughout the lifespan, Earnshaw said. Alcohol and marijuana use may interfere with brain development and can lead to injuries. Tobacco use may lead to respiratory illness, cancer and early death.

    “Youth who develop substance use disorders are at risk of many mental and physical illnesses throughout life,” Earnshaw said. “So, the substance use that results from peer victimization can affect young people throughout their lives.”

    Among the study’s findings, boys, sexual minority youth and youth living with chronic illness reported more frequent peer victimization in fifth grade. Age, obesity, race/ethnicity, household educational achievement and family income were not related to more frequent peer victimization.

    Twenty-four percent of tenth graders in the study reported recent alcohol use, 15.2 percent reported marijuana use, and 11.7 percent reported tobacco use. Sexual minority status was more strongly related to alcohol use among girls than boys; it was also related to marijuana and tobacco use among girls but not boys.

    Earnshaw used structural equation modeling — a form of statistical analysis — to examine the multiple variables across time and to test if there were relationships among them. She started working with the data in summer 2015 and finalized the model in fall 2016 in her office in UD’s Alison Hall.

    An expert in stigma research, Earnshaw wants to understand why people treat other people poorly and how this poor treatment leads to poor health, including through substance use behaviors. She hopes this latest study will enlighten pediatricians, teachers, parents — anyone in a position to help students facing peer aggression.

    “We urge pediatricians to screen youth for peer victimization, symptoms of depression and substance use,” says Earnshaw. “These doctors can offer counsel to youth and recommendations to parents and youth for approaching teachers and school staff for support. Moreover, youth experiencing depressive symptoms and substance use should be offered treatment when needed.”

    The research team’s messages also extend to teachers.

    Peer victimization really matters, and we need to take it seriously — this echoes the messages educators already have been receiving,” Earnshaw says. “This study gives some additional evidence as to why it’s important to intervene. It also may give teachers insight into why students are depressed or using substances in middle and high school.”


  10. Study examines neuroscience of craving in addiction and binge eating

    May 11, 2017 by Ashley

    From the Center for BrainHealth press release:

    A new article in JAMA Psychiatry details the first step in revealing how craving works in the brain. Scientists at the Center for BrainHealth at The University of Texas at Dallas are the first to propose a systematic and quantitative model for drug addiction research. The model focuses on craving: the intense, urgent feeling of needing or wanting drugs. Their ongoing research and subsequent findings have the potential to open a new frontier of alcohol and substance abuse treatment that may also apply to binge-eating disorders.

    Craving is considered one of the strongest predictors of relapse,” said Dr. Xiaosi Gu, who runs the Computational Psychiatry Unit at the Center for BrainHealth. “Even after an individual has broken the cycle of compulsive drug taking, craving can still persist. Although current treatment can handle a lot of the behavioral aspects of addiction, especially physical symptoms, craving is difficult to treat because it is a subject state. For example, when you are hungry, you have the urge to eat, but it is difficult to measure how compelling your urge to eat is in a quantitative way. However, if we could visualize craving activation in the brain, we would be better able to quantify and target it. We aim, with this new framework, to begin to separate craving from reward- or drug-seeking behavior.”

    Research on drug craving has traditionally centered on studying cue response. For example, a marijuana study participant typically undergoes a brain scan while being shown a picture of a bong, and researchers analyze the brain activation in response to the cue. In this scenario, the bong is a valuable item to someone who uses marijuana. However, as Dr. Gu points out, there is no way to know whether the brain activation occurs in response to the reward (an item associated with smoking marijuana) or the craving (the bong image triggers craving for marijuana).

    Dr. Gu and Dr. Francesca Filbey, also of the Center for BrainHealth and Bert Moore Chair at BrainHealth, are collaborating to identify — using a new computational model — the exact regions of the brain that encode craving. They plan to reanalyze brain scans from previous research to lay the groundwork for quantifying craving, its effects and ways to target treatments to counteract it.

    Initial results are promising, but it will take a few years and additional funding to complete reanalysis of the thousands of brain scans previously compiled through Dr. Filbey’s research as well as data from consortia to which Dr. Filbey belongs.