Following are the latest news and information resources for the various mental health topics that we cover. We hope you will find the news educational and the links in the resources section useful in helping you to get even more in-depth data.
Repeated alcohol exposure during adolescence results in long-lasting changes in the region of the brain that controls learning and memory, according to a research team at Duke Medicine that used a rodent model as a surrogate for humans.
The study, published April 27 in the journal Alcoholism: Clinical & Experimental Research, provides new insights at the cellular level for how alcohol exposure during adolescence, before the brain is fully developed, can result in cellular and synaptic abnormalities that have enduring, detrimental effects on behavior.
“In the eyes of the law, once people reach the age of 18, they are considered adult, but the brain continues to mature and refine all the way into the mid-20s,” said lead author Mary-Louise Risher, Ph.D., a post-doctoral researcher in the Duke Department of Psychiatry and Behavioral Sciences. “It’s important for young people to know that when they drink heavily during this period of development, there could be changes occurring that have a lasting impact on memory and other cognitive functions.”
Risher and colleagues, including senior author Scott Swartzwelder, Ph.D., a professor of Psychiatry and Behavioral Sciences at Duke and Senior Research Career Scientist at the Durham VA Medical Center, periodically exposed young rodents to a level of alcohol during adolescence that, in humans, would result in impairment, but not sedation. Afterward, these animals received no further exposure to alcohol, and grew into adulthood – which in rats occurred within 24 to 29 days.
Earlier studies by the Duke team and others have shown that adolescent animals exposed to alcohol grow into adults that are much less adept at memory tasks than normal animals – even with no further alcohol exposure.
What has not been known is how these impairments manifest at the cellular level in the region of the brain known as the hippocampus, where memory and learning are controlled.
Using small electrical stimuli applied to the hippocampus, the Duke team measured a cellular mechanism called long-term potentiation, or LTP, which is the strengthening of brain synapses as they are used to learn new tasks or conjure memories.
Learning occurs best when this synaptic activity is vigorous enough to build strong signal transmissions between neurons. LTP is highest in the young, and effective learning is crucial for adolescents to acquire large amounts of new memory during the transition to adulthood.
The researchers expected they would find abnormally diminished LTP in the adult rats that had been exposed to alcohol during their adolescence. Surprisingly, however, LTP was actually hyperactive in these animals compared to the unexposed rodents.
“At first blush, you would think the animals would be smarter,” Swartzwelder said. “But that’s the opposite of what we found. And it actually does make sense, because if you produce too much LTP in one of these circuits, there is a period of time where you can’t produce any more. The circuit is saturated, and the animal stops learning. For learning to be efficient, your brain needs a delicate balance of excitation and inhibition – too much in either direction and the circuits do not work optimally.”
Importantly, the LTP abnormality was accompanied by a structural change in individual nerve cells that Swartzwelder, Risher and colleagues identified. The tiny protrusions from the branches of the cells, called dendritic spines, had appeared lanky and spindly, suggesting immaturity. Mature spines are shorter and look a bit like mushrooms, refining cell-to-cell communication.
“Something happens during adolescent alcohol exposure that changes the way the hippocampus and other regions of the brain function and how the cells actually look – both the LTP and the dendritic spines have an immature appearance in adulthood,” Swartzwelder said.
Risher said this immature quality of the brain cells might be associated with behavioral immaturity. In addition to spine changes in the hippocampus, which affects learning, colleagues of the Duke group have shown structural changes in other brain regions that control impulsiveness and emotionality.
“It’s quite possible that alcohol disrupts the maturation process, which can affect these cognitive function later on,” she said. “That’s something we are eager to explore in ongoing studies.”
The researchers said additional studies would focus on the longer-term cognitive effects of alcohol on brains, along with additional cellular changes.Read article >>
Bullied high school students have greater odds for depression and suicidal thoughts than others, and they're also more likely to take weapons to school, according to three new studies.
"Teens can be the victim of face-to-face bullying in school, electronic bullying outside of the classroom and dating violence," said Dr. Andrew Adesman, senior investigator of the studies. Each experience is associated with a range of serious adverse consequences, he added.
Researchers analyzed data from a 2013 U.S. Centers for Disease Control and Prevention survey of teens in grades 9-12, and found that depression and suicidal thoughts are much more common among teens who have been bullied electronically or at school.
Those risks were highest among teens who experienced both forms of bullying, according to one of the three studies. All are scheduled for presentation Monday at the Pediatric Academic Societies annual meeting in San Diego.
"Although cyberbullying may not pose the same physical threat that face-to-face bullying does, it can be far more hurtful since it can spread like wildfire throughout a student body and take on a life of its own," Adesman, chief of developmental and behavioral pediatrics at Cohen Children's Medical Center in New Hyde Park, N.Y., said in a hospital news release.
Another study found that bullying and physical and/or sexual violence on dates were associated with teens carrying weapons to school or not going to school.
Bullying and dating violence are more common than many believe, according to study principal investigator Alexis Tchaconas, a research associate at Cohen Children's Medical Center.
"The CDC reports that 11 percent of high school students experience dating violence, and 20 percent report being bullied," she said in the news release. "Greater prevention efforts are needed to protect the mental health and physical well-being of our teens."
The third study found that among teens who were victims of bullying in the past 12 months, girls were more likely to carry weapons to school than girls who were not victimized. But it's not clear if girls who have been victimized carry weapons for self-defense or revenge.
Principal investigator Tammy Pham, who conducted the research as an intern at Cohen Children's, said it's important to find ways to prevent all types of bullying.
"Students need to feel safe both in and outside of school. More needs to be done to reduce bullying and the huge toll it takes on youth," Pham said in the news release.
The studies only show a link, not a direct cause-and-effect relationship, between bullied teens and developing mental health problems. Also, data and conclusions presented at meetings are usually considered preliminary until published in a peer-reviewed medical journal.Read article >>
A research team headed by a Rhode Island Hospital psychiatrist reveals that persons who live with borderline personality disorder, or BPD, experience physical and mental difficulties that rival those associated with the more prevalent and better-known bipolar disorder.
Dr. Mark Zimmerman’s study was published this week in the online edition of the British Journal of Psychiatry. BPD is a severe emotional disorder characterized by impulsive behaviors, anger, irritability, poor self image and fear of abandonment.
“The level of psychosocial morbidity and suicidality associated with BPD is as great, or greater, than that experienced by patients with bipolar disorder,” Zimmerman, director of outpatient psychiatry at Rhode Island Hospital and director of the Rhode Island Methods to Improve Diagnostic Assessment and Services (MIDAS) project, said in a release.
“From a public health perspective, improving the detection and treatment of BPD is as imperative as diagnosing and treating bipolar disorders.”
According to National Institute of Mental Health statistics cited by Rhode Island Hospital, an estimated 1.6 of Americans are diagnosed with borderline personality disorder, compared to an estimated 2.6 percent who live with bipolar disorder.
“Despite the clinical and public health significance of both of these disorders, it sometimes seems as if BPD lives in the shadow of bipolar disorder,” said Zimmerman. “Bipolar disorder is a widely researched, well-publicized, well-funded topic. By contrast, BPD is seldom discussed and it is not included in the Global Burden of Disease study, a comprehensive registry that quantifies diseases by cost, mortality, geography, risk and other factors.”
Zimmerman is a faculty member of the Alpert Medical School of Brown University’s department of psychiatry and human behavior. Joining him from that department on the study were William Ellison, Theresa A. Morgan, Diane Young, Iwona Chelminski, and Kristy Dalrymple.Read article >>
A team led by Case Western Reserve researchers has identified a potentially powerful approach to lowering relapse rates among the ranks of those addicted to illegal drugs or alcohol.
In a study of nearly 200 teenagers admitted to a residential treatment center in the northeastern United States, psychiatry professor Maria Pagano, PhD, confirmed both the prevalence of social anxiety issues among them as well as the benefits of measures designed to alleviate social distress. These findings were posted online this month in the journal Alcoholism: Clinical and Experimental Research.
Pagano found that 42 percent of youths in the study acknowledged severe social fears and 15 percent of youths in the study met diagnostic criteria for social anxiety disorder. Social anxiety disorder preceded initial use of alcohol and other drugs by an average of two years.
“Drinking and drug use relieved a pervasive sense of not fitting in for many youths addicted to alcohol and illicit drugs, and hypersensitivity to criticism is common,” said lead author Pagano, Associate Professor of Psychiatry, Case Western Reserve University School of Medicine. “The incidence of higher rates of heroin use among young adults living in this region is distressing. A sense of belonging is important to live sober and to thrive, and 12-step service offers a venue for those impaired by social anxiety.”
Along with colleagues at Case Western Reserve, Baylor University and the University of Akron, Pagano examined the participation of youths in Alcoholics Anonymous service activities, such as setting up chairs or making coffee, as a way to facilitate the youths transition back into the community following treatment and a sober peer group. Service participation during treatment was higher among youths with social anxiety and cut the risk of relapse and incarceration approximately in half in the six months post-treatment. Forty-three percent of youths with social anxiety were high helpers during treatment, compared to 30 percent of youths without social anxiety.
Pagano and her colleagues noted that most formal treatment modalities are delivered in groups that can trigger the fear of negative peer appraisal among those with social anxiety. That’s where service activities can be particularly useful for those with social anxiety. Service activities allow for conversations to occur naturally, do not involve speaking in front of others, and allow youths to contribute and benefit from the 12-step program.
Youths with social anxiety who did not get active in service during treatment had the greatest risk of relapse, whereas high helpers with or without social anxiety were less likely to relapse and be incarcerated post-treatment.
“Low-intensity service is a more gentle way for youths to feel like they belong and to connect with other people who are facing similar challenges,” Pagano said. “Getting active in helping others through AA motivates them to stay long enough to benefit from other AA activities and increase their chances of turning their life around toward a positive life trajectory.”
Engaging with a caring network of people encourages ongoing attendance at AA meetings, particularly during the high-risk six months after treatment when 60 to 90 percent relapse and AA meeting attendance dramatically declines.
Pagano also recommended a full diagnostic evaluation of youths entering addiction treatment who appear to be socially anxious. These evaluations may lead to a definitive diagnosis of social anxiety disorder and an opportunity to treat affected adolescents with medication.
The inspiration for this investigation came from Pagano’s observation in her earlier work with adults and adolescents suffering addiction where a commonly described ailment is feeling like a social misfit. The closest condition she could find to the feeling of not belonging was social anxiety disorder. In future research, Pagano plans to assess and quantify the feeling of not fitting in — a social misfit syndrome, of sorts — and how that relates to substance addiction.
“Social anxiety disorder is the most common anxiety disorder among individuals with addiction,” Pagano said. “I believe the feeling of being a social misfit is lurking behind social anxiety and is common among those suffering with the disease of addiction.”Read article >>
Depression is causing a lot more damage to your body than previously thought, researchers discovered.
Researchers from the Wellcome Trust Centre for Human Genetics have found conclusive evidence which suggests that, apart from wreaking havoc in our brains, depression can also alter our DNA. Moreover, prolonged illness can even badly influence our cells, messing with their ability to generate energy.
The researchers made the discovery after investigating the genomes of more than 11,500 women. Initially, the team had hoped to zero-in on the genes that might contribute to the risk of depression. However, they started noticing peculiar patterns, predominantly a series of metabolic changes in the patients’ cells that seem to have been caused by the onset of depression.
The most critical discovery was that women who had stress-related depression — depression that’s associated with some kind of adversity during childhood, such as sexual abuse — had more mitochondrial DNA (mtDNA) than their mentally healthy and emotionally stable peers.
Mitochondria, the cells that have been largely associated with power generation within our bodies and have appeared in multiple other studies, are classified as “powerhouse organelles.” They are responsible for providing energy for the rest of the cell. The researchers noted a remarkable increase in mitochondrial DNA, which led them to summarize that the energy needs of their cells had changed significantly, primarily as a direct response to stress typically observed during depression.
Additionally, the researchers also found that the women with stress-related depression had shorter telomeres than the healthy women. Telomeres are caps at the end of our chromosomes that shorten naturally as we age, but the rapid shortening may have been due to depression-induced stress, think the researchers.
Though circumstantial correlation doesn’t necessarily equal causation, the researchers were able to prove their hypothesis by putting mice under stress and monitoring any genetic and cellular changes that occurred. As expected, those mice which were under stress not only showed an increase in mtDNA, but they also had shorter telomeres than the normal lab mice.
The researchers strongly believe that that changes our bodies undergo when under stress are a metabolic response. Fortunately for us humans, the research indicated that that the effects of stress are also partially reversible.
Though the researchers admit they have merely been able prove the relationship between the molecular markers and depression, their work is essential to show that emotional turmoil also affects us on a biological level. In other words, depression can herald a lot of physical ailments, too.Read article >>
The darkest day of Marjorie Stowe's depression came when her long-time psychiatrist told her she obviously was choosing to resist the healing effects of one medication after another, psychotherapy, electric shock. "You must be getting some emotional payoff that prevents you from letting your depression go," he said. "Secretly, you must enjoy being this way."
What's left when your own psychiatrist gives up on you? During the day, praying helped her hold on. At night, she prayed not to wake up.
Growing up in Franklin Springs, Georgia, the youngest of a Pentecostal minister's six children, Stowe was a serious, unsmiling child. She graduated from hometown Emmanuel College, took pre-pharmacy courses at the University of Hawaii, and earned a PharmD from Campbell University in North Carolina. She managed it all — school, then work and marriage — with the help of antidepressants.
Her plunge into suicidal darkness began at 39, after the birth of her daughter. Could it be hormonal? Her gynecologist shook her head, then told Stowe about an Emory neurologist named Helen Mayberg she had just read about, who was doing a special type of brain surgery with electrodes for treatment-resistant depression, with promising results. You have a physical illness of the brain, the gynecologist said. This might be your best hope.
Fifteen percent of Americans have clinical depression during some portion of their lives. A third of those have major depression: suicidal thoughts, a sense of disconnection from the world. For a few of those, the entire arsenal of traditional treatments — therapy, medications, even electroconvulsive therapy — doesn't work. These are the patients Mayberg sees.
Stowe was a model case. Indeed, her long-term depression was so severe, it made it difficult for her to gather the required documentation and go through the long psychiatric interviews.
The day of surgery, Emory neurosurgeon Robert Gross implanted very thin wires with tiny electrodes in two small lobes deep at the midline of Stowe's brain.
Mayberg stood beside Gross, quietly talking to Stowe, guiding her through the process as she often does with patients. Gross was the surgeon, Mayberg the architect and team leader. Precisely where Gross placed the electrodes was based on Mayberg's extensive brain maps, both of activity in different regions of the brains of depressed patients and of the neural cables that connect these regions, allowing communication between them. Stowe was awake to report any sensations when the electrodes were activated. (It's not as bad as it sounds, since the brain has no pain receptors.)
The electrodes' job is to deliver a small amount of electrical current to the specific region of the brain Mayberg discovered is overactive in people with depression. This region, Area 25, serves as a kind of junction box, so adjusting activity here is like tuning the entire depression circuitry. The electrodes are connected to an implantable pulse generator (IPG), a pacemaker-like device placed under Stowe's collarbone. The IPG keeps a steady stream of low voltage flowing into the patient's brain.
As the electrodes are tested in the OR, patients often report an emotional weight being lifted instantaneously—one way the team knows the electrode is in the right place. Within a week after surgery, with the electrical current flowing continuously, Stowe began to notice sunlight, birdsong. Her sense of humor returned. Her boss didn't recognize her on the phone, so changed was her voice.
Two years later, Stowe says the procedure has been transformative. "It brought me out of the pit," she says. "People who haven't been there can't understand what a gift it is to feel joy. I always loved my family. Now I enjoy them."
Her 5-year-old daughter, Maddie, doesn't remember the mommy who cried every day, only the happy one involved in her life. They enjoy horseback riding, playing in the park, and getting mani-pedis on girls' days out. Before deep brain stimulation (DBS), Stowe felt completely dependent on her husband, Jeff, a Home Depot project manager. After the procedure, she feels like an equal partner—and it's fun, she says: "Laughing like we used to, motorcycles, camping, Georgia Tech football, happy times with my daughter and stepsons, Joshua, Sean, and Zachary."
She recently started training for a 5-K race, determined to be as healthy physically as she now feels mentally. Jeff refers to her as "the new and improved version."
This major shift in mood and energy level took some getting used to, however. "After 30 years in a kind of prison, it was a big adjustment to suddenly be well," says Stowe. "I didn't know what to do, what to feel." The research team's responsibility doesn't end in the OR, says Mayberg. Stowe receives ongoing treatment from behavioral therapist Cynthia Romero, psychiatrist Patricio Riva Pose, and the rest of the DBS research team.
Now that Stowe's brain is able to focus, thanks to the "reset" of DBS, she is learning to enjoy the moment, to not dread the future, and — hardest of all, she says — to let go of the guilt about what her family went through during her illness.Read article >>
For many older adults, the thought of stepping into a yoga class swarming with yogis more flexible than Gumby might provoke anxiety. But the practice itself may be just the antidote the over-60 set needs, suggests a recent review of studies about relaxation exercises. Those who did yoga and other calming activities saw greater reductions in their anxiety and depression than people who didn’t.
The body of literature on yoga’s relaxation benefits spans all kinds of people, but the authors thought adults aged 60 and older deserved their own analysis. Up to 40% of older adults report anxiety, they note, and anywhere from 15-20% of the elderly experience depression. So in the review published in the journal Aging & Mental Health, researchers scrutinized 15 studies—12 of them randomized controlled trials—from the past two decades that looked at different methods of relaxation. They gauged the effectiveness of six techniques: yoga, listening to music, tensing and relaxing different groups of muscles, massage therapy and stress management training.
The most effective ways to alleviate depression were yoga, the music intervention and the muscle tensing and relaxing exercise—called PMRT, for progressive muscle relaxation training. The music and yoga interventions were the best for anxiety.
Yoga had the strongest staying power. Positive effects from the stretching, breathing and meditation exercises stuck around six months later in older adults. “It could help counterbalance the negative effects of ageing, improve physical functioning, postpone disability, decrease morbidity and mortality, stimulate the mind, and increase hope, reducing the risk of anxiety and depression,” the study authors write.
And good vibes from PMRT lasted 14 weeks after the intervention ended. “It is believed that the PMRT has a tranquilising effect, triggers a sense of peacefulness, helps participants retreat mentally from their problem and curtails negative thoughts, reducing depressive symptoms,” the authors write.
The most effective intervention, of course, is the one you enjoy doing—and these results suggest that it’s never too late to find your favorite way to unwind.Read article >>
When it comes to being a good mom or dad, there’s a fine line between good parenting and smothering your children by being overprotective.
A new study carried out at by scientists at the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) at King’s College London has concluded that such parenting can be bad for kids, as anxiety is “catching” and can be passed down.
As the study focused on on parents who were identical twins as well as non-identical twins, researchers were able to distinguish in the study between the influence on children’s anxiety as a result of genes as well as their environment growing up.
One of the members involved in the study, Dr Robert Freedman explained.
“This study is a landmark, because it is the first to clearly establish the early transmission of anxiety symptoms from parents to children, not through their shared genetic background, but rather from the way in which anxious parents raise their children. Parents who are anxious can now be counselled and educated on ways to minimise the impact of their anxiety on the child’s development.”
Conditions among children such as anxiety disorder tend to start when a kid is around 11 and can have a huge impact on that child’s life in the future.
The head author of the study, Professor Thalia Elay, said that parents don’t have to pass their anxieties onto their kids, “Our research shows that even if you have had to cope with high levels of anxiety yourself, it is not inevitable that this will follow in your children. There are many things that can be done at home to prevent or reduce anxiety in children and adolescents.”
Elay added, “While a natural tendency when your child is anxious is to try to protect them, it can be more helpful to support them in taking small age-appropriate risks. This will teach them that the world is generally a safe place and they can manage situations that initially seem stressful, developing their sense of mastery and in turn promoting resilience.”
To that end, according to Elay, more research is needed in order to clarify whether anxiety in children and adolescents elicits anxiety in parents, “This would help us decide whether to focus intervention largely at the parent or child level,” she said.Read article >>
There’s been an increasingly compelling pile of evidence that mindfulness training has effects on both brain and behavior—and its potential for treating depression is among its more promising uses. A new study from the University of Oxford finds that mindfulness-based cognitive therapy (MBCT) is just as effective as antidepressants for preventing a relapse of depression, which affects 50-80% of people who experience a first bout of depression. This may not be entirely surprising, since previous studies have hinted at similar results. But what’s encouraging here is that MBCT may be an effective way to wean people off even successful courses of antidepressants, should they want or need to get off them in the future, without the high risk of relapse.
The team, who published their findings in The Lancet, followed 424 people who were already on antidepressants for major depression. They had them either continue taking the meds for “maintenance” (to prevent relapse) or titrate off while at the same time learning MBCT. The people in the latter group had eight group sessions of MBCT, were given instructions about how to practice on their own, and had four in-person follow-up appointments over the course of a year.
Here’s a little about MBCT: the practice marries mindfulness meditation (or mindfulness training) and cognitive behavior therapy (CBT), which are quite related to begin with. With mindfulness, an individual learns to observe his or her own thoughts with curiosity and without judgment, acknowledge them, and then let them go. Similarly, with CBT, people learn to identify their own negative or destructive thought patterns and replace them, over time, with more productive and positive ones. The two merge naturally and, as MBCT, are thought to be very effective for depression, since intrusive and ruminative thoughts can be some of the central and most crippling symptoms.
And the results from the current study were impressive: MBCT was just as effective as staying on antidepressants over the next two years following treatment: 44% of people in the MBCT group relapsed, while 47% of those in the antidepressant group did.
From their earlier work, the researchers had anticipated that MBCT might actually be more effective than medication in preventing relapse. Although that wasn’t the result of the current study, MBCT was still just as effective as medication, which is good news for those who in principle would like to go off it.
That a meditation-based practice might be as effective as medication for treating depression is not new. In a meta-analysis from Johns Hopkins last year, looking back over many studies on meditation and depression, the effect size for meditation was found to be 0.3, which is largely the same as for antidepressants. This also suggests that meditation might rival medication for actually treating depression – not just preventing relapse, as in the current study. Perhaps not for everyone, but for some.
“Compared to other skills that we train in,” says Madhav Goyal, author of this earlier study, “the amount of training received by the participants in the trials was relatively brief. Yet, we are seeing a small but consistent benefit for symptoms of anxiety, depression, and pain. So you wonder whether we might see larger effects with more training, practice, and skill.”
And that’s the other important finding of the current study: The cost was about the same for both treatments – often a concern with any form of “talk therapy” is that it may be costly more than meds, since multiple visits with trained professionals are required. But this was not the case – perhaps partly because the study used group sessions of MBCT – which gives more fuel to psychosocial treatments being as effective as drug therapies on multiple levels.
The study brings some interesting and hopeful news for those who don’t want to take medication over the long term, or who can’t tolerate the side effects. And, the authors point out, some people just prefer psychosocial treatments over drug treatments for personal reasons. Always speak with your mental health provider before changing or stopping therapies. Since 350 million people worldwide are affected by depression, and it’s one of the leading causes of disability in the world, finding alternative ways to prevent relapse from happening is critically needed. And MBCT, in the right circumstances, might be one of the more effective alternatives.Read article >>
In a promising breakthrough for smokers who are trying to quit, neuroscientists at UMass Medical School and The Scripps Research Institute have identified circuitry in the brain responsible for the increased anxiety commonly experienced during withdrawal from nicotine addiction.
“We identified a novel circuit in the brain that becomes active during nicotine withdrawal, specifically increasing anxiety,” said principal investigator Andrew Tapper, PhD, associate professor of psychiatry at UMMS. “Increased anxiety is a prominent nicotine withdrawal symptom that contributes to relapse in smokers attempting to quit.”
The study yielded several discoveries about interconnected brain mechanisms that induce anxiety during nicotine withdrawal and possible ways to derail these mechanisms in order to treat or even prevent the especially troublesome symptom.
Experiments leading to the multiple related findings were conducted over several years by the laboratories of Dr. Tapper; Paul Gardner, PhD, professor of psychiatry at UMMS; and collaborator Olivier George, PhD, assistant professor in the Committee on Neurobiology of Addictive Disorder at The Scripps Research Institute of La Jolla, Cal. The lead author was Rubing Zhao-Shea, MD, research assistant professor of psychiatry at UMMS.
Published online by Nature Communications on April 21, the study found that a brain region called the interpeduncular nucleus is activated and appears to cause anxiety during nicotine withdrawal. Investigators were intrigued to learn that the sub-region of the interpeduncular nucleus that is activated and linked to anxiety during withdrawal is distinct from another sub-region, previously identified by Tapper, where physical nicotine withdrawal symptoms such as headaches, nausea and insomnia originate.
Anxiety is an affective symptom often likely to thwart smokers’ attempts to quit. The newly discovered sub-region offers a distinct target for dampening the affective symptoms of nicotine withdrawal.
Also newly identified is the fact that input from neurons in two other brain regions converge onto the interpeduncular nucleus to stimulate anxiety-provoking neurons. Surprisingly, the ventral tegmental area, which is traditionally associated with the rewarding or pleasurable effects of abused drugs, activates neuron receptors through corticotropin releasing factor, a protein neurotransmitter released in response to stress. Also surprising, neurons in the medial habenula stimulate interpeduncular nucleus neurons by releasing glutamate, the major excitatory neurotransmitter in the brain, an effect that is increased by corticotropin releasing factor receptor activation.
“Both of these inputs are important. We could alleviate anxiety during nicotine withdrawal by either preventing corticotropin releasing factor synthesis in the ventral tegmental area, or by silencing the medial habenula inputs into the interpeduncular nucleus,” said Tapper.
Investigators were able to alleviate anxiety in mice by quieting the activity of those activated neurons, suggesting the same might be possible for humans.
“There are already drugs that block the CRF receptor that contributes to activation of these anxiety-inducing neurons,” Tapper noted. “These receptors have previously been linked to anxiety and depression, so our findings may also have implications for anxiety disorders in general.”
Next steps for this research collaboration will be expanding the scope of scientists’ understanding of the interactions between anxiety, stress, reward and withdrawal from addictive substances.
“We’re now exploring whether the circuitry that we identified is involved in stress-induced anxiety in general, or specific to nicotine withdrawal-induced anxiety,” Tapper said. “We’re also exploring if this circuitry is engaged with other drugs of abuse.”Read article >>