Mindful movement may help lower stress, anxiety
June 21, 2018
Science Daily/Penn State
Taking a walk may be a good opportunity to mentally review your to-do list, but using the time to instead be more mindful of your breathing and surroundings may help boost your wellbeing, according to researchers who found that while students reported being less stressed while they were on their feet and moving, they received an even greater benefit when they reported also being more mindful.
The researchers found that while students reported being less stressed while they were on their feet and moving, they received an even greater benefit when they reported also being more mindful.
Chih-Hsiang "Jason" Yang, a postdoctoral scholar at the University of Southern California who led the study while earning his doctorate at Penn State, said the results suggest a simple way for people to boost their wellbeing throughout the day.
"It can be difficult to ask people to spend a lot of time doing moderate or vigorous activity by going to the gym or out for a run, especially if they feel stressed," Yang said. "But if they don't need to change their everyday behavior, and can instead try to change their state of mind by becoming more mindful, they can probably see this beneficial effect. You don't need to exert a lot of extra effort in order to improve your wellbeing by being more mindful while you're moving around."
David Conroy, professor of kinesiology at Penn State, also said the findings -- recently published in the journal Psychology of Sports and Exercise -- could help people who are not able to engage in strenuous exercise.
"If someone is looking for a way to manage these kinds of feelings, it may be worth trying some sort of mindful movement," Conroy said. "This option may be especially beneficial for people who don't enjoy exercise and would prefer a less intense form of physical activity."
According to the American College Health Association, more than half of college students experience anxiety, sadness or mental exhaustion at least once a year, suggesting a need for a simple way to reduce these negative states. Because students are often moving throughout their days, as they walk to class and go about other activities, the researchers wanted to see if there was a connection between mindfulness, movement and a reduction in negative states.
The researchers recruited 158 Penn State students for the study. For two weeks, a special mobile phone app, called Paco, randomly prompted the participants eight times a day to answer questions about their current activity and states of mind. The prompts included questions about where the participant was, if they were moving, and if they were stressed or anxious, as well as questions designed to assess mindfulness.
After analyzing the data, the researchers found that in the moments when participants were more mindful or active than usual, they showed reduced negative affect. They also found a possible synergistic effect when people were both mindful and active.
"When people were both more mindful and more active than usual, they seem to have this extra decrease in negative affect," Yang said. "Being more active in a given moment is already going to reduce negative affect, but by also being more mindful than usual at the same time, you can see this amplified affect."
Conroy said it was interesting to see patterns emerge within the individual participants, instead of just comparing people who are generally more mindful to people who are generally less mindful.
"Most studies in this area have focused on the differences between people who are more versus people who are less mindful, but we saw that college students often slipped in and out of mindful states during the day," Conroy said. "Developing the ability to shift into these states of mindfulness as needed may be valuable for improving self-regulation and well-being."
To better explore the causal role of mindfulness on lower negative states of being, Yang completed a second study, in which older adults who participated in an outdoor mindfulness activity then reported on their feelings of stress, anxiety and depression. Yang found that the mindful walking was associated with lower levels of these feelings.
The researchers said that in the future, studies that collect more objective data -- like gathering information about physical activity by using accelerometers -- and include more varied populations could be useful.
https://www.sciencedaily.com/releases/2018/06/180621112007.htm
Lingering negative responses to stress linked with health a decade later
April 9, 2018
Science Daily/Association for Psychological Science
People whose negative emotional responses to stress carry over to the following day are more likely to report health problems and physical limitations later in life compared with peers who are able to 'let it go.'
"Our research shows that negative emotions that linger after even minor, daily stressors have important implications for our long-term physical health," says psychological scientist Kate Leger of the University of California, Irvine.
"When most people think of the types of stressors that impact health, they think of the big things, major life events that severely impact their lives, such as the death of a loved one or getting divorced," Leger says. "But accumulating findings suggest that it's not just the big events, but minor, everyday stressors that can impact our health as well."
Evidence from previous studies suggests a clear association between same-day responses to stress and long-term well-being, but the impact of lingering emotional responses remained unclear. That is, does it make a difference if a stressor -- such as a flat tire, a bad grade, or an argument -- leads to negative emotions that spill over into the following day?
To find out, Leger and colleagues Susan T. Charles and David M. Almeida analyzed data from the Midlife in the United States Survey, a nationally representative, longitudinal study of adults.
As part of the study, participants completed an 8-day survey of negative emotion; each day, they reported how much of the time over the previous 24 hours they had felt a variety of emotions (e.g., lonely, afraid, irritable, and angry). They also reported the stressors that they experienced each day.
In a subsequent part of the study that took place 10 years later, the participants completed surveys that assessed their chronic illnesses and functional limitations. Participants reported the degree to which they were able to carry out basic and everyday tasks, such as dressing themselves, climbing a flight of stairs, carrying groceries, and walking several blocks.
As expected, people tended to report higher negative emotion if they had experienced a stressor the previous day compared with if they hadn't experienced any stressor the day before.
Critically, analyses revealed that lingering negative emotions in response to a stressor were associated with a greater number of health problems, including chronic illnesses, functional impairments, and difficulties with everyday tasks, a decade later.
These associations emerged independently of participants' gender, education, and baseline health and they held even after the researchers took participants' same-day emotional responses and average number of stressors into account.
"This means that health outcomes don't just reflect how people react to daily stressors, or the number of stressors they are exposed to -- there is something unique about how negative they feel the next day that has important consequences for physical health," explains Leger.
Leger and colleagues hypothesize that this link could play out through activation of stress-related systems or through health behaviors, two potential mechanisms that offer avenues for future research.
"Stress is common in our everyday lives. It happens at work, it happens at school, it happens at home and in our relationships," says Leger. "Our research shows that the strategy to 'just let it go' could be beneficial to our long term physical health."
https://www.sciencedaily.com/releases/2018/04/180409161315.htm
Is your stress changing my brain?
Stress isn't just contagious; it alters the brain on a cellular level
March 8, 2018
Science Daily/University of Calgary
Scientists have discovered that stress transmitted from others can change the brain in the same way as a real stress does.
In a new study in Nature Neuroscience, Jaideep Bains, PhD, and his team at the Cumming School of Medicine's Hotchkiss Brain Institute (HBI), at the University of Calgary have discovered that stress transmitted from others can change the brain in the same way as a real stress does. The study, in mice, also shows that the effects of stress on the brain are reversed in female mice following a social interaction. This was not true for male mice.
"Brain changes associated with stress underpin many mental illnesses including PTSD, anxiety disorders and depression," says Bains, professor in the Department of Physiology and Pharmacology and member of the HBI. "Recent studies indicate that stress and emotions can be 'contagious'. Whether this has lasting consequences for the brain is not known."
The Bains research team studied the effects of stress in pairs of male or female mice. They removed one mouse from each pair and exposed it to a mild stress before returning it to its partner. They then examined the responses of a specific population of cells, specifically CRH neurons which control the brain's response to stress, in each mouse, which revealed that networks in the brains of both the stressed mouse and naïve partner were altered in the same way.
The study's lead author, Toni-Lee Sterley, a postdoctoral associate in Bains' lab said, "What was remarkable was that CRH neurons from the partners, who were not themselves exposed to an actual stress, showed changes that were identical to those we measured in the stressed mice."
Next, the team used optogenetic approaches to engineer these neurons so that they could either turn them on or off with light. When the team silenced these neurons during stress, they prevented changes in the brain that would normally take place after stress. When they silenced the neurons in the partner during its interaction with a stressed individual, the stress did not transfer to the partner. Remarkably, when they activated these neurons using light in one mouse, even in the absence of stress, the brain of the mouse receiving light and that of the partner were changed just as they would be after a real stress.
The team discovered that the activation of these CRH neurons causes the release of a chemical signal, an 'alarm pheromone', from the mouse that alerts the partner. The partner who detects the signal can in turn alert additional members of the group. This propagation of stress signals reveals a key mechanism for transmission of information that may be critical in the formation of social networks in various species.
Another advantage of social networks is their ability to buffer the effects of adverse events. The Bains team also found evidence for buffering of stress, but this was selective. They noticed that in females the residual effects of stress on CRH neurons were cut almost in half following time with unstressed partners. The same was not true for males.
Bains suggests that these findings may also be present in humans. "We readily communicate our stress to others, sometimes without even knowing it. There is even evidence that some symptoms of stress can persist in family and loved ones of individuals who suffer from PTSD. On the flip side, the ability to sense another's emotional state is a key part of creating and building social bonds."
This research from the Bains lab indicates that stress and social interactions are intricately linked. The consequences of these interactions can be long-lasting and may influence behaviours at a later time.
https://www.sciencedaily.com/releases/2018/03/180308143212.htm
Stress can lead to risky decisions
Neuroscientists find chronic stress skews decisions toward higher-risk options
November 16, 2017
Science Daily/Massachusetts Institute of Technology
Making decisions that require weighing pros and cons of two choices is dramatically affected by chronic stress, neuroscientists have discovered. In a study of rats and mice, they found stressed animals were far likelier to choose high-risk, high-payoff options. They also found that impairments of a specific brain circuit underlie this abnormal decision making.
MIT neuroscientists have now discovered that making decisions in this type of situation, known as a cost-benefit conflict, is dramatically affected by chronic stress. In a study of mice, they found that stressed animals were far likelier to choose high-risk, high-payoff options.
The researchers also found that impairments of a specific brain circuit underlie this abnormal decision making, and they showed that they could restore normal behavior by manipulating this circuit. If a method for tuning this circuit in humans were developed, it could help patients with disorders such as depression, addiction, and anxiety, which often feature poor decision-making.
"One exciting thing is that by doing this very basic science, we found a microcircuit of neurons in the striatum that we could manipulate to reverse the effects of stress on this type of decision making. This to us is extremely promising, but we are aware that so far these experiments are in rats and mice," says Ann Graybiel, an Institute Professor at MIT and member of the McGovern Institute for Brain Research.
Graybiel is the senior author of the paper, which appears in Cell on Nov. 16. The paper's lead author is Alexander Friedman, a McGovern Institute research scientist.
Hard decisions
In 2015, Graybiel, Friedman, and their colleagues first identified the brain circuit involved in decision making that involves cost-benefit conflict. The circuit begins in the medial prefrontal cortex, which is responsible for mood control, and extends into clusters of neurons called striosomes, which are located in the striatum, a region associated with habit formation, motivation, and reward reinforcement.
In that study, the researchers trained rodents to run a maze in which they had to choose between one option that included highly concentrated chocolate milk, which they like, along with bright light, which they don't, and an option with dimmer light but weaker chocolate milk. By inhibiting the connection between cortical neurons and striosomes, using a technique known as optogenetics, they found that they could transform the rodents' preference for lower-risk, lower-payoff choices to a preference for bigger payoffs despite their bigger costs.
In the new study, the researchers performed a similar experiment without optogenetic manipulations. Instead, they exposed the rodents to a short period of stress every day for two weeks.
Before experiencing stress, normal rats and mice would choose to run toward the maze arm with dimmer light and weaker chocolate milk about half the time. The researchers gradually increased the concentration of chocolate milk found in the dimmer side, and as they did so, the animals began choosing that side more frequently.
However, when chronically stressed rats and mice were put in the same situation, they continued to choose the bright light/better chocolate milk side even as the chocolate milk concentration greatly increased on the dimmer side. This was the same behavior the researchers saw in rodents that had the prefrontal cortex-striosome circuit disrupted optogenetically.
"The result is that the animal ignores the high cost and chooses the high reward," Friedman says.
Circuit dynamics
The researchers believe that this circuit integrates information about the good and bad aspects of possible choices, helping the brain to produce a decision. Normally, when the circuit is turned on, neurons of the prefrontal cortex activate certain neurons called high-firing interneurons, which then suppress striosome activity.
When the animals are stressed, these circuit dynamics shift and the cortical neurons fire too late to inhibit the striosomes, which then become overexcited. This results in abnormal decision making.
"Somehow this prior exposure to chronic stress controls the integration of good and bad," Graybiel says. "It's as though the animals had lost their ability to balance excitation and inhibition in order to settle on reasonable behavior."
Once this shift occurs, it remains in effect for months, the researchers found. However, they were able to restore normal decision making in the stressed mice by using optogenetics to stimulate the high-firing interneurons, thereby suppressing the striosomes. This suggests that the prefronto-striosome circuit remains intact following chronic stress and could potentially be susceptible to manipulations that would restore normal behavior in human patients whose disorders lead to abnormal decision making.
"This state change could be reversible, and it's possible in the future that you could target these interneurons and restore the excitation-inhibition balance," Friedman says.
https://www.sciencedaily.com/releases/2017/11/171116132746.htm
Older Adults Who Sleep Poorly React to Stress with Increased Inflammation
March 1, 2012
Science Daily/University of Rochester Medical Center
Older adults who sleep poorly have an altered immune system response to stress that may increase risk for mental and physical health problems, according to a study led by a University of Rochester Medical Center researcher.
In the study, stress led to significantly larger increases in a marker of inflammation in poor sleepers compared to good sleepers -- a marker associated with poor health outcomes and death.
"This study offers more evidence that better sleep not only can improve overall well-being but also may help prevent poor physiological and psychological outcomes associated with inflammation," said Kathi L. Heffner, Ph.D., assistant professor of Psychiatry at the Medical Center.
Poor sleepers reported more depressive symptoms, more loneliness and more global perceived stress relative to good sleepers. Poor sleepers did not differ from good sleepers when IL-6 was measured before the tests began. Across the group, the participants showed increases in IL-6. However, poor sleepers had a significantly larger increase in IL-6 in response to the stressful tests compared to good sleepers, as much as four times larger and at a level found to increase risk for illness and death in older adults.
A further analysis of the results for the impact of loneliness, depression or perceived stress on IL-6 levels found no association. Poor sleep stood as the predictor of elevated inflammation levels.
"We found no evidence that poor sleep made them deal poorly with a stressful situation. They did just as well on the tests as the good sleepers. We did not expect that," Heffner said. "We did find that they were in a worse mood after the stressor than a good sleeper, but that change in mood did not predict the heightened inflammatory response."
As people age, a gradual decline in the immune system occurs along with an increase in inflammation. Heightened inflammation increases the risk for cardiovascular disease, diabetes and other illnesses, as well as psychiatric problems.
While relatively little is known about the pathways through which poor sleep impacts circulating levels of inflammatory proteins, the study led by Heffner provides a clinical target for preventing poor outcomes for older adults.
"There are a lot of sleep problems among older adults," Heffner said. "Older adults do not have to sleep poorly. We can intervene on sleep problems in older adulthood. Helping an elderly person become a better sleeper may reduce the risk of poor outcomes associated with inflammation."
http://www.sciencedaily.com/releases/2012/03/120301103758.htm
Alcohol-related cues, stress strongly impact females and increase 'craving'-like behavior
April 1, 2015
Science Daily/Federation of American Societies for Experimental Biology (FASEB)
A study conducted in rats measuring risk factors that contribute to alcohol abuse suggests females are particularly sensitive to alcohol-related cues and stress which elicits a “craving” response.
"Traditionally, heavy drinking has been shown to be more prevalent in men, though more recent studies point to a narrowing in the gender gap," said Megan Bertholomey, Ph.D., a postdoctoral associate in the laboratory of Mary Torregrossa, Ph.D., at the University of Pittsburgh who conducted the research. "Further, alcohol-dependent women tend to show more negative emotional responses to drinking, including greater stress and anxiety."
To investigate sex differences in the role stress plays in alcohol abuse, the researchers first trained male and female rats to press a lever, which would then administer alcohol simultaneously paired with an audiovisual cue. After three weeks of drinking, the rats associated the cue with alcohol.
The rats then underwent a period of abstinence with no audiovisual cue and no alcohol intake; regardless of how many times they pressed the lever. However, those original alcohol-cue memories do not go away during abstinence, allowing the researchers to determine factors that can cause the rats to start responding again.
"It's well established that exposure to alcohol-associated cues and to stress can lead to reinstatement of the drug seeking response, which is thought to be a model of craving or relapse in rats," said Bertholomey, who will present the research at the American Society for Pharmacology and Experimental Therapeutics (ASPET) Annual Meeting during Experimental Biology 2015.
Prior studies show that exposure to both cues and stress can have an additive effect on the propensity to cause craving and relapse in both people and in rats, and that females trained to respond for cocaine may be more sensitive to this effect. Thus, the researchers tested whether reinstatement of alcohol responding was different in male and female rats in the presence of the alcohol-paired cue with or without an injection of a drug that increases stress. The drug used, yohimbine, also produces a stress response in humans, which assists in making comparisons across species.
The researchers found that overall, the female rats pressed more on the lever that previously led to alcohol access than the males following either cue or stress exposure alone. Strikingly, when the cues and stress were combined, females had an even greater increase in alcohol seeking behavior compared to males and when either stimulus was given alone.
The results indicate that females are more influenced by environmental cues and stress in promoting a "craving"-like response that can drive them to seek and consume alcohol. These findings provide the basis for dissecting the brain pathways that causes the interactions between cues, stress and sex in alcohol seeking and drinking behavior.
"Individuals attempting to maintain abstinence are exposed to a number of factors that elicit craving and can lead to an increased risk of relapse," said Bertholomey. "The next step for us will be to understand the mechanisms responsible for this enhanced sensitivity in females, which will direct further development of pharmacological and behavioral interventions that might reduce craving and prevent relapse."
Alcohol use disorders are diagnosed in approximately 17 million adults in the United States, representing 9.9 and 4.6 percent of men and women in that age group, respectively, according to the National Survey on Drug Use and Health (NSDUH). The Centers for Disease Control and Prevention report that alcohol-related problems cost the United States $223.5 billion and represent the third leading cause of preventable death.
http://www.sciencedaily.com/releases/2015/04/150401132854.htm
Prebiotics may help to cope with stress
Prebiotic fibers can help to protect beneficial gut bacteria and restore healthy sleep patterns after a stressful event
February 10, 2017
Science Daily/Frontiers
Probiotics are well known to benefit digestive health, but prebiotics are less well understood. Recent study in rats shows that prebiotic fibers may help to protect beneficial gut bacteria and restore healthy sleep patterns after a stressful event.
Probiotics are well known to benefit digestive health, but prebiotics are less well understood. Prebiotics are certain types of non-digestible fibers that probiotic bacteria feed on, such as the fibers found in many plant sources like asparagus, oatmeal, and legumes. Certain bacteria also feed on non-fibers such as the protein lactoferrin, which also acts like a prebiotic and is found in breast milk.
According to a new study published in the online journal, Frontiers in Behavioral Neuroscience by Professor Monika Fleshner, PhD, and her team from the University of Colorado, Boulder, regular intake of prebiotics may promote beneficial gut bacteria and recovery of normal sleep patterns after a stressful episode.
"Acute stress can disrupt the gut microbiome," explained Dr. Agnieszka Mika, a postdoctoral fellow and one of the authors of the study, "and we wanted to test if a diet rich in prebiotics would increase beneficial bacteria as well as protect gut microbes from stress-induced disruptions. We also wanted to look at the effects of prebiotics on the recovery of normal sleep patterns, since they tend to be disrupted after stressful events."
In this experiment, test rats received prebiotic diets for several weeks prior to a stressful test condition and compared with control rats that did not receive the prebiotic-enriched diet. Interestingly, rats that ate prebiotics prior to the stressful event did not experience stress-induced disruption in their gut microbiota, and also recovered healthier sleep patterns sooner than controls.
Given that these experiments were done in rats, are these results relevant for humans? "The stressor the rats received was the equivalent of a single intense acute stressful episode for humans, such as a car accident or the death of a loved one," said Dr. Robert S. Thompson, the lead author of the study. "A next set of studies will be looking exactly at that question -- can prebiotics help humans to protect and restore their gut microflora and recover normal sleep patterns after a traumatic event?"
In the mean time, should we start including prebiotics in our diets to help cope with stress? "So far no adverse effects from prebiotics have been reported," said Dr. Mika, "and they are found widely in many plants, even present in breast milk, and are already commercially available." Healthy gut bacteria and restful sleep could be your benefits.
https://www.sciencedaily.com/releases/2017/02/170210130951.htm
Stress May Delay Brain Development in Early Years
June 6, 2012
Science Daily/University of Wisconsin-Madison
Stress may affect brain development in children, altering growth of a specific piece of the brain and abilities associated with it, according to researchers at the University of Wisconsin-Madison.
"There has been a lot of work in animals linking both acute and chronic stress to changes in a part of the brain called the prefrontal cortex, which is involved in complex cognitive abilities like holding on to important information for quick recall and use," says Jamie Hanson, a UW-Madison psychology graduate student. "We have now found similar associations in humans, and found that more exposure to stress is related to more issues with certain kinds of cognitive processes."
Children who had experienced more intense and lasting stressful events in their lives posted lower scores on tests of what the researchers refer to as spatial working memory. They had more trouble navigating tests of short-term memory such as finding a token in a series of boxes, according to the study, which will be published in the June 6 issue of the Journal of Neuroscience.
Brain scans revealed that the anterior cingulate, a portion of the prefrontal cortex believed to play key roles in spatial working memory, takes up less space in children with greater exposure to very stressful situations.
"We're not trying to argue that stress permanently scars your brain. We don't know if and how it is that stress affects the brain," Hanson says. "We only have a snapshot -- one MRI scan of each subject -- and at this point we don't understand whether this is just a delay in development or a lasting difference. It could be that, because the brains is very plastic, very able to change, that children who have experienced a great deal of stress catch up in these areas."
The researchers determined stress levels through interviews with children ages 9 to 14 and their parents. The research team, which included UW-Madison psychology professors Richard Davidson and Seth Pollak and their labs, collected expansive biographies of stressful events from slight to severe.
"Instead of focusing in on one specific type of stress, we tried to look at a range of stressors," Hanson says. "We wanted to know as much as we could, and then use all this information to later to get an idea of how challenging and chronic and intense each experience was for the child."
Interestingly, there was little correlation between cumulative life stress and age. That is, children who had several more years of life in which to experience stressful episodes were no more likely than their younger peers to have accumulated a length stress resume. Puberty, on the other hand, typically went hand-in-hand with heavier doses of stress.
The researchers, whose work was funded by the National Institutes of Health, also took note of changes in brain tissue known as white matter and gray matter. In the important brain areas that varied in volume with stress, the white and gray matter volumes were lower in tandem.
White matter, Hanson explained, is like the long-distance wiring of the brain. It connects separated parts of the brain so that they can share information. Gray matter "does the math," Hanson says. "It takes care of the processing, using the information that gets shared along the white matter connections."
Gray matter early in development appears to enable flexibility; children can play and excel at many different activities. But as kids age and specialize, gray matter thins. It begins to be "pruned" after puberty, while the amount of white matter grows into adulthood.
"For both gray and white matter, we actually see smaller volumes associated with high stress," Hanson says. "Those kinds of effects across different kinds of tissue, those are the things we would like to study over longer periods of time. Understanding how these areas change can give you a better picture of whether this is just a delay in development or more lasting."
http://www.sciencedaily.com/releases/2012/06/120606164936.htm