PTSD and poor sleep

A study claims that poor sleep in people with PTSD could lead to a decrease in physical activity and an increase in obesity.

Poor sleep quality may lower physical activity in people with post-traumatic stress disorder, according to a recent study.

Researchers found that PTSD was independently associated with worse sleep quality at baseline, and participants with current PTSD at baseline had lower physical activity one year later.

Further analysis found that sleep quality completely mediated the relationship between baseline PTSD status and physical activity at the one-year follow-up, suggesting that the association of reduced sleep quality with reduced physical activity could comprise a behavioral link to negative health outcomes such as obesity.

"We found that sleep quality was more strongly associated with physical activity one year later than was having a diagnosis of PTSD," Lisa Talbot, lead author of the study and postdoctoral fellow at the San Francisco VA Medical Center and the University of California- San Francisco, said in a statement. "The longitudinal aspect of this study suggests that sleep may influence physical activity."

For the study, researchers collected and analyzed data from  the Mind Your Heart Study, a prospective cohort study of 736 outpatients recruited from two Department of Veterans Affairs (VA) medical centers. PTSD was assessed with the Clinician-Administered PTSD Scale (CAPS).  At baseline participants rated their sleep quality overall during the last month, and at baseline and again one year later they reported how physically active they have been during the last month. Of the 736 military veteran participants, 258 had current or subsyndromal PTSD.

Researchers said the results suggest that behavioral interventions to increase physical activity should include an assessment for sleep disturbance.

"The findings also tentatively raise the possibility that sleep problems could affect individuals' willingness or ability to implement physical activity behavioral interventions," Talbout said. "Sleep improvements might encourage exercise participation."

The findings were recently published in the  Journal of Clinical Sleep Medicine, which is published by the American Academy of Sleep Medicine.

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Study: Exercise improves brain activity and memory in adults

A study claims that aerobic exercise has many benefits for adults including improved brain activity and memory in addition to physical fitness.

A new study conducted by researchers at the Center for BrainHealth at The University of Texas at Dallas published online in the open-access journal Frontiers in Aging Neuroscience found that engaging in a physical exercise regimen helps healthy aging adults improve their memory, brain health and physical fitness. This finding is significant considering that among adults 50 and older, "staying mentally sharp" outranks social security and physical health as the top priority and concern in the United States.

"Science has shown that aging decreases mental efficiency and memory decline is the number one cognitive complaint of older adults," said Sandra Bond Chapman, Ph.D., founder and chief director of the Center for BrainHealth, Dee Wyly Distinguished University Chair and lead author of the paper. "This research shows the tremendous benefit of aerobic exercise on a person's memory and demonstrates that aerobic exercise can reduce both the biological and cognitive consequences of aging."

For the study, sedentary adults ages 57-75 were randomized into a physical training or a wait-list control group. The physical training group participated in supervised aerobic exercise on a stationary bike or treadmill for one hour, three times a week for 12 weeks. Participants' cognition, resting cerebral blood flow, and cardiovascular fitness were assessed at three time points: before beginning the physical exercise regimen, mid-way through at 6 weeks, and post-training at 12 weeks.

"By measuring brain blood flow non-invasively using arterial spin labeling (ASL) MRI, we can now begin to detect brain changes much earlier than before," said Sina Aslan, Ph.D., founder and president of Advance MRI and collaborator on the study. "One key region where we saw increase in brain blood flow was the anterior cingulate, indicating higher neuronal activity and metabolic rate. The anterior cingulate has been linked to superior cognition in late life."

Exercisers who improved their memory performance also showed greater increase in brain blood flow to the hippocampus, the key brain region affected by Alzheimer's disease. Chapman pointed out that, using noninvasive brain imaging techniques, brain changes were identified earlier than memory improvements, implicating brain blood flow as a promising and sensitive metric of brain health gains across treatment regimens.

"Physical exercise may be one of the most beneficial and cost-effective therapies widely available to everyone to elevate memory performance," Chapman said. "These findings should motivate adults of all ages to start exercising aerobically."

Chapman cautioned that while physical exercise is associated with a selective or regional brain blood flow, it did not produce a change in global brain blood flow.

"In another recent study, we have shown that complex mental training increases whole brain blood flow as well as regional brain blood flow across key brain networks," Chapman said. "The combination of physical and mental exercise may be the best health measures to improve overall cognitive brain health. We have just begun to test the upper boundaries of how we can enhance our brain's performance into late life. To think we can alter and improve the basic structure of the mature brain through aerobic exercise and complex thinking should inspire us to challenge our thinking and get moving at any age."

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Social status can change brain activity

A person's social status can alter their brain activity as well as their physical and mental health.

 New studies released today reveal links between social status and specific brain structures and activity, particularly in the context of social stress. The findings were presented at Neuroscience 2013, the annual meeting of the Society for Neuroscience and the world's largest source of emerging news about brain science and health.

Using human and animal models, these studies may help explain why position in social hierarchies strongly influences decision-making, motivation, and altruism, as well as physical and mental health. Understanding social decision-making and social ladders may also aid strategies to enhance cooperation and could be applied to everyday situations from the classroom to the boardroom.

Today's new findings show that:

• Adult rats living in disrupted environments produce fewer new brain cells than rats in stable societies, supporting theories that unstable conditions impair mental health and cognition
• People who have many friends have certain brain regions that are bigger and better connected than those with fewer friends. It's unknown whether their brains were predisposed to social engagement or whether larger social networks prompted brain development
• In situations where monkeys can potentially cooperate to improve their mutual reward, certain groups of brain cells work to accurately predict the responses of other monkeys
• Following extreme social stress, enhancing brain changes associated with depression can have an anti-depressant effect in mice

Other recent findings discussed show that:

• Defeats heighten sensitivity to social hierarchies and may exacerbate brain activity related to social anxiety

"Social subordination and social instability have been associated with an increased incidence of mental illness in humans," said press conference moderator Larry Young, PhD, of Emory University, an expert in brain functions involved with social behavior. "We now have a better picture of how these situations impact the brain. While this information could lead to new treatments, it also calls on us to evaluate how we construct social hierarchies -- whether in the workplace or school -- and their impacts on human well-being."

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