New research suggests a period of rest following a traumatic event can help reduce the subsequent development of involuntary “memory intrusions,” a frequent symptom of post-traumatic stress disorder. Memory intrusions can be both visual or non-visual and are often referred to as flashbacks.
The study, published in Scientific Reports, discovered memory disturbances in PTSD may be mitigated by a process that occurs in the brain that can be facilitated by rest and sleep. Specifically, investigators discovered increased consolidation — storage and contextualization of memories in the brain — helps to alleviate memory intrusions. Experts believe this finding could shed new light on treatment and prevention.
Lead author Dr. Lone Hørlyck, from the Institute of Cognitive Neuroscience at University College London, said, “Over a lifetime, many people experience traumatic events, but most people do not develop persistent trauma symptoms.
“Identifying which mechanisms might contribute to memory intrusions in PTSD is important, as these disturbances comprise an important maintaining factor in the disorder.”
For the study, researchers presented 85 participants with emotionally negative videos, followed by either a period of wakeful rest or a simple control task, where participants were required to pay attention to numbers on a screen.
The videos comprised highly emotional content, such as badly injured people or serious accidents.
Researchers found that participants who had a period of rest following the viewing of negative videos reported fewer memory intrusions related to the videos over the following week.
In contrast, there was no difference between rest and the simple control task on a follow-up memory test assessing how much participants remembered when they wanted to.
Rest and certain phases of sleep are known to increase processing in the hippocampus, a key region of the brain that helps put memory in context.
According to the investigators, the results suggest that a strengthening of this contextual memory system is beneficial in preventing memory intrusions following trauma.
Senior author Professor Neil Burgess, of the Institute of Cognitive Neuroscience, said, “The coherence of memories is often compromised when people are exposed to psychological trauma, resulting in emotional memories popping up involuntarily and out of context.
“However, the binding of an event memory with its context may be partly restored with rest, facilitating deliberate control of the memory.
“The results show that specific brain systems could be targeted to reduce development of PTSD and may explain why treatments that focus on re-exposure and integrating the trauma with other information are beneficial.”
Hørlyck added, “Our findings contribute to a better understanding of the mechanisms that are at play when some people develop memory disturbances following trauma while others do not.”
Source: University College London/EurekAlert
Military veterans with post-traumatic stress disorder (PTSD) or concussion are much more likely to develop REM sleep behavior disorder (RBD) — a thrashing form of sleep behavior — compared to the general population, according to a new study published in the journal SLEEP.
Next, the researchers from the VA Portland Health Care System and Oregon Health & Science University (OHSU) want to investigate whether RBD might provide an early signal of neurodegenerative conditions such as Parkinson’s disease.
Typically, during REM (rapid eye movement) sleep, a person’s muscles are effectively paralyzed. In cases of RBD, however, the brain’s control of muscle paralysis is impaired, resulting in people acting out their dreams, sometimes causing injuries to themselves or their partners.
RBD is estimated to affect less than 1% of the general population. However, the researchers found that 9% of the 394 veterans in this study had RBD, and this number increased to 21% among those with PTSD.
“This is important because, in the general population, RBD has been linked to Parkinson’s disease, and RBD often precedes classic symptoms of Parkinson’s by years,” said senior author Miranda Lim, M.D., Ph.D., a staff physician at the VA and assistant professor of neurology, medicine and behavioral neuroscience in the OHSU School of Medicine.
“We don’t know whether veterans who have PTSD and higher rates of RBD will go on to develop Parkinson’s, but it is an important question we need to answer.”
Researchers suspect chronic stress on the brain may play a role in causing the sleep disorder in veterans with PTSD, as many veterans have been exposed to concussion which potentially accelerates neurodegenerative processes.
Each participant underwent an overnight sleep study at the VA Portland Health Care System between 2015 and 2017 to determine the presence of dream enactment during episodes of REM sleep. Muscle activity was monitored constantly during the 8 hours of the study in order to diagnose RBD. The findings show that participants with PTSD had over 2-fold increased odds of RBD compared to veterans without PTSD.
“RBD seems to be highly prevalent in veterans with a history of trauma,” said lead author Jonathan Elliott, Ph.D., a research physiologist at the Portland VA and assistant professor of neurology in the OHSU School of Medicine.
Doctors involved in the study, including co-authors Kristianna Weymann, Ph.D., R.N., a clinical assistant professor in the OHSU School of Nursing, and Dennis Pleshakov, a student at the OHSU School of Medicine, will continue to track research participants with RBD, looking for early signs of Parkinson’s or other neurodegenerative conditions.
Although there are several approaches to ease certain Parkinson’s symptoms, including tremor and fatigue, there is no definitive therapy to prevent the condition.
Clinical trials for promising therapies are usually conducted well after patients have been diagnosed with Parkinson’s, at a stage which may be too late to reverse the symptoms. Lim said that identifying patients with RBD presents an opportunity to identify people earlier in the disease course, and potentially provides a more viable window to test promising interventions.
“By the time a patient shows classic symptoms of Parkinson’s, it may be too late,” Lim said. “If you could intervene when people first start to show RBD, maybe you could prevent later symptoms of Parkinson’s.”
Source: Oregon Health & Science University
Insomnia is a risk factor for suicide, and specifically treating severe insomnia in suicidal patients may help reduce suicidal thoughts, according to a new study published in the American Journal of Psychiatry.
“If you have a patient who complains that their sleep has taken a turn for the worse then there is reason to open the door to a question about suicide,” said Dr. Vaughn McCall, chair of the Department of Psychiatry and Health Behavior at the Medical College of Georgia (MCG) at Augusta University.
“If your patient says their sleep problem is really bad and they have had thoughts of killing themselves, maybe they should have a targeted treatment for their insomnia,” said McCall, corresponding author of the study and an expert on the triple threat of insomnia, depression and suicide.
More than 30 studies have linked insomnia to suicidal thoughts or actions, however suicide risk and prevention are largely overlooked in the treatment of insomnia, McCall said.
He is hoping the REST-IT — Reducing Suicidal Ideation Through Insomnia Treatment — study, the first clinical trial to investigate whether targeted insomnia treatment reduces suicide risk, will help change that.
“While the results do not argue for the routine prescription of hypnotics for mitigating suicidal ideation in all depressed outpatients with insomnia, they suggest that co-prescription of a hypnotic during initiation of an antidepressant may be beneficial in suicidal outpatients, especially in patients with severe insomnia,” the researchers write.
The study at MCG, Duke University and the University of Wisconsin involved 103 participants ages 18 to 65 with major depressive disorder, insomnia and suicidal thoughts.
In total, 30% of the participants had a prior suicide attempt; individuals with an active and imminent plan to commit suicide were excluded out of concern for their safety since it was an outpatient study, McCall says.
All participants took an antidepressant for the eight-week duration of the trial and half also took the sedative-hypnotic zolpidem at bedtime.
During the study, participants filled out regular self-reports of their insomnia severity and completed a daily sleep diary that included details like how many times they woke up during the night and how long they actually slept.
The researchers also analyzed distorted thoughts about sleep, like participants thinking they would never again have a good night’s sleep, something McCall has previously shown is itself a risk factor for suicide. The frequency and intensity of disturbing dreams or nightmares, also a factor in insomnia-related suicide, were measured.
Patients wore a wrist device to track their rest/activity cycles. Depression severity was measured by psychiatry staff at each study visit, and participants also completed the Beck Hopelessness Scale, which measures pessimism and negative expectations and is considered a predictor of suicidal behavior.
Those taking the sleep aid showed both significant immediate and longer-term improvement in their reported insomnia severity. While both groups reported significant improvement in their feelings about hopelessness, quality of life, nightmares and dysfunctional beliefs about sleep, as well as related insomnia and suicidality, the group taking the sleep aid had a greater reduction in suicidal thinking.
The sleep aid was most effective in reducing suicidal thoughts in patients with the most severe insomnia. There were no deaths or suicide attempts by participants during the course of the study.
The researchers note the safety of using narcotics in patients with suicidal thoughts and the fact that participants largely followed study protocols very well also were important findings. Both lay the groundwork for doing additional outpatient trials for patients with suicidal thoughts, McCall said.
Hypnotics, like the drug they used for the study, are a common means to commit suicide, and there are also concerns about becoming dependent on them.
To address these concerns, participants only received a week’s supply of the sleep aid until their suicidal thoughts began to abate, and the sleep aid was stopped after eight weeks. Afterward their condition remained the same or continued to improve, McCall said. Eight weeks is the timeframe McCall uses in prescribing the drug in his practice.
Two weeks after the study concluded both study groups — including those not taking the sleep aid — appeared to have maintained progress with reduced depression scores and suicidal thoughts. A possible reason all participants benefited could be the extra attention they received over the course of the study, McCall noted.
Insomnia dramatically increases the risk of depression and vice versa and both increase suicide risk, McCall said. Depression studies often exclude those with strong suicidality, he said. Now he wants to understand more about why insomnia is a risk for suicide and how treating it reduces that risk.
Source: Medical College of Georgia at Augusta University
A new study suggests that women who experience night sweats are more vulnerable to cognitive dysfunction as their sleep duration increases.
Previous studies have shown a link between daytime hot flashes and worse memory performance.
In this new study involving women with a history of breast cancer, however, researchers focused on night sweats and how they relate to total sleep time. Surprisingly, more frequent night sweats were associated with greater sleep duration, according to the researchers.
Even more surprising, they said, was the finding that these same women experiencing night sweats became more vulnerable to prefrontal cortex deficits, including decreased attention and executive function, as their sleep duration increased.
Total sleep time, however, was unrelated to memory performance, they noted.
The researchers also discovered that daytime hot flashes had no impact on total sleep time.
“This work presents novel insights into the influence of menopause symptoms on cognitive performance among women with a history of breast cancer and raises the possibility that hot flash treatments could benefit cognition in these women through effects on sleep,” said lead author John Bark, doctoral student in behavioral neuroscience the University of Illinois at Chicago.
“Studies like this are valuable in helping health care providers develop effective treatment options for menopausal women complaining of cognitive decline as they focus on modifiable risk factors,” added Dr. Stephanie Faubion, medical director for The North American Menopause Society.
The study findings were presented during 2019 North American Menopause Society (NAMS) annual meeting.
Source: The North American Menopause Society
MIT researchers have discovered a strong relationship between students’ grades and how much sleep they get. Furthermore, the time a student goes to bed and the consistency of their sleep habits also make a big difference.
Interestingly, getting a good night’s sleep just before a big test is not good enough — it takes several nights in a row of good sleep to make a difference.
MIT researchers studied 100 students in an engineering class. The students were given Fitbits to track their activity over the course of a semester. The findings — some unsurprising, but some quite unexpected — appear in the journal Science of Learning.
The research was performed by MIT postdoc Dr. Kana Okano, professors Jeffrey Grossman and John Gabrieli, and two others.
One of the surprises was that individuals who went to bed after some particular threshold time — for these students, that tended to be 2 a.m., but it varied from one person to another — tended to perform less well on their tests no matter how much total sleep they ended up getting.
Uniquely, the study did not begin as research on sleep. Instead, Grossman was trying to find a correlation between physical exercise and the academic performance of students in his class Introduction to Solid-State Chemistry. In addition to having 100 of the students wear Fitbits for the semester, he also enrolled about one-fourth of them in an intense fitness class created specifically for this study.
The thinking was that there might be measurable differences in test performance between the two groups. There wasn’t. Those without the fitness classes performed just as well as those who did take them.
“What we found at the end of the day was zero correlation with fitness, which I must say was disappointing since I believed, and still believe, there is a tremendous positive impact of exercise on cognitive performance,” Grossman said.
He speculates that the intervals between the fitness program and the classes may have been too long to show an effect. But meanwhile, in the vast amount of data collected during the semester, some other correlations did become obvious.
While the devices weren’t explicitly monitoring sleep, the Fitbit program’s proprietary algorithms did detect periods of sleep and changes in sleep quality, primarily based on lack of activity.
These correlations were not at all subtle, Grossman said. There was essentially a straight-line relationship between the average amount of sleep a student got and their grades on the 11 quizzes, three midterms, and final exam, with the grades ranging from A’s to C’s.
“There’s lots of scatter, it’s a noisy plot, but it’s a straight line,” he said. The fact that there was a correlation between sleep and performance wasn’t surprising, but the extent of it was, he said. Of course, this correlation can’t absolutely prove that sleep was the determining factor in the students’ performance, as opposed to some other influence that might have affected both sleep and grades. But the results are a strong indication, Grossman said, that sleep “really, really matters.”
“Of course, we knew already that more sleep would be beneficial to classroom performance, from a number of previous studies that relied on subjective measures like self-report surveys,” Grossman said. “But in this study the benefits of sleep are correlated to performance in the context of a real-life college course, and driven by large amounts of objective data collection.”
The study also revealed no improvement in scores for those who made sure to get a good night’s sleep right before a big test.
According to the data, “the night before doesn’t matter,” Grossman said. “We’ve heard the phrase ‘Get a good night’s sleep, you’ve got a big day tomorrow.’ It turns out this does not correlate at all with test performance. Instead, it’s the sleep you get during the days when learning is happening that matter most.”
Another surprising finding is that there appears to be a certain cutoff for bedtimes, such that going to bed later results in poorer performance, even if the total amount of sleep is the same.
“When you go to bed matters,” Grossman said. “If you get a certain amount of sleep — let’s say seven hours — no matter when you get that sleep, as long as it’s before certain times, say you go to bed at 10, or at 12, or at 1, your performance is the same. But if you go to bed after 2, your performance starts to go down even if you get the same seven hours. So, quantity isn’t everything.”
Quality of sleep also mattered, not just quantity. For example, those who got relatively consistent amounts of sleep each night did better than those who had greater variations from one night to the next, even if they ended up with the same average amount.
This research also helped to provide an explanation for something that Grossman says he had noticed and wondered about for years, which is that on average, the women in his class have consistently gotten better grades than the men.
Now, he has a possible answer: The data show that the differences in quantity and quality of sleep can fully account for the differences in grades. “If we correct for sleep, men and women do the same in class. So sleep could be the explanation for the gender difference in our class,” he said.
More research will be needed to understand the reasons why women tend to have better sleep habits than men. “There are so many factors out there that it could be,” Grossman said. “I can envision a lot of exciting follow-on studies to try to understand this result more deeply.”
A new circadian rhythm intervention designed by researchers from Stanford University School of Medicine helped teens get 43 more minutes of sleep per night.
The treatment had two components: brief, early morning flashes of bright, broad-spectrum white light to reset the teens’ circadian clocks, and cognitive behavioral therapy (CBT) that motivated them to try earlier bedtimes.
The findings are published in JAMA Network Open.
“Using a passive light therapy during sleep, we can help teens get an extra 43 minutes of sleep every single night,” said senior author Jamie Zeitzer, Ph.D., associate professor of psychiatry and behavioral sciences.
The light was delivered by a device in the teens’ bedrooms that was programmed to give off 3-millisecond flashes of light every 20 seconds during the last few hours of sleep.
The brief flashes of light did not wake the teens. Zeitzer’s previous research on jet lag had shown that exposure to short flashes of light can trick the brain into adjusting to a new time zone, even during sleep.
Chronic sleep deprivation is common in teenagers, Zeitzer said. The body’s circadian clock, which controls daily rhythms of when we sleep and when we’re awake, is naturally set later in teens than in children or in adults, meaning that teens often don’t feel sleepy until late at night.
Teens might also stay up late because of such social influences as homework and electronic device use. Early school start times often require them to wake up before they’re fully rested, further contributing to sleep deprivation.
Previous research looked at whether cognitive behavioral therapy alone could help teens go to sleep earlier. Success was modest: After the treatments, teens went to sleep 10 to 15 minutes sooner, on average. But these interventions might have put participants at odds with their own body clocks, asking them to try to fall asleep before they were tired, a behavior that is difficult to sustain, Zeitzer said.
“We have a biological drive to stay awake in the hours before we normally go to sleep,” he said. “So our team wondered if we could adjust the circadian timing, having the teens essentially move their brains to Denver while they’re living in California.”
In the first four-week segment of the study, researchers tested light therapy alone in a group of 72 teenagers. For four weeks, half of the participants were exposed to the frequent brief light flashes during the final three hours of their normal sleep period. The rest of the teens received a sham light treatment, involving three bright flashes of light per hour — too little to reset their body clocks.
Although the light therapy caused the teens who were exposed to it to feel more tired earlier at night, they still stayed up late. Using the light alone was not enough to increase the amount of time they slept.
“We had to convince teens to try to go to sleep earlier,” Zeitzer said.
So, in the second four-week phase of the study, the team recruited 30 teens; half of them received light therapy during their final two hours of sleep, and half had sham light therapy.
This time, however, all of the teens also received four one-hour sessions of CBT to encourage them to go to bed earlier. Therapists worked with each participant to identify areas of their lives they cared about that would be better if they had more sleep — such as academics, physical appearance or athletic performance —and used these to help motivate the teens.
The CBT also included giving them information about the body clock, sleep hygiene and strategies for waking up earlier on weekends.
In addition to the extra sleep, participants who received both light therapy and CBT went to bed an average of 50 minutes earlier than participants who only received CBT. In addition, the participants receiving both therapies were six times more successful than those receiving only CBT at maintaining consistent bedtimes.
Earlier studies of light therapy for resetting the circadian clock have shown that the early morning flashes of light must continue daily to be effective, Zeitzer said.
“The cool part, for an intervention teens would potentially have to live with for years, is that it is completely passive. We set up the flashing light in the person’s bedroom and put it on a timer; they don’t have to wear a device, remember to turn it on, or do anything else.”
The flashing light used in th7e study was a programmable bridge beacon; it is not marketed as a sleep aid, Zeitzer said.
The next step, he said, is to determine the best way to deliver brief CBT for improving sleep duration to large numbers of people.
Source: Stanford Medicine