Different types of memory and epilepsy

This article discusses different types of brainwaves, and how they relate to epilepsy.

Our long-term memory is consolidated when we sleep. Short-term memory traces in the hippocampus, an area deep in the brain, are then relocated to more outer parts of the brain. An international team of neuroscientists, among who Mathilde Bonnefond and Til Ole Bergmann from the Donders Institute at Radboud Universiy, now shows how a three-step brain oscillation plays an important part in that process. Nature Neurosciences publishes the results on September 21st.

Bonnefond and Bergmann specialize in research on oscillations: waves of brain activity. 'Non-rapid eye movement (NREM) sleep is responsible for the memory consolidation during our sleep', Bonnefond explains. 'NREM is known for its very slow oscillations (SOs). Other types of oscillations are hidden inside these SOs. We discovered that three types of oscillations are nested inside each other in the hippocampus and have a joint function.'

Slow waves, spindles and ripples

Slow oscillations only happen about once per second (~0.75 Hz). In a specific time frame within these SOs, Bergmann, Bonnefond and their colleagues found clusters of oscillations of an intermediate speed: the so called spindles which happen about 15 times per second (12 -- 16 Hz). And within these spindles, they found clusters of superfast oscillations called ripples, which happen about 90 times per second (80 -- 100 Hz), and which reflect the local reactivation of the memory trace to be shuttled to the cortex.

To summarize: SOs contain spindles, which in their turn contain ripples. 'Earlier studies only coupled these oscillation types in pairs', Bonnefond explains. 'But now, we see that SOs, spindles and ripples are functionally coupled in the hippocampus. And we hypothesize that they provide fine-tuned temporal frames for the transfer of memory traces to the neocortex.'

Epilepsy

The group of researchers investigated the process in human epilepsy patients during natural sleep. Doctors were looking for the brain areas responsible for their epilepsy, and the current research was done at the same time: with special electrodes, the researchers recorded oscillations from inside the brain. Bonnefond: 'This was a great opportunity to investigate the hippocampus, since it's difficult to measure deep brain regions with classical electrophysiological techniques.'

The patients did not have to remember any specific information. 'You're consolidating memories every night, so we investigated the process in general. The next step would be to link these clustered oscillations to specific memories.'

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Study: Sleep makes memories more accessible

A study shows that sleep makes memories more accessible.

Sleeping not only protects memories from being forgotten, it also makes them easier to access, according to new research from the University of Exeter and the Basque Centre for Cognition, Brain and Language. The findings suggest that after sleep we are more likely to recall facts which we could not remember while still awake.

In two situations where subjects forgot information over the course of 12 hours of wakefulness, a night's sleep was shown to promote access to memory traces that had initially been too weak to be retrieved.

The research, published in the journal Cortex, tracked memories for novel, made-up words learnt either prior to a night's sleep, or an equivalent period of wakefulness. Subjects were asked to recall words immediately after exposure, and then again after the period of sleep or wakefulness.

The key distinction was between those word memories which participants could remember at both the immediate test and the 12-hour retest, and those not remembered at test, but eventually remembered at retest.

The researcher found that, compared to daytime wakefulness, sleep helped rescue unrecalled memories more than it prevented memory loss.

Nicolas Dumay of the University of Exeter explains: "Sleep almost doubles our chances of remembering previously unrecalled material. The post-sleep boost in memory accessibility may indicate that some memories are sharpened overnight. This supports the notion that, while asleep, we actively rehearse information flagged as important. More research is needed into the functional significance of this rehearsal and whether, for instance, it allows memories to be accessible in a wider range of contexts, hence making them more useful."

The beneficial impact of sleep on memory is well established, and the act of sleeping is known to help us remember the things that we did, or heard, the previous day. The idea that memories could also be sharpened and made more vivid and accessible overnight, however, is yet to be fully explored.

Dr Dumay believes the memory boost comes from the hippocampus, an inner structure of the temporal lobe, unzipping recently encoded episodes and replaying them to regions of the brain originally involved in their capture -- this would lead the subject to effectively re-experience the major events of the day.

Nicolas Dumay is an experimental psychologist at the University of Exeter and an honorary Staff Scientist at the Basque Centre for Cognition, Brain and Language (BCBL), in Spain.

'Sleep not just protects memories against forgetting, it also makes them more accessible' is published in the journal Cortex.

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Study: Why students shouldn't stay up all night

This study explains why students should not pull all-nighters to study.

Memory neurons lull us to sleep in order to consolidate what we've learned, say researchers from Brandeis University, who advise students against pulling all-nighters to prepare for tests.

Knowing that sleep, memory and learning are deeply intertwined, the Brandeis team set out to find out whether memory is consolidated during sleep simply because the brain happens to be at rest or whether those neurons provoke sleep in order to do their job.

In the study, which was published in the journal eLife, the researchers focused on a specific group of neurons called the dorsal paired medial (DPM), which are well known to implant memories in fruit flies.

In what's thought to be a first-of-its-kind observation, the flies slept more when the DPM neurons were activated, yet continued to buzz about when these neurons were switched off.

As these neurons start to convert short-term memory to long-term memory, they do their best to make sure you stay sleeping and actually hinder wakefulness, according to the study.

In the case of the fruit flies, the part of their brain in charge of memory and learning — called the mushroom body — The is also what determines wakefulness and, consequently, it's where the DPM are housed.

"It's almost as if that section of the mushroom body were saying 'hey, stay awake and learn this,'" says co-author Bethany Christmann, a graduate student at Brandeis. "Then, after a while, the DPM neurons start signaling to suppress that section, as if to say 'you're going to need sleep if you want to remember this later.'"

Christmann points out that knowing how sleep, memory and learning work together in the fruit fly brain can help researchers know what to look for when working with human participants.

"Eventually, it could help us figure out how sleep or memory is affected when things go wrong, as in the case of insomnia or memory disorders," she says.

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Study: Losing sleep can hurt your memory

A study shows that losing sleep can hurt a person's memory.

Lack of sleep, already considered a public health epidemic, can also lead to errors in memory, finds a new study by researchers at Michigan State University and the University of California, Irvine.

The study, published online in the journalPsychological Science, found participants deprived of a night's sleep were more likely to flub the details of a simulated burglary they were shown in a series of images.

Distorted memory can have serious consequences in areas such as criminal justice, where eyewitness misidentifications are thought to be the leading cause of wrongful convictions in the United States.

"We found memory distortion is greater after sleep deprivation," said Kimberly Fenn, MSU associate professor of psychology and co-investigator on the study. "And people are getting less sleep each night than they ever have."

The Centers for Disease Control and Prevention calls insufficient sleep an epidemic and said it's linked to vehicle crashes, industrial disasters and chronic diseases such as hypertension and diabetes.

The researchers conducted experiments at MSU and UC-Irvine to gauge the effect of insufficient sleep on memory. The results: Participants who were kept awake for 24 hours -- and even those who got five or fewer hours of sleep -- were more likely to mix up event details than participants who were well rested.

"People who repeatedly get low amounts of sleep every night could be more prone in the long run to develop these forms of memory distortion," Fenn said. "It's not just a full night of sleep deprivation that puts them at risk."

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Brain damage can occur even in mild brain injuries

A study shows that even a mild brain injury can cause lasting brain damage.

Even mild traumatic brain injury may cause brain damage and thinking and memory problems, according to a study published in the July 16, 2014, online issue of Neurology®, the medical journal of the American Academy of Neurology.

For the study, 44 people with a mild traumatic brain injury and nine people with a moderate traumatic brain injury were compared to 33 people with no brain injury. All of the participants took tests of their thinking and memory skills. At the same time, they had diffusion tensor imaging scans, a type of MRI scan that is more sensitive than traditional MRI for detecting damage to brain cells and helps map fiber tracts that connect brain regions. The people with brain injuries had their scans an average of six days after the injury. A year later, 23 of those with injuries had another scan and took the cognitive tests again.

Compared to the people with no brain injury, those with injuries had brain damage in brain white matter consisting of disruption to nerve axons, those parts of nerve cells that make up white matter and that allow brain cells to transmit messages to each other.

The study found that patient scores on the verbal letter fluency task, a test of thinking and memory skills, were 25 percent lower than in the healthy people. This was strongly related to the imaging measures of white matter damage.

“Most of the studies thus far have focused on people with severe and chronic traumatic brain injury,” said study author Andrew Blamire, PhD, of Newcastle University in the United Kingdom. “We studied patients who had suffered clinically mild injuries often from common accidents such as falling from a bicycle, or slow speed car accidents. This finding is especially important, as 90 percent of all traumatic brain injuries are mild to moderate.”

One year after the injury, the scores on thinking and memory tests were the same for people with brain injuries and those with no injuries, but there were still areas of brain damage in people with injuries. “These results show that thinking skills were recovering over time,” Blamire said. “The areas of brain damage were not as widespread across the brain as previously, but focused in certain areas of the brain, which could indicate that the brain was compensating for the injuries.”

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Too much and too little sleep indicate memory problems

This article claims that both too much and too little sleep can lead to memory problems in older women.

Seniors who slept too little or too much during midlife or after are at increased risk for memory problems, as are those whose sleep habits changed over time, a new study suggests.

Researchers looked at more than 15,000 women, 70 and older, who took part in a large study of health professionals. The women were depression- and stroke-free when they underwent their initial assessment.

Participants who slept five hours or less, or nine hours or more a day -- either in midlife or later life -- had worse memory than those who slept seven hours a day. The difference in memory was equivalent to nearly two extra years of age, the researchers said.

Women whose amount of sleep changed by more than two hours a night over time had poorer memory than those who had no sleep changes, according to the study published May 1 in the Journal of the American Geriatrics Society.

"Given the importance of preserving memory into later life, it is critical to identify modifiable factors, such as sleeping habits, that may help achieve this goal," study leader Elizabeth Devore, of Brigham and Women's Hospital in Boston, said in a hospital news release.

"Our findings suggest that getting an 'average' amount of sleep, seven hours per day, may help maintain memory in later life and that clinical interventions based on sleep therapy should be examined for the prevention of [mental] impairment," she added.

The study adds "to our knowledge about how sleep impacts memory. More research is needed to confirm these findings and explore possible mechanisms underlying these associations," Devore concluded.

While the study found an association between sleep time during midlife and older age and memory function in older women, it did not prove a cause-and-effect relationship.

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Sleep necessary for mental health and well-being

This article discusses how crucial good sleep is for a person's mental health and well-being, and the consequences of not having good quality sleep.

Having a good quality and restorative sleep is essential for one to be able to function well throughout the day. Failure to do so will lead to numerous impacts to health, both long- and short-term.

According to the Sleep Disorder Society Malaysia (SDSM) president Dr Muhammad Muhsin Ahmad Zahari, some of the short-term negative impacts include short attention span, memory recall and learning; while its long-term effects have long been associated with hypertension, ischaemic heart disease, stroke, obesity, diabetes, weakened immune system, and cancer.

Dr Muhammad Muhsin added that sleep disorder can also increase the risk of accidents.

"People who suffer from insomnia are seven times more likely to become involved in an accident which then resulted in death or serious injury," he said at the launch of the `World Sleep Day Celebration and Sleep 2014 Conference' at Cititel Hotel, here, today.

He revealed that sleep disorder actually constitute a global epidemic that threatens health and quality of life for up to 45% of the world's population, thus it is essential for everyone to have a better understanding of sleep conditions.

"Sleep is a basic human need and it is crucial not only to our health and well-being, it also plays an important role in the metabolic regulation in children," said Dr Muhammad adding that SDSM is working closely with the relevant authorities, associations and organisations in improving the quality of service of sleep medicine.

"With regards to the quality service in sleep medicine, facilities such as sleep laboratory are vital. As our population grows, there is definitely a need to increase the number of sleep laboratory in public hospitals to cater to the need of the people." he added.

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Study: Concussions and Alzheimer's are linked

According to a new study, older adults with memory issues and Alzheimer's disease also generally have a history of concussion.

Older adults with memory problems and a history of concussion have more buildup of Alzheimer's disease-associated plaques in the brain than those who also had concussions but don't have memory problems, according to a new study.

''What we think it suggests is, head trauma is associated with Alzheimer's-type dementia -- it's a risk factor," said study researcher Michelle Mielke, an associate professor of epidemiology and neurology at Mayo Clinic Rochester. "But it doesn't mean someone with head trauma is [automatically] going to develop Alzheimer's."

Her study is published online Dec. 26 and in the Jan. 7 print issue of the journal Neurology.

Previous studies looking at whether head trauma is a risk factor for Alzheimer's have come up with conflicting results, she noted. And Mielke stressed that she has found only a link or association, not a cause-and-effect relationship.

In the study, Mielke and her team evaluated 448 residents of Olmsted County, Minn., who had no signs of memory problems. They also evaluated another 141 residents with memory and thinking problems known as mild cognitive impairment.

More than 5 million Americans have Alzheimer's disease, according to the Alzheimer's Association. Plaques are deposits of a protein fragment known as beta-amyloid that can build up in between the brain's nerve cells. While most people develop some with age, those who develop Alzheimer's generally get many more, according to the Alzheimer's Association. They also tend to get them in a predictable pattern, starting in brain areas crucial for memory.

In the Mayo study, all participants were aged 70 or older. The participants reported if they ever had a brain injury that involved loss of consciousness or memory.

Of the 448 without any memory problems, 17 percent had reported a brain injury. Of the 141 with memory problems, 18 percent did. This suggests that the link between head trauma and the plaques is complex, Mielke said, as the proportion of people reporting concussion was the same in both groups.

Brain scans were done on all the participants. Those who had both concussion history and cognitive [mental] impairment had levels of amyloid plaques that were 18 percent higher than those with cognitive impairment but no head trauma history, the investigators found.

Among those with mild cognitive impairment, those with concussion histories had a nearly five times higher risk of elevated plaque levels than those without a history of concussion.

The researchers don't know why some with concussion history develop memory problems and others do not.

The research was funded by the U.S. National Institutes of Health, among several other supporters.

The study adds valuable information for experts in the field, said Dr. Robert Glatter, director of sports medicine and traumatic brain injury in the department of emergency medicine at Lenox Hill Hospital, in New York City. Glatter, who is also a former sideline physician for the National Football League's New York Jets, reviewed the new study findings.

Other studies, he said, often rely on postmortem information. In the Mayo study, participants had to have loss of consciousness as a measure of having a concussion history, Glatter noted. However, he added, the new thinking is that loss of consciousness is not necessary to define a concussion -- one can occur without that.

The effect of head injury may be cumulative over time in the development of Alzheimer's, he said. In the past, experts thought only severe head trauma was linked with Alzheimer's, but less severe injury may actually be relevant as well, he added.

Some other factor or factors yet to be discovered may be at play, Glatter said.

Both Mielke and Glatter stressed that concussions don't automatically lead to Alzheimer's. "Not all people with head trauma develop Alzheimer's," Glatter said.

"If you do hit your head, it doesn't mean you are going to develop Alzheimer's," Mielke said, although "it may increase your risk."

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Study: Brain damage from concussion stays after symptoms subside

A study shows that after symptoms from a concussion go away, the brain damage from the concussion persists.

Months after concussion symptoms such as dizziness, headaches and memory loss fade, the brain continues to show signs of injury, a new study suggests.

Comparing 50 concussion patients with the same number of healthy people, researchers found that the brains of those suffering concussions showed abnormalities four months later. This happened despite the fact that their symptoms had already eased to some degree.

The findings may sway conventional thinking about when it's safe to resume physical activities that could produce another concussion, the study authors said.

"This is a very different population than professional athletes going out and having concussions on a fairly [frequent] basis, as well as jostling their brain around their skull on a regular basis in practice," said study author Andrew Mayer, an associate professor of translational neuroscience at the Mind Research Network in Albuquerque, N.M. It's hard to predict an outcome based on these findings, he said, "but just because you feel you're healed doesn't mean you are."

The study, which was funded by the U.S. National Institutes of Health, is published in the Nov. 20 online edition of the journal Neurology.

Considered a mild traumatic brain injury that occurs from a sudden blow to the head or body, a concussion has symptoms that range from headache and blurry vision to difficulties in sleeping or thinking clearly. Most occur without losing consciousness, according to the U.S. Centers for Disease Control and Prevention.

Mayer and his team matched 50 patients with mild concussions to 50 healthy people of similar age and education levels. They tested all participants in memory and thinking skills, as well as other symptoms such as anxiety and depression.

Special brain scans using technology that is not available in standard brain scans were also given. All tests and scans were repeated two weeks after the concussion, and again four months later.

While concussion symptoms were reduced by up to 27 percent four months after injury, brain scans of those with concussions showed abnormalities in the frontal cortex area of both sides of the brain. These abnormalities may have resulted from changes in location of fluid around brain cells or changes in the shape of certain brain cells in response to damage, Mayer explained.

The findings, he noted, suggest that the recommendation that athletes suffering concussions should refrain from play for one to two weeks may not be sufficient.

"In one or two weeks, most people typically report feeling better," he said. "But when we start talking about it in an analogy of a burn or knee injury, it becomes a little more clear when the doctor says we need to wait a bit longer [to return to prior activities]. It makes sense that the brain would be similar to those tissue types," added Mayer.

Kenneth Podell, co-director of the Houston Methodist Concussion Center, said the study strengthens the understanding that physical changes within the brain after concussion are separate from mental symptoms. But Podell, who was not involved in the research, added that the study couldn't offer implications for potential long-term concussion effects such as depression or dementia.

"Everyone seen at four months should be followed in another four, six or eight months and then re-scanned," he said. "One of the biggest problems we have looking at concussions is we try to predict long-term effects from short-term findings. This injury is very difficult to commit the type of resources needed to do that kind of very expensive and time-consuming study."

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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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Children May Need Gradual Transition Back to Academics After Concussion

The American Academy of Pediatrics claims that once a child has a concussion, he or she may need a gradual transition back to school and academic classes.

This article is helpful in that it details accommodations.

I have some trouble with the assertions about rest. JR

A concussion should not only take a student athlete off the playing field -- it may also require a break from the classroom, according to a new clinical report from the American Academy of Pediatrics (AAP).

In the clinical report, "Returning to Learning Following a Concussion," released Sunday, Oct. 27 at the AAP National Conference & Exhibition in Orlando, the AAP offers guidance to pediatricians caring for children and adolescents after suffering a concussion.

"Students appear physically normal after a concussion, so it may be difficult for teachers and administrators to understand the extent of the child's injuries and recognize the potential need for academic adjustments," said Mark Halstead, MD, FAAP, a lead author of the clinical report. "But we know that children who've had a concussion may have trouble learning new material and remembering what they've learned, and returning to academics may worsen concussion symptoms."

Research has shown that a school-aged student usually recovers from a concussion within three weeks. If symptoms are severe, some students may need to stay home from school after a concussion. If symptoms or mild or tolerable, the parent may consider returning him or her to school, perhaps with some adjustments. Students with severe or prolonged symptoms lasting more than 3 weeks may require more formalized academic accommodations.

The AAP recommends a collaborative team approach to help a student recovering from a concussion. This team should consist of the child or adolescent's pediatrician, family members and individuals at the child's school responsible for both the student's academic schedule and physical activity. Detailed guidance on returning to sports and physical activities is contained in the 2010 AAP clinical report, "Sport-Related Concussion in Children and Adolescents."

A symptom checklist can help evaluate what symptoms the student is experiencing, and how severe they are.

"Every concussion is unique and symptoms will vary from student to student, so managing a student's return to the classroom will require an individualized approach," said Dr. Halstead. "The goal is to minimize disruptions to the student's life and return the student to school as soon as possible, and as symptoms improve, to increase the student's social, mental and physical activities."

Because relatively little research has been conducted on how concussion affects students' learning, the AAP based its report primarily on expert opinion and adapted it from a concussion management program developed at the Rocky Mountain Hospital for Children, Center for Concussion in Denver, Colo. The AAP calls for further research on the effects and role of cognitive rest after concussion to improve understanding of the best ways to help a student recovering from a concussion.

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Preschoolers learn better with midday naps

Research shows that a midday nap helps preschool children retain what they learned that morning showing how important sleep is for learning and creating memories.

A midday nap can help pre-school children remember what they learned in the morning, according to a study by psychologists in the US.

The research suggests that carers and nurseries that phase out after-lunch sleeps may be harming children's ability to learn, by disrupting the way their brains store memories.

Pre-schoolers who went without a midday sleep fared worse on memory tests than those who napped. They also failed to improve their scores even after a good night's sleep, the researchers found.

The findings highlight the crucial role of sleep in consolidating memories, a process that underpins the brain's ability to learn new information.

The children who benefited most were "habitual nappers" who would sleep when carers encouraged them to, rather than more mature children who had outgrown the need for a nap.

For the study, psychologists went into pre-school classrooms and taught 40 children aged three to nearly five years old a simple computer game. It required them to memorize the positions on a grid of images including a cat, an umbrella, and a policeman. The children were trained from 10am until they could remember the positions of around 75% of the pictures.

The scientists visited each child twice over the course of the study. On one visit, the child slept for an hour or so between 1pm and 3pm, and stayed awake on the other. To see how sleep affected their memory, the scientists tested each child again later the same afternoon.

Those who napped saw no change in their morning score of 75%, but the ones who stayed awake fared much worse, averaging scores of 65%, according to a report in the Proceedings of the National Academy of Sciences.

"If they stayed awake they forgot more of the items they had remembered in the morning, whereas if they took a nap, they remembered all the items they had learned in the morning," said Rebecca Spencer at the University of Massachusetts in Amherst.

To check whether the nappers were simply more alert and attentive than the others, the scientists returned the next day and tested the children again. Their scores did not change, suggesting that daytime sleep was crucial.

Spencer said that parents and pre-schools are steadily cutting down the time given to children's naps to fit a convenient schedule, or to make more time for a curriculum.

"You often see children forced out of napping, and hopefully this will help parents and pre-schools to understand that maybe that's not the best decision, and that a nap is an important part of the day," said Spencer.

"This is the science that's needed to preserve nap time. If our goals are to prepare children for early education, the naps are consistent with that goal because it's really helping them to learn," she added.

The scientists went on to look at the brain activity of 14 children while they slept in the unversity's sleep lab. They found that children with the best memory recall experienced more "sleep spindles" – brief bursts of activity thought to happen when the brain shunts memories from short-term storage in the hippocampus to the neocortex.

"This demonstrates very vividly the value of sleep for consolidating memories. Very young children find it quite difficult to retain information over the course of a full day, so in those circumstances, a nap is going to be useful for ensuring that whatever they learn is retained in the longer term," said Gareth Gaskell, professor of psychology at York University.

"At these ages, children are shifting from multiple sleeps in 24 hours to a single sleep overnight. It may well be that non-habitual nappers are becoming more adult-like, and have got that little bit further in the process."

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Phobias can be treated during sleep

A study claims that fears and phobias can be treated while people are sleeping.

Tallying sleep's benefits can seem as endless as counting sheep. Now, researchers say they might have found another benefit of sleep — it may be a good time to calm fears.

A fear was reduced in people by repeatedly exposing them to the fear memory during sleep, according to a study published online Sunday in the journal Nature Neuroscience.

"It's a novel finding," says Katherina Hauner, the study's lead author. "We showed a small but significant decrease in fear. The bigger picture is that, perhaps, the treatment of phobias can be enhanced during sleep." Hauner conducted the research when she was a postdoctoral fellow in neurology at the Northwestern University Feinberg School of Medicine in Chicago.

The study included 15 healthy young adults who received mild electric shocks while viewing two faces. They were exposed to an odor when seeing each face and getting a shock. In doing so, the face and odor were associated with fear. When a subject was sleeping, an odor was continuously presented but without the associated faces and shocks. When the subjects woke up, they were shown both faces. Their fear reactions were lower for the face linked to the odor they smelled during their rest.

There may be an advantage to adding a nighttime component to exposure therapy, a treatment for phobias and post-traumatic stress disorder, says Hauner, assistant director of the Cognitive Neuroscience Laboratory at the Rehabilitation Institute of Chicago.

Exposure therapy involves exposing a patient to a feared object or situation without danger to reduce anxiety. A therapist usually uses this technique with a patient during the day.

It may be helpful for patients if they can experience changes in their fear responses during sleep when they are not aware of the process, Hauner says. In that way, they wouldn't have to go through confronting the feared object or situation as much as they would in current therapy, she says.

"This is a new area of research," she adds. Further testing could look at whether the approach would produce long-term effects, she says. Also, the study examined memories created in a lab so further research could look at whether the approach would have an effect on pre-existing fear memories, she says.

"The study is important and exciting because it's a reminder that sleep doesn't just improve or consolidate memory," says Mark Mahowald, an American Academy of Neurology member who was not involved in the research. "It can extinguish memories."

"The extinction of memory during sleep could be important for people with PTSD and chemical dependencies," says Mahowald, a professor of neurology at the University of Minnesota Medical School in Minneapolis. "Further research could look at relapse prevention."

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Insight into the brain and Alzheimer's disease

This article discusses research into the functioning of the brain associated with Alzheimer's disease.

Scientists of the Charité -- Universitätsmedizin Berlin and the German Center for Neurodegenerative Diseases (DZNE) have managed to acquire new insights into the functioning of a region in the brain that normally is involved in spatial orientation, but is damaged by the Alzheimer's disease. They investigated how nerve signals are suppressed inside the so-called entorhinal cortex. According to the researchers, this neuronal inhibition leads nerve cells to synchronize their activity. The results of this study are now published in Neuron.

The entorhinal cortex is a link between the brain's memory centre, the hippocampus, and the other areas of the brain. It is, however, more than an interface that only transfers nervous impulses. The entorhinal cortex also has an independent role in learning and thinking processes. This is particularly applicable for spatial navigation. "We know precious little about how this happens," says Prof. Dietmar Schmitz, a researcher at the Cluster of Excellence NeuroCure at the Charité -- Universitätsmedizin Berlin and Site Speaker for the DZNE in Berlin. "This is why we are investigating in animal models how the nerve cells within the entorhinal cortex are connected with each other."

Signals wander inside the brain as electrical impulses from nerve cell to nerve cell. In general, signals are not merely forwarded. Rather, operation of the brain critically depends on the fact that the nerve impulses in some situations are activated and in other cases suppressed. A correct balance between suppression and excitation is decisive for all brain processes. "Until now research has mainly concentrated on signal excitation within the entorhinal cortex. This is why we looked into inhibition and detected a gradient inside the entorhinal cortex," explains Dr. Prateep Beed, lead author of the study. "This means that nerve signals are not suppressed equally. The blockage of the nerve signals is weaker in certain parts of the entorhinal cortex and stronger in others. The inhibition has, so to speak, a spatial profile."

When the brain is busy, nerve cells often coordinate their operation. In an electroencephalogram (EEG) -- a recording of the brain's electrical activity -- the synchronous rhythm of the nerve cells manifests as a periodic pattern. "It is a moot question as to how nerve cells synchronize their behavior and how they bring about such rhythms," says Beed. As he explains, it is also unclear whether these oscillations are only just a side effect or whether they trigger other phenomena. "But it has been demonstrated that neuronal oscillations accompany learning processes and even happen during sleep. They are a typical feature of the brain's activity," describes the scientist. "In our opinion, the inhibitory gradient, which we detected, plays an important role in creating the synchronous rhythm of the nerve cells and the related oscillations."

In the case of Alzheimer's, the entorhinal cortex is among the regions of the brain that are the first to be affected. "In recent times, studies related to this brain structure have increased. Here, already in the early stages of Alzheimer's, one finds the protein deposits that are typical of this disease," explains Schmitz, who headed the research. "It is also known that patients affected by Alzheimer's have a striking EEG. Our studies help us to understand how the nerve cells in the entorhinal cortex operate and how electrical activities might get interrupted in this area of the brain."

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Keeping the brain healthy with exercise

New research shows that an active lifestyle can help keep the brain healthy in addition to the body.

An active lifestyle has long been promoted as a way to keep the heart pumping strong. Now new research shows that physical activity may help to keep the brain robust as well, preserving areas critical for thinking and memory and possibly even helping to ward off Alzheimer’s disease in old age.

Earlier studies have linked activities like walking and ballroom dancing to a lower risk for dementia. Exercise is known to boost cardiovascular health, and what’s good for the heart is good for the brain, the thinking goes.

Now scientists at the University of California, Los Angeles, have examined the effects of remaining active directly on the brain. For the report, they looked at detailed records of 876 older adults, average age 78, over decades. Some had Alzheimer’s disease or serious memory problems, while others were cognitively alert. Along with medical reports, the records included information on how often each participant engaged in activities like gardening and yard work, bicycling or riding an exercise bike, dancing, and recreational activities like golfing, walking or tennis.

"We had 20 years of clinical data on this group, including body mass index and lifestyle habits," said Dr. Cyrus Raji, a radiology resident at U.C.L.A, one of the study leaders. "We drew our patients from four sites across the country, and we were able to assess energy output in the form of kilocalories per week." The findings were reported at the annual meeting of the Radiological Society of North America.

Using specialized brain scans, the researchers created 3-D maps of the brain, including areas of gray matter critical for thinking and memory. "Gray matter volume is a key marker of brain health. Larger gray matter volume means a healthier brain. Shrinking volume is seen in Alzheimer's disease," Dr. Raji said.

The researchers found that those men and women who were most active had more gray matter in parts of the brain critical for memory and thinking. They took into account such factors as age, head size, body mass index, and education, which can influence Alzheimer’s risk.

"The areas of the brain that benefited from an active lifestyle are the ones that consume the most energy and are very sensitive to damage," Dr. Raji said. "What struck me most about the study results is that it is not one but a combination of lifestyle choices and activities that benefit the brain."

Dr. Raji said the benefits of an active lifestyle on the brain were likely due to improved blood vessel health. "Virtually all of the physical activities examined in this study are some variation of aerobic physical activity, which we know from other work can improve cerebral blood flow and strengthen neuronal connections," he said. Although more research is needed in this area, “our initial results show that brain aging can be alleviated through an active lifestyle," he said.

In a separate study also presented at the Radiological Society of North America’s annual meeting, scientists at the Medical University of South Carolina in Charleston reported that men and women with Alzheimer’s disease had different patterns of gray matter loss, or atrophy.

"We found that the extent and distribution of regional gray matter volume loss in the brain was strongly influenced by gender," said lead researcher Dr. Maria Vittoria Spampinato. "The female patients in our study initially had more gray matter atrophy than the male patients, but over time, the men caught up. In the men, the disease developed more aggressively in a shorter period of time."

The findings could have implications for monitoring the effects of new Alzheimer’s drugs on the brain. "Knowing the difference between the male and female patterns of atrophy will help researchers better decipher a patient's response to drug therapy," Dr. Spampinato said.

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Vitamin D deficiency linked with cognitive impairment in adults

This study shows that Vitamin D deficiency, or hypovitaminosis D, is linked with cognitive impairment in adults affecting their memory.

Hypovitaminosis D is associated with global cognitive impairment in adults. It remains unclear which domain–specific cognitive functions are affected with hypovitaminosis D. Lower serum 25OHD concentrations predict executive dysfunctions, especially on mental shifting, information updating and processing speed. The association with episodic memory remains uncertain.

Abstract

Background: Hypovitaminosis D is associated with global cognitive impairment in adults. It remains unclear which domain-specific cognitive functions are affected with hypovitaminosis D. Objective. To systematically review and quantitatively synthesize the association of serum 25-hydroxyvitamin D (25OHD) concentrations with episodic memory and executive functions in adults. Methods: A Medline and PsycINFO^®libraries search was conducted on May 2012, with no limit of date, using the Medical Subject Headings (MeSH) terms “Vitamin D” OR “Hydroxycholecalciferols” combined with the MeSH terms “Memory” OR “Memory Disorders” OR “Executive Function” OR “Attention” OR “Cognition” OR “Cognition disorders” OR “Dementia” OR “Alzheimer disease” OR “Neuropsychological Tests”. Fixed-effects meta-analysis was performed from 12 eligible studies using an inverse-variance method. Results: Of the 285 selected studies, 14 observational studies (including 3 prospective cohort studies) and 3 interventional studies met the selection criteria. All were of good quality. The number of participants ranged from 44–5,692 community-dwellers (0–100% women). In the pooled analysis, although episodic memory disorders showed only modest association with lower 25OHD concentrations (summary effect size of the difference (ES) = −0.09 [95%CI:−0.16;−0.03]), associations of greater magnitude were found with executive dysfunctions (processing speed: mean difference of Trail Making Test (TMT)-A score = 4.0 [95%CI:1.20;6.83]; mental shifting: mean difference of TMT-B score = 12.47 [95%CI:6.78;18.16]; information updating tests: ES = −0.31 [95%CI:−0.5;−0.09]). The pooled risk of incident decline of TMT-B score was OR = 1.25 [95%CI:1.05;1.48] in case of initial lower 25OHD concentrations. Vitamin D repletion resulted in improved executive functions (ES = −0.50 [95%CI:−0.69;−0.32] for before-and-after comparison), but exhibited no difference with control groups (ES = 0.14 [95%CI:−0.04;0.32] for between-group comparison after intervention). Conclusion: Lower serum 25OHD concentrations predict executive dysfunctions, especially on mental shifting, information updating and processing speed. The association with episodic memory remains uncertain.

Methods

• A Medline and PsycINFO libraries search was conducted on May 2012, with no limit of date, using the Medical Subject Headings (MeSH) terms “Vitamin D” OR “Hydroxycholecalciferols” combined with the MeSH terms “Memory” OR “Memory Disorders” OR “Executive Function” OR “Attention” OR “Cognition” OR “Cognition disorders” OR “Dementia” OR “Alzheimer disease” OR “Neuropsychological Tests”.
• Fixed–effects meta–analysis was performed from 12 eligible studies using an inverse–variance method.

Results

• Of the 285 selected studies, 14 observational studies (including 3 prospective cohort studies) and 3 interventional studies met the selection criteria.
• All were of good quality. The number of participants ranged from 44–5,692 community–dwellers (0–100% women).
• In the pooled analysis, although episodic memory disorders showed only modest association with lower 25OHD concentrations (summary effect size of the difference (ES) = –0.09), associations of greater magnitude were found with executive dysfunctions (processing speed: mean difference of Trail Making Test (TMT)–A score = 4.0 [95%CI:1.20;6.83]; mental shifting: mean difference of TMT–B score = 12.47 [95%CI:6.78;18.16]; information updating tests: ES = –0.31).
• The pooled risk of incident decline of TMT–B score was OR = 1.25 [95%CI:1.05;1.48] in case of initial lower 25OHD concentrations.
• Vitamin D repletion resulted in improved executive functions, but exhibited no difference with control groups (ES = 0.14 [95%CI:–0.04;0.32] for between–group comparison after intervention).

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When you should talk to a doctor about sleep issues

This article discusses signs that indicate you should talk to a doctor about sleep issues.

According to the Centers for Disease Control (CDC), about 70 million Americans suffer from chronic sleep problems. Unfortunately, we live in a fast-paced society where sleep is not always a priority. We often overlook feeling tired and sleep deprived, chalking it up to a necessary part of a busy life. But besides the obvious impact on quality of life, sleep issues have also been linked to injuries, chronic diseases, mental illnesses, increased health care costs, and lost work productivity.

If you regularly have trouble falling or staying asleep (insomnia), are tired during the day (even after getting seven or more hours of sleep the night before), or notice that your abilities to perform daily functions are reduced, you may have a sleep disorder. Start by keeping track of your sleeping patterns. Record what time you go to sleep, how many times you wake up during the night, what time you wake up, and how you feel during the day. Take note of clues like the following:

• nodding off while driving
• struggling to stay awake when inactive, such as when watching television or reading
• difficulty paying attention or concentrating at work, school, or home
• performance problems at work or school
• getting told by others that you look sleepy often
• difficulty with your memory
• slowed responses
• difficulty controlling your emotions
• needing to take naps almost every day

If you experience one or more of the symptoms above, you should seek the help of a professional who can determine what is preventing you from experiencing quality sleep and help to address the problem. In some cases, disturbed sleep can be caused by sleep apnea, a chronic condition in which you have one or more pauses in breathing or shallow breaths while you sleep. Many people don’t even know they suffer from this condition, but it’s important to find out what’s causing it because it can lead to an increased risk of more serious health conditions like heart attack, diabetes, stroke, and obesity.

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Childhood Epilepsy, Memory, and Health Quality - No Connection to Seizure Frequency

Children with epilepsy and poor memory, in this study,  appear to have lower health-related quality of life.

Interestingly, this finding is not connected to seizure frequency.

As an illness, there is an experience that is broader than just the "seizures". 

Ask your neurologist about cognitive, attention, and emotional problems. Assess your child's sleep. Assess the effects of medications. Bone health, nutrition, weight gain and loss are all common problems. - JR

Poor memory in children with epilepsy linked to lower health related quality of life

(dailyRx News) Memory is often an area of concern for people with epilepsy. For children who are just learningabout the world around them, memory can be of particular importance to their physical, mental, emotional and social development.

A recent study investigated the link between memory and health-related quality of life - or how overall well-being is affected over time by disease, disability or other health issues - in children with epilepsy.

The study found that verbal, emotional difficulty and behavioral problems were associated with a lower health-related quality of life more than other factors, including frequent and intense seizures.

Marianne Hrabok, PhD, of the Alberta Children’s Hospital Research Insititute in Calgary, Alberta, Canada, and colleagues studied 90 children with epilepsy at a children’s hospital.

The number and frequency of seizures in the children varied. Thirty-seven percent of children had fewer than one seizure a month while 15 percent had more than one seizure a day.

Verbal skills and health-related quality of life assessments were examined. The researchers also looked at intellectual function, executive function, behavior and ability to adapt.

Details on socio-demographic factors and neurological status were included in the study.

Gender, age and socioeconomic status are examples of socio-demographic factors. Number of antiepileptic drugs and seizure severity are examples of neurological status.

The researchers found that health-related quality of life was not associated with socio-demographic and neurologic factors.

However, neuropsychological factors - including verbal memory, IQ, executive function, emotional and behavioral function and adaptability - were associated with health-related quality of life. Memory, emotional function and behavioral function had a particular relationship to health-related quality of life.

Those with low verbal memory had a two times greater risk of low health-related quality of life than those who did not have low verbal memory. Those with emotional and behavioral difficulty had a 10 times greater risk of low health-related quality life than those without the difficulty.

Having both low verbal memory and emotional and behavioral difficulty resulted in a risk 17 times greater than not having those difficulties.

The study authors believe these results showed the importance in neuropsychological assessment. Identifying those with poor memory and emotional function could help doctors identify those more likely to have a low health-related quality of life.

The authors suggested that psychosocial interventions for children with epilepsy include a team of health professionals with varying disciplines, an emphasis on involvement of the parents, psychological education, cognitive and behavioral strategies and the development of coping skills. Past studies have shown that a six-week program that includes these factors can improve health-related quality of life.

The study was published in Pediatrics. The research received no external funding. The authors did not report any conflicts of interest.

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