Mindfulness Improves Reading Ability, Working Memory, and Task-Focus

If you think your inability to concentrate is a hopeless condition, think again –– and breathe, and focus. According to a study by researchers at the UC Santa Barbara, as little as two weeks of mindfulness training can significantly improve one’s reading comprehension, working memory capacity, and ability to focus.

Their findings were recently published online in the empirical psychology journal Psychological Science.

"What surprised me the most was actually the clarity of the results," said Michael Mrazek, graduate student researcher in psychology and the lead and corresponding author of the paper, "Mindfulness Training Improves Working Memory Capacity and GRE Performance While Reducing Mind Wandering." "Even with a rigorous design and effective training program, it wouldn’t be unusual to find mixed results. But we found reduced mind-wandering in every way we measured it."

Many psychologists define mindfulness as a state of non-distraction characterized by full engagement with our current task or situation. For much of our waking hours, however, we are anything but mindful. We tend to replay past events –– like the fight we just had or the person who just cut us off on the freeway –– or we think ahead to future circumstances, such as our plans for the weekend.

Mind-wandering may not be a serious issue in many circumstances, but in tasks requiring attention, the ability to stay focused is crucial.

To investigate whether mindfulness training can reduce mind-wandering and thereby improve performance, the scientists randomly assigned 48 undergraduate students to either a class that taught the practice of mindfulness or a class that covered fundamental topics in nutrition. Both classes were taught by professionals with extensive teaching experience in their fields. Within a week before the classes, the students were given two tests: a modified verbal reasoning test from the GRE (Graduate Record Examination) and a working memory capacity (WMC) test. Mind-wandering during both tests was also measured.

The mindfulness classes provided a conceptual introduction along with practical instruction on how to practice mindfulness in both targeted exercises and daily life. Meanwhile, the nutrition class taught nutrition science and strategies for healthy eating, and required students to log their daily food intake.

Within a week after the classes ended, the students were tested again. Their scores indicated that the mindfulness group significantly improved on both the verbal GRE test and the working memory capacity test. They also mind-wandered less during testing. None of these changes were true of the nutrition group.

"This is the most complete and rigorous demonstration that mindfulness can reduce mind-wandering, one of the clearest demonstrations that mindfulness can improve working memory and reading, and the first study to tie all this together to show that mind-wandering mediates the improvements in performance," said Mrazek. He added that the research establishes with greater certainty that some cognitive abilities often seen as immutable, such as working memory capacity, can be improved through mindfulness training.

Mrazek and the rest of the research team –– which includes Michael S. Franklin, project scientist; mindfulness teacher and research specialist Dawa Tarchin Phillips; graduate student Benjamin Baird; and senior investigator Jonathan Schooler, professor of psychological and brain sciences –– are extending their work by investigating whether similar results can be achieved with younger populations, or with web-based mindfulness interventions. They are also examining whether or not the benefits of mindfulness can be compounded by a program of personal development that also targets nutrition, exercise, sleep, and personal relationships.

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The neuroscience of finding your lost keys

Ever find yourself racking your brain on a Monday morning to remember where you put your car keys?

When you do find those keys, you can thank the hippocampus, a brain region responsible for storing and retrieving memories of different environments-such as that room where your keys were hiding in an unusual spot.

Now, scientists have helped explain how the brain keeps track of the incredibly rich and complex environments people navigate on a daily basis. They discovered how the dentate gyrus, a subregion of the hippocampus, helps keep memories of similar events and environments separate, a finding they reported March 20 in eLife. The findings, which clarify how the brain stores and distinguishes between memories, may also help identify how neurodegenerative diseases, such as Alzheimer’s disease, rob people of these abilities.

"Everyday, we have to remember subtle differences between how things are today, versus how they were yesterday - from where we parked our car to where we left our cellphone," says Fred H. Gage, senior author on the paper and the Vi and John Adler Chair for Research on Age-Related Neurodegenerative Disease at Salk. "We found how the brain makes these distinctions, by storing separate ‘recordings’ of each environment in the dentate gyrus."

The process of taking complex memories and converting them into representations that are less easily confused is known as pattern separation. Computational models of brain function suggest that the dentate gyrus helps us perform pattern separation of memories by activating different groups of neurons when an animal is in different environments.

However, previous laboratory studies found that in fact the same populations of neurons in the dentate gyrus are active in different environments, and that the way the cells distinguished new surroundings was by changing the rate at which they sent electrical impulses. This discrepancy between theoretical predictions and laboratory findings has perplexed neuroscientists and obscured our understanding of memory formation and retrieval.

To explore this mystery more deeply, the Salk scientists compared the functioning of the mouse dentate gyrus and another region of the hippocampus, known as CA1, using laboratory techniques for tracking the activity of neurons at multiple time points.

First, the researchers took mice from their original chamber and placed them in a novel chamber to learn about a new environment (episode 1). Meanwhile, they recorded which hippocampal neurons were active as the animals responded to their new surroundings. Subsequently, the mice were either returned to that same novel chamber to measure memory recall or to a slightly modified chamber to measure discrimination (episode 2). The active neurons in episode 2 were also labeled in order to determine if the neurons activated in episode 1 were used in the same way for recall and for discrimination of small differences between environments.

When the researchers compared the neural activity during the two episodes, they found that the dentate gyrus and CA1 sub-regions functioned differently. In CA1, the same neurons that were active during the initial learning episode were also active when the mice retrieved the memories. In the dentate gyrus, however, distinct groups of cells were active during the learning episodes and retrieval. Also, exposing the mice to two subtly different environments activated two distinct groups of cells in the dentate gyrus.

"This finding supported the predictions of theoretical models that different groups of cells are activated during exposure to similar, but distinct, environments," says Wei Deng, a Salk postdoctoral research and first author on the paper. "This contrasts with the findings of previous laboratory studies, possibly because they looked at different sub-populations of neurons in the dentate gyrus."

The Salk researchers’ findings suggest that recalling a memory-such as the location of missing keys-does not always involve reactivation of the same neurons that were active during encoding. More importantly, the results indicate that the dentate gyrus performs pattern separation by using distinct populations of cells to represent similar but non-identical memories.

The findings help clarify the mechanisms that underpin memory formation and shed light on systems that are disrupted by injuries and diseases of the nervous system.

Brain Mapping Reveals Neurological Basis of Decision-Making in Rats

Scientists at UC San Francisco have discovered how memory recall is linked to decision-making in rats, showing that measurable activity in one part of the brain occurs when rats in a maze are playing out memories that help them decide which way to turn. The more they play out these memories, the more likely they are to find their way correctly to the end of the maze.

In their study, reported this week in the journal Neuron, the UCSF researchers implanted electrodes directly on a region of the rat brain known as the hippocampus, which is already known to play a key role in the formation and recall of memory. This same region is active when animals are learning, and it is damaged in people who have Alzheimer’s and post-traumatic stress disorder.

The study showed that when the rats paused before an upcoming choice, sometimes the hippocampus was more active and sometimes it was less active. When it was more active it did a better job of recalling memories of places the animal could go next, and the animal was more likely to go to the right place.

“We know that considering possibilities is important for decision-making, but we haven’t really known how this happens in the brain,” said neuroscientist Loren Frank, PhD, who led the research. Frank is an associate professor of physiology and a member of the UCSF Center for Integrative Neuroscience at UCSF.

The work builds upon several years of investigations in Frank’s laboratory that have shown how activity in the hippocampus is a fundamental constituent of memory retrieval. Their recent work shows that this activity is not just about remembering the past – it is also important for thinking about the future. When the brain does a better job of thinking about future possibilities, it makes better decisions.

Next, the team wants to tease out why sometimes the hippocampus does not do a good job of playing out future options. Problems with memory and decision-making are central to age-related cognitive decline, and a deeper understanding of how this works could pave the way for interventions that make the brain work better.

Sleep consolidates memories for competing tasks

Sleep plays an important role in the brain’s ability to consolidate learning when two new potentially competing tasks are learned in the same day, research at the University of Chicago demonstrates.

Other studies have shown that sleep consolidates learning for a new task. The new study, which measured starlings’ ability to recognize new songs, shows that learning a second task can undermine the performance of a previously learned task. But this study is the first to show that a good night’s sleep helps the brain retain both new memories.

Starlings provide an excellent model for studying memory because of fundamental biological similarities between avian and mammalian brains, scholars wrote in the paper, “Sleep Consolidation of Interfering Auditory Memories in Starlings,” published in the current online edition of Psychological Science.

“These observations demonstrate that sleep consolidation enhances retention of interfering experiences, facilitating daytime learning and the subsequent formation of stable memories,” the authors wrote.

The paper was written by Timothy Brawn, a graduate researcher in psychology at UChicago; Howard Nusbaum, professor of psychology; and Daniel Margoliash, professor of psychology, organismal biology and anatomy. Nusbaum is a leading expert on learning, and Margoliash is a pioneer in the research of brain function and its development in birds.

Study indicates reverse impulses clear useless information, prime brain for learning

When the mind is at rest, the electrical signals by which brain cells communicate appear to travel in reverse, wiping out unimportant information in the process, but sensitizing the cells for future sensory learning, according to a study of rats conducted by researchers at the National Institutes of Health.

The finding has implications not only for studies seeking to help people learn more efficiently, but also for attempts to understand and treat post-traumatic stress disorder—in which the mind has difficulty moving beyond a disturbing experience.

During waking hours, brain cells, or neurons, communicate via high-speed electrical signals that travel the length of the cell. These communications are the foundation for learning. As learning progresses, these signals travel across groups of neurons with increasing rapidity, forming circuits that work together to recall a memory.

It was previously known that, during sleep, these impulses were reversed, arising from waves of electrical activity originating deep within the brain. In the current study, the researchers found that these reverse signals weakened circuits formed during waking hours, apparently so that unimportant information could be erased from the brain. But the reverse signals also appeared to prime the brain to relearn at least some of the forgotten information. If the animals encountered the same information upon awakening, the circuits re-formed much more rapidly than when they originally encountered the information.

"The brain doesn’t store all the information it encounters, so there must be a mechanism for discarding what isn’t important," said senior author R. Douglas Fields, Ph.D., head of the Section on Nervous System Development and Plasticity at the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), the NIH institute where the research was conducted. "These reverse brain signals appear to be the mechanism by which the brain clears itself of unimportant information."

Their findings appear in the Proceedings of the National Academy of Sciences.

The researchers studied the activity of rats’ brain cells from the hippocampus, a tube-like structure deep in the brain. The hippocampus relays information to and from many other regions of the brain. It plays an important role in memory, orientation, and navigation.

The classic understanding of brain cell activity is that electrical signals travel from dendrites—antenna-like projections at one end of the cell—through the cell body. From the cell body, they then travel the length of the axon, a single long projection at the other end of the cell. This electrical signal stimulates the release of chemicals at the end of the axon, which bind to dendrites on adjacent cells, stimulating these recipient cells to fire electrical signals, and so on. When groups of cells repeatedly fire in this way, the electrical signals increase in intensity.

Dr. Bukalo and her team examined electrical signals that traveled in reverse—from the cell’s axon, to the cell body, and out its many dendrites. This reverse firing happens during sleep and at rest, appearing to reset the cell, the researchers found.

After first stimulating the cells with reverse electrical impulses, the researchers next stimulated the dendrites again with electrical impulses traveling in the forward direction. In response, the neurons generated a stronger signal, with the connections appearing to strengthen with repeated electrical stimulation.

This pattern appears to underlie the formation of new memories. A connection that is reset but never stimulated again may simply fade from use over time, Dr. Bukalo explained. But when a cell is stimulated again, it fires a stronger signal and may be more easily synchronized to the reinforced signals of other brain cells, all of which act in concert over time.

Difficulty in Recognizing Faces in Autism Linked to Performance in a Group of Neurons

Neuroscientists at Georgetown University Medical Center (GUMC) have discovered a brain anomaly that explains why some people diagnosed with autism cannot easily recognize faces — a deficit linked to the impairments in social interactions considered to be the hallmark of the disorder.

They also say that the novel neuroimaging analysis technique they developed to arrive at this finding is likely to help link behavioral deficits to differences at the neural level in a range of neurological disorders.

The final manuscript published March 15 in the online journal NeuroImage: Clinical, the scientists say that in the brains of many individuals with autism, neurons in the brain area that processes faces (the fusiform face area, or FFA) are too broadly “tuned” to finely discriminate between facial features of different people. They made this discovery using a form of functional magnetic resonance imaging (fMRI) that scans output from the blueberry-sized FFA, located behind the right ear.

“When your brain is processing faces, you want neurons to respond selectively so that each is picking up a different aspect of individual faces. The neurons need to be finely tuned to understand what is dissimilar from one face to another,” says the study’s senior investigator, Maximilian Riesenhuber, PhD, an associate professor of neuroscience at GUMC.

“What we found in our 15 adult participants with autism is that in those with more severe behavioral deficits, the neurons are more broadly tuned, so that one face looks more like another, as compared with the fine tuning seen in the FFA of typical adults,” he says.

“And we found evidence that reduced selectivity in FFA neurons corresponded to greater behavioral deficits in everyday face recognition in our participants. This makes sense. If your neurons cannot tell different faces apart, it makes it more difficult to tell who is talking to you or understand the facial expressions that are conveyed, which limits social interaction.”

Riesenhuber adds that there is huge variation in the ability of individuals diagnosed with autism to discriminate faces, and that some autistic people have no problem with facial recognition.

“But for those that do have this challenge, it can have substantial ramifications — some researchers believe deficits in face processing are at the root of social dysfunction in autism,” he says.

The neural basis for face processing

Neuroscientists have used traditional fMRI studies in the past to probe the neural bases of behavioral differences in people with autism, but these studies have produced conflicting results, says Riesenhuber.  “The fundamental problem with traditional fMRI techniques is that they can tell which parts of the brain become active during face processing, but they are poor at directly measuring neuronal selectivity,” he says, “and it is this neuronal selectivity that predicts face processing performance, as shown in our previous studies.”

To test their hypothesis that differences in neuronal selectivity in the FFA are foundational to differences in face processing abilities in autism, Riesenhuber and the study’s lead author, neuroscientist Xiong Jiang, PhD, developed a novel brain imaging analysis technique, termed local regional heterogeneity, to estimate neuronal selectivity.

“Local regional heterogeneity, or Hcorr, as we called it, is based on the idea that neurons that have similar selectivities will on average show similar responses, whereas neurons that like different stimuli will respond differently,” says Jiang. “This means that individuals with face processing deficits should show more homogeneous activity in their FFA than individuals with more typical face recognition abilities.”

They tested the method in 15 adults with autism and 15 adults without the disorder. The autistic participants also underwent a standard assessment of social/behavioral functioning.

The researchers found that in each autistic participant, behavioral ability to tell faces apart was tightly linked to levels of tuning specificity in the right FFA as estimated with Hcorr. This finding was confirmed by another advanced imaging technique, fMRI rapid adaptation, shown by the group in previous work to be a good estimator of neuronal selectivity.

“Compared to the more well-established fMRI-rapid adaptation technique, Hcorr has several significant advantages,” says Jiang. “Hcorr is more sensitive and can estimate neuronal selectivity as well as fMRI rapid adaptation, but with much shorter scans, and Hcorr can even estimate neuronal selectivity using data from resting state scans, thus making the technique suitable even for individuals that cannot perform complicated tasks in the scanner, such as low-functioning autistic adults, or young children.”

“The study suggests that, just as in typical adults, the FFA remains the key region responsible for face processing and that changes in neuronal selectivity in this area are foundational to the variability in face processing abilities found in autism. Our study identifies a clear target for intervention,” says Riesenhuber. Indeed, after the study was completed, the researchers successfully attempted to improve facial recognition skills in an autistic participant. They showed the participant pairs of faces that were very dissimilar at first, but became increasingly similar, and found that FFA tuning improved along with behavioral ability to tell the faces apart. “This suggests high-level brain areas may still be somewhat plastic in adulthood,” says Riesenhuber.

Researchers Show that Suppressing the Brain’s “Filter” Can Improve Performance in Creative Tasks

The brain’s prefrontal cortex is thought to be the seat of cognitive control, working as a kind of filter that keeps irrelevant thoughts, perceptions and memories from interfering with a task at hand.

Now, researchers at the University of Pennsylvania have shown that inhibiting this filter can boost performance for tasks in which unfiltered, creative thoughts present an advantage.

The research was conducted by Sharon Thompson-Schill, the Christopher H. Browne Distinguished Professor of Psychology and director of the Center for Cognitive Neuroscience, and Evangelia Chrysikou, a member of her lab who is now an assistant professor at the University of Kansas. They collaborated with Roy Hamilton and H. Branch Coslett of the Department of Neurology at Penn’s Perelman School of Medicine and Abhishek Datta and Marom Bikson of the Department of Biomedical Engineering at the City College of New York.

Their work was published in the journal Cognitive Neuroscience.

Enhancing Cognition with Video Games: A Multiple Game Training Study

Background

Previous evidence points to a causal link between playing action video games and enhanced cognition and perception. However, benefits of playing other video games are under-investigated. We examined whether playing non-action games also improves cognition. Hence, we compared transfer effects of an action and other non-action types that required different cognitive demands.

Methodology/Principal Findings

We instructed 5 groups of non-gamer participants to play one game each on a mobile device (iPhone/iPod Touch) for one hour a day/five days a week over four weeks (20 hours). Games included action, spatial memory, match-3, hidden- object, and an agent-based life simulation. Participants performed four behavioral tasks before and after video game training to assess for transfer effects. Tasks included an attentional blink task, a spatial memory and visual search dual task, a visual filter memory task to assess for multiple object tracking and cognitive control, as well as a complex verbal span task. Action game playing eliminated attentional blink and improved cognitive control and multiple-object tracking. Match-3, spatial memory and hidden object games improved visual search performance while the latter two also improved spatial working memory. Complex verbal span improved after match-3 and action game training.

Conclusion/Significance

Cognitive improvements were not limited to action game training alone and different games enhanced different aspects of cognition. We conclude that training specific cognitive abilities frequently in a video game improves performance in tasks that share common underlying demands. Overall, these results suggest that many video game-related cognitive improvements may not be due to training of general broad cognitive systems such as executive attentional control, but instead due to frequent utilization of specific cognitive processes during game play. Thus, many video game training related improvements to cognition may be attributed to near-transfer effects.

Sleep Discovery Could Lead to Therapies That Improve Memory

A team of sleep researchers led by UC Riverside psychologist Sara C. Mednick has confirmed the mechanism that enables the brain to consolidate memory and found that a commonly prescribed sleep aid enhances the process. Those discoveries could lead to new sleep therapies that will improve memory for aging adults and those with dementia, Alzheimer’s and schizophrenia.

The groundbreaking research appears in a paper, “The Critical Role of Sleep Spindles in Hippocampal-Dependent Memory: A Pharmacology Study,” published in the Journal of Neuroscience.

Earlier research found a correlation between sleep spindles — bursts of brain activity that last for a second or less during a specific stage of sleep — and consolidation of memories that depend on the hippocampus. The hippocampus, part of the cerebral cortex, is important in the consolidation of information from short-term to long-term memory, and spatial navigation. The hippocampus is one of the first regions of the brain damaged by Alzheimer’s disease.

Mednick and her research team demonstrated, for the first time, the critical role that sleep spindles play in consolidating memory in the hippocampus, and they showed that pharmaceuticals could significantly improve that process, far more than sleep alone.

In addition to Mednick the research team includes: Elizabeth A. McDevitt, UC San Diego; James K. Walsh, VA San Diego Healthcare System, La Jolla, Calif; Erin Wamsley, St. Luke’s Hospital, St. Louis, Mo.; Martin Paulus, Stanford University; Jennifer C. Kanady, Harvard Medical School; and Sean P.A. Drummond, UC Berkeley.

“We found that a very common sleep drug can be used to increase verbal memory,” said Mednick, the lead author of the paper that outlines results of two studies conducted over five years with a $651,999 research grant from the National Institutes of Health. “This is the first study to show you can manipulate sleep to improve memory. It suggests sleep drugs could be a powerful tool to tailor sleep to particular memory disorders.”

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