Meditation's cognitive benefits - news reports
About these topic collections
I’ve been reporting on memory research for over ten years and these topic pages are simply collections of all the news items I have made on a particular topic. They do not pretend to be in any way exhaustive! I cover far too many areas within memory to come anywhere approaching that. What I aim to do is provide breadth, rather than depth. Outside my own area of cognitive psychology, it is difficult to know how much weight to give to any study (I urge you to read my blog post on what constitutes scientific evidence). That (among other reasons) is why my approach in my news reporting is based predominantly on replication and consistency. It's about the aggregate. So here is the aggregate of those reports I have at one point considered of sufficient interest to discuss. If you know of any research you would like to add to the collection, feel free to write about it in a comment (please provide a reference).
Three classroom experiments have found that students who meditated before a psychology lecture scored better on a quiz that followed than students who did not meditate. Mood, relaxation, and class interest were not affected by the meditation training.
The noteworthy thing is that the meditation was very very basic — six minutes of written meditation exercises.
The effect was stronger in classes where more freshmen students were enrolled, suggesting that the greatest benefit is to those students who have most difficulty in concentrating (who are more likely to drop out).
The finding suggests the value in teaching some active self-reflection strategies to freshmen, and disadvantaged ones in particular.
It’s reasonable to speculate that more extensive training might increase the benefits.
And in another recent meditation study, a two week mindfulness course significantly improved both Graduate Record Exam reading comprehension scores and working memory capacity.
The study involved 48 undergrads who either attended the mindfulness course or a nutrition class. Each 45-minute class met eight times over two weeks. Mindfulness training was associated with a 16-percentile boost in GRE scores, on average. Mind wandering also significantly decreased. The healthy nutrition course had no effect on any of these factors.
 Mindfulness Training Improves Working Memory Capacity and GRE Performance While Reducing Mind Wandering. Psychological Science.(2013).
Why do we find it so hard to stay on task for long? A recent study uses a new technique to show how the task control network and the default mode network interact (and fight each other for control).
The task control network (which includes the dorsal anterior cingulate and bilateral anterior insula) regulates attention to surroundings, controlling your concentration on tasks. The default mode network, on the other hand, becomes active when a person seems to be doing 'nothing', and becomes less active when a task is being performed.
The study shows that we work better and faster the better the default mode network is suppressed by the task control network. However, when the default mode network is not sufficiently suppressed by the task control network, it sends signals to the task control network, interfering with its performance (and we lose focus).
Interestingly, in certain conditions, such as autism, depression, and mild cognitive impairment, the default mode network remains unchanged whether the person is performing a task or interacting with the environment. Additionally, deficits in the functioning of the default mode network have been implicated in age-related cognitive decline.
The findings add a new perspective to our ideas about attention. One of the ongoing questions concerns the relative importance of the two main aspects of attention: focus, and resisting distraction. A lot of work in recent years has indicated that a large part of age-related cognitive decline is a growing difficulty in resisting distraction. Similarly, there is some evidence that people with a low working memory capacity are less able to ignore irrelevant information.
This recent finding, then, suggests that these difficulties in ignoring distracting / irrelevant stimuli reflect the failure of the task control network to adequately suppress the activity of the default mode network. This puts the emphasis back on training for focus, and may help explain why meditation practices are effective in improving concentration.
 Top-Down Regulation of Default Mode Activity in Spatial Visual Attention. The Journal of Neuroscience. 33(15), 6444 - 6453.(2013).
Here’s an encouraging study for all those who think that, because of age or physical damage, they must resign themselves to whatever cognitive impairment or decline they have suffered. In this study, older adults who had suffered from aphasia for a long time nevertheless improved their language function after six weeks of intensive training.
The study involved nine seniors with chronic aphasia and 10 age-matched controls. Those with aphasia were given six weeks of intensive and specific language therapy, after which they showed significantly better performance at naming objects. Brain scans revealed that the training had not only stimulated language circuits, but also integrated the default mode network (the circuits used when our brain is in its ‘resting state’ — i.e., not thinking about anything in particular), producing brain activity that was similar to that of the healthy controls.
Moreover, these new circuits continued to be active after training, with participants continuing to improve.
Previous research has implicated abnormal functioning of the default mode network in other cognitive disorders.
Although it didn’t reach significance, there was a trend suggesting that the level of integration of the default mode network prior to therapy predicted the outcome of the training.
The findings are especially relevant to the many seniors who no longer receive treatment for stroke damage they may have had for many years. They also add to the growing evidence for the importance of the default mode network. Changes in the integration of the default mode network with other circuits have also been implicated in age-related cognitive decline and Alzheimer’s.
Interestingly, some research suggests that meditation may help improve the coherence of brainwaves that overlap the default mode network. Meditation, already shown to be helpful for improving concentration and focus, may be of greater benefit for fighting age-related cognitive decline than we realize!
 Default-mode network functional connectivity in aphasia: Therapy-induced neuroplasticity. Brain and Language. 124(1), 45 - 55.(2013).
More evidence that even an 8-week meditation training program can have measurable effects on the brain comes from an imaging study. Moreover, the type of meditation makes a difference to how the brain changes.
The study involved 36 participants from three different 8-week courses: mindful meditation, compassion meditation, and health education (control group). The courses involved only two hours class time each week, with meditation students encouraged to meditate for an average 20 minutes a day outside class. There was a great deal of individual variability in the total amount of meditation done by the end of the course (210-1491 minutes for the mindful attention training course; 190-905 minutes for the compassion training course).
Participants’ brains were scanned three weeks before the courses began, and three weeks after the end. During each brain scan, the volunteers viewed 108 images of people in situations that were either emotionally positive, negative or neutral.
In the mindful attention group, the second brain scan showed a decrease in activation in the right amygdala in response to all images, supporting the idea that meditation can improve emotional stability and response to stress. In the compassion meditation group, right amygdala activity also decreased in response to positive or neutral images, but, among those who reported practicing compassion meditation most frequently, right amygdala activity tended to increase in response to negative images. No significant changes were seen in the control group or in the left amygdala of any participant.
The findings support the idea that meditation can be effective in improving emotional control, and that compassion meditation can indeed increase compassionate feelings. Increased amygdala activation was also correlated with decreased depression scores in the compassion meditation group, which suggests that having more compassion towards others may also be beneficial for oneself.
The findings also support the idea that the changes brought about by meditation endure beyond the meditative state, and that the changes can start to occur quite quickly.
These findings are all consistent with other recent research.
One point is worth emphasizing, in the light of the difficulty in developing a training program that improves working memory rather than simply improving the task being practiced. These findings suggest that, unlike most cognitive training programs, meditation training might produce learning that is process-specific rather than stimulus- or task-specific, giving it perhaps a wider generality than most cognitive training.
 Effects of mindful-attention and compassion meditation training on amygdala response to emotional stimuli in an ordinary, non-meditative state. Frontiers in Human Neuroscience. 6,(2012).
Full text available at http://www.frontiersin.org/human_neuroscience/10.3389/fnhum.2012.00292/a...
Meditation may improve multitasking
I recently reported that developing skill at video action games doesn’t seem to improve general multitasking ability, but perhaps another approach might be more successful. Meditation has, of course, been garnering growing evidence that it can help improve attentional control. A new study extends that research to multitasking in a realistic work setting.
The study involved three groups of 12-15 female human resource managers, of whom one group received eight weeks of mindfulness-based meditation training, another received eight weeks of body relaxation training, and another initially received no training (control), before receiving the mindfulness training after the eight weeks.
Before and after each eight-week period, the participants were given a stressful test of their multitasking abilities, requiring them to use email, calendars, instant-messaging, telephone and word-processing tools to perform common office tasks (scheduling a meeting; finding a free conference room; writing a draft announcement of the meeting, eating snacks and drinking water, writing a memo proposing a creative agenda item for the meeting). Necessary information came from emails, instant messages, telephone calls, and knocks on the door. The participants had 20 minutes to complete the tasks.
The meditation group reported lower levels of stress during the multitasking test compared to the control and relaxation groups. They also spent more time on tasks and switched tasks less often, while taking no longer to complete the overall job than the others. Both meditation and relaxation groups showed improved memory for the tasks they were performing.
After the control group underwent the meditation training, their results matched those of the meditation group.
The meditation training emphasized:
The relaxation training emphasized progressive tensing and relaxing of major muscle groups, aided by relaxation imagery.
It's interesting that overall time on task didn't change (the researchers remarked that the meditators didn't take any longer, but of course most of us would be looking for it to become shorter!), but I wouldn't read too much into it. The task was relatively brief. It would be interesting to see the effects over the course of, say, a day. Nor did the study look at how well the tasks were done.
But it is, of course, important that meditation training reduced task-switching and stress. Whether it also has a postitive effect on overall time and quality of work is a question for another day.
A recent imaging study has found that four weeks of a form of mindfulness meditation called integrative body–mind training (IBMT) improved white matter efficiency in areas surrounding the anterior cingulate cortex, compared to controls given relaxation training.
The anterior cingulate is part of the brain network related to self-regulation. Deficits in activation in this part of the brain have been associated with attention deficit disorder, dementia, depression, schizophrenia, and other disorders.
Using the data from a 2010 study involving 45 U.S. college students, and another involving 68 Chinese students, researchers found that axon density (one factor in white matter efficiency) had improved after two weeks, but not myelin formation. After a month (about 11 hours of meditation), both had improved. Mood improved by two weeks.
Previous studies involving computer-based training for improving working memory have found changes in myelination, but not axon density.
Meditators’ better cognitive control may be rooted in emotional regulation
Previous work has found that people who engage in meditation show higher levels of executive control on laboratory tasks.
An electrical signal called the Error Related Negativity (ERN) occurs in the brain within 100 ms of an error being committed. When meditators and non-meditators were given the Stroop Test, meditators not only tended to do better on the test, but their ERNs were stronger.
The interesting thing about this is that the best performers were those who scored highest on emotional acceptance. Mindful awareness was less important. It’s suggested that meditators may be able to control their behavior better not because of their sharper focus, but because they are more aware of their emotions and regulate them better.
Something to think about!
Levy, D. M., Wobbrock, J. O., Kaszniak, A. W., & Ostergren, M. (2012). The Effects of Mindfulness Meditation Training on Multitasking in a High-Stress Information Environment, 45–52. Full text available at http://faculty.washington.edu/wobbrock/pubs/gi-12.02.pdf
 Mechanisms of white matter changes induced by meditation. Proceedings of the National Academy of Sciences. 109(26), 10570 - 10574.(2012).
 Meditation, mindfulness and executive control: the importance of emotional acceptance and brain-based performance monitoring. Social Cognitive and Affective Neuroscience.(2012).
Meditation may improve multitasking:
IBMT improves white matter efficiency:
Meditators’ better cognitive control may be rooted in emotional regulation:
I’ve always felt that better thinking was associated with my brain working ‘in a higher gear’ — literally working at a faster rhythm. So I was particularly intrigued by the findings of a recent mouse study that found that brainwaves associated with learning became stronger as the mice ran faster.
In the study, 12 male mice were implanted with microelectrodes that monitored gamma waves in the hippocampus, then trained to run back and forth on a linear track for a food reward. Gamma waves are thought to help synchronize neural activity in various cognitive functions, including attention, learning, temporal binding, and awareness.
We know that the hippocampus has specialized ‘place cells’ that record where we are and help us navigate. But to navigate the world, to create a map of where things are, we need to also know how fast we are moving. Having the same cells encode both speed and position could be problematic, so researchers set out to find how speed was being encoded. To their surprise and excitement, they found that the strength of the gamma rhythm grew substantially as the mice ran faster.
The results also confirmed recent claims that the gamma rhythm, which oscillates between 30 and 120 times a second, can be divided into slow and fast signals (20-45 Hz vs 45-120 Hz for mice, consistent with the 30-55 Hz vs 45-120 Hz bands found in rats) that originate from separate parts of the brain. The slow gamma waves in the CA1 region of the hippocampus were synchronized with slow gamma waves in CA3, while the fast gamma in CA1 were synchronized with fast gamma waves in the entorhinal cortex.
The two signals became increasingly separated with increasing speed, because the two bands were differentially affected by speed. While the slow waves increased linearly, the fast waves increased logarithmically. This differential effect could have to do with mechanisms in the source regions (CA3 and the medial entorhinal cortex, respectively), or to mechanisms in the different regions in CA1 where the inputs terminate (the waves coming from CA3 and the entorhinal cortex enter CA1 in different places).
In the hippocampus, gamma waves are known to interact with theta waves. Further analysis of the data revealed that the effects of speed on gamma rhythm only occurred within a narrow range of theta phases — but this ‘preferred’ theta phase also changed with running speed, more so for the slow gamma waves than the fast gamma waves (which is not inconsistent with the fact that slow gamma waves are more affected by running speed than fast gamma waves). Thus, while slow and fast gamma rhythms preferred similar phases of theta at low speeds, the two rhythms became increasingly phase-separated with increasing running speed.
What’s all this mean? Previous research has shown that if inputs from CA3 and the entorhinal cortex enter CA1 at the same time, the kind of long-term changes at the synapses that bring about learning are stronger and more likely in CA1. So at low speeds, synchronous inputs from CA3 and the entorhinal cortex at similar theta phases make them more effective at activating CA1 and inducing learning. But the faster you move, the more quickly you need to process information. The stronger gamma waves may help you do that. Moreover, the theta phase separation of slow and fast gamma that increases with running speed means that activity in CA3 (slow gamma source) increasingly anticipates activity in the medial entorhinal cortex (fast gamma source).
What does this mean at the practical level? Well at this point it can only be speculation that moving / exercising can affect learning and attention, but I personally am taking this on board. Most of us think better when we walk. This suggests that if you’re having trouble focusing and don’t have time for that, maybe walking down the hall or even jogging on the spot will help bring your brain cells into order!
Pushing speculation even further, I note that meditation by expert meditators has been associated with changes in gamma and theta rhythms. And in an intriguing comparison of the effect of spoken versus sung presentation on learning and remembering word lists, the group that sang showed greater coherence in both gamma and theta rhythms (in the frontal lobes, admittedly, but they weren’t looking elsewhere).
So, while we’re a long way from pinning any of this down, it may be that all of these — movement, meditation, music — can be useful in synchronizing your brain rhythms in a way that helps attention and learning. This exciting discovery will hopefully be the start of an exploration of these possibilities.
 Speed Controls the Amplitude and Timing of the Hippocampal Gamma Rhythm. PLoS ONE. 6(6), e21408 - e21408.(2011).
Full text available at http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0021408
 From alpha to gamma: Electrophysiological correlates of meditation-related states of consciousness. Medical Hypotheses. 75, 218 - 224.(2010).
 Music increases frontal EEG coherence during verbal learning. Neuroscience Letters. 412(3), 217 - 221.(2007).
Following on from research showing that long-term meditation is associated with gray matter increases across the brain, an imaging study involving 27 long-term meditators (average age 52) and 27 controls (matched by age and sex) has revealed pronounced differences in white-matter connectivity between their brains.
The differences reflect white-matter tracts in the meditators’ brains being more numerous, more dense, more myelinated, or more coherent in orientation (unfortunately the technology does not yet allow us to disentangle these) — thus, better able to quickly relay electrical signals.
While the differences were evident among major pathways throughout the brain, the greatest differences were seen within the temporal part of the superior longitudinal fasciculus (bundles of neurons connecting the front and the back of the cerebrum) in the left hemisphere; the corticospinal tract (a collection of axons that travel between the cerebral cortex of the brain and the spinal cord), and the uncinate fasciculus (connecting parts of the limbic system, such as the hippocampus and amygdala, with the frontal cortex) in both hemispheres.
These findings are consistent with the regions in which gray matter increases have been found. For example, the tSLF connects with the caudal area of the temporal lobe, the inferior temporal gyrus, and the superior temporal gyrus; the UNC connects the orbitofrontal cortex with the amygdala and hippocampal gyrus
It’s possible, of course, that those who are drawn to meditation, or who are likely to engage in it long term, have fundamentally different brains from other people. However, it is more likely (and more consistent with research showing the short-term effects of meditation) that the practice of meditation changes the brain.
The precise mechanism whereby meditation might have these effects can only be speculated. However, more broadly, we can say that meditation might induce physical changes in the brain, or it might be protecting against age-related reduction. Most likely of all, perhaps, both processes might be going on, perhaps in different regions or networks.
Regardless of the mechanism, the evidence that meditation has cognitive benefits is steadily accumulating.
The number of years the meditators had practiced ranged from 5 to 46. They reported a number of different meditation styles, including Shamatha, Vipassana and Zazen.
 Enhanced brain connectivity in long-term meditation practitioners. NeuroImage. 57(4), 1308 - 1316.(2011).
The study involved 26 experienced Buddhist meditators and 40 control subjects. Scans of their brains while they played the "ultimatum game," in which the first player proposes how to divide a sum of money and the second can accept or reject the proposal, revealed that the two groups engaged different parts of the brain when making these decisions.
Consistent with earlier studies, controls showed increased activity in the anterior insula (involved in disgust and emotional reactions to unfairness and betrayal) when the offers were unfair. However the Buddhist meditators showed higher activity instead in the posterior insula (involved in interoception and attention to the present moment). In other words, rather than dwelling on emotional reactions and imaginary what-if scenarios, the meditators concentrated on the interoceptive qualities that accompany any reward, no matter how small.
The meditators accepted unfair offers on more than half of the trials, whereas controls only accepted unfair offers on a quarter of the trials.
Moreover, those controls who did in fact play the game ‘rationally’ (that is, mostly accepting the unfair offers) showed activity in the dorsolateral prefrontal cortex, while rational meditators displayed increased activity in the somatosensory cortex and posterior superior temporal cortex.
The most intriguing thing about all this is not so much that regular meditation might change the way your brain works (although that is undeniably interesting), but as a more general demonstration that we can train our brain to work in different ways. Something to add to the research showing how brain regions shift in function in those with physical damage to their brains or sense organs (eg, in those who become blind).
 Interoception drives increased rational decision-making in meditators playing the ultimatum game. Frontiers in Decision Neuroscience. 5, 49 - 49.(2011).
As I’ve discussed on many occasions, a critical part of attention (and working memory capacity) is being able to ignore distraction. There has been growing evidence that mindfulness meditation training helps develop attentional control. Now a new study helps fill out the picture of why it might do so.
The alpha rhythm is particularly active in neurons that process sensory information. When you expect a touch, sight or sound, the focusing of attention toward the expected stimulus induces a lower alpha wave height in neurons that would handle the expected sensation, making them more receptive to that information. At the same time the height of the alpha wave in neurons that would handle irrelevant or distracting information increases, making those cells less receptive to that information. In other words, alpha rhythm helps screen out distractions.
In this study, six participants who completed an eight-week mindfulness meditation program (MBSR) were found to generate larger alpha waves, and generate them faster, than the six in the control group. Alpha wave activity in the somatosensory cortex was measured while participants directed their attention to either their left hand or foot. This was done on three occasions: before training, at three weeks of the program, and after the program.
The MBSR program involves an initial two-and-a-half-hour training session, followed by daily 45-minute meditation sessions guided by a CD recording. The program is focused on training participants first to pay close attention to body sensations, then to focus on body sensations in a specific area, then being able to disengage and shifting the focus to another body area.
Apart from helping us understand why mindfulness meditation training seems to improve attention, the findings may also explain why this meditation can help sufferers of chronic pain.
 Effects of mindfulness meditation training on anticipatory alpha modulation in primary somatosensory cortex. Brain Research Bulletin. In Press, Corrected Proof,(Submitted).
Brain images of 16 participants in an 8-week mindfulness meditation program, taken two weeks before and after the program, have found measurable changes in brain regions associated with memory, sense of self, empathy and stress. Specifically, they showed increased grey-matter density in the left hippocampus, posterior cingulate cortex, temporo-parietal junction, and cerebellum, as well as decreased grey-matter density in the amygdala. Similar brain scans of a control group of non-meditators (those on a waiting list for the program) showed no such changes over time.
Although a number of studies have found differences in the brains of experienced meditators and those who don’t practice meditation, this is the first to demonstrate that those differences are actually produced by meditation.
The Mindfulness-Based Stress Reduction program involved weekly meetings that included practice of mindfulness meditation and audio recordings for guided meditation practice. Participants reported spending an average of 27 minutes each day practicing mindfulness exercises.
 Mindfulness practice leads to increases in regional brain gray matter density. Psychiatry Research: Neuroimaging. 191(1), 36 - 43.(2011).
Mindfulness Training had a positive effect on both working memory capacity and mood in a group of Marine reservists during the high-stress pre-deployment interval. While those who weren’t given the 8-week MT program, as well as those who spent little time engaging in mindfulness exercises, showed greater negative mood and decreased working memory capacity over the eight weeks, those who recorded high practice time showed increased capacity and decreased negative mood. A civilian control group showed no change in working memory capacity over the period. The program, called Mindfulness-based Mind Fitness Training (MMFT™), blended mindfulness skills training with concrete applications for the operational environment and information and skills about stress, trauma and resilience in the body. The researchers suggest that mindfulness training may help anyone who must maintain peak performance in the face of extremely stressful circumstances.
 Examining the protective effects of mindfulness training on working memory capacity and affective experience. Emotion (Washington, D.C.). 10(1), 54 - 64.(2010).
Another study showing the cognitive benefits of meditation has revealed benefits to perception and attention. The study involved 30 participants attending a three-month meditation retreat, during which they attended group sessions twice a day and engaging in individual practice for about six hours a day. The meditation practice involved sustained selective attention on a chosen stimulus (e.g., the participant’s breath). By midway through the retreat, meditators had become better at making fine visual distinctions, and better able to sustain attention during the half-hour test, compared to matched controls. Those who continued practicing meditation after the retreat still showed improvements in perception when they were retested about five months later.
 Intensive Meditation Training Improves Perceptual Discrimination and Sustained Attention. Psychological Science. 21(6), 829 - 839.(2010).
Great news for those who crave the benefits of meditation but find the thought a bit intimidating! While a number of studies have demonstrated that long-term mindfulness meditation practice promotes executive functioning and the ability to sustain attention, now a small study involving 49 students has found that as little as four sessions of 20 minutes produced a significant improvement in critical cognitive skills, compared to those who spent an equal amount of time listening to Tolkien's The Hobbit being read aloud. Both groups showed similar improved levels of mood, but only the meditation group improved their cognitive scores. While this group improved on all cognitive tasks, they did dramatically better when under stressful conditions, such as provided by increasingly challenging time-constraints, and particularly in the areas of attention and vigilance. Mindfulness training, as given here, focuses on breathing, letting go one’s thoughts, releasing sensory events that distract. It should be noted that no one is suggesting four days training produces a permanent effect! But it is encouraging to think that benefits might be achieved so quickly. The training also reduced fatigue and anxiety.
 Mindfulness meditation improves cognition: Evidence of brief mental training. Consciousness and Cognition. 19(2), 597 - 605.(2010).
Older news items (pre-2010) brought over from the old website
More on how meditation can improve attention
Another study adds to research showing meditation training helps people improve their ability to focus and ignore distraction. The new study shows that three months of rigorous training in Vipassana meditation improved people's ability to stabilize attention on target tones, when presented with tones in both ears and instructed to respond only to specific tones in one ear. Marked variability in response time is characteristic of those with ADHD.
 Mental Training Enhances Attentional Stability: Neural and Behavioral Evidence. J. Neurosci.. 29(42), 13418 - 13427.(2009).
Adding to the increasing evidence for the cognitive benefits of meditation, a new imaging study of 22 experienced meditators and 22 controls has revealed that meditators showed significantly larger volumes of the right hippocampus and the right orbitofrontal cortex, and to a lesser extent the right thalamus and the left inferior temporal gyrus. There were no regions where controls had significantly more gray matter than meditators. These areas of the brain are all closely linked to emotion, and may explain meditators' improved ability in regulating their emotions.
 The underlying anatomical correlates of long-term meditation: Larger hippocampal and frontal volumes of gray matter. NeuroImage. 45(3), 672 - 678.(2009).
Meditation technique can temporarily improve visuospatial abilities
And continuing on the subject of visual short-term memory, a study involving experienced practitioners of two styles of meditation: Deity Yoga (DY) and Open Presence (OP) has found that, although meditators performed similarly to nonmeditators on two types of visuospatial tasks (mental rotation and visual memory), when they did the tasks immediately after meditating for 20 minutes (while the nonmeditators rested or did something else), practitioners of the DY style of meditation showed a dramatic improvement compared to OP practitioners and controls. In other words, although the claim that regular meditation practice can increase your short-term memory capacity was not confirmed, it does appear that some forms of meditation can temporarily (and dramatically) improve it. Since the form of meditation that had this effect was one that emphasizes visual imagery, it does support the idea that you can improve your imagery and visual memory skills (even if you do need to ‘warm up’ before the improvement is evident).
 The enhancement of visuospatial processing efficiency through Buddhist Deity meditation. Psychological Science: A Journal of the American Psychological Society / APS. 20(5), 645 - 653.(2009).
Transcendental Meditation reduces ADHD symptoms among students
A pilot study involving 10 middle school students with ADHD has found that those who participated in twice-daily 10 minute sessions of Trancendental Meditation for three months showed a dramatic reduction in stress and anxiety and improvements in ADHD symptoms and executive function. The effect was much greater than expected. ADHD children have a reduced ability to cope with stress.
A second, recently completed study has also found that three months practice of the technique resulted in significant positive changes in brain functioning during visual-motor skills, especially in the circuitry of the brain associated with attention and distractibility. After six months practice, measurements of distractibility moved into the normal range.
Grosswald, S. J., Stixrud, W. R., Travis, F., & Bateh, M. A. (2008, December). Use of the Transcendental Meditation technique to reduce symptoms of Attention Deficit Hyperactivity Disorder (ADHD) by reducing stress and anxiety: An exploratory study. Current Issues in Education [On-line], 10(2). Available: http://cie.ed.asu.edu/volume10/number2/
Meditation speeds the mind's return after distraction
Another study comparing brain activity in experienced meditators and novices has looked at what happens when people meditating were interrupted by stimuli designed to mimic the appearance of spontaneous thoughts. The study compared 12 people with more than three years of daily practice in Zen meditation with 12 others who had never practiced meditation. It was found that, after interruption, experienced meditators were able to bring activity in most regions of the default mode network (especially the angular gyrus, a region important for processing language) back to baseline faster than non-meditators. The default mode network is associated with the occurrence of spontaneous thoughts and mind-wandering during wakeful rest. The findings indicate not only the attentional benefits of meditation, but also suggest a value for disorders characterized by excessive rumination or an abnormal production of task-unrelated thoughts, such as obsessive-compulsive disorder, anxiety disorder and major depression.
 “Thinking about Not-Thinking”: Neural Correlates of Conceptual Processing during Zen Meditation. PLoS ONE. 3(9), e3083 - e3083.(2008).
Improved attention with mindfulness training
More evidence of the benefits of meditation for attention comes from a study looking at the performance of novices taking part in an eight-week course that included up to 30 minutes of daily meditation, and experienced meditators who attended an intensive full-time, one-month retreat. Initially, the experienced participants demonstrated better executive functioning skills, the cognitive ability to voluntarily focus, manage tasks and prioritize goals. After the eight-week training, the novices had improved their ability to quickly and accurately move and focus attention, while the experienced participants, after their one-month intensive retreat, also improved their ability to keep attention "at the ready."
 Mindfulness training modifies subsystems of attention. Cognitive, Affective & Behavioral Neuroscience. 7(2), 109 - 119.(2007).
Brain scans show how meditation affects the brain
An imaging study comparing novice and experienced meditators found that experienced meditators showed greater activity in brain circuits involved in paying attention. But the most experienced meditators with at least 40,000 hours of experience showed a brief increase in activity as they started meditating, and then a drop to baseline, as if they were able to concentrate in an effortless way. Moreover, while the subjects meditated inside the MRI, the researchers periodically blasted them with disturbing noises. Among the experienced meditators, the noise had less effect on the brain areas involved in emotion and decision-making than among novice meditators. Among meditators with more than 40,000 hours of lifetime practice, these areas were hardly affected at all. The attention circuits affected by meditation are also involved in attention deficit hyperactivity disorder.
 Neural correlates of attentional expertise in long-term meditation practitioners. Proceedings of the National Academy of Sciences. 104(27), 11483 - 11488.(2007).
Meditation may improve attentional control
Paying attention to one thing can keep you from noticing something else. When people are shown two visual signals half a second apart, they often miss the second one — this effect is called the attentional blink. In a study involving 40 participants being trained in Vipassana meditation (designed to reduce mental distraction and improve sensory awareness), one group of 17 attended a 3 month retreat during which they meditated for 10–12 hours a day (practitioner group), and 23 simply received a 1-hour meditation class and were asked to meditate for 20 minutes daily for 1 week prior to each testing session (control group). The three months of intense training resulted in a smaller attentional blink and reduced brain activity to the first target (which was still detected with the same level of accuracy. Individuals with the most reduction in activity generally showed the most reduction in attentional blink size. The study demonstrates that mental training can result in increased attentional control.
 Mental Training Affects Distribution of Limited Brain Resources. PLoS Biol. 5(6), e138 - e138.(2007).
Full text available at http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.0050138
Meditation skills of Buddhist monks yield clues to brain's regulation of attention
Recent research has suggested that skilled meditation can alter certain aspects of the brain's neural activity. A new study has now found evidence that certain types of trained meditative practice can influence the conscious experience of visual perceptual rivalry, a phenomenon thought to involve brain mechanisms that regulate attention and conscious awareness. Perceptual rivalry arises normally when two different images are presented to each eye, and it is manifested as a fluctuation in the "dominant" image that is consciously perceived. The study involved 76 Tibetan Buddhist monks with training ranging from 5 to 54 years. Tested during the practice of two types of meditation: a "compassion"-oriented meditation (contemplation of suffering within the world), and "one-point" meditation (involving the maintained focus of attention on a single object or thought). Major increases in the durations of perceptual dominance were experienced by monks practicing one-point meditation, but not during compassion-oriented meditation. Additionally, under normal conditions the monks showed longer stable perception (average 4.1 seconds compared to 2.6 seconds for meditation-naïve control subjects). The findings suggest that processes particularly associated with one-point meditation can considerably alter the normal fluctuations in conscious state that are induced by perceptual rivalry.
 Meditation alters perceptual rivalry in Tibetan Buddhist monks. Current Biology. 15(11), R412-R413 - R412-R413.(2005).