Experienced meditators tend to have a different pattern of brain activity compared to non-meditators during a cognitive test of impulsiveness and sustained attention, according to new research published in the journal PLOS One.
The findings provide new insights into the relationship between mindfulness meditation and mental health.
“I have worked in a psychiatry research centre for ten years now. We use brain stimulation techniques to treat depression that hasn’t responded to typical medication,” said study author Neil W. Bailey, a post-doctoral researcher at the Epworth Centre for Innovation in Mental Health.
“Seeing how ineffective treatments for depression can be (around 50% success rates are considered high) and how common depression has become, I became interested in whether there were methods for preventing it rather than treating it once people were already depressed. Mindfulness seems to be an excellent option.”
“Mindfulness can be used by almost anyone and learnt online, so could be applied across society. In particular, it has been demonstrated to be effective at improving both mental health and academic performance in schools. Interestingly, the gains in academic performance outweigh the time cost of practicing mindfulness. As such, implementing mindfulness in schools wouldn’t take away from other aspects of the curriculum,” Bailey said.
“In order to strengthen the case for implementing mindfulness in schools, our team has been focused on explaining how mindfulness leads to improved mental health and cognitive performance. The idea is that it is great for us to be able to say that something works, but it’s even more convincing to be able to say ‘it works, and here’s how.”
“Understanding the mechanism of action of an intervention also allows us to adjust the parameters of the intervention to more effectively target the mechanism of action. This leads to larger benefits for people undertaking the intervention.”
The researchers used electroencephalography (EEG) to compare the electrical brain activity of 34 meditators to 28 demographically-matched controls with no meditation experience. The meditators had all practiced meditation for at least two hours per week for six months, and the average length of meditation experience was 8 years.
During the brain monitoring study, the participants completed a computerized Go/No-go response inhibition task, which is a common test of attention and self-control. There was no significant difference in reaction times between the two groups. But the meditators tended to have more accurate responses, and the researchers also observed differences in brain activity.
“Our study suggests that the improved performance in our task was because experienced mindfulness meditators activated their frontal cortex more when they were completing the task. Activity in this area is related to attention and decision making, so this activity is likely to have helped them focus on the task (which involved deciding to quickly respond to one image flashed on a computer screen, while inhibiting the impulse to respond to another image,)” Bailey told PsyPost.
“Unexpectedly, the meditators also showed more activity in their right parietal lobe between 0 and 50 ms after the images were presented on the computer screen. This time period is before the information from the images even reaches the occipital lobe, where vision is processed.”
“Although it would be tempting to attribute this to something surreal (like precognition), the stimuli were presented at a predictable rate, so it appears that the meditators were preparing their right parietal lobe to process the visual information – they were anticipating the images more effectively than the non-meditators. As a result they could more accurately make the very quick decisions about whether to respond to the images or not,” Bailey explained.
But the study — like all research — includes some limitations.
“The study was cross-sectional in design, which means it compared healthy non-meditators to meditators who had been practicing for years, without testing them before they started practicing. This study design also does not have an active control group for comparison with the meditators (it would be very difficult to use an active control longitudinal study design including meditators with eight years of experience!)” Bailey said.
“Without an active control group, the interpretation of the study with the fewest assumptions is that the differences we found relate to ‘leading a life that involves meditation’ but does not suggest meditation is causal in the differences. However, other research using active control groups has shown that meditation causes changes in cognitive performance and brain activity.”
“The main caveat with all scientific research is that until the study is replicated, we can’t be sure the results weren’t just specific to the particular people who took part in the study. We’re actually almost finished collecting data for a replication of this study, so we’ll know soon!” Bailey added.
It is also unclear if the findings extend to less experienced meditators.
“The improvements in cognitive performance and the changes in brain activity are unlikely to be obtained from just ‘trying out’ mindfulness for a few weeks — although studies have shown improved cognitive performance and brain changes from short periods of practice, those changes are unlikely to be as strong as the changes found in our study,” Bailey said.
“More work needs to be done to determine how much mindfulness meditation practice is enough to obtain benefit, and what people can expect from different amounts of practice. In fact, as far as I’m aware, no experimental research has been able to answer the question ‘what’s the minimum amount of mindfulness required for improved mental health?’ This is an important question to answer, because until we know the answer, we can’t be sure that people practicing a small amount of mindfulness per day (for example ten minutes) aren’t just wasting their time.”
The findings suggest that meditation practice does not just enhance typical neural responses. It may change how the brain processes information..
“Previous research has shown that brain activity differs between people who perform well in cognitive tasks and people who don’t. This research has typically shown that the high performers activate the same brain regions that low performers activate, but generate higher voltages (more activity) in those regions,” Bailey explained.
“Our research seems to suggest this is not the case in meditators — sometimes they even show lower voltages (less activity). However, meditators do activate different brain regions. It seems that instead of generating more activity, they’re using a different strategy in order to perform better, sometimes while generating less activity (so their brains may be acting more efficiently rather than working harder.)”
“We wonder if this explains (at least in part) the improved mental health experienced by meditators – ‘responding to events with higher cognitive performance, while at the same time having brains that are working less’ certainly sounds like a less stressful, more peaceful way of going through the day,” Bailey concluded.
The study, “Mindfulness meditators show altered distributions of early and late neural activity markers of attention in a response inhibition task,” was authored by Neil W. Bailey, Gabrielle Freedman, Kavya Raj, Caley M. Sullivan, Nigel C. Rogasch, Sung W. Chung, Kate E. Hoy, Richard Chambers, Craig Hassed, Nicholas T. Van Dam, Thomas Koenig, and Paul B. Fitzgerald.
