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Sit comfortably and pay attention to your breath as you inhale and exhale. When thoughts drift into your mind, just ignore them and stay focused on your breath. Seems simple enough, right? But it turns out that this basic practice, known as mindfulness meditation, is powerful stuff.Not only does it help reduce stress and improve mood, but it actually changes your brain structure. And those changes can be quite beneficial.How Meditation Changes the BrainSara Lazar is a neuroscientist at the Massachusetts Research Institute at Harvard University who studies meditations effect on the brain. Meditation-induced brain changes can be seen primarily in three areas of the brain, she explains: the posterior cingulate cortex (PCC), the hippocampus, and the amygdala.The PCC is involved in mind wandering and in ones sense of self. In long-term meditators, the PCC is quieter than in people who dont meditate, explains Lazar. Thats likely because sitting and focusing the breath trains the brain to pay attention to what you want it to pay attention to and reduces mind wandering.The hippocampus is involved in learning, memory, and executive control. In meditators, the structure of the hippocampus increases, explains Lazar.Who it talks to and how it talks to other brain regions seems to change with [meditation] practice, she says.Grey matter (mostly neurons and some support cells) in the hippocampus also increases in people who meditate. Grey matter processes information, but it needs help from white matter. White matter acts as a conductor of brain signals, Lazar explains, and meditation causes white matter in the hippocampus to increase as well.Meditation for Anxiety and DepressionWhile the hippocampus is bulking up, as Lazar puts it, and sending signals more rapidly, the amygdala is getting smaller and less active. Lazar describes the amygdala as being all about emotional reactivity, particularly fear.We see that it becomes less active during threatening conditions, she says.This might explain the well-documented effect of meditation on anxiety and depression. Many of these changes can be seen after as little as eight weeks of regular meditation practice.These changes in the brain, particularly the increase in grey matter, suggest that meditation could effectively postpone dementia. Lazar says that there is some evidence that meditation can lead to improvements in people with mild cognitive impairment, which can be a precursor to dementia.White matter also plays a role. In normal aging, as well as in dementia, white matter begins to deteriorate. Thats why at age 60, it can take even a healthy brain a little longer to figure things out than it did at age 20. Many lifestyle factors, including diet, can affect white matter. But meditation certainly helps preserve it.We can see white matter tracks changing and moving and getting bigger, says Lazar.Going Deep Inside the BrainMost previous research, like that done by Lazar, has used either magnetic resonance imaging (MRI) or electroencephalography (EEG) to get a picture of whats happening in the brain during meditation. Ignacio Saez, a neuroscientist at Icahn School of Medicine at Mount Sinai, took a different approach.In a study published in PNAS, Saez and colleagues recruited epilepsy patients who had previously had electrodes implanted in their brains. The purpose of the electrodes was to control seizures, but they also offer a unique window into the electrical activity of the brain at any given moment. The patients agreed to undergo guided meditation training, allowing Saez and his team to see far more than MRI or EEG can show.We were able to measure a voltage that reflects the coordinated activity of hundreds of thousands of neurons, right there in real time, he says.None of these people had meditated before. They were trained over the course of a year in Loving-Kindness Meditation, a method that focuses on developing feelings of kindness and compassion. Saez and his team found that meditation practice caused modulations in the beta and gamma waves in the amygdala and hippocampus of these novice meditators.Heightened beta waves in these areas, Saez points out, are usually correlated with undesirable mental states, such as depression and anxiety. Indeed, the patients reported that after meditation, and the resulting changes in beta and gamma waves, they felt better, and their anxiety was lower. One exciting thing about this research, says Saez, is that it shows that people can learn to control their neuronal responses themselves."You're willfully modulating your brain activity in this very specific way by engaging in these meditative practices that have been used for thousands of years," says Saez. "You can specifically change the one thing that potentially underlies bad mental states and bring it back to normal and feel better."The More You PracticeSo how much meditation practice does it take to see benefits? Though theres not yet a definitive answer, Lazar says that several studies have found correlations between practice time and changes in the brain.The more you practice, the more benefit you're gonna get, she says. If youre interested in giving meditation a try, Lazar recommends visiting the Insight Meditation Center online. It offers free online instruction, classes, and other support. You can also find an online guided Loving-Kindness Meditation here.Article SourcesOur writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:Frontiers In Psycology. Mechanisms of white matter change induced by meditation training Annals of the New York Academy of Sciences. The potential effects of meditation on age-related cognitive decline: a systematic reviewPubMed. Lazar SWAvery Hurt is a freelance science journalist. In addition to writing for Discover, she writes regularly for a variety of outlets, both print and online, including National Geographic, Science News Explores, Medscape, and WebMD. Shes the author of Bullet With Your Name on It: What You Will Probably Die From and What You Can Do About It, Clerisy Press 2007, as well as several books for young readers. Avery got her start in journalism while attending university, writing for the school newspaper and editing the student non-fiction magazine. Though she writes about all areas of science, she is particularly interested in neuroscience, the science of consciousness, and AIinterests she developed while earning a degree in philosophy.
