Until not long ago, scientists studying the nervous system believed that the adult brain was incapable of growing new cells. That’s now known to be false. In fact new cells are being born in the brain all the time. If they’re needed (that is, if the part of the brain that they’re in is being used intensively) then those cells become wired in to the existing networks of nerves, and that part of the brain grows. On the other hand, if they’re not used, they’ll be reabsorbed.
Even without growing new cells, the brain is constantly developing and pruning connections, though. Every new memory you create, every thing you forget, every new piece of learning, changes the physical structure of your brain in a measurable way.
This ability of the brain to remodel itself is called “plasticity,” or “neuroplasticity.” That the brain physically grows in response to learning was first shown in the late 1700’s, but unfortunately that discovery was forgotten. Then, in the late 1990’s, it was found that London taxi drivers, who spend years memorizing the layout of the city’s streets, have enlargement of the hippocampus, which is a part of the brain involved in spatial navigation. Taxi drivers, it turned out, do not start out with an enlarged hippocampus, but develop this as a result of practicing their navigation skills.
In 2011, Sarah Lazar of Harvard found that after just eight weeks of meditation, there were observable increases in density in brain structures involved in learning and memory, emotional regulation, self-referential processing, empathy and compassion, and putting experiences into perspective. A later study by Lazar additionally showed shrinkage of the amygdala, which is involved in the fight or flight reflex. The change in the amygdala was correlated to a measurable reduction in stress levels.
It’s well-established that the brain’s cortex—the outer layer of the brain, which plays a key role in memory, attention, thought, language, and consciousness—shrinks as we get older, causing problems with slowed thinking and poorer memories. Lazar has found that regular meditators have a thicker cortex. In her studies she found 50-year-old meditators with the same amount of gray matter as 25-year-olds.
These findings are enormously encouraging, especially since they can be shown after an average of less than half an hour of meditation a day for just eight weeks. They have universal applicability: as far as I’m aware not a single participant in a neuroscience study has been found to have a brain that can’t change! Such a person, if they did exist, would be of enormous interest to scientists!
If we practice, the brain will change, and we will get better at regulating our emotions, become happier and calmer, and find ourselves less prone to anxiety and other unpleasant states. Isn’t that encouraging?
The brain, in its ability to grow, is like a muscle, and the practice of mindfulness—including, of course, meditation—is akin to physical exercise. Meditation practice helps the brain to be healthier and to work more effectively. It helps us to regulate our emotions and to avoid stress. And it slows the aging of the brain.
It’s wrong to think, though, that meditation only changes the brain. By changing the way that the brain functions, it promotes better physical health through reducing inflammation and by reducing the level of stress hormones circulating in the body. It reduces the perception of pain. It makes us feel calmer, more relaxed, and more in control of our lives. It also changes our emotional expression, bringing more emotional balance and greater optimism and positivity. All of these changes directly affect our lives, so that we’re more likely to experience support from others, rather than conflict. Meditation, in effect, changes our entire lives for the better, in a kind of positivity cascade.
In a course I’m leading, starting, March 1, we’ll learn about specific findings from science about the many ways in which we can benefit from meditation. We’ll also practically explore meditation, with at least 12 guided meditations I’ve recorded specially. This course, Optimize Your Brain: Awaken Your Full Potential With Meditation, is suitable for those who are new to meditation as well as to experienced meditators who want to expand their repertoire of skills and to give themselves a better understanding what’s happening in the brain and body when they sit.
Click here for more information on Optimize Your Brain: Awaken Your Full Potential With Meditation.
PBS Newshour: Before he was a personal physician to the Dalai Lama, Dr. Barry Kerzin never imagined that a professional trip to Tibet would lead him down a decades-long path studying Buddhism and meditation. Special correspondent Fred de Sam Lazaro talks to Kerzin in India about his feeling that compassion and empathy are essential to medical training.