Today neuroscientists are talking more and more about brain plasticity or neuroplasticity. The brain continually evolves in response to our experience, through the establishment of new neuronal connections, the strengthening of existing ones, and the creation of new neurons.(p. 187)
Experiments:
1. Fred Gage & colleagues (1999, 1997)at the Salk Institute in California studied the response of rats to an enriched environment: In 45 days the number of neurons in the hippocampus (a brain structure associated with processing novel experiences and dispatching them for storage in other areas of the brain) grew by 15%, even in older rats.
2. Peter Erickson (1998) in Sweden studied the formation of new neurons in cancer patients found that even in elderly patients' brains new neurons were formed in their hippocampus. (pp. 187-188)
3. Daniel Goleman (Destructive Emotions, 2003) reported that musical training offers an apt model for neuroplasticity. MRI studies found profound changes in the cognitive capacities involved in the pursuit of musicians, chess players, and Olympic athletes. (p. 188)
4. Richard Davidson and his team in the W.M.Keck Lab for Functional Brain Imaging and Behavior at UW-Madison (2003, 2004, 2005) studied long-term practice of meditation, even when carried out in the neutral environment of a hermitage, induced important and lasting changes in the brain. (pp. 189-201)
In the lab there are two main ways to test the meditators: electroencephalograms (EEG)to record changes in the brain's electrical activity, and functional magnetic resonance imaging (fMRI) to measure bood flow in various brain areas, and to provide precise localization of cerebral activity. (p.191)
Findings:
Striking differences between novices and expert meditators. During meditation on compassion, most experienced meditators showed a dramatic increase in the high-frequency brain activity called gamma waves, "of a sort that has never been reported before in the neuroscience literature," says Richard Davidson. Movement of the waves through the brain was far better coordinated, or synchronized, than in the controlled group, who showed only a slight increase in gamma wave activity while meditating.
This seems to demonstrate that "the brain is capable of being trained and physically modified in ways few people can imagine" and that the meditators are able deliberately to regulate their cerebral activity. (p. 191)
The monks who had spent the most years meditating generated the highest levels of gamma waves. This led Richard Davidson to speculate that "meditation not only changes the workings of the brain in the short term, but also quite possibly produces permanent changes." The fact "that monks with the most hours of meditation showed the greatest brain changes gives us confidence that the changes are actually produced by mental training," he adds (p. 192)
Emotions are complex phenomena that are functions of the interaction of several regions of the brain. Richard Davidson and his team found that those who report feeling joy, altruism, interest or enthusiasm present significant cerebral activity in the left prefrontal cortex. Those who predominantly experience negative emotional states as depression, pessimism, or anxiety manifest more activity in the right prefrontal cortex. These characteristics are relatively stable and manifest from early childhood.
Implications of these findings: "we each have a characteristic ratio of right-to-left activation in the prefrontal areas that offers a barometer of the moods we are likely to feel day to day....Each of us has the capacity to shift our moods, at least a bit, and to change this ratio. The further to the left the ratio tilts, the better our frame of mind tends to be..." Daniel Goleman (pp. 193-194)
Davidson's research also found that as the meditators began meditating on compassion, an extraordinary increase of left prefrontal activity was registered. This corroborates the research of psychologists showing that the most altruistic members of a population are also those who enjoy the highest sense of satisfaction in life. (p. 194)
Preliminary results obtained by Jonathan Cohen and Brent Field at Princeton University also suggest that trained meditators are able to sustain focused attention upon various tasks over a much longer period of time than untrained controls.
Ekman and Levenson's study about the startle response: The intensity of the startle response is known to reflect the predominance of the negative emotions to which someone is subject. Hundreds of subjects failed to repress the startle, and restrain their muscular spasms. Only the meditator was able to. "I was not actively trying to control the startle, but the detonation seemed weaker, as if I were hearing it from a distance....while in open presence you are resting in the present moment and the bang simply occurs and causes only a little disturbance, like a bird crossing the sky," says the meditator. This tells us that the body reacted...but the bang had no emotional impact on the mind. The meditator's performance suggests remarkable emotional equanimity that the ancient texts describe as one of the fruits of meditative practice. (pp.198-199)
Conclusions
The trained mind is physically different from the untrained one.Most of the meditators studied by Antoine Lutz and Richard Davidson have gone way beyond ten thousand hours of meditation. Studies by Richard Davidson and Jon Kabat-Zinn, B. Allan Wallace at Santa Barbara Institute for Consciousness Studies, and Paul Ekman (the Mind and Life Institute), and Margaret Kemeny at UC-San Francisco three-month meditation training courses also yield remarkable results.
If it is possible for meditators to train their minds to make their destructive emotions vanish, certain practical elements of that meditative training could be valuably incorporated into the education of children and help adults to achieve better quality of life. ...the current collaboration between scientists and comtemplatives could awaken people's interest to the immense value of mind training. (pp. 200-201)
Source:
Matthieu Ricard, Happiness: A Guide to Developing Life's Most Important Skill. Translated by Jesse Browner. (New York, NY: Little, Brown and Company, 2003).
