Saturday, April 9, 2011

Meditation and the Neuroplasticity of the Brain

Rick Hanson, Ph.D.
In a world that is quite obviously "on the edge of the sword," says contemplative neuropsychologist Dr. Rick Hanson, "(p)eople are way too driven by greed, hatred, and delusions," the 'three poisons' identified by the  Buddha. Worse, yet, Hanson observes: "Our caveman brains are armed with nuclear weapons."

Hanson, who holds a doctorate in neuropsychology and is co-author (with Richard Mendius, MD) of "Buddha's Brain: The Practical Neuroscience of Happiness, Love and Wisdom," is, however, quick to assure us that all is not lost. Far from it.

Due to the neuroplasticity of the brain - the brain's ability to grow and continually form new neural connections throughout an individual's lifetime - Hanson notes, our ability to exercise "neural networks of happiness, love and wisdom" may be precisely the saving grace that takes us out from under the existential 'Sword of Damocles' that seems to loom so large over our lives at times.

"Neuroplasticity (also known as cortical remapping)
refers to the ability of the brain to change as a result
of one's experience." (Source: Wikipedia)
It is only in the past several decades - during which time our knowledge of the brain increased a hundred-fold, according to Hanson - that neurologists and neuropsychologists have examined the ability of the adult brain to make new neural connections, an ability that may stay with us well into our 'golden years'. Prior to the 1990s, brain-wise, it was widely felt that it was all downhill after age 20-or-so.

Now, Hanson remarks, research amongst so-called 'contemplatives' (primarily seasoned Buddhist and Transcendental Meditation practitioners) has shown that the brain changes significantly as a result of prolonged meditative practice.
"One of the enduring changes in the brain of those who routinely meditate," Hanson notes, "is that the brain becomes thicker. In other words, those who routinely meditate build synapses, synaptic networks, and layers of capillaries (the tiny blood vessels that bring metabolic supplies such as glucose or oxygen to busy regions), which an MRI shows is measurably thicker in two major regions of the brain. One is in the pre-frontal cortex, located right behind the forehead. It’s involved in the executive control of attention – of deliberately paying attention to something. This change makes sense because that’s what you're doing when you meditate or engage in a contemplative activity."

"The second brain area that gets bigger," he further notes, "is a very important part called the insula. The insula tracks both the interior state of the body and the feelings of other people, which is fundamental to empathy. So, people who routinely tune into their own bodies – through some kind of mindfulness practice – make their insula thicker, which helps them become more self-aware and empathic. This is a good illustration of neuroplasticity, which is the idea that as the mind changes, the brain changes, or as Canadian psychologist Donald Hebb put it, neurons that fire together wire together."
"Buddhism teaches that the mind takes the shape of whatever it rests upon," Hanson notes; "or, more exactly, the brain takes the shape of whatever the mind rests upon."

Because of its neuroplasticity, Hanson posits, prolonged meditative practice with happiness and compassion as its objects will breed evermore happiness and compassion, and through this we may find the necessary escape from the Buddha's "three poisons." Meditative practice that trains the mind of the comtemplative towards ever greater compassion and happiness, due to the brain's plasticity, therefore breeds a repetitive and positive cycle leading towards enlightenment, just as the Buddha taught 2,500 years ago.

Science, it seems, at least Hanson's rapidly growing scientific discipline of contemplative neuroanatomy and neurospychology, is catching up with the evidence garnered from the world's oldest wisdom traditions. And, in this field at least, mind science is starting to pick up "the gauntlet thrown down by William James" over a century ago now. Hanson's research, along with the innovative research of many others in this growing filed, it seems, is starting to probe just what 'consciousness' is, and how higher states of consciousness forge not just our mental 'reality,' but also how they shape our physical 'reality' as well.

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