Thursday, April 5, 2012

Meditation and the Brain


"As a single footstep will not make a path on the earth, so a single thought will not make a pathway in the mind. To make a deep physical path, we walk again and again. To make a deep mental path, we must think over and over the kind of thoughts we wish to dominate our lives."
 
                                                                  ~ Henry David Thoreau

Right now we find ourselves at a particularly prescient moment in the fields of medicine and psychology. A ‘tipping point’ instigated by the collision of the paradigms of Western science and Eastern mysticism.  Through this contemporary convergence of contemplative practices and neuroscience, scientists have been attempting to discover the complex mechanisms by which our brains can influence our biology. This has led to huge advances in our understanding of the effect that behavioral or 'mental interventions' can have upon the body. These studies of mind-body relations are no longer pseudo scientific ideals being espoused by alternative health care practitioners but are now becoming widely accepted in the mainstream scientific community. This field of study is known specifically as Contemplative Neuroscience and focuses on the physical and psychological changes in brain function and structure that are induced by contemplative practices such as Meditation and Yoga. Contemplative neuroscience is predicated by the large body of literature on Neuroplasticity. The term neuroplasticity refers to the ability of the brain to make changes in itself. It maintains that, “the brain is the key organ which is built to change in response to experience”. In this essay I will provide some brief examples of the many studies which have shown that contemplative practices can induce changes which endure our cognitive and emotional habits as well as the physical makeup of the brain. 
In 2007 a study called "Mindfulness meditation reveals distinct neural modes of self-reference" by a Norman Farb and his team at the University of Toronto broke new ground in our understanding of mindfulness from a scientific perspective. Through the study they were able to distinguish two distinct pathways within the brain, the Narrative Network and the Direct Experience network. The narrative network is the network involved in planning, daydreaming and ruminating, (basically when you are thinking about yourself and other people). This network is active during most of our waking moments and uses areas of the brain such as the Medial Prefrontal Cortex, along with memory regions such as the Hippocampus. They found that these regions were distinctly different from the areas of the brain which are activated under the Direct Experience Network, the network involved when you are not thinking intently about the past or future, other people, or yourself. Rather, you are experiencing information coming into your senses in present time. They noticed that areas such as the Insula (the only region in the brain which is specifically linked to the peripheral organs) and the Anterior Cingulate Cortex (which is a region central to switching your attention), were more active during periods of meditation. The Farb study showed us that there is a whole other way of experiencing experience and since then a series of other studies have found that these two circuits, Narrative and Direct Experience are seminal in our understandings of the effects of behavior upon the brain. 

Exponents of Buddhism have long considered that the brain and the heart are inextricably connected and that the heart is the source of the generation of compassion in the body. Richard J Davidson, professor of Psychiatry and Psychology at the University of Wisconsin Madison, is a multi award winning scientists and avid spiritual seeker who has been conducting extensive research on this brain / heart connection since the mid Nineties. He believes that; “There is no more effective way to produce specific changes in the brain than behavioral or mental interventions”It seems the 14th Dalai Lama also regards the importance of this research as he has supplied about a dozen Tibetan Buddhist monks to Dr Davidson and his team for extensive clinical research since 1996. The results of one particular study concluded that in the course of meditating for tens of thousands of hours, the monks had actually altered the structure and function of their brains. (Davidson, R.J. & Harrington A.) In a striking difference between expert and novice meditation practitioners, the former showed a dramatic increase in high frequency or Gamma waves in areas of the brain such as the the Insula and Right TPJ (which are both involved in the generation of compassion and regulation of emotions). The changes in the Insula were also strongly mirrored by cardiac changes which suggests that that is an important link between ‘neuro-cardiac coupling’ and meditation. Not only does this supply us with a model for a future alliance between Buddhism and science but also provides the scientific community with more incentive to regard studies of consciousness and meditation in a different light. 
Examples of how meditation as influences psychological changes are most notable in research conducted with chronically depressed patients where an 8 Week Mindfulness Based Therapy program (MBCT) of 2.5hrs a week proved to offer protection against  relapse/recurrence equal with that of antidepressant drugs.  (Segal ZV, et al. 2010)  
As noted earlier, the brain circuits transformed by meditation play a key role in not only changing our psychological perspectives but also positively affecting the body’s peripheral biological systems. In an 8-week Mindfulness Based Stress Reduction (MBCT) program carried out in a work environment on twenty five healthy employees, the researchers found that brain activity was altered and the level of change in brain activity predicted the level of increase in antibody response to an influenza vaccine. (Davidson RJ, Kabat-Zinn J, Schumacher J, et al, 2003). 


In a similar study MBCT was used to buffer the effects of psychological stress on the development of inflammation in the skin (Rosenkranz et al, 2003) Both these studies suggest that meditation can reduce stress induced immune responses and in effect have a significant impact upon our ability to recover from illnesses. 
The integrative convergence of ancient contemplative practices and neuroscience has opened up entrance for a new  paradigm to enter into the last refuges of our inner selves. The field of psychology seems to sit in this liminal space, while it is pulled into the mystery beyond the doorway of passage it is almost equally drawn the other way by the laws of old an Newtonian / Cartesian philosophy. In order for the current Western medical/ psychiatric model to make the next necessary leap into a new era it is important that we honor the synchronicity we are discovering in both overlapping fields and adopt a more integrative, humanistic angle in treating disease. The critical time is now. It is no longer necessary to define illness within the atomistic categories of pathology but to think in terms of the unique processes of the individual person. At the same time as we move forward, it is essential that studies of spiritual experience can incorporate rigorous scientific method so as to help the wider biomedical and psychological community understand and appreciate the importance of including spiritual qualities in medical care. It is my hope that through incorporating the mind back into medicine we may take more responsibility for our own health, and be lead further away from the pharmaceutical dependence in which our health care system currently resides.

Annotated Reference List
1. R.J Davidson. A. Lutz. “Buddha’s Brain: Neuroplasticity and Meditation” IEEE Signal Processing Magazine Jan 2008
2. Davidson, R.J. & Harrington, A. (Eds.). (2001). “Visions of compassion: Western scientists and Tibetan Buddhists examine human nature”. Oxford: Oxford Press.
3. Segal ZV, et al. (2010). Meditation As Good As Medication? Arch Gen Psychiatry, 67(12):1256–64.
4. Davidson RJ, Kabat-Zinn J, Schumacher J, et al. Alterations in brain and immune function produced by mindfulness meditation. Psychosom Med. 2003;65(4):564-570.
5. Rosenkranz, M. A., Jackson, D. C., Dalton, K. M., Dolski, I., Ryff, C. D., Singer, B. H.,
Muller, D., Kalin, N. H., & Davidson, R. J. (2003). “Affective style and in vivo
immune response: neurobehavioral mechanisms.” Proceedings of the National Academy of Sciences of the United States of America, 100 (19), 11148-11152.

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