3510 Hersenen en meditatie
The unique brain anatomy of
alterations in cortical gyrification
Eileen Luders1*, Florian Kurth2, Emeran A. Mayer2, Arthur W. Toga1*, Katherine L. Narr1 and Christian Gaser3,4
Several cortical regions are reported to vary in meditation practitioners. However, prior analyses have focused primarily on examining gray matter or cortical thickness. Thus, additional effects with respect to other cortical features might have remained undetected. Gyrification (the pattern and degree of cortical folding) is an important cerebral characteristic related to the geometry of the brains surface. Thus, exploring cortical gyrification in long-term meditators may provide additional clues with respect to the underlying anatomical correlates of meditation. This study examined cortical gyrification in a large sample (n = 100) of meditators and controls, carefully matched for sex and age. Cortical gyrification was established by calculating mean curvature across thousands of vertices on individual cortical surface models. Pronounced group differences indicating larger gyrification in meditators were evident within the left precentral gyrus, right fusiform gyrus, right cuneus, as well as left and right anterior dorsal insula (the latter representing the global significance maximum). Positive correlations between gyrification and the number of meditation years were similarly pronounced in the right anterior dorsal insula. Although the exact functional implications of larger cortical gyrification remain to be established, these findings suggest the insula to be a key structure involved in aspects of meditation. For example, variations in insular complexity could affect the regulation of well-known distractions in the process of meditation, such as daydreaming, mind-wandering, and projections into past or future. Moreover, given that meditators are masters in introspection, awareness, and emotional control, increased insular gyrification may reflect an integration of autonomic, affective, and cognitive processes. Due to the cross-sectional nature of this study, further research is necessary to determine the relative contribution of nature and nurture to links between cortical gyrification and meditation.
- 1 Laboratory of Neuro Imaging, Department of Neurology, UCLA School of Medicine, Los Angeles, CA, USA
- 2 Department of Medicine, Center for Neurobiology of Stress, UCLA School of Medicine, Los Angeles, CA, USA
- 3 Department of Psychiatry, University of Jena, Jena, Germany
- 4 Department of Neurology, University of Jena, Jena, Germany
Keywords: brain, cortical complexity, curvature, folding, insula, meditation, mindfulness, MRI
Citation: Luders E, Kurth F, Mayer EA, Toga AW, Narr KL and Gaser C (2012) The unique brain anatomy of meditation practitioners: alterations in cortical gyrification. Front. Hum. Neurosci. 6:34. doi: 10.3389/fnhum.2012.00034
Received: 09 November 2011; Accepted: 14 February 2012; Published online: 29 February 2012.
Amishi P. Jha, University of Miami, USA
Lutz Jäncke, University of Zurich, Switzerland
Donna R. Roberts, Medical University of South Carolina, USA
Copyright: © 2012 Luders, Kurth, Mayer, Toga, Narr and Gaser. This is an open-access article distributed under the terms of the Creative Commons Attribution Non Commercial License, which permits non-commercial use, distribution, and reproduction in other forums, provided the original authors and source are credited.
*Correspondence: Eileen Luders and Arthur W. Toga, Laboratory of Neuro Imaging, Department of Neurology, UCLA School of Medicine, 635 Charles Young Drive South, Suite 225, Los Angeles, CA 90095-7334, USA. e-mail: firstname.lastname@example.org; email@example.com
David Spector It is very interesting to see such a close connection between mind and body over such a long period of time. The study is impressive for the care with which it measured brain sulci and gyri and for its analysis in which it showed good correlation of its results with previously reported results, which had a lesser degree of spatial resolution.
It is clear that this study looked at practitioners of a variety of types of meditation (mindfulness, Samatha, Vipassana, Raja Yoga, kriya, Dzogchen), but these types probably involved a related set of Buddhist and Hindu techniques of concentration and contemplation. The study seems to have followed a current research tradition in lumping these forms of meditation together and in ignoring the very different technique of transcending. This research tradition does not present a rationale for including certain types of meditation and ignoring others. Such a rationale is needed to explain what otherwise appears to be a random limitation of the research.
Transcending, the one form of meditation which appears to be often ignored when lumping together various forms of meditation, has been shown to be quite different in technique and physiological correlates from other forms of meditation. In addition, those who practice transcending report extensive beneficial changes in daily life, quickly, as a result of dissolving stored stresses efficiently. I think, for example, of the 40 subjects I recently measured who individually demonstrated a significant and steep drop in both state and trait anxiety after just two weeks of practicing transcending for fifteen minutes twice a day.
The two main independent sources of instruction in practicing transcending are Transcendental Meditation (TM) and Natural Stress Relief (NSR). They teach transcending in different ways, but both have extensive validation through many independent research studies. Both are interested in cooperating with researchers.
A future study comparing physical, physiological, mental, and psychological results of meditation practices similar to mindfulness, with meditation practices similar to Transcendental Meditation would be of great interest to establish objectively whether all meditation practices are of equal benefit or not. There is no a priori "obvious" objective answer based on either principles or practice.
The research framework to perform such studies or metastudies is clearly in place. Just consider the studies referenced in this paper along with the hundreds of studies conducted on practitioners of Transcendental Meditation since 1970.
Of course, the specific idea of measuring the gyrification of white matter is a new one. But there are many other correlates or results of practicing meditation that imply benefits.
All that is lacking is a single researcher having the interest in examining and comparing both of these meditation research traditions. This would mark the beginning of a new era in the comprehensive evaluation of the results of various forms of meditation. Such research would be of great benefit to the world.
Natural Stress Relief/USA