Neurological Changes In Restorative-Yin Yoga Practice

From Tomio Hirai, Zen Meditation And Psychotherapy,

NY: Japan Publications, 1989, pp. 37-39 [markings, Kinseth]

THE QUIETNESS AND calmness of body-mind practices changes brain activity.  Above, EEG monitoring illustrates shifts in brain-wave patterns in intensive meditation.  These shifts require a change in brain chemistry—in neurotransmitters.  Clinical research demonstrates that meditation-based intervention may effectively reduce problematic symptoms, ongoing response to stress, and can accesses long-term memory or “storehouse consciousness” [Harai, p. 99], particularly with regard to repressed information in post-traumatic stress [e.g., search article by Peniston and Kulkosky on Vietnam veterans (1991)].  As a point of entry or meditation/biofeedback research, search E. E. Green or E. G. Peniston and P. J. Kulkosky or J. Kabit-Zinn or S. L. Farion and P. A. Norris or P. A. Norris or J. V. Basajian or L. Femhi and F. Selzer.

The stillness of restorative-yin practice induces changes in brain activity that interact in a “symphony” of integrated body physiology such as endocrine, respiratory, parasympathetic relaxation of heart rate and blood pressure, and muscle relaxation.  A very profound state, as expressed by the presence of theta brain-wave trains might be produced in intensive creativity, daydreaming, dreaming, but they remain largely the domain of intensive meditation or perhaps shamanic practices when sustained.  In restorative-yin practice, brain activity may not attain the sustained deep state of theta wave-train production that is does in meditation.  However, the attainment of theta production may occur in restorative practice by seasoned participants in extended restorative sessions that may occur in retreats.  The attainment of theta represents a quantum shift in states of consciousness. 

Within a restorative-yin practice session, de-stressing physiological changes are likely to occur, and this is remarkable and not to be discounted.  And when poses are held longer, there is the possibility for the left visual cortex to move to theta and produce hypnagogic imagery with more free association and less distortion [i.e., less subject to interpretation and checking].  This quality might facilitate access not only to early memory but also participant reports of a shift to a sense of “who you are” rather than a more culturally prescribed sense of “who you think you are.”  Still, in yoga, there has always been general agreement that the deepest states of consciousness are likely to be produced in meditation and possibly in savasana, but not in the various poses of yoga.  In fact, the variety of poses in yoga are often described as essential precursors—as preparation, training—for strong meditation that might eventually offer Samadhi.

As a body-mind practice, the stillness of restorative-yin yoga may surpass the quietness and calmness of practices such as tai chi and qigong.  By becoming still, restorative-yin yoga may provide a more profound sense of relaxation—producing deeper alpha states and, in some cases, theta states.  And like the impact of meditation training, regular practice of restorative-yin yoga will likely carry over into everyday life, producing a lower state of arousal or excitatory level or lessened reactivity to stress.  A person may still experience stress or even anger, but to a lesser degree.  In biofeedback/meditation training groups, beta-endorphin levels in normal waking states are lowered following perhaps ten training sessions, and lowering these beta-endorphin levels contribute to a decrease in electric activity [e.g., Peniston & Kulkowsky (1989). Alpha-theta brainwave training and beta-endorphin levels in alcoholics. Alcoholism: Clinical & Experimental Research, 13, 271-279]. 

Another way to look at possible neuro-effects of body-mind practice is the more recent use of functional magnetic resonance imaging (MRI) and positron emission tomography (PET) machines to visually illustrate the most active areas of the brain.  Specific actions and physical disorders may result in decreased and increased activity in various areas of the brain.  In mediation, the ability to attend to strong sensations without reacting strongly may show increased activity, for example, in a part of the right prefrontal cortex as well as the amygdala.

Going further, the “mind” of body-mind practices no longer exclusively reference the brain.  Physiologically, there are dimensions such as non-neurological “cell memory” as well as experiences that are categorized as “spirit” or “being” [as distinguished from “self” and “personality”] that may intuitively sense “mind” to be something that is not exclusively internal.  For example, describing a “neurobiology of we,” Daniel Siegel suggests that interpersonal behaviors influence neurobiology.  Physiologically, there may be a web of “mirror neurons” that fire in interpersonal communication.  Quite speculatively, on an MRI, deep care for another person might be measured in both persons as synchronized, mutual.  Ultimately, “mind” might eventually be likened to an ecological web in which our brain participates—metaphorically, like a computer in a network—as a component rather than autonomously, and with a degree of sophistication we have yet to imagine.

Overall, just in terms of concrete physiological changes, changes in brain activity that occur in restorative-yin yoga clearly contribute to the body’s process of significant de-stressing or restorative features.  Brain activity changes in restorative-yin practice.  And attention to brain activity occurring in body-mind practice describes our limits more than it delineates the perimeters of the effect of such practice.  Increasing Western scientific measures of brain activity suggests complex neurological processes that are still understood only vaguely.  But what is clear is a sense that regular restorative-yin yoga practice is not a practice of “doing next-to-nothing for those who cannot do ‘real’ yoga,” and that it may be, in fact, that which Eastern perspectives have suggested: an astonishing gateway to far more than we have allowed ourselves to imagine.