Neurobiology of Yoga Practice

Introduction

Self-knowledge and behavior training have been substantial parts of Yoga for many centuries. The neuroscience approach towards the effects of Yoga on cognition and brain function/structure is a relatively new field of research. As technology advances, new technical support is gained to investigate long ago experienced traditional Yoga practices. To the extent Yoga gains more supporters all over the world, many researchers become interested in unraveling the “mysteries” surrounding its techniques, and thus, creating connection and a contemporaneous approach for traditional Yoga through the modern understanding of science.

The role of a researcher is to methodically observe and describe phenomena. Similarly, the practice of yoga leads the practitioner to meticulously observe his/her thoughts and feelings. In the absence of instruments to explain such events, the sages of the past have explained some psychological and physiological phenomena based on myths, stories and symbols (Campbell, 1991). The definition of Yoga by Patanjali: “Yoga's citta vrtti nirodhah” (Yoga is the silencing of the modifications of the mind) can now be better understood from a neuroscientific perspective. In this ancient text, the author reveals the existence of obstacles (kleśāḥ) that prevent the human being from living a joyful life. The psychological distress caused by kleśāḥ is based on ignorance, which is understood in the philosophy of Yoga as confounding the Self with mental activity. In modern language, one could say that stress, depression and anxiety are some of these obstacles. Such obstacles affect circuitries in the central nervous system, which are strengthened at each and every access. The same way, specific components of yoga may positively influence cognitive, emotional, behavioral, and autonomic modulation of the human being, through an emphasis on interoception and bottom-up input, resulting in physical and psychological health, as well as through a top-down regulation during meditation, quieting mind and body. According to some authors, yoga is formed by a vast group of synergistic tools, which aim at integrating high and low-level brain systems, and creates a self-feeding process of afferent and re-afferent inputs, such as somatosensory, viscerosensory, and chemosensory ones (Gard, Noggle, Park, Vago, & Wilson, 2014a).