Non-invasive Electrophysiological Characterization of Distinctive Meditative States in a Yogi during Samaadhi

Although mechanistic studies on Yoga and meditation have demonstrated their efficacy over the past few decades, very few studies have focused on the Yogic state of <i>Samaadhi</i>, characterized by an ultimate state of peace and happiness. In this study, we probed electrophysiological correlates of <i>Samaadhi</i> in a Yogi par excellence. This research was conducted in the 1980s and is now being brought to the public domain. We characterized changes in muscle, cardiac, and brain electrical activity, as well as breathing during about 30 minutes of meditative <i>Samaadhi</i> using a multichannel polygraph system during two experiments in 1985 and 1988. Spectral analysis was carried out using computers in the late 1980s. During meditation, we observed a substantial reduction in breathing amplitude (to <5% of pre-meditation levels) and subjectively measured heartbeat and pulse amplitude. Cardiac electrical activity remained intact, but the data pointed to the possibility of a considerable reduction in cardiac mechanical activity. Muscle contractions were consistent and substantially higher. A unique pattern of alpha as well as beta activity was observed in frontal electroencephalogram (EEG) electrodes, and alpha activity with occasional beta activity was observed in occipital EEG electrodes. During an epoch of eyes open state (within the meditation phase), EEG patterns resembled a deep meditative state, such as high occipital alpha and beta activity and frontal beta activity, which is strange because occipital alpha activity typically vanishes with the eyes open. Taken together, we provide preliminary evidence for the electrophysiological correlates of <i>Samaadhi</i>. The patterns observed from multiple modalities, taken together, were unique and different from those typically seen in adults. They were distinct from the electrophysiological correlates of three typical states of consciousness (awake, dreaming, and sleeping). Further research with the latest technologies and analytical tools is required for a better mechanistic understanding of the state of <i>Samaadhi</i>.