The change in consciousness during meditation was recorded on an encephalogram

Australian, American and Dutch researchers reported that an experienced meditation practitioner registered a purposeful change in his consciousness using electroencephalography (EEG). The publication about this appeared in the journal Neuropsychologia. The authors' attention was drawn to the phenomenon of nirodhi (translated from the Pali language as "cessation", "suppression", "removal"; in English, it is usually translated as cessation), in which the practitioner is said to briefly lose consciousness, and when he or she returns, experiences significant changes in the thought process and perception. The object of the study was one of the authors - 51-year-old Daniel M. Ingram from the Emergent Phenomenology Research Consortium (EPRC), who at the time of the study practiced various forms of meditation for 26 years (total duration of more than 23 thousand hours).

The material for the paper consisted of 37 cases of nirodha that occurred in Ingram during 29 EEG sessions over a period of four months. Spectral analysis of the data demonstrated a large-scale decrease in alpha activity approximately 40 seconds before such an event, reaching a minimum immediately after the onset of the event. Region of interest (ROI) analysis showed that during the period preceding the nirodha, alpha activity decreases linearly in occipital and parietal brain regions. This is accompanied by a moderate increase in theta activity in central, parietal, and right temporal regions, with beta and delta waves remaining essentially unchanged. Comparing these data with EEG correlates of consciousness and high-level mental functioning allowed the authors to consider the results as an objective indicator that experienced meditation practitioners are able to arbitrarily modulate the state of their consciousness, and this deserves neurophysiological study.