Meditative absorption shifts brain dynamics toward criticality

Criticality describes a regime between order and chaos that supports flexible yet stable informationprocessing. Here we examine whether neural dynamics can be volitionally shifted towardcriticality through the self-regulation of attention. We examined ten experienced practitioners ofmeditation during a 10-day retreat, comparing refined states of meditative absorption, called the“jhānas”, to regular mindfulness of breathing. We collected electroencephalography (EEG) andphysiological data during these practices and quantified the signal’s dynamical properties usingLempel–Ziv complexity, signal entropy, chaoticity and long-range temporal correlations. Inaddition, we estimated perturbational sensitivity using a global auditory oddball mismatchnegativity (MMN) during meditation. Relative to mindfulness, jhāna was associated withpronounced self-reported sensory fading, slower respiration, higher neural signal diversity acrossmultiple measures, reduced chaoticity, and enhanced MMN amplitude over frontocentral sites.Spectral analyses showed a flatter aperiodic 1/f component and a frequency-specific reorganizationof long-range temporal correlations. Together, increased diversity with reduced chaoticity andheightened deviance detection indicate a shift toward a metastable, near-critical regime duringjhāna. We propose an overlap of the phenomenology of jhāna with minimal phenomenalexperiences in terms of progressive attenuation of sensory content with preserved tonic alertness.Accordingly, our findings suggest that criticality is a candidate neurophysiological marker of theabsorptive, minimal-content dimension of the minimal phenomenal experience.