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Biophoton emission from human palm during meditation: a multi‐method complexity analysis

E. Pace, L. de Paolis, G. Felici, I. Vaglini, M. Sandrini, M. Pettini, Angelo Gemignani, M. Benfatto

Frontiers in Photobiology October 22, 2026 DOI: 10.3389/fphbi.2026.1892522 (opens in new tab)

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Study at a glance

AI-extracted from the abstract
Characteristics Case study Case report Peer reviewed
Sample size 1
Population Right palm of a single human subject
Duration Three sessions on different days, each with four consecutive 15-minute phases
Measures Fano factor, skewness, right- and left-tail Expected Shortfall, multiscale Fano factor, Allan deviation, stripe-filtered Diffusion Entropy Analysis (DEA), Rényi entropy, Time Reversal test
Topics Meditation
Key findings The authors report a systematic reduction of emission intermittency during Sama Vritti box-breathing meditation, detected consistently across all three sessions. Diffusion entropy analysis placed the emission in a non-ergodic renewal regime (δ > 0.5, μ ≈ 2.5–2.9), with a pre-to-meditation decrease in δ approaching overall significance (Stouffer p ≈ 0.055). Rényi analysis showed reduced marginal amplitude burstiness and increased sequential pattern structure, which the authors interpret as entrainment to the breathing rhythm.

Abstract

Biophotons are ultra-weak photon emissions in the visible spectrum produced by living organisms. While extensively studied in plants, germinating seeds, and cell cultures, in vivo measurements on the human body remain relatively rare, and no systematic multi-method complexity analysis of human ultraweak photon emission (UPE) under controlled physiological modulation has been reported to date. We address this gap by developing and applying a comprehensive analytical framework to UPE measurements from the right palm of a human subject. Three independent sessions were conducted on different days, each comprising four consecutive 15-min phases: a Dark reference, a pre-meditation resting state (Pre), a structured meditation phase based on the Sama Vritti box-breathing protocol, and a post-meditation recovery (Post). The photon count series are analysed with four complementary methods targeting distinct aspects of the emission dynamics: distributional statistics (Fano factor, skewness, right- and left-tail Expected Shortfall); multiscale Fano factor and Allan deviation; stripe-filtered Diffusion Entropy Analysis (DEA); and Rényi entropy with a Time Reversal test. A central finding of this methodological study is that the different methods have complementary sensitivities, jointly converging on a coherent picture: a systematic reduction of emission intermittency during the meditative phase, consistently detected across all three sessions. The stripe-filtered DEA places the biological emission in the non-ergodic renewal regime ( δ > 0.5 , μ ≈ 2.5 –2.9), consistent with previous findings on cell cultures and germinating seeds, with a Pre → Meditation decrease of δ approaching overall significance (Stouffer p ≈ 0.055 ). The Rényi analysis reveals two distinct effects: a reduction of marginal amplitude burstiness ( T d i r ) and a simultaneous increase of sequential pattern structure ( T s e q ) , the latter interpreted as entrainment of the emission dynamics to the Sama Vritti breathing rhythm. These findings are consistent with the dynamical transitions reported in cardiac complexity during meditation by Tuladhar et al. via DEA of heart rate variability, and with the EEG reorganisation during Sama Vritti breathing reported by Zaccaro et al. in a cohort of experienced meditators, suggesting a coordinated multi-channel physiological response. The results establish an analytical framework for the complexity analysis of human UPE under physiological modulation and identify the most sensitive analytical observables for future multi-subject studies. The study is based on a single subject measured over three sessions, so that these findings are preliminary and require confirmation on a larger sample. Its purpose is to establish the feasibility of the measurement and to identify which analytical observables respond to a physiological transition. That the transitions detected here agree in direction with those reported by Tuladhar et al. and Zaccaro et al. on independent physiological channels is what gives them weight beyond the single case.

Comparable studies

Other case reports and case series on meditation, most cited first.

Study Year Design Participants
Brain sources of EEG gamma frequency during volitionally meditation-induced, altered states of consciousness, and experience of the self Advanced meditator 2001 Case study n = 1
Mindfulness Meditation for Alcohol Relapse Prevention: A Feasibility Pilot Study Adult alcohol-dependent graduates of an intensive outpatient program 2008 Prospective case series n = 19
How does it feel to lack a sense of boundaries? A case study of a long-term mindfulness meditator. A single long-term mindfulness practitioner (S) with 40 years of practice in... 2015 Qualitative case study n = 1
Loving‐kindness meditation to enhance recovery from negative symptoms of schizophrenia Individuals suffering from schizophrenia-spectrum disorders with persistent negative... 2009 Case study
Mindfulness-Based Cognitive Therapy for Problem Gambling A female problem gambler 2011 Case study n = 1

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