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bioRxiv · 10.1101/2024.11.29.626048

Integrated phenomenology and brain connectivity demonstrate changes in nonlinear processing in jhana advanced meditation

Potash, R. M.·van Mil, S. D.·Estarellas, M.·Canales-Johnson, A.·Sacchet, M. D.
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Abstract

We present a neurophenomenological case study investigating distinct neural connectivity regimes during an advanced concentrative absorption meditation called jhana (ACAM-J),characterized by highly-stable attention and mental absorption. Using EEG recordings and phenomenological ratings (29 sessions) from a meditator with +20,000 hours of practice, we evaluated connectivity metrics tracking distinct large-scale neural interactions: nonlinear (WSMI and Directed Information), capturing non-oscillatory dynamics; and linear (WPLI) connectivity metrics, capturing oscillatory synchrony. Results demonstrate ACAM-J are better distinguished by non-oscillatory compared to oscillatory dynamics across multiple frequency ranges. Furthermore, combining attention-related phenomenological ratings with WSMI improves Bayesian decoding of ACAM-J compared to neural metrics alone. Crucially, deeper ACAM-J indicate an equalization of feedback and feedforward processes, suggesting a balance of internally- and externally-driven information processing. The results from this intensively sampled case study are a promising initial step in revealing the distinct neural dynamics during ACAM-J, offering insights into refined conscious states and highlighting the value of nonlinear neurophenomenological approaches to studying attentional states.

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Potash, R. M., van Mil, S. D., Estarellas, M., Canales-Johnson, A., Sacchet, M. D.. 2024-12-02. Integrated phenomenology and brain connectivity demonstrate changes in nonlinear processing in jhana advanced meditation. https://doi.org/10.1101/2024.11.29.626048

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