Non-duality in brain and experience of advanced meditators-key role for intrinsic neural timescales.

Distinguishing between self (internal) and environment (external) is fundamental to human experience, yet mind-body traditions describe non-dual states where this boundary dissolves. However, the neural basis of non-duality remains underexplored. We investigate this in advanced and novice meditators from the Isha Yoga tradition and meditation-naïve controls using psychological scales and EEG-based intrinsic neural timescales (INT). Subjects perform breath-watching meditation (internal attention) and a cognitive task (external attention), allowing us to operationalize non-duality as reduced internal-external distinction. Key findings include: (a) advanced meditators report stronger non-dual experiences during breath-watching than novices and controls; (b) across participants, INTs are longer during internal than external attention; (c) advanced meditators show similar INT durations between internal and external attention; and (d) this reduced INT difference correlates with stronger reported non-dual experiences. These results suggest that similar duration of intrinsic neural timescales during internal and external attention may serve as a neural signature of non-duality.