What distinguishes the state of non-duality from our ordinary perception of the world? New research suggests the answer may lie in how the brain organizes the flow of time within its own neural networks.
At the NIMHANS neurophysiology laboratory in Bengaluru, seasoned Isha Yoga practitioners performed two distinct tasks: first observing their breath with inward-focused attention, and then completing a visual task requiring attention to external stimuli. During the experiment, scientists recorded brain activity using electroencephalography.
The study, published in the journal Communications Biology in June 2026, revealed an intriguing pattern. Among novices and control group participants, internal neural timescales were longer during breath observation and shorter when performing the external task. In experienced meditators, however, this discrepancy almost entirely vanished.
To assess the temporal organization of brain activity, researchers used the autocorrelation window (ACW) index, which reflects how long a neural system retains information from its previous states. This specific metric was found to be similar for both internally and externally directed attention among the most advanced practitioners.
The study’s authors—Mallipeddi Saket and colleagues from NIMHANS, the University of Ottawa, and the University of Liège—also found that the degree of this timescale convergence correlated with subjective ratings of non-dual experience. These results were replicated in an independent sample of experts, reinforcing the reliability of the findings.
The brain typically processes internal experiences and external events in different temporal modes. These new data show that this distinction becomes significantly less pronounced in long-term meditation practitioners. It is possible that this specific feature of neural dynamics is linked to the sense of unified experience often reported by those who practice non-dual forms of meditation.
Consider an orchestra where different sections play at their own individual tempos. Eventually, the rhythms begin to synchronize, and the music is perceived as a single, continuous flow. Something similar may occur within the brain when the differences between internally and externally oriented processes become less noticeable.
The authors emphasize that the discovered correlations do not prove a cause-and-effect relationship. Furthermore, the study did not compare non-dual meditation with other meditative practices and included a relatively small number of participants.
Nonetheless, the work points toward a potential neural marker for the non-dual state of consciousness. Should future research confirm these results, they could help us better understand how the brain constructs a sense of a separate "self" and why the boundary between internal and external is perceived differently in certain altered states of consciousness.
