Inhaled DMT, a classic psychedelic, produces brief but profound changes in consciousness that vary with context. Using wireless EEG and source imaging, researchers mapped changes in neural oscillations. Frontal and temporal theta power inversely correlated with feelings of unity and transcendence—hallmarks of mystical-type experiences. A machine learning model confirmed the robustness of these results. The findings align with the idea that pre-drug mindset influences subjective experience. Priming individuals to lower theta power before taking a serotonergic psychedelic might increase the likelihood of mystical-type experiences, potentially enhancing well-being and therapeutic outcomes.
The laws of physics are time-symmetric, but dissipative systems like the brain show a preferred temporal direction. Using a deep learning framework inspired by stochastic thermodynamics, researchers analyzed electrocorticography signals from non-human primates. Brain activity during conscious wakefulness could be distinguished from its time-reversed version with high accuracy, using both frequency and phase information. This ability was reduced during deep sleep and ketamine-induced anesthesia. Transitions between slow (≈20 Hz) and fast frequencies (> 40 Hz) mainly contributed to the temporal asymmetry seen during wakefulness. The findings suggest that a preferred temporal direction in neural activity correlates with conscious awareness, linking brain processes to the subjective experience of time's passage.