A deep-learning-based explainable consciousness indicator (ECI) uses EEG responses to transcranial magnetic stimulation and resting-state EEG to separately quantify arousal and awareness. Tested during sleep (n=6), general anesthesia (n=16), and severe brain injury (n=34), ECI distinguishes states such as ketamine-induced anesthesia and rapid eye movement sleep, which combine low arousal with high awareness. Parietal brain regions are most relevant for these measurements. The indicator offers a way to disentangle the two components of consciousness across physiological, pharmacological, and pathological conditions.
A single highly trained expert in cognitive trance—a self-induced, focused state of consciousness—underwent transcranial magnetic stimulation combined with electroencephalography during normal wakefulness and during trance. The trance state was induced using a standardized protocol of body movements and vocalizations. Compared to resting wakefulness, the electrical reactivity of cortical circuits to magnetic pulses changed during trance, with differences measured across frontal and parietal brain areas. The findings suggest that cognitive trance alters the brain's electrical responses to external perturbations, offering insight into the neurophysiology of this state.