The Geometry of Conscious States: A Five-Dimensional Framework

Most existing measures of consciousness state reduce neural dynamics to a single number, and each tends to work well on one kind of state transition and poorly on others. We propose a five-dimensional framework in which conscious state is a position in a five-channel EEG space, and a state transition is a trajectory through that space with both a magnitude and a direction (the direction carrying information about how a brain left waking consciousness, not just how far). We test the framework on three EEG cohorts spanning two state transitions: natural sleep wake-to-N3 (n = 28), Cambridge propofol baseline-to-moderate sedation (n = 19), and a separate light-propofol paradigm (n = 19 to 20). The sleep and…