Consciousness: A Neurological Perspective
Behavioural Neurology April 2, 2015 Andrea E. Cavanna, Sachin Shah, Clare M. Eddy et al.
A bidimensional model of consciousness, distinguishing level of arousal from subjective awareness, can differentiate healthy states (sleep stages, REM sleep) from altered states in neurological conditions (epilepsy, vegetative state, coma). Arousal and awareness are positively correlated in normal physiology except during REM sleep; disruption of this relationship characterizes vegetative state, minimally conscious state, complex partial seizures, and sleepwalking.