ABSTRACT

“Brain death” represents the loss of Information-Consciousness-Attention (ICA) arousal capabilities, and terminates the capability for information nutriment. Research on ICA arousal has emphasized different concepts, depending on which aspect of a behavior episode was emphasized. A minimal level of endogenously produced ICA arousal must exist before the brain will respond to external stimulation. The sleep-wakefulness cycle in humans is an ICA circadian rhythm. The normal lower boundary of generalized ICA arousal is deep sleep. Basic biological functions covary with different levels of arousal, increasing in variability as ICA arousal increases. Base rate ICA arousal must be present before specialized arousal functions can occur. When base rate ICA arousal exists, only some portion of the information-processing activities continuously occurring is subjectively experienced as the content of consciousness. Arousal of ICA information monitoring and collection has been examined most extensively. Generalized ICA arousal and selective attentional arousal interact in information monitoring and affect the content of consciousness.