title: Vigilance--a concept and its neurophysiological and biochemical implications.
mesh_terms: D000818:Animals; D001143:Arousal / Q000502:physiology*; D001519:Behavior / Q000502:physiology; D004558:Electric Stimulation; D006801:Humans; D009424:Nervous System Physiological Phenomena; D018377:Neurotransmitter Agents / Q000502:physiology
chemical_list: D018377:Neurotransmitter Agents