Functional neuroanatomic depiction of the different arousal systems. Macro-arousals are associated with consciousness and can be responded to by behavioral regulation. Micro-arousals, on the contrary, although appearing in the EEG, are responded to by motor sub-vigilance (motor cortex) activity. Raphe nuclei and N. locus coeruleus as main centers of the asleep-awake regulation are integrated in the vegetative arousal reactions (respiratory, cardiovascular, sympathetic and catecholaminergic arousal reactions). Medulla and hypothalamus can be viewed as hub of all the different arousal reactions.