ascending reticular activating system

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Related to ascending reticular activating system: reticular formation

ascending reticular activating system (ARAS) (·senˑ·ding r·tiˑ·ky·ler akˑ·t·vāˈ·ting sisˑ·tm),

n system that transmits messages to the limbic system and hypothalamus, triggers release of hormones and neurotransmitters, and facilitates functions such as learning, memory, and wakefulness.


progressing to higher levels, usually used in reference to the nervous system.

ascending colon dilation
dilation of the spiral or coiled colon in cattle, usually a part of torsion of the mesentery of the colon; characterized by acute abdominal pain and distended loops of intestine in the right flank.
ascending hemorrhagic myelomalacia
see progressive hemorrhagic myelomalacia.
ascending hematomyelia
see progressive hemorrhagic myelomalacia.
ascending reticular activating system
see reticular activating system.
ascending syndrome