Comprehensive network of connections containing nerve cell bodies and fibers in the brain stem. Originating in the medulla oblogata and extending into the midbrain, it is integrated into the spinal cord, cerebellum, thalamus, and cerebral cortex. Provides regulation of arousal, alertness, and sleep-wake cycles, as well as operating a portion of posture and movement. Also known as: brain stem reticular formation. See also: reticular activating system.

RETICULAR FORMATION: "The reticular formation is connected to many structures in the brain."