Cerebral cortex activities regulated

The reticular formation is also located in the midbrain and brainstem. The reticular formation is comprised of a collection of neurons that extend from the reticular substance of the upper spinal cord through the midbrain and the thalamus. The reticular formation monitors and controls consciousness and is also important in regulating the amount of arousal or alertness in the cerebral cortex. Consequently, CNS drugs that affect the arousal state of the individual tend to exert their effects on the reticular formation. Sedative-hypnotics and general anesthetics tend to decrease activity in the reticular formation, whereas certain CNS stimulants (caffeine, amphetamines) may increase arousal through a stimulatory effect on reticular formation neurons. 

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