- is a covalent compound stimulates the pleasure areas in our brain making us feel good ,speed up the activity in brain and keep us awake

Dopamine

Explanation:

The correct answer would be dopamine.

Dopamine is a chemical messenger produced in the substantia nigra, ventral tegmental area, and hypothalamus of the brain and has a variety of functions, including mediation of pleasure, learning, movements, sleep, etc.

Dopamine is released by the brain during pleasurable situations. The compound also has the ability to inhibit the actions of norepinephrine to make one feels alert and speeds up the activity in the brain.

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