Question

scientists first began to understand how drugs work on the brain with what discovery?
(1 point)

opium dens
heroin withdrawal
opiate receptors
endorphins

Explanation:

The discovery of opiate receptors in the brain was a foundational breakthrough that allowed scientists to first comprehend how drugs interact with the brain at a molecular and cellular level, explaining the mechanism of opiate drugs' effects.

Answer:

Opiate receptors