Which neurotransmitter level is boosted by both amphetamine and cocaine?

The correct answer is dopamine, as both amphetamine and cocaine have a significant impact on its levels in the brain. These substances are known to enhance the release of dopamine or inhibit its reuptake, leading to increased concentrations in the synaptic cleft. Dopamine is a key neurotransmitter associated with the brain's reward system, influencing pleasure, motivation, and reinforcement of behaviors.

Amphetamine works by promoting the release of dopamine and other neurotransmitters, while also blocking their reuptake. Cocaine, on the other hand, primarily acts by blocking the reuptake of dopamine, which allows it to remain in the synaptic space longer and amplify its effects. The increase in dopamine activity contributes to the stimulating and euphoric effects often associated with these substances, making them highly addictive.

While serotonin, GABA, and norepinephrine play essential roles in the brain, they are not primarily affected in the same manner by these substances as dopamine is. Thus, a focus on dopamine provides a clear understanding of the pharmacological actions of amphetamine and cocaine, establishing it as the correct response to the question.