Final answer:
Cocaine's effects are mainly due to blocking the removal of dopamine from the synapses, leading to increased stimulation of the brain's pleasure centers and resulting in its addictive properties.
Step-by-step explanation:
Cocaine's effects on the brain are primarily due to its ability to block the removal of dopamine from the synapses between neurons, leading to increased levels that stimulate the pleasure centers of the brain. This mechanism is responsible for the feelings of euphoria and addiction associated with the drug's use. The blocking of dopamine reuptake in the neuronal synapse accentuates dopamine action and is tied to the characteristic "high" as well as cocaine's addictive properties. Additionally, this process can leave the user with depleted dopamine levels shortly after use, often leading to cravings for more cocaine to restore the pleasurable feelings.