Dopamine and Caffeine
Caffeine can increase the number of D2/D3 Dopamine receptors making you more sensitive to the dopamine.
However it's not always a good thing.
Volkow warned against something else people use to enhance their activities: caffeine. It disrupts the brain’s balancing mechanism, blocking its process of removing dopamine receptors in response to dopamine spikes, her research shows. Many video gamers down energy drinks, making gameplay even more enticing. “You have to be cautious to avoid compulsive gaming,” Volkow says.