The document discusses how the game Flappy Bird triggers the release of dopamine in the brain through achieving goals and scoring points in the game. Dopamine is associated with feelings of pleasure, achievement, and habit formation, which explains why games can be addicting. By its design, Flappy Bird aims to have the player continuously score more points and feel compelled to play again by tapping the icon, triggering more dopamine release and feelings of pleasure and accomplishment in the brain.