The Sugar Tube Contraption in the Computer

A monkey learns how to use a computer game that rewards him with sugar. When he doesn't get the reward, his brain is flooded with anger chemicals. He never gets anyr anywhere near the same reward any more, but he gets angrier and angrier every time that he doesn't. This hideous cycle just happens where he totally addicted to the thing. It no longer gives him a reward. It only brings him anger to various degrees.