Advanced Psychopharmacology

Dopamine and Reward Video Transcript

Speaker 1: You've probably heard of the dopamine link to reward, or the dopamine reward circuit, or the dopamine reward hypothesis. I want to have a closer look at this phenomenon, because it's actually quite interesting. The dopamine reward circuit is found deep in the brain. Dopamine originates in a brain stem structure called the ventral tegmental area, and it is transported to the nucleus accumbens, which is activated by dopamine during the experience of pleasurable stimulation. So from this, we get the reward hypothesis, based on the observation that pleasurable experiences are invariably associated with elevated dopamine in the brain, things like food, sex, video games, cocaine, or Oreo cookies. Therefore, 2: Dopamine is the cause of pleasurable sensations in the brain.

Of course, it's never quite this simple. Dopamine increases without the source of pleasure don't lead to pleasure on its own. Instead, they lead to increased desire for the stimulus, and increased seeking behaviors, which are sometimes referred to as cravings. Mice with no dopamine in their brains don't seek food, and will starve to death even in the presence of food, but if you put it in their mouths, they do chew, swallow, and give pleasure indicators in their bodies and facial expressions.

Also, dopamine levels are elevated when behaviors are unexpectedly rewarding. Drug dealers count on this, and that's why they use the marketing strategy that the first time is free. So casinos and drug dealers are expert dopamine manipulators, so expert that I imagine you will recognize what city this sign is for before I've even completed it. So I want you to think about the fact that you are motivated to seek rewards, and the next time you're just dying for your favorite treat, thank dopamine.