Dopamine is known as the feel-good neurotransmitter—a chemical that ferries information between neurons. The brain releases it when we eat food that we crave or while we have sex, contributing to feelings of pleasure and satisfaction as part of the reward system. This important neurochemical boosts mood, motivation, and attention, and helps regulate movement, learning, and emotional responses.
In lab experiments, dopamine prompts a rat to press a lever for food again and again. This is no different in humans, it’s the reason why we partake in more than one helping of cake. This press-the-lever action applies to addiction as well. People with low levels of dopamine may be more prone to addiction; a person seeking pleasure via drugs or alcohol or food needs higher and higher levels of dopamine. This neurotransmitter enables us not only to see rewards but to take action to move toward them. Stimulants both legal (methyphenidate) and illegal (cocaine), increase levels of dopamine in the brain, and alter behavior accordingly.