Dopamine plays several crucial roles in our brain and body. Here are a few key points:
Dopamine is a major neuromodulator in the brain, acting as a chemical signaling messenger. Its best-known function is in the brain's reward circuitry, which is a system that tells us something is reinforcing in our environment. This could be a stimulus that makes us feel good or better, although that's a gross oversimplification. This reward circuitry evolved as a mechanism to increase our survival, signaling to us which stimuli in our environment are important for our survival or dangerous.
Dopamine can also have powerful effects on the inflammation system. It interacts with the brain stem and some of the neurons that innervate the spleen and other areas of the body that deploy cells to combat infection, inflammation, and pain. Dopamine can modulate pain and even transform our experience of pain into something that's pleasurable.
The way dopamine is released in the brain and body can differ. It can be very local, or it can be more broad. Dopamine can change the way that our neural circuits work at a local scale and at a very broad scale. However, increasing dopamine levels indiscriminately can make motivation short-lived. It's more beneficial to optimize the peak to baseline ratio of dopamine release.
In summary, dopamine is a crucial neuromodulator that plays a significant role in our reward circuitry, pain modulation, and neural communication.