What's the difference between dopamine and serotonin?

Inspiration

• I often confuse these two neurotransmitters, but I want to understand them better to prevent the mix up.

Findings

• Dopamine is primarily about anticipation and pursuit, and serotonin is more about contentment and stability
• Dopamine fires hardest not when you get the reward, but when you expect it. It’s the drive toward the thing, not the satisfaction of having it, which is why the slot machine pull feels more compelling than the win, and why the scroll never resolves. The subjective feel tends to be activating, forward-leaning and a little restless
• Serotonin is less about reward-seeking and more about a baseline sense of “I’m ok, I have enough, I’m safe.” It’s associated with mood stability, social belonging, and the felt sense of completeness, not oriented toward anything in particular. The stillness after a genuinely good meal, being in the sun with nowhere to be
• A useful tell is that dopamine highs almost immediately generate wanting more while serotonin highs feel complete. You can ask yourself in a given “good” moment, am I leaning toward the next thing, or does this feel like enough?
• They also interact. A dopamine chase can land in a serotonin state if the reward was real (finishing something meaningful, genuine connection), but dopamine loops can be self-sustaining: seeking without ever arriving

Dopamine

• Its precursor chemical is L-DOPA, which is synthesized in the brain and kidneys
• The brain includes several distinct dopamine pathways, one of which plays a major role in the motivational component of reward-motivation behavior.
• The anticipation of most types of rewards increases the level of dopamine in the brain
• Many addictive drugs increase dopamine release or block its reuptake into neurons following release
• Pop culture portrays dopamine as the pleasure chemical, but pharmacological opinion is that dopamine controls motivational salience
• Dopamine is one of the ways our brains control our movements

Serotonin

• It’s involved in sleep, thermoregulation, learning, memory, pain, sexual activity, feeding, motor activity, neural development and biological rhythms

Differences

• Dopamine is released in conjunction with your body’s movement towards acquiring something (food, sex, water, drug). Dopamine is also involved in attention, perception, motor function, and memory formation. This drives you outwards, it increases the feeling of wanting something and helps your body prepare itself for doing what is required to achieve that.
• Serotonin is released in response to (simply speaking) a state of satiation. The feeling you get after sexual climax, eating a good meal, etc., is a release of serotonin. This helps you relax and feel content.
• While serotonin reuptake inhibitors (antidepressants that stop your brain from clearing out serotonin) are used in managing mood disorders, there is no conclusive evidence that there are any abnormal levels of serotonin in people with depression.

Etymology

• Dopamine is a contraction of 3,4-dihydroxyphenethylamine
• The first name of serotonin was enteramine. The most likely explanation is that it was first synthesized and made available for research by the American drug company, Upjohn Pharmaceutical, who chose the name “serotonin.”