Neuroscience Seminar by Dr. Byungkook Lim (Professor at UCSD Biological Sciences)

Dr. Byungkook Lim, Neuroscience Professor at UCSD, presented on motivation and dopamine to the high school members of TYP

On December 11, 2022, UCSD Neuroscience Professor Dr. Byungkook Lim presented on the connections between motivation and dopamine to the members of Total Youth Productions (TYP) in the TYP office. His lecture ultimately taught how dopamine levels can be managed to improve motivation.

Dopamine is an important neurotransmitter, a molecule that transmits information in the brain, that controls a wide breadth of brain functions ranging from motor skills to mood. Suggestive of its diverse roles, dopamine, if imbalanced, can cause diseases as varied as Parkinson’s disease, depression, ADHD, and drug addiction. Dopamine has been long associated with motivation, but Dr. Lim’s research has proved that the two have a direct relationship. The professor used optogenetics, a technique that uses light to control specific neurons in the brain, in mice to demonstrate dopamine’s effect on behavior. The mice were placed into a test chamber with two sections differentiated by the pattern on the floor. The mice had their dopamine-producing neurons stimulated in one side of the chamber but not the other. Both during and still after the experiment, the mice showed a very strong preference for being in the side of the chamber that they had been stimulated in. The results of this experiment show a direct causative relationship between dopamine and motivation. But what is motivation? How is it different from liking something? Dr. Lim defined motivation as the “active and current desire to do something”. “Motivation”, he says, “is always connected to a reward.” And motivation is connected to dopamine, the baseline of which fluctuates over time. The first time a monkey is trained to do a task for a reward, it has a dopamine boost when it receives the unexpected reward. But when the monkey later learns to expect the reward, it gets a dopamine boost when it gets the cue for the reward and dopamine change of the actual reward becomes negligible. And when the monkey expects a reward but doesn’t receive it, there is a sharp drop in dopamine. This tried-and-tested result of classical training shows that dopamine boosts associated with a reward decrease over time. For example, if someone starts regularly drinking boba, the first boba they have will be much more enjoyable than a boba several weeks into the regimen. Therefore variation is key when it comes to using a reward to motivate yourself. Furthermore, the baseline level of dopamine tends to rise when you do a dopamine-increasing activity, such as being on your phone, with high frequency. Since difference in dopamine levels causes motivation and increased mood, more dopamine is required to have the same positive effects (this is how drug addiction happens). Therefore it is important to have a healthy baseline of dopamine. Dr. Lim recommends activities like light exercise, meditation, and journaling for helping to restore dopamine levels to a healthy baseline.