Dr. Mark D'Esposito

And so then the question is, what does dopamine do?

Well, dopamine is one of the neuromodulators that are made in the brainstem, and it projects up to different parts of the brain.

There's a system that goes up into what we call the basal ganglia, which is important for motor function.

And there's another dopaminergic system that goes up to the frontal lobes.

And what was discovered was that if you deplete dopamine, working memory drops.

You get a significant impairment in working memory if you deplete dopamine.

And if you replace it, then your working memory will be improved.

And so dopamine seems to be a modulator to help this persistent activity stay persistent during the time that you need to keep this information in mind.

Yeah, I think that's a good way of thinking about it.

And one might wonder, well, how can dopamine be important for memory but also be important for movement?

And it's really simple.

It's just that it's acting on different circuits.

The neurons that go to the motor areas that carry dopamine, when dopamine is expressed there and boosted there, then it will be involved in movement.

And lack of dopamine in the basal ganglia will lead to neurological disorders like Parkinson's disease that has severe movement.

difficulty.

But when it's acting in the frontal cortex and expressing the frontal cortex, then it's going to improve working memory.

So it's just the nature of where the circuits are, where the dopamine is, that's allowing it to have different kinds of actions.

And that's for all transmitters.

The reason why acetylcholine seems to be more important for long-term memory is because it

it's projecting to the hippocampus, which we know is another area that's important for memory.