Dopamine is known as one of our “happy” chemicals that makes us feel good. Neurologists and other specialists formerly believed that in order to activate movement, a sudden amount of dopamine was released. However, recent studies have disproved that theory.
In a study done by Harvard Medical School, mice were researched which had a specific genetic disorder, making them lack dopamine chemicals. For them, a malfunction in the RIM gene means a slower production of dopamine. A similar disease for humans is Parkinson’s disease, which is also a result of a lack of dopamine. Although the mice’s dopamine production was slowed, they were still able to function properly and perform numerous motor skills. Despite this, they struggled when put in scenarios which involved actions that would require motivation and some type of reward for them. For example, they were not motivated to drink water, unlike mice without a dopamine deficiency.
To take it up a notch, they provided the dopamine-lacking mice with a medication often used for Parkinson’s patients, called L-Dopa. It is unknown whether this medication truly restores dopamine in the brain, or just fills in for it in order to help with motor issues. It was found that when the mice were under this medication, their motor skills became more advanced, but within their brains nothing regarding signaling was seemingly improved. Through this study, it was discovered that the L-Dopa medicine is able to assist with motor skills, but not cognitive movements, since it is unable to truly replace the rapid dopamine release that the brain needs.
Since the mice were still able to perform motor movements, it is clear that they had some level of dopamine being released. However, it was not the copious amounts they needed in order to perform higher-level processes. Ultimately, it was shown that dopamine is released over time for some lower-maintenance skills, but released in one surge for more skilled tasks.
This discovery is important because it gives us a better understanding of ourselves and how our minds work. When we are low on dopamine levels, that does not mean our body will necessarily shut down, but now we know that our cognitive and reward motive skills will weaken first. Our motor skills will go second because they require less dopamine chemicals to act out. In addition, this is important for Parkinson’s disease patients because it has helped scientists discover what the L-Dopa medicine actually does, and helps lead us in the direction of what needs to be done to create a medicine that will enhance cognitive skills within patients.
