Feb 06 2010
More Neurotransmitter News: Social Status and Dopamine
Yesterday serotonin, today dopamine. New research suggests a relationship between dopamine and social status.
Okay, let’s clarify. First, dopamine is a neurotransmitter that could be described as a natural “reward” chemical in the brain. When dopamine levels are increased in the brain, subjects might describe their state with words like “aroused,” “eager,” “excited,” “interested.” Drugs such as caffeine and cocaine will increase dopamine levels.
Maybe reward isn’t the best word. Low-levels of dopamine has been implicated in addictive behavior. By gambling, for example, it is believed that subjects get shots of dopamine increase. Anticipated reward might be a better term. Increasing dopamine levels can help with the lethargic, apathetic component of depression. The depressed person may feel “it doesn’t matter,” and thus lack motivation. “Get out of bed, why? Leave the house, why?” Anticipating a positive outcome is strong motivator.
In the news of the research found over at Eurekalert, I learned that it was not the actual levels of circulating dopamine that was discovered to be related to social status, but the dopamine receptor density in the brains of the subjects. Interesting. In yesterday’s post about serotonin, I mentioned that neurotransmitter levels alone don’t tell the whole story. There can be many conditions, including much circulating neurotransmitter, but few receptors, as well as little circulating neurotransmitter and many receptors. Etc.
What about the social status part? Unfortunately, the article didn’t mention how that was measured. My guess: some sort of questionnaire. The neurotransmitter receptor density part was measured with PET scans.
The result -
[I]ncreased social status and increased social support correlated with the density of dopamine D2/D3 receptors in the striatum, a region of the brain that plays a central role in reward and motivation, where dopamine plays a critical role in both of these behavioral processes.
The lead author, a Dr. Martinez, offered an explanation for the results -
“We showed that low levels of dopamine receptors were associated with low social status and that high levels of dopamine receptors were associated with higher social status. The same type of association was seen with the volunteer’s reports of social support they experience from their friends, family, or significant other.”
That certainly is food for thought. Of course, the important word to highlight is correlated/associated. The study result was a found relationship. Is it a causal relationship, with the number of dopamine receptors causing greater social involvement and striving and eventual success? We don’t know. Nonetheless, an intriguing bit of research. And I absolutely loved the concluding paragraph:
These findings are particularly exciting because they put human neurobiology into a social context, and we humans are fundamentally social creatures. It is in these social contexts that the biological effects on behavior obtain their real meaning.
Our thoughts, feelings and behaviors are not guided by the whispering of angels; their genesis is not in a metaphysically meaningful quantum fluctuation. No, that’s not what science tells us. For those who are listening, we are learning that the mechanisms that generate our psychological selves — as intricate and complicated as they are — reside in the natural world. A very rich world that the increasingly powerful tools and methods of science is revealing to us, bit by fascinating bit.
