Monday, March 15, 2010
Neuroscientists have known for many years that the neurotransmitter dopamine plays a major role in drug addiction.
More recently, scientists have discovered that dopamine also plays a big part in basic risk-taking behavior.
For example, Time wrote in 2007:
Everyone can learn from their mistakes — but some people have genes that may make it harder. That's the message from German researchers, writing in tomorrow's issue of the journal Science, who have shown how a common gene variant affects some people's ability to respond to, and learn from, the negative repercussions of their actions...
Those men, it turns out, had a particular gene variant, or allele, that reduces the density of receptors for dopamine — a neurotransmitter that plays a key role in motivation, pleasure and addiction — in certain areas of the brain...
It's the first strong physiological evidence that the density of dopamine receptors may affect how people respond to negative inputs. Previous studies have established a strong link between a low density of dopamine receptors and addiction, obesity and compulsive gambling — conditions that suggest an impaired ability to learn from the consequences of bad decisions.