It was long theorized that people make decisions based on integrated global calculations that occur within the frontal cortex (额叶皮层) of the brain, which is considered the seat of higher-order thinking. However, Yale researchers have found that three distinct brain circuits from the frontal cortex connecting to different brain regions are involved in making good decisions, bad ones, and determining which of those past choices to store in memory.
The study of decision-making in rats may help scientists find the roots of bad decision-making common to mental health disorders such as addiction, the authors say. They used a new tool to manipulate (操纵) brain circuits in rats while they were making choices between actions that led to them receiving rewards or no rewards. If the rats made the right decision, one that ended in a reward, one of the brain circuits was activated, but another was activated if the rats made the wrong choice and received no reward. The third circuit stored past experiences and decisions to help the rats with future choices.
Stephanie Groman, lead author of the research says, "A comparison would be deciding on a restaurant for dinner. For instance, without the ‘good choice' circuit you may not return to the restaurant with good food and without the ‘bad choice' circuit you might not avoid the restaurant with bad food. The third ‘memory' circuit is crucial in making decisions such as whether to return to the restaurant after receiving one bad meal after several good ones."
Changes in these circuits may help explain a typical feature of addiction why people continue to make harmful choices even after repeated negative experiences, The Yale researchers previously showed that some of the same brain calculations were disrupted (扰乱) in animals that had taken methamphetamine. "Because we used a test that is similar to those used in studies of human decision making, our findings have direct relevance to humans and could aid in the search for novel treatments for substance abuse in humans," Groman said.
