News Brief by Kathryn Gibb
Researchers have discovered the details of neural activity patterns in rats’ brains that help inform decision making. Prior research showed that past experiences can affect decision making in rats, but the brain circuit level processes behind this had not yet been explained. This new research, led by scientist Shantanu Jadhav, focused on tracking the brain behavior of rats moving throughout a maze. Jadhav’s team concentrated their research on the hippocampus and prefrontal cortex regions of the brain. The researchers found that neurons in the prefrontal cortex of the rats were either activated or inhibited while mentally replaying their maze experience.
Those neurons associated with the replay of the experience were activated whereas those less engaged during movement throughout the maze were inhibited. This neural activity was tracked by looking at short bursts of electrical activity (sharp-wave ripples) associated with replaying the maze experience. By suppressing the less engaged neurons, the rats’ brains were able to optimize awake memory function, therefore helping with informed decision making. Similar research by a team at the University of California San Francisco discovered that neural activity in the hippocampus helped the rats form memories specific to location. Alongside Jadhav’s research, this location-specific memory formation may help scientists understand how past experiences can affect behavior and decision making.
NIH/National Institute of Mental Health. "Circuit for experience-informed decision-making identified in rats: Memory and executive hubs work in lockstep during awake mental replay." ScienceDaily. ScienceDaily, 11 March 2016. <www.sciencedaily.com/releases/2016/03/160311125019.htm>.