New research from Carnegie Mellon University researchers suggest that replaying events in the brain may have less to do with creating long term memories than with an active decision making process.
In the study conducted in 2008 and published this month in the journal Neuron, rats had electrodes recording the brain activity of rats as they navigated a maze. In previous studies, rats were measured moving in a linear fashion. Working at The University of Minnesota, they monitored certain neurons, called place cells, which fire in response to physical locations. They enabled the researchers to identify where an event was being replayed based on which place cells were firing. So for example, a rat might be in one place but the firing of the cells showed that it was replaying the events that occurred in another place. They found that rats would replay the path they had experienced less often and that replay is not just important in subsequent moments but important in mapping an entire environment.
The study was funded by The National Institutes of Health, The National Science Foundation and The Pennsylvania Department of Health.