PITTSBURGHReplaying recent events in the area of the brain called the hippocampus may have less to do with creating long-term memories, as scientists have suspected, than with an active decision-making process, suggests a new study by researchers at Carnegie Mellon University and the University of Minnesota Medical School.
In a study of rats navigating a maze, the researchers found that replays occurring in the hippocampus were not necessarily recent or frequent paths through the maze, as would be expected if the event was being added to memory. Rather, the replays often were paths that the rats had rarely taken or, in some cases, had never taken, as if the rats were trying to build maps to help them make better navigation decisions.
In a report published March 11 in the journal Neuron, Anoopum Gupta, a Ph.D. student at Carnegie Mellon's Robotics Institute and the Center for the Neural Basis of Cognition, and his colleagues say their findings suggest replays in the hippocampus are not merely passive echoes of past events, but part of a complex, active process of decision making.
In addition to Gupta, the researchers include Carnegie Mellon Computer Science Professor David S. Touretzky and A. David Redish, associate professor of neuroscience, and Matthijs van der Meer, a post-doctoral researcher, from the University of Minnesota.
"Our work provides clues into how animals construct a complete, fully navigable representation of their environment, even if they've only partially explored that environment," said Gupta, who also is a medical student at the University of Pittsburgh School of Medicine. "The cognitive maps created in this way may allow animals to plan novel routes or shortcuts. As we learn more about the neural mechanisms that enable animals to flexibly navigate through the world, we hope to apply those lessons to research in robotics that could improve autonomous navigation systems."
The team used electrode "hats" to r
|Contact: Byron Spice|
Carnegie Mellon University