New experiences enhance learning by resetting key brain circuit

Wednesday, February 24, 2021

A study of spatial learning in mice shows that exposure to new experiences dampens established representations in the brain’s hippocampus and prefrontal cortex, allowing the mice to learn new navigation strategies. The study, published in Nature, was supported by the National Institutes of Health.

“The ability to flexibly learn in new situations makes it possible to adapt to an ever-changing world,” noted Joshua A. Gordon, M.D., Ph.D., a senior author on the study and director of the National Institute of Mental Health, part of NIH. “Understanding the neural basis of this flexible learning in animals gives us insight into how this type of learning may become disrupted in humans.”

Dr. Gordon co-supervised the research project with Joseph A. Gogos, M.D., Ph.D., and Alexander Z. Harris, M.D., Ph.D., both of Columbia University, New York City.

Whenever we encounter new information, that information must be consolidated into a stable, lasting memory for us to recall it later. A key mechanism in this memory consolidation process is long-term potentiation, which is a persistent strengthening of neural connections based on recent patterns of activity. Although this strengthening of neural connections may be persistent, it can’t be permanent, or we wouldn’t be able to update memory representations to accommodate new information. In other words, our ability to remember new experiences and learn from them depends on information encoding that is both enduring and flexible.