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The Memory Code

Researchers are closing in on the rules that the brain uses to lay down memories. Discovery of this memory code could lead to the design of smarter computers and robots and even to new ways to peer into the human mind


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Anyone who has ever been in an earthquake has vivid memories of it: the ground shakes, trembles, buckles and heaves; the air fills with sounds of rumbling, cracking and shattering glass; cabinets fly open; books, dishes and knickknacks tumble from shelves. We remember such episodes—with striking clarity and for years afterward—because that is what our brains evolved to do: extract information from salient events and use that knowledge to guide our responses to similar situations in the future. This ability to learn from past experience allows all animals to adapt to a world that is complex and ever changing.

For decades, neuroscientists have attempted to unravel how the brain makes memories. Now, by combining a set of novel experiments with powerful mathematical analyses and an ability to record simultaneously the activity of more than 200 neurons in awake mice, my colleagues and I have discovered what we believe is the basic mechanism the brain uses to draw vital information from experiences and turn that information into memories. Our results add to a growing body of work indicating that a linear flow of signals from one neuron to another is not enough to explain how the brain represents perceptions and memories. Rather the coordinated activity of large populations of neurons is needed.

JOE Z. TSIEN has been an assistant professor in the department of molecular biology at Princeton University since 1997. He came to the U.S. in 1986 after graduating from East China Normal University in Shanghai and working for two years as an instructor at East China University of Science and Technology in Shanghai. He received his Ph.D. in biochemistry and molecular biology in 1990 from the University of Minnesota. He has consulted for several biotechnology companies seeking to develop therapies for age-related memory disorders. The Doogie mouse was a hit in his seven-year-old son's class during show-and-tell.

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Scientific American Magazine Vol 297 Issue 1This article was originally published with the title “The Memory Code” in Scientific American Magazine Vol. 297 No. 1 (), p. 0