The memory of your skiing trip yesterday hasn't erased the memory of your picnic on the beach last summer. Your memories accumulate, without being crushed as they go, but why? Researchers at Cornell University (Ithaca, United States) studied the sleep of mice and identified a key to this process.
It has long been known that memories are replayed during sleep. This is an essential step in their consolidation in our long-term memory. Faced with this uninterrupted influx of information, the brain has developed a mechanism that allows it to avoid interference: separating the "replay" sessions. New memories on one hand, old ones on the other. This is the result of a new study, published in the prestigious journal Nature.
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