In particular, Mehta and his team looked at three connected brain regions in mice -- the new brain or the neocortex, the old brain or the hippocampus, and the entorhinal cortex, an intermediate brain that connects the new and the old brains. While previous studies have suggested that the dialogue between the old and the new brain during sleep was critical for memory formation, researchers had not investigated the contribution of the entorhinal cortex to this conversation, which turned out to be a game changer, Mehta said. His team found that the entorhinal cortex showed what is called persistent activity, which is thought to mediate working memory during waking life, for example when people pay close attention to remember things temporarily, such as recalling a phone number or following directions.Sleep specialists who don't understand sleeping. Say it ain't so.
"The big surprise here is that this kind of persistent activity is happening during sleep, pretty much all the time." Mehta said. "These results are entirely novel and surprising. In fact, this working memory-like persistent activity occurred in the entorhinal cortex even under anesthesia."
"This is a whole new way of thinking about memory consolidation theory. We found there is a new player involved in this process and it's having an enormous impact," Mehta said. "And what that third player is doing is being driven by the neocortex, not the hippocampus. This suggests that whatever is happening during sleep is not happening the way we thought it was. There are more players involved so the dialogue is far more complex, and the direction of the communication is the opposite of what was thought."
Ask a narcoleptic. One of you please, just once ask us.
The first half of the night is filing, sorting through the day, consolidating relevant memories and discarding the others. The second half of the night is pinging those new items of information to see if they match or change any old items. Basic database storage and synchronization.
