Keeping memories intact requires plenty of sleep
To find out what time of day is best for learning, undergraduate Meagan Shinbashi spent late nights in the lab giving memory tests to mice.
Meagan Shinbashi has always been interested in why we need sleep, so when she saw an undergraduate position in the lab of Craig Heller, a professor of biology who studies the neurobiology of sleep, she jumped at the chance to join the lab.
At the time, Shinbashi was a sophomore biology major with an inkling that she might want to head to medical school. Her project was to test at what points during the sleep/wake cycle mice were best able to form new memories. To do that, she used a standard memory test that involves timing how long mice spend investigating objects in the cage. Items that are familiar from a few hours before merit less investigation than new ones introduced while the mice were out of that cage.
One of the first roadblocks that Shinbashi ran into had to do with gauging a mouse’s learning curve: “What we learned is that if the test is too hard, the mice don’t learn at any time of day.”
Weeks into her project, she found herself having to rethink the entire experimental protocol. “Research was nothing like what I was expecting,” Shinbashi said. “I was expecting clean crisp results every time.”
But that’s not the way research works. “I was very surprised by how slow research is and the amount of time it takes to get clean data,” she said. “When you actually get something, it’s really exciting.”
After refining the number and placement of objects in the test, Shinbashi tried again. This time she found that the nocturnal mice learned best in the middle of their day (our nighttime), if they have a chance to sleep before being asked to remember the objects. They also learned well when awakened in the middle of their sleep cycle (our daytime), which was unexpected.
“That would be our equivalent of getting up at midnight and studying and being able to learn,” she said. “That was a bit surprising.”
After working in the Heller lab during the school year, Shinbashi was accepted into the Stanford Bio-X summer undergraduate research program, which brought her in contact with faculty research from across disciplines. She credits that Bio-X experience for providing crucial knowledge to prepare for her next adventure: a quarter working in the Kyoto lab of Shinya Yamanaka, who won the Nobel Prize in physiology or medicine for discovering how to create stem cells from a person’s skin.
When Shinbashi returns to Stanford, she said, she’s still interested in applying to medical school, but possibly with a research twist: “At least I’ll have a better idea of the research behind the medicine and have a deeper appreciation for that work.”