Many of us have experienced the following: the day before an exam, we try to squeeze a huge amount of information into our brain. But just as quickly as we acquire it, the knowledge we have gained is gone again. The good news is that we can solve this problem. With expanded time intervals between a person's learning events, we keep the knowledge for a longer time.
But what happens in the brain during the spacing effect? It is generally thought that during learning, neurons (经经元) are activated and form new connections. In this way, the learned knowledge is stored and can be regained by reactivating the same set of neurons. However, we still know very little about how pauses positively influence this process.
Neurobiologists Annet and Pieter did an experiment, during which mice had to remember the position of a hidden chocolate piece in a maze (迷宫). On three continuous chances, they were allowed to explore the maze and find their reward—including pauses of different lengths. "Mice trained with the longer intervals between learning phases (阶段) were unable to remember the position of the chocolate as quickly," explains Annet. "But the next day, the longer the pauses, the better was the mice's memory."
"If three learning phases follow each other very quickly, we naturally expect the same neurons to be activated," Pieter says. "After all, it is the same experiment with the same information. But after a long break, we imagine the brain interprets the following learning phase as a new event and processes it with different neurons."
However, the researchers found the opposite. In fast continuous learning phases, the mice activated mostly different neurons. When taking longer breaks, the same neurons active earlier were used again later. Reactivating the same neurons could allow the brain to strengthen the connections between these cells. With spaced learning, we may reach our goal more slowly, but we benefit from our knowledge for much longer.