Study Links Dreaming to Increased Memory Performance

A recent study published last week by a Harvard Medical School research team links napping and dreaming to enhanced memory.

Subjects who sleep after memorizing a 3D computerized maze are better at navigating the maze several hours later than those who did not nap, according to Erin J. Wamsley, a research fellow in psychiatry at the Medical School.

While earlier studies have supported the idea that sleep aids in memory consolidation, Wamsley said that the team was particularly interested in studies where rodents showed identical patterns of neural activity both when navigating through a maze and when sleeping afterward. The researchers, led by Medical School psychiatry professor Robert A. Stickgold, sought to investigate this phenomenon in humans.

"If these memories are replaying during sleep, is that going to be consciously experienced?" Wamsley said.

The control group remained awake throughout the experiment and showed difficulty navigating through the maze after the break. The experimental group napped between memorizing and navigating the maze and showed improved performance, according to the study.

More importantly, said Wamsley, experimental participants who spontaneously reported dreaming about the maze showed markedly better performance.

According to Wamsley, the subjects who dreamed about the maze generally performed below average on the first task and performed on par with the rest of the participants for the second task. But after controlling for the poor baseline performance of the dreaming group, their improvement was significantly higher than the other participating groups.

Wamsley said she thought that the initial poor performance of the dreaming group "could be causing them to both dream about it and improve a lot later."

She added that it is possible that the group dreamed about the task because their brains classified the information as important, not necessarily because they deemed the task difficult.

Students said the results of the study helped to confirm something they intuitively knew to be true.

"I find that taking a break from work and taking a brief nap refreshes me and helps me focus better," Rishabh K. Sinha ’12 said. "I think there are diminishing returns to forcing yourself to focus for extended periods of time."

Sinha wasted no time applying the study’s findings to his daily routine. After the interview, he said, "I’m going to go take a nap now."