It‘s a tough life being a laboratory rat – being made to run maze after maze, for hours on end, with only a few chocolate sprinkles as pay. In fact, it‘s such a demanding job that the rats actually dream about it, researchers found out. „We know that they are in fact dreaming and their dreams are connected to actual experiences,“ Matthew Wilson of the Center for Learning and Memory at the Massachusetts Institute of Technology, who led the study, said in a statement. They said their findings were not only fascinating but could shed light on what dreams do for humans. Wilson and graduate student Kenway Louie taught the rats to run around a circular track in exchange for treats. They implanted tiny electrodes in the rats‘ brains – an procedure that scientists say is painless and allows them to monitor the activity of individual neurons. They monitored the rats‘ brain activity while they ran the maze, and then monitored what the brains did when the animals slept. Like all mammals, including humans, rats go through phases of rapid eye movement (REM) sleep, which in humans correlates with dreaming. The patterns were so similar that the researchers could tell where on the maze the rats were in their dreams and how fast they were dreaming they were running.

„Remarkable and amazing“

„It‘s remarkable and amazing to us. I can tell you the first time I saw this it was the most amazing thing I had ever seen,“ Wilson said. He believes the rat dreams have a purpose. Research has shown that humans and other animals learn – even tasks – better when they literally sleep on it. The rat work suggests dreams may be a literal rehearsal. It also shows that the brains of rats are more complex than had been believed. The dream sequences lasted for minutes at a time. And that brings up the question of how „dumb animals“ are treated. Next, Wilson and Louie plan to see if the neural activity correlates with the movements the rats make in their sleep. „Their legs twitch, their whiskers move. They are expressing certain suppressed motor patterns that might relate to what they are actually dreaming about,“ Wilson said. Wilson‘s work reinforces a study last year in which a team at the University of Chicago found that songbirds dream about their singing. Reuters