Scientists at Beth Israel Deaconess Medical Center (BIDMC),found that dreams may be the sleeping brain's way of telling us that it is hard at work on the process of memory consolidation, integrating our recent experiences to help us with performance-related tasks in the short run and, in the long run, translating this material into information that will have widespread application to our lives. The study is reported in the April 22 On-line issue of Current Biology. This study tells us that dreams are the brain's way of processing, integrating and really understanding new information. Dreams are a clear indication that the sleeping brain is working on memories at multiple levels, including ways that will directly improve performance.
The authors hypothesized that dreaming about a learning experience during nonrapid eye movement (NREM) sleep would lead to improved performance on a hippocampus-dependent spatial memory task. To prove this, the investigators had 99 subjects spend an hour training on a "virtual maze task," a computer exercise in which they were asked to navigate through and learn the layout of a complex 3D maze with the goal of reaching an endpoint as quickly as possible. Following this initial training, participants were assigned to either take a 90-minute nap or to engage in quiet activities but remain awake. Five hours after the initial exercise, the subjects were retested on the maze task.
The non-nappers showed no signs of improvement on the second test -- even if they had reported thinking about the maze during their rest period. Similarly, the subjects who napped, but who did not report experiencing any maze-related dreams or thoughts during their sleep period, showed little, if any, improvement. But, the nappers who described dreaming about the task showed dramatic improvement, 10 times more than that shown by those nappers who reported having no maze-related dreams.
This is interesting because it not only helps to unlock the mystery as to why we dream but it can also lead to a better way of learning and retaining information in the brain. So now when I study for the final exam in this class, I will take nap breaks in between my study sessions so I can dream and remember the class material better.