For the past half-century medical practitioners have come to agree that the brain's memory system is similar to how a computer downloads data from the internet. New theories proposed by German and American scientists, however, are challenging the notion.

The old belief that memories for a day were temporarily stored in the hippocampus, similar to how data passes through the RAM. The hippocampus is a curved part of the brain which fires electric signals during sleep. When this happens, the information goes to the neocortex (which is similar to a hard drive) for permanent storage.

This was the basis of the explanation why people with damaged hippocampi had trouble with creating short term memories but could easily recall old ones because the neocortex is intact.

The old theory made a lot of sense, but new findings by researchers at Brown University and the Max Planck institute of Medical Research suggest a different explanation. They say that the hippocampus is not the engine driving the neocortex. Brown neuroscientist Mayank Mehta says "what seems to be [happening] is that all the neuron types in the hippocampus are showing some echo or antiecho of the neocortex. None of them seem to be driving neocortex."

In a nutshell, there is really no one-way data transfer that happens during sleep. The truth is, they claim, that both parts actually show activity through resonances of information. When all is said and done, the hippocampus is cleared of its content, and gets set for another day of data gathering.

Some experts, however, are not fully convinced that this explanation is entirely accurate. Pointing out to how the research was conducted. "One has to be very careful, in interpreting the results done under anesthesia," he warns, "because it's totally not the same brain." says Bruce McNaughton, University of Arizona director for the Division of Neural Systems, Memory and Aging.

In an act of class and professionalism, Mehta acknowledged the fragility of the theory, saying that many a researcher have been fooled by the brain before, and it will be foolhardy to say that this is how the brain really works at this point.