This theory assumes that the REM is not to throw away memories but to place them. In 'boxes' New memories will be brought into connection with older neural pathways. For example, if someone in a dream turned into another person, is that according to this memory consolidation hypothesis theory, because there is a connection between these two people. That link does not have to do with appearance, but can also be an emotional connection. There are many other theories about the usefulness of dreams. For example, you would learn things in your dreams. The problem is that nobody knows which theory is correct, and on any theory is something to be desired. Yet the dream evaluated, and he must have a function. If a prolonged REM sleep is suppressed, someone is depressed. Yet scientists can not yet say what the function is. Science is busy discovering them.
-Tyler