What then might be the nature of a structure or micro-region in our brain that holds the memories from past dreams? If these memories are not held in the hippocampus (like most other memories) and if these dream-based memories are often only available when other dreams are being produced, then there might somehow be a separate structure of micro-region for their storage. Perhaps, in some way, this separate memory unit is related to the important function served by REM sleep in the consolidation of memories from daytime experiences.
Memory Consolidation
Recently, attention has been directed to the role played by REM-sleep (and dreams) in the nighttime selection, consolidation, and storage of daytime memories. Much of this attention evolved from the widely acknowledged dysfunction of sleep-deprived people in their capacity to remember events of the previous day. Many of us are acutely aware of this phenomenon, having stayed up all night to prepare for a college exam, only to discover (painfully) that we “forgot” almost everything when asked to recall specific facts during the next day’s exam.
We now know that our failure to retain important information doesn’t just relate to fatigue or excessively compact retention of important information. It relates to a process of memory consolidation that should have occurred during the previous night of sleep. This consolidation includes sorting through short-term memories. Which do we want to keep, and which do we toss out? Then, a consolidation takes place that involves integrating multiple experiences and extracting generalities. These creative, integrative processes seem to be taking place in our dreams or in processes that parallel our dreaming.
I recall the retention process being used by someone called a “mnemonist” by the noted Russian neuropsychologist, Alexander Luria. In his book about the mnemonist, Luria (1987) reported that this man, who could remember everything, would imagine a city street and place what he had been asked to retain in store windows along this street. Later, the mnemonist would revisit this city street and recall what he had placed in the windows. I wonder if something like this is occurring in our dreams. Are we using the visual (and perhaps auditory) displays in our dreams to somehow store our consolidated memories? We might even be creative in bringing several consolidated memories together in one store window (or whatever visual or auditory display we invent).
Perhaps we place the new memory in a store window that we have previously constructed, creating the schema suggested by Frederick Bartlett (1995) in his classic studies of memory. His schemata might be engaged when dreams are built on top of previous dreams (progressive or recurrent). My Starved Rock nightmares might be made up of memories regarding not just my fearful experience of the Fox River cliff but also stories I heard or read about Indians starving on the rock. These memories are gathered together in a store window or schemata that powerfully and poignantly consolidate Fear (falling off the rock) and Injustice (starving Native Americans and courtroom proceedings). This schema seems to be operating throughout my life, and it has motivated many of my social reform thoughts and actions in adulthood. It might have been forged or at least reinforced through my Starved Rock dreams.
With all of this occurring, might some of our store windows be reserved for content from old dreams, especially if they can be placed in one of the existing windows (schemas)? We might even bring in Carl Jung’s (1959) concept of universal archetypes, suggesting that some of the windows might be frequently constructed and used by all of us. I am being highly speculative at this point; however, I would like to gain some appreciation for the complex –and perhaps elusive – way in which we retain memory of past dreams when producing new ones.
