On occasion I’ve mentioned REM sleep. Some people have asked, “What is REM sleep?”
It stands for Rapid Eye Movement sleep and is the last stage of sleep where the EEG wave pattern is similar to the waking brain with some of the characteristics of both the alpha and beta states that are earlier states of sleeping. As a point of interest, the alpha state is also that same state that one finds themselves in when meditating, or when in “the zone,” or when daydreaming. Is this the state that a meditating Buddhist enters the mandala during a Tantric meditation (see below)?
REM is that time during sleep when we dream and when our eyes move rapidly under their lids as though tracking what they see, though that part of the theory has not been shown to be true. However, having said that there are those theories that continue to suggest an eye-brain correlation during REM sleep in that because of the discontinuous nature of most dreams, the brain is “looking” around the dream-scene trying to make sense of these discontinuities. We have these same discontinuities when awake, only the brain smoothes them all out and projects what looks like a linear presentation.
It has also been theorized that this jumping around of the mind’s eye during REM sleep may actually cause the sense of discontinuity and that the dream images actually come at us in an entirety which the mind then has to linearize (sort out) to make sense of it all. We may be doing this in the waking world as well which is why the concept of time (a construct of the mind that does not actually exist in the physical world) was created as a means of sorting it all out. It’s interesting how Tibetan Thangka paintings show the entire life of an individual in a circle surrounding the Buddha suggesting that the person’s life is all happening at once.
“Time is nature’s way to keep everything from happening at once.”
But let me get back to REM. During REM a normal person’s musculoskeletal system (which is your body movement system) is suppressed or shut down. Why? Well we don’t have solid answers for this, but we do have research that points to reasons for this. Some evidence suggests that one of the reasons for dreaming includes both memory consolidation and memory erasure. In the erasure mode, any memory that is not reinforced becomes weakened. Memories with physical reactions are strengthened through repeated physicality, thus those memories brought up during sleep would be less likely to be retained if there were no physical reinforcement. This ‘feedback loop’ is shut down during REM.
There’s also the added advantage that when we were all huddled together against the cold in our dark and lonely caves, the dreaming of the day’s physicality would not be reenacted to the annoyance of your neighbor you’d be punching and strangling thinking that you were being attacked by some Saber-tooth tiger. Of course this theory only holds up for ‘unwanted’ memories with some other activity being responsible for the retention of those memories needed for survival. But don’t dismiss the erasure concept too quickly because if our brains could not erase the unwanted (which is enormous when compared to the wanted) we would need bigger brains to hold it all. This is in fact what we see in animals who have huge brain mass compared to their body mass and who have no REM. As a matter of fact studies have shown that when someone is deprived of REM sleep for too long, the brain goes almost instantly into REM and resists any further attempt to prevent it. So REM seems to be an adaptation for those creatures with higher order neural network systems such as ours.
It also gives us many hours of entertainment projecting meaning onto the sleep visions that may or may not have any inherent meaning. But isn’t this pretty much like the rest of our lives where we are continuously projecting meaning onto every object, person or event? Seems to me that dream interpretation of meaning projection is a pretty non-confrontational way of looking at what’s going on inside of you and around you. And who knows, higher-level self-awareness may just be the next neural adaptation the evolving human is developing.