Sleep and Dreams

Sleep is a very strange thing indeed.  And dreams are even stranger.  I have always felt like sleep is a kind of temporary death, because it is a period where you have no self-awareness and are not actively in control of your thoughts and body.  Dreams vary in terms of how realistic they are and what kind of experience they offer, but I almost never feel any real control in my dreams and even my ‘thoughts’ in dreams seem to be outside of my control.

We know a lot more about sleep now, though we still don’t understand exactly why we need sleep.  We know, for example, that there are five stages lasting a total of 90-110 minutes on average.   Stage 1 is light sleep, stage 2 is where we spend 50% of our sleep time and is characterized by much slower brain waves and occasional bursts of brain activity.  Stages 3 and 4 are called ‘deep sleep’ and there is no eye movement or muscle activity.  People awakened out of deep sleep are generally disoriented.

The final stage is the well-known REM sleep.  This is where most of our dreams occur.  Our breathing is rapid and shallow, and our muscles are paralyzed, presumably to prevent us from acting out our dreams.  This accounts for 20% of our sleep time.  As we go through the night, the deep sleep periods decrease and by morning almost all our sleep is spent in stage 1, 2 and REM.

We also know that sleep is linked to our circadian rhythms, which appear to be strongly influenced by light and other ‘zeitgeber’ (German for time-giver) cues.  The body produces melatonin to induce a feeling of sleepiness.

As one might imagine, sleep is a complex phenomenon and falls prey to many disorders.  A significant percentage of adults struggle with some level of insomnia, and sleep deprivation is quite common.  Sleep gets more precious with age, as a great majority of the elderly have difficulty sleeping.

So, sleep has yielded some of its secrets to the probing of electrodes and scientific study.  But what about dreams?  Dreams have content and that content cannot easily be interpreted from brain scans.  We rely on human beings to relate their dreams.  And it turns out that many of us have very similar dreams, and even similar nightmares.

For centuries dreams were interpreted as visions and omens, foretelling the future or providing insight into a problem or decision.  Some people solve problems or come up with ideas in their dreams.  Psychologists have used dreams as a major part of their psychoanalysis efforts – interpreting dreams in terms of repressed desires, childhood traumas and other psychological baggage. 

Freud famously associated much of dreaming with our complex sexual identities.  And certainly there is enough dreaming about sex and romance to make one believe that sexuality plays a significant role.  But more recent researchers have new theories that stem from analysis of what parts of the brain are active during dreams.  

One line of research suggests that dreaming is a type of data dump meant to clear your brain of the day’s activity and prepare it for the next day – a kind of garbage disposal.  The data is either transferred to long term memory or woven into a strange fabric of dreams that can be processed and eliminated as it parades through your sleeping state.

Another theory is that dreams are a simulation of possible future dangers and allow you to prepare for these threats with an unconscious fire drill while you sleep.  This might account for the dreams of anxiety that we often experience – missed exams, inability to flee a dangerous situation, and other disquieting dreams.  

On a brighter note, some dreams are an attempt to fulfill our deepest desires – flying, playing professional sports, riding a horse on a beach, kissing that girl you never kissed, and so on.

One aspect of dreaming that intrigues me is how a specific sensation – melancholy, joy, fear – can manifest itself so powerfully in a dream and stay with me for hours after I awaken, even when I can no longer recall the details of the dream.

But I generally find dreams to be an unsatisfying experience – never quite real enough when they are pleasant, and all too real when they are disturbing.  The absurdity of having the same dream of missing class an entire semester and then facing the final exam over and over again astounds me.  Is my brain so pathetic that it can’t come up with a novel way to entertain itself while I am asleep?

Are dreams entirely a product of various electronic signals in our brains?  Is there a deeper significance to the strange brew of thoughts and activity that we experience while dreaming?  If the dream state is any indication of what existence will be like after the body has died, then I will be sorely disappointed.  I miss the full pleasure of my physical senses in my dreams.  They are not as crisp and clear. 

But of course once the body dies even the brain waves will no longer be present, so it is unlikely that dreaming is a preview of life after death.  If there is truly a ‘soul’ that exists once the body is gone then hopefully its sensations and experiences will be much more ‘realistic’ and enjoyable, and not the capricious mishmash that comprises human dreams.