Sleep mystery remains unsolved
'I have a dream," so said Martin Luther King. The imagery evoked by this word is hopeful and gentle, showcasing all that is noble, idealistic and beautiful from the depths of our being.
But dreams are not always so, as Hamlet reflected: "To sleep perchance to dream, A'ye there's the rub." And there is the rub -- dreams may be happy and frivolous but they may also be monstrous and terrifying.
Dreams are collections of images that occur during sleep and over which we have little voluntary control. They occur about 90 minutes into sleep in what is known as the rapid eye movement (REM) phase.
The areas of the brain concerned with memory, the hippocampus and the amygdala, which processes emotions, are active.
Several periods of REM are interspersed throughout our sleep even though we rarely recall few if any of the dreams.
Interestingly, researchers have found that the same themes recur in dreams across all cultures and age groups and these include slipping, falling, unpreparedness for exams, slow-motion actions, abandonment and being chased.
Another feature is that dreams always have a surreal quality to them. This is because the pre-frontal cortex of the brain, which helps us make sense of the world, is inactive during sleep. It results in memories of various events from different times of our lives being presented in a simultaneous mishmash.
External factors can also make dreams more bizarre and include medications such as antihistamines, hormones and antidepressants and also fever and foods such as cheese or spices eaten near bedtime.
Do dreams serve any purpose though? This is hotly debated. Freud considered them "the royal road to the unconscious" believing they brought to consciousness material that was hidden even from the individual themselves.
Some believe dreams help us integrate new and emotionally changed information with previous memories, so we can make sense of the new information. For example, if you are upset about a recent event you may dream about previous distressing periods in your life.
Studies of brain processes during REM sleep find the part of the brain that stores previous visual memories is overactive during dreaming and links current themes with the past.
Similarly, some say dreams may also help us rehearse for the future. So a person in love might dream of weddings, allowing them to mentally prepare. Many of these perspectives are not yet confirmed.
But as well as fluffy, happy dreams, they may also be terrifying and overwhelming. These are nightmares. Unsurprisingly, they occur during periods of great distress in life.
Psychiatric conditions such as depression and PTSD are specifically associated with nightmares. Children, who have a greater tendency to experience nightmares than adults, dream of monsters as an expression of fears they don't understand. As understanding and an ability to deal with difficulties emerges with maturity, nightmares decrease.
Psychoanalysts specifically examine the symbolism of dreams and nightmares and they believe while surreal images may have biological explanation, these are more than just a haphazard concoction of uncensored memories. Instead they interpret the content and direct its meaning to the person experiencing it.
Treatment implications flow from these diametrically opposing views. Dream interpretation is recommended for alleviating nightmares by some. More recent work has focussed on shorter interventions.
Imagery Rehearsal Therapy (IRT) is an example that involves around 12 hours of therapy during which the subject is assisted in changing the content of the dream and rehearsing this in imagery so that the distress is diffused or refocused on some other image.
This technique has been tested in controlled trials with positive outcomes. Unfortunately, I am unaware of any therapist practising IRT in Ireland.
Meanwhile the uncertainty as to whether dreams are symbolic representations of suppressed emotions or are simply haphazard memories is still unresolved.
Originally published in
