During the day we pay attention to what goes on around us, process information, make decisions, and experience various emotions. When we sleep, we disengage from our surroundings and we pay attention to an internal world of events, images and people. Dreams are fascinating and mysterious and have kept people wondering for hundreds of years. What do they mean? Do they serve a useful function? Although we have several ideas, we don’t yet have a straightforward answer as to what they do.
Upon the discovery of electroencephalography or EEG for short, the placement of electrodes on the scalp to record electrical activity from neurons in our brain, we became confident that we would be capable of understanding all the mysteries that sleep holds. We have of course learned a lot, and we have been able to understand the changes in electrical activity throughout the night. We know that when we sleep, we go through different stages and spend more time in a phase called slow-wave sleep or deep sleep in the first hours of the night and every 90 minutes or so we go through a phase that is distinct and strange. This final stage of the sleep cycle is the REM sleep or rapid-eye-movement sleep stage, also known as paradoxical sleep. Our eyes are moving fast and our brain is very active as if we are alert, but we are indeed sleeping and our bodies are paralysed.
Intrigued, sleep scientists came up with the idea to wake people up when they were in REM and to ask them if there was something they were thinking at the time. The vast majority reported dreaming, so REM sleep and dreaming became very strongly connected. As time passed, this paradigm was explored more and it started to become obvious that dreaming is not a phenomenon that strictly emerges in REM sleep, but it also happens during NREM sleep, albeit less frequently. Often people don’t remember having a dream, while at other times not only do they remember having one but they are aware of the sensation and they even join in, actively controlling the dream and its outcome, what is known as lucid dreaming. It is also possible to know that you have dreamt but not remember anything about the dream itself, which may be annoying. You may think of Freud and the hidden meaning of dreams however many before him had already proposed several ideas on dreams that still hold today. We know for example that when we dream we often incorporate stimuli from our environment into our dreams, such as a siren or an alarm. We also know that we dream about things relevant to our experiences during the day, known as the ‘continuity hypothesis’, that dreams are in a way a continuation of what goes on during waking. One of my favourites is the formula by Sante de Sanctis (1862-1935), which stated that to understand dreams we need to consider one’s previous experiences, personality etc, what goes on in their life at the present and finally, the conditions during sleep. It is interesting that oftentimes, we may come up with solutions to problems that we could not resolve during the day, known as the ‘a-ha phenomenon’.
Dreams are images or scenes that we experience during sleep, which can be very brief or long and complex. Studies on dreams have revealed that we all dream about similar things. We mostly dream of people that are doing some kind of activity, and usually, the place where these actions take place is secondary, often unknown. There may be abrupt changes in the scene, where at the end of the dream we find the primary actors in a totally different place to the one they started in. Children tend to have more dreams about animals than people. Adults have more dreams about strangers and acquaintances than family members. Our most vivid dreams tend to happen closer to the morning hours and prior to our waking in the morning, which may be why we tend to remember those more. Some of the most common dreams are being chased, falling, trying to do something repeatedly, or losing a tooth!
At times we may have a bad dream or even a nightmare, an intense negative dream that wakes us up and upon waking we still think about it and analyse it in great distress. Unfortunately, we all have nightmares every now and then. The majority of people experience a nightmare at least once each year, and some have one every month. From a clinical perspective, it is considered significant to have a nightmare every week, a good hint, that something needs to be addressed. Nightmares may emerge after a traumatic event, but these tend to be different from mainstream nightmares. Trauma-related nightmares are more of a vivid re-enactment of the traumatic experience rather than a dream, which is again a sign that there is still unresolved trauma that needs to be addressed and sorted for the nightmares to go away.
The jury is still out pondering on what dreaming may do for us and the hypotheses range quite a bit, from being useless random images, to being useful because of problem-solving and emotional processing. No matter what position you adopt, for now it suffices to think of dreams as a continuation of wakefulness. You may have heard of the expression ‘the sleep of the just’ for someone that sleeps serenely. Sleep is a continuation of our waking life. If we carry no burdens, we sleep well. If we have unresolved issues, these will pop up during sleep. If we address the issues that bring distress in our lives when awake, our sleep and dreams will reflect that peace and our dreams will probably be fascinating stories to share with others.
Key Reference: Zadra, A and Stickgold, R. (2021). When Brains Dream. WW Norton & Company, New York.
Posted in sleep on Jul 01, 2023