Science Now + Beyond

This is the number one question about dreams that scientists have been unable to answer

A third of our lives is spent sleeping.

This is a seemingly simple fact but one that always shocks me when I have a night of insomnia and I painfully wish for the sun to come out quicker. Almost everyone dreams for at least two of those hours spent sleeping, whether they can remember it or not.

During that time, the average person has between three and six different dreams per night, which are thought to last between five and 20 minutes. Most dreams, particularly the more vivid ones occur during the REM phase of sleep. However, around 90% of these dreams are forgotten by the time a person gets out of bed.

Nonetheless, while scientists have studied and determined the many benefits of sleep for our health (regulates our metabolism, brain function, blood pressure, etc.), there is still no one answer to the question – why do we dream?

In the early civilizations, it was believed that dreams were a way of contacting with the divine world. Roman and Greek civilizations used to emphasize the prophetic powers of dreams. However, the most well-known theory of dreams of the Western World is the Freudian one. In An Interpretation of Dreams, Freud argues that dreams are the mechanisms by which the self can express its suppressed desires.

Nowadays, the Freudian ideas have been discarded, although there are scientists that still believe that there is a close connection between memory, emotions, the processing of information, and the purpose of dreaming.

At the end of the day, most people dream of things that they can recognize.

The memory consolidation theory is one that defends the connection between dreams and memory. It states that it is in the night when the brain processes everything that has happened during the day.

Cristina Marzano and her colleagues from the University of Rome’s Department of Psychology have proven in a scientific study that the neurophysiological mechanisms that we employ while dreaming, and recalling dreams, are the same as when we construct and retrieve memories while we are awake. This would explain why most of the things that we dream of are based on people and events of our lives.

This is related to the mood regulatory function theory which states that dreams serve to problem-solve emotional issues. Neuroscientist Rosalind Cartwright, also known as The Queen of Dreams, has stated that dreams are the mechanisms used by the brain to incorporate memories, solve problems, and deal with emotions. Therefore, dreams are essential for our emotional health.

Of course, there is also a scientific current of thought that argues that dreams have no function at all. This is called the activation-synthesis hypothesis and it argues that dreams are caused by the firing of electrical impulses of the brain during the REM phase of sleep. However, the fact that animals, particularly mammals, also dream, points out to the idea that they must have some evolutionary or survival purpose.

A study from the University of Turku argues that dreams are a way for us to prepare ourselves for possible future threats. This is the threat simulation theory. This study focused on children that had suffered trauma and looked at how their dreams recreated that trauma to prepare them for something similar occurring in the future. Dreams are, therefore, an evolutionary ability, according to this study, aimed at ensuring survival.

One aspect that all of these theories have in common is that we dream more or remember them much more vividly during times of stress and anxiety. Therefore, dreams might be a sort of coping mechanism to help us process information and emotions.

We know that we dream every night. We know where they come from. We know that there must be a reason for them, yet we still haven’t been able to prove any one reason. For all we know, there might not be one reason, it might, in fact, differ from person to person. Until then, let’s keep dreaming.

By Beatriz Valero de Urquía

Beatriz Valero de Urquia is the Senior Pop Culture and Books Editor at The Tempest. She graduated from the University of Cambridge in 2020 and has written for publications such as Teen Vogue, El Huffington Post, Digital Bulletin and Tech for Good. Beatriz spends her time between Spain and the UK reading, writing and listening to Taylor Swift.