A dream can be explained as a succession of sensations, emotions, ideas, and images that occur involuntarily in a person’s mind during certain stages of sleep. It’s not really understood what the purpose and content of dreams are, but they have certainly been the subject of religious and philosophical interest and a topic of scientific speculation throughout recorded history. Interestingly, the scientific study of dreams is known as Oneirology.
It’s during the REM (rapid eye movement) stage of sleep that dreams mainly occur, because this is when brain activity is high and most resembles that of being awake. It’s the continuous movements of the eyes during sleep that identifies REM sleep; however, dreams can occur during other sleep stages, but these dreams tend to be less memorable and much less vivid. (1)
Our dreams vary in length: they may last for just a few seconds, and they’ve been known to last for between 20 and 30 minutes. The reason why some dreamers are able to recall their dreams is because they have been woken up whilst in the REM phase of sleep.(2) On average, people have between three and five dreams each night, with some having up to seven; however most of our dreams are quickly forgotten. It seems that our dreams tend to last longer as the night progresses and, when we have a full eight-hour sleep, the majority of our dreams occur in the typical two hours of REM.
Today, many people see dreams as a connection to the unconscious mind. There are varying natures of dreams, such as exciting, frightening, melancholic, magical, adventurous, and even sexual; (3) and our dreams seem to range from normal and ordinary right through to bizarre and completely surreal. With the exception of lucid dreaming, the events that occur in our dreams are normally outside the control of the dreamer. The dreamer is self-aware during lucid dreaming. Sometimes, dreams can implant a creative thought, thus giving the dreamer a sense of inspiration. (4)
Throughout cultures and time, opinions have varied and shifted about the meaning of dreams. It seems that people generally endorse the Freudian theory of dreams, and that is that dreams reveal hidden emotions and desires. Other theories are that dreams help us in problem solving, in memory formation, or that they occur simply due to random brain activation.
Some people have a sleep disorder in which they physically act out their dreams during sleep called REM Behavior Disorder (RBD). In this case, acting out dreams can be dangerous to the individual and bed partner.
Going back around 5000 years ago in Mesopotamia, the earliest recorded dreams were documented on clay tablets. In the Roman and Greek periods, people believed that dreams were messages sent directly from one or more deities, from deceased people, and that they were the predictors of the future. Then there were cultures that practiced dream incubation, their intention being to cultivate dreams of prophecy.
In the early 1900s, Sigmund Freud wrote extensively about the theory of dreams and their interpretations. Freud believed that dreams are a manifestation of our deepest anxieties and desires, often relating to repressed childhood obsessions or memories. In addition, it was his belief that almost every dream topic, irrespective of its content, represented the release of sexual tension. In Freud’s Interpretation of Dreams 1899, he developed a psychological technique whereby dreams could be interpreted; he also devised a series of guidelines to help us understand the motives and symbols that appear in our dreams.
© 2020 American Sleep Association.