Most people can easily recall at least two good and two bad dreams they’ve had over the course of their lives, but why they had those dreams, and what the dreams actually mean is a topic of ongoing debate in the scientific community.
Experts generally agree that a dream is a series of subconscious images that occur when you sleep and this state can also include sounds, sights, and other sensations. Dreams happen most frequently during rapid eye movement (REM) sleep, a deep sleep state that means you are less likely to be disturbed.
But as for the purpose of dreams, and why people remember some dreams and not others, that phenomenon is still under research to discover what we do and don’t—know about the thoughts and images, and what we experience during sleep.
Early in the night, dreams only last a couple of minutes but they increase in length as you get more REM sleep. Another theory suggests that dreams are the product of a “data dump” for the brain; it processes important events and happenings of the day (expressed as dreams) and deletes insignificant memories.
Experts and scientists aren’t entirely sure why we dream, but ongoing research is using neural imaging to find relationships between the contents of a dream and activity of brain patterns. One thought is that the hippocampus (which controls memory) works hand in hand with the neocortex, which tends controls higher-level thought, in order to create reasoning out of all the information your brain has collected, which may be experienced or played out as dreams.
Some experts believe that having a dream is related to signals sent to the cortex during sleep. Some of these signs are vital for memory and learning, but some are seemingly random. Your brain might try to interpret these signs by joining them into a cohesive story, resulting in a dream.
Of course, it’s possible that some dreams are just about wish fulfillment. This includes your standard flying dream relating to a desire for freedomdrea or a dream about driving relating to a concern about your life’s direction. But while it is fun to speculate about a dream’s meaning, remember: Sometimes, a dream is just a dream.