How could we forget dreams? They are such a mundane but essential part of life, and yet scientists still understand almost nothing about them. This includes the question: Why do we even dream?
If one takes a step back and thinks about it, dreams are quite strange. Every night when your body falls unconscious, your brain conjures up an imaginary reality that exists only in your head but that you think is real. When you wake up, almost all of it disappears from your memory. Despite how strange it sounds, dreams are taken for granted as a fact of life, much like brushing your teeth or going to work.
Although the actual need for dreams remains unclear, the related activities that occur during REM sleep are understood and plentiful: long-term memory strengthening, flushing the brain of toxins, increased “secretarial” work, and so on. This makes it even stranger that we know so little about dreams themselves.
These questions are not anything new. Speculation on the cause and meaning of dreams has been a fixture of human fascination for tens of thousands of years, going at least as far back as the ancient Greeks and Egyptians. Despite the modern technology at our disposal—from MRI scanners to EEG detectors—theories about the origins and purpose of these mysterious experiences will, at least for now, remain theories.