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Why do we dream?

What is a dream?

Dreams include thoughts, images, and emotions that are experienced during sleep. They can range in between extremely emotional to very fleeting, vague, or confusing. Some dreams are pleasant, while others are sad or frightening. Sometimes dreams tend to have a clear story, while many others tend to make no sense at all (Cherry, 2020). There are many unknowns about dreaming and sleeping. What scientists know is that almost everyone dreams every time they sleep, for about two hours a night in total, whether or not they remember it when they wake up (NINDS, 2019). The most vivid dreams occur during rapid eye movement (REM) sleep, and these are the dreams we are most likely to remember. We also dream during non-rapid eye movement (non-REM), but it is known that these dreams are less frequently remembered (De Gennaro et al., 2011). In general, the dream content is collected from the subjective memories of the dreamer upon awakening. Increasingly, objective measures are also used for observation. For example, researchers in one study created a rudimentary dream content map that was able to trace people’s dreams in real-time using a magnetic resonance imaging (MRI) pattern, which was confirmed by the dreamers’ reports after waking up (Horikawa, Tamaki, Miyawaki, & Kamitani, 2013).

But apart from what is contained in a particular dream, the question arises as to why we dream at all.

Why do we dream?

The question of why we dream has fascinated various experts for thousands of years. Despite scientific studies on the function of dreams, there is still no clear response to why we have dreams. Although much about dreaming remains uncertain, many experts have developed theories to explain the purpose of dreaming and new empirical studies are also providing greater clarity. Some of the better-known dream theories state that the function of dreaming is to express our deepest desires, process emotions, consolidate memories, and gain practice in dealing with potential dangers (Cherry, 2020). Many claim that we dream from a combination of these and other factors rather than sticking to one singular theory. Moreover, while many researchers believe that dreams are essential for emotional, mental, and physical well-being, some scientists believe that dreams serve no useful purpose at all (Ruby, 2011).

  • Cherry, K. (2020). Why do we dream?. verywellmind. Retrieved July 22, 2020, from
  • De Gennaro, L., Cipolli, C., Cherubini, A., Assogna, F., Cacciari, C., Marzano, C., . . . Spalletta, G. (2011). Amygdala and hippocampus volumetry and diffusivity in relation to dreaming. Human Brain Mapping, 32(9), 1458-1470. doi:10.1002/hbm.21120
  • Horikawa, T., Tamaki, M., Miyawaki, Y., & Kamitani, Y. (2013). Neural Decoding of Visual Imagery During Sleep. Science, 340(6132), 639-642. doi:10.1126/science.1234330
  • National Institute of Neurological Disorders and Stroke. (2019). Brain Basics: Understanding Sleep. Retrieved July 22, 2020, from
  • Ruby, P. (2011). Experimental Research on Dreaming: State of the Art and Neuropsychoanalytic Perspectives. Frontiers in Psychology, 2(286). doi:10.3389/fpsyg.2011.00286


Author: Alexander Ariu