Some mornings, you wake up and the dream is right there. Clear and vivid. You might still feel the emotion in your chest, and it can take a few minutes to remember where you are and what was real.

Other mornings, you open your eyes and there is nothing. Just a quiet sense of having slept.

You might know people who think they do not dream. However, the reality is we all do. Sometimes we have many in one night.

What varies is whether people remember their dreams and how often they remember them.

Dream recall myth vs reality

During the night, we cycle through periods of light sleep, deep sleep and rapid-eye-movement (REM) sleep. A full cycle takes about 90 minutes.

People generally spend more time in deep sleep in the first half of the night and more time in REM sleep in the second half.

The main function of deep sleep is restorative: to replenish energy, repair our bodies and help store memories.

REM sleep is important for memory consolidation and emotional processing. Later in the night, REM sleep becomes longer. This is the stage most closely linked to vivid, emotional dreaming.

If you wake up during or just after REM sleep, you are much more likely to remember a dream. If you wake from deep sleep, you probably will not, even though you were dreaming........

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