Ever wonder why we forget our dreams?

We do most of our dreaming in the third phase of our sleep cycle, which is known as the Rapid Eye Movement (REM) stage when we experience deep sleep. New research published in the journal Science has now revealed that this stage also contains a period of active forgetting.

This happens, the study suggests, to protect our brain from overloading on the information. In fact, the neurons that go on erasing our dreams are the same ones that help control our appetite.

For this study, the scientist tested a group of mice and monitored their brain activity as they slept.

One of the last region to sleep in the brain is the hippocampus, a curved structure that sits inside each brain hemisphere and is critical for moving information from short-term memory into long-term memory. The hippocampus may also be the last to wake up.

In many cases, the dream is deposited in our short term memory rather than moved to your long term memory bank, as the hippocampus isn’t fully awake when you are.

This is why you lose vivid details of your dream.

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