Sleep experts explain why your dreams are so vivid that you remember them long after waking up

• The most vivid dreams typically occur during rapid eye-movement (REM) sleep.
• Research indicates the brain is just as active during REM sleep as it is when you're awake.
• If you have recurring nightmares that are disturbing your sleep, consider Imagery Rehearsal Therapy.

Dreams have had a powerful grip on the human mind for millennia. As soon as humans could start writing, they were documenting dreams. 

But for all of the tens to hundreds of thousands of hours we spend snoozing over a lifetime, we only remember certain dreams long after waking up. These are called vivid dreams.