Dreams and REM Sleep
What happens if you don't get any REM sleep? Originally, researchers thought that no REM sleep meant no dreams. Now, scientists have confirmed that dreaming is not confined to REM sleep, and that people dream during NREM sleep.
Researchers have also determined that people can function with no major adverse effects when they are deprived of REM sleep, but we cannot survive without NREM sleep. People who have injuries to the brainstem, which controls REM, do not face adverse psychological effects due to REM dreaming deprivation.
Yet, in the study of dreams, people are often awakened during REM sleep so that they can give dream reports. Dream reports taken at this time are typically longer, more vivid, more emotional and more structured than those taken after NREM sleep. And lucid dreams, or dreams in which people are aware that they are dreaming, usually occur during REM sleep.
In people who have REM sleep behavior disorder (RSBD), the body does not experience temporary paralysis, or muscle atonia, as is typical during REM sleep. Instead, they act out their vivid dreams through sudden movements and vocalizations. RSBD is a parasomnia, or a disorder involving unusual experiences that disrupt sleep. Many researchers would argue that dreaming cannot be divorced from REM altogether.
Still, some researchers say that there isn't much connection between the two, though most believe that dreaming is likely influenced by REM. Even though REM sleep is no longer synonymous with dreaming, there is still debate over the exact relationship between dreaming and REM.