There is new research about rapid-eye-movement sleep or REM by Dr. J. Allan Hobson a psychiatrist and sleep researcher from Harvard. His paper published in the Nature Reviews Neuroscience stated a difference of opinion about the main function of REM when dreaming occurs. He states that REM is physiological due to the brain is anticipating sights, sounds and emotions when waking. He also feels that REM continues during waking hours but is only suppressed which might explain daydreaming. Further studies might conclude that those that can't suppress REM might indicate the basis for Attention Deficit Disorder or ADD.
These findings about REM sleep are found in studies that detected dreaming in humans, warm blooded mammals and birds. REM has also been found in third trimester humans well before the child has experienced dreaming. A fetus may be visualizing something long before their eyes open, while sounds and emotions in their dreams will come later.
According to researchers who studied more than 1,000 subjects at Carnegie Mellon University and Harvard found that people can remember their dreams and even some have the ability to watch and control them without waking up. Remembering your dreams or lucid dreams occur right before waking which supports Dr. Hobson's findings. Participants could remember a dream more often than not if a nightmare was associated with something they hated verses something or someone they loved. Remembering a positive dream worked in the same way.
Further studies are needed to determine if people have lucid dreams while sleepwalking or having night terrors. Sleepwalking and night terrors result in muscle activity and non-REM sleep. Narcolepsy a sleep disorder where you fall asleep during the day and is related to abnormal REM sleep, including hallucinations, sleep paralysis and cataplexy (loss of muscle control).
Sleep, a journal by Ursula Voss of J. W. Goethe at the University in Frankfort conducted experiments analyzing brain waves during REM sleep, waking and lucid dreaming. The results showed that lucid dreams had elements of REM and of waking. In conclusion, lucid dreams also play a part in falling asleep as participants experienced dream recall if only for a second when they closed their eyes. Dream recall has been known to act as a sleep aid to help individuals fall asleep faster.
If you are having trouble falling asleep, try to recreate your last lucid dream. Keeping a journal next to your bed and maintaining a record of your dreams and sleeping habits have been beneficial for some people to fall asleep easier.