Editing Sleep cycle (section)

== Alteration ==

The sleep cycle has proven resistant to systematic alteration by [[drug]]s. Although some drugs shorten REM periods, they do not abolish the underlying rhythm. Deliberate REM deprivation shortens the cycle temporarily, as the brain moves into REM sleep more readily (the "[[REM rebound]]") in an apparent correction for the deprivation.<ref name=Hartmann1968 /> There are various methods to control the alterations of sleep cycles:
* Switching off all artificial lights:<ref>{{cite journal |last1=Blume |first1=Christine |last2=Garbazza |first2=Corrado |last3=Spitschan |first3=Manuel |title=Effects of light on human circadian rhythms, sleep and mood |journal=Somnologie |pages=147–156 |doi=10.1007/s11818-019-00215-x |date=2019|volume=23 |issue=3 |pmid=31534436 |pmc=6751071}}</ref> Since the natural production of melatonin can be suppressed by bright light, exposure to light–even after sunset<ref>{{cite journal |last1=L |first1=Tähkämö |last2=T |first2=Partonen |last3=Ak |first3=Pesonen |title=Systematic Review of Light Exposure Impact on Human Circadian Rhythm |journal=Chronobiology International |language=en |date=2019|volume=36 |issue=2 |pages=151–170 |doi=10.1080/07420528.2018.1527773 |pmid=30311830 |s2cid=52960410 |doi-access=free|hdl=10138/311143 |hdl-access=free }}</ref>–may prevent the body from feeling sleepy (and hence entering the sleep phase).
* Meditation and relaxation techniques<ref>{{cite journal |last1=P |first1=Spagnoli |last2=C |first2=Balducci |last3=M |first3=Fabbri |last4=D |first4=Molinaro |last5=G |first5=Barbato |title=Workaholism, Intensive Smartphone Use, and the Sleep-Wake Cycle: A Multiple Mediation Analysis |journal=International Journal of Environmental Research and Public Health |language=en |date=20 September 2019|volume=16 |issue=19 |page=3517 |doi=10.3390/ijerph16193517 |pmid=31547191 |pmc=6801767|doi-access=free }}</ref> 
* Staying away from caffeine before bedtime:<ref>{{cite journal |last1=Anderson |first1=Jason R. |last2=Hagerdorn |first2=Payton L. |last3=Gunstad |first3=John |last4=Spitznagel |first4=Mary Beth |title=Using Coffee to Compensate for Poor Sleep: Impact on Vigilance and Implications for Workplace Performance |url=https://pubmed.ncbi.nlm.nih.gov/29866304/?from_term=coffee+sleep&from_pos=3 |journal=Applied Ergonomics |language=en |date=2018|volume=70 |pages=142–147 |doi=10.1016/j.apergo.2018.02.026 |pmid=29866304 }}</ref> This ensures that the body is not under the stimulant effects of caffeine while trying to sleep.