Every teenager has stayed up late, woken up early, regretted their decision, end then slept extra long the next night.
Can a person really catch up on sleep?
Numerous studies have been conducted on the subject, and what is the prevailing hypothesis is that there are two systems dealing with sleep, a circadian process and a sleep homeostatic process.
The circadian process is a rhythm of sleepiness and alertness over a twenty four hour period. This clock is related to the amount of light received by the eyes and can change when stimulus to the eyes is removed. This cycle is controlled by the suprachiasmatic nucleus in the hypothalamus in the brain. This region of the brain is affected by light and stimulus to the eyes, and it is what causes the circadian process. the interaction of this part of the brain results in changes in hormone levels in the body, promoting either sleepiness or alertness.
The sleep homeostatic process is basically a pressure that builds up during the day that promotes sleep. the pressure dissipates during sleep. Being awake for days can build this process up and cause a difference in brain wave patterns when sleep finally comes. However, brain patterns return to normal after only a night or two of sleep, meaning that a lack of sleep happening as a shock isn't known to have lasting effects yet.
Chronic sleep restriction and sleeping disorders are much different. Getting less sleep than is necessary on a regular basis can cause negative effects to take much longer to wear off and some effects may not be completely reversible. The problem with studying the effects of chronic sleep restriction is that it is difficult to find willing participants for studies and difficult to produce reliable studies because of lifestyle changes caused by sleep restriction.
The physics of all this lies in the fact that all of these effects are caused by electrical and chemical reactions in the brain and body. Also, this was caused by physics. Something as simple as the amount of light entering the eyes can affect the sleep cycles of millions of people.
It is important to get a full night's sleep every night, but one night every blue moon won't make a difference in your life. Chronic sleep restriction is the thing that can cause serious problems to the brain, body, and lifestyle. I'm going to bed.