Sleep debt is the concept that if you skip half an hour of sleep now, you'll need to catch it up later. I would expect though, that if you skip some sleep, but then start having a normal amount sleep, that gradually your sleep debt would decrease (decay) by itself. Has there been any research on how sleep debt decays?
Very little research exists and over a long period of time it may not even be possible..., the model I work under is this:
If you sleep less than your body would like to, then you pay for it, either you pay for it in terms of more sleep the next day, or you pay for it in terms of lost alertness, creativity, or mood.
If we were cattle, and all we had to do was eat and stand, then sleep deprivation wouldn't make that much difference to everyday life - similarly if the thing we have to do in a day is travel, then being sleep deprived might not make a difference when all you are doing is sitting on a plane seat for 15 hours.
But if you work in a creative, intellectual, or life-or-death trade, then being 10% off your best can have serious long term implications (junior doctors working on little sleep are the classic case). I suspect that the trade off isn't this simple but consider it as a question - you can wake up an hour early every day of your life, but you'll be only 95% percent of the person you could be - would you take that choice?
According to the Sleep Docter, you cannot just catch up on sleep. You will eventually return to normal when catching up, but it will take a lot longer than you would generally expect according to a few studies in this aricle.
Personal experience suggests the decay is quite slow.
Ie debt maintains at or near 100% for beyond 7 days.
Again - if personal experience is any measure then I sense it also depends on age of the person also and possibly fitness level.
I could skip a nights sleep without much effect when I was in my 20s but I'm a bit older now and I notice my ability to concentrate is affected substantially by sleep debt until 'caught up'
In 2004 there was a reality show/ TV game series in the UK called 'Shattered' - where the object of the game was to stay awake long as possible.
I did very much wonder how long they slept for - after the game was over.
The winner endured 178 hours of sleep deprivation.
There were doctors and psychiatrists attached to the show - it would be great to hear their 'after' stories.
Incidentally the winner was female and I started wondering if there is a difference between genders regarding need to recover sleep debt.
It does not seem implausible to me that women are able to recover sleep debt faster -if evolution has played a part - when you consider the sleepless nights involved in child rearing.
It would also be interesting know of the effects of modafinil - a drug that allows users to stay alert for around 40 hours without sleep I believe. It is reported that users can continue off the drug without making up the debt.
Likewise the question of the effects of Caffeine on sleep debt is an interesting query.
Seems like I've answered your question with more questions ! Sorry but just trying to lay out the different areas you'd need to look at to fully answer this.
There is however some interesting research reported here
And with apologies for stating the obvious - the Wikipedia Page is also very useful