It doesn't really work that way.
There are five easy ways to know that you are sleep deprived, even if you don't think you are.
- Eyelid twitching. Your eyes want to close! Your lids are tired and need a break. You might also discover your vision has blurred, or you might be compelled to rub your eyes because they are dry or itchy, also signs you have kept them open much longer than they are meant to be open.
Remedy: Go to sleep. Seriously. Do it now.
- Fidgeting. You might call this a "second wind," but what it really means is that your body is using stores of adrenalin to function because you are sleep deprived and need to sleep so your body can recover from lack of sleep. You might feel antsy or hyperactive or on edge.
Remedy: Find a way to relax (warm bath, massage, soothing music), then... Go to sleep.
- Unexpected appetites. You might be hungry at odd hours, or you might feel like you can't satiate your hunger, or you have some odd cravings that aren't normal for you. Your body has more than one biological clock; besides the main one that controls your overall processes, which aligns with the circadian rhythms of the Earth, your body also has clocks that time your hunger drive and digestive processes so that you eat at wakeful times and sleep during slow digestive periods. This is why you normally don't need to empty your bowels overnight; your body's separate digestive clock is in charge of slowing the process so you can have a period of sleep uninterrupted by the need to use the bathroom.
What does this have to do with sleep? If you are sleep deprived, your circadian rhythms are confused and your biochemistry suffers as a result, as hormones and neurotransmitters rely on balanced circadian rhythms to do their work. A sleep-starved brain turns to survival mechanisms if this imbalance continues, signaling your body to feel hungry to inspire it to consume calories to compensate for the exhaustion that sleep deprivation brings.
Remedy: Go to sleep. After a good night's rest (or several in a row, if you are seriously sleep-deprived), your body and brain will re-coordinate your eating plan.
- Illness. If you allow yourself to go for too long, too frequently, without quality sleep, your body's immune system can become compromised. Sleep brings healing at the cellular level to fix the day's insults and injuries; it also cleans out the pathways of the brain and sends growth hormone out to recharge the body. Without sleep, you don't get these benefits and general malaise, dizzy spells, nausea and, more seriously, viral and bacterial infections and immune system challenges can be the result.
Remedy: Go to sleep.
- Microsleeping. Ever just nod off briefly, then catch yourself and reawaken? That is considered a "lengthy" microsleep. Many instantaneous moments when your brain dips into sleep mode occur without the sleep deprived even being aware of them. Your brain is equipped with both sleep and wake drives (much like hunger and thirst drives) and if you don't allow your body to surrender naturally to the sleep drive (because you are on a long road trip or working a late shift or trying to finish your thesis, for instance), you may intellectually think you are awake when, actually, your sleep drive is stealing microseconds of sleep.
This is a very big deal. A microsleep on the job can result in a performance error or an accident. A microsleep behind the wheel is predictably what leads to drowsy driving accidents. If you are sleep deprived, you will not be a match for an under-indulged sleep drive. The brain's need to shut down is a powerful force and it will eventually shut you down, even if you are still placing finishing touches on that master's thesis.
Remedy: Go to sleep.