Most of us sleep only once a day but it’s also normal if someone has a nap in the afternoon. For small children napping is a must, whereas babies sleep many times a day, waking up after about every three hours to eat.
What we just described are three different sleep patterns – monophasic, biphasic, and polyphasic. These patterns depend on age, health, sleep quality, and personal preferences. Here we talk about sleep patterns and take a closer look at each of the three sleep patterns.
Sleep patterns and our sleep
We all have a pattern that is a part of our sleep habit. A ‘neat’ sleep pattern means that every day we get enough sleep of proper length, good quality, and at the right time. Each of these conditions is important.
A ‘messy’ sleep pattern means we don’t get the same amount of sleep every night, and our sleep-wake schedule is always different – which results in the accumulation and then repaying of sleep debt, and as a consequence, our sleep is of poor quality.
Our body works rhythmically and many processes rely on our biological clock and circadian rhythm. Thus, a strong routine in sleep habits leads to the good setup and proper maintenance of our circadian rhythm. A lack of routine leaves no space for the proper ‘timing’ of our hormonal release or daily activities and energy levels, so we end up feeling fatigued and unable to fall asleep or stay awake at the proper time.
Processes behind the sleep patterns
In our brains, we have a circadian clock which relies on two things – our habits and external factors, such as the sunlight (or lack of it) that give our brains a cue about the time of the day. It tells us when it’s time to wake up, be active, eat, rest, etc.
The second process lies behind how much we’ve been awake. If we’ve been awake for 20 or more hours, we’re going to be extremely sleepy even though it might only be 6pm. It regulates our sleep homeostasis (sleep-wake balance). This need, this drive for sleep, diminishes with deep sleep (slow-wave sleep). To reach deep sleep, you need to be asleep for at least one hour, because your brain goes through light sleep stages first.
Our ‘clock’ and our ‘timer’ work together throughout the day and a routine helps them stay functional.
Sleep patterns of modern humans
In the past, people used to stop their activities outside with the sunset, go home and prepare for sleep. In dark, melatonin levels increase and people are more tired.
The technology of the new age, together with LED lights and white screens has not only prolonged our daily activity time but also significantly changed our circadian rhythm. As our hypothalamus receives the white or blue artificial light, it understands it’s still daytime, postpones melatonin production, and as a result, our own circadian rhythm isn’t in tune with nature so our sleep onset is postponed.
What are sleep pattern types?
If the circadian rhythm works so that we sleep at night and are active during the day, isn’t that conflicting to the idea of biphasic and polyphasic sleep? It might be in the circadian sense, but you could actually get your body and mind used to different sleep patterns.
Just keep in mind that those patterns might have advantages as well as some disadvantages, and – if you decide to adopt a new sleep pattern, you have to strictly stick to it, in order not to end up with a complete mess of your sleep.
Here are the most frequent sleep patterns.
This means you sleep only once per day and is considered ‘normal’ sleep by most adults. The length of sleep depends on age and personal needs, with teenagers needing about 10, adults about 8, and elderly who sleep for about 7 hours daily.
Biphasic sleep usually consists of one long period of sleep and one nap during the day. In some countries, biphasic sleep is a part of the culture. The famous siesta is a nap after a good lunch. This type of biphasic sleep is not a surprise – humans naturally have an energy drop in the afternoon, usually after lunch time. This sleepiness is a part of our circadian rhythm.
In biphasic sleep, the nap is not as short as power naps of about 20 minutes. It’s usually longer – about one hour and a half. This way, the long nap allows the brain to go through all sleep stages – light sleep stages 1 and 2, deep sleep (stage 3) and REM sleep (and maybe even repeat light sleep). A person who wakes up from REM or light sleep will feel refreshed and not dragged by sleep inertia.
Interrupted sleep is a type of biphasic sleep where there is a short period (1-2 hours) of nighttime wakefulness dividing two long periods of sleep. The awakening usually happens after the REM stage. Some studies have shown that this sleep pattern occurs naturally in humans if they are exposed to a 14-hour darkness period. There’s also plenty of historical evidence that people used to sleep twice every night before the industrial revolution. It is hypothesized that artificial light has completely changed our sleep habits so as our day is so long, we have ‘no time’ for interrupted sleep, but have to squeeze our sleep in only one chunk of 8 hours.
Polyphasic sleep consists of many short episodes of sleep, usually between four and six. Although a normal pattern of babies, it is not common with children and adults. You can make a polyphasic sleep schedule if you find it useful, though. Three most common types of polyphasic sleep are called Everyman, Uberman, and Dymaxion.
Each of them takes a long amount of time to get used to, usually with periods of poor sleep and sleep deprivation until a person is fully adjusted. They can be useful only if you have a very strong reason to completely change your sleep patterns, as they require your time, motivation, dedication, and a strict schedule.
Everyman sleep pattern consists of four sleep episodes, where one is significantly longer than the rest. The long period of sleep lasts for about three hours (between 1am and 4am), and the remaining are three 20-minute nap periods which can be arranged like this – 9am, 2am, 9am.
Uberman is a 6-nap pattern where every sleep period is about 20-30 minutes and occurs every three hours. This is possible to maintain only if your work-sleep schedule is your priority because if you miss one nap, you might suffer severe consequences until the next. Uberman can be practiced if you want to cut back on sleep – you’d have three hours of sleep altogether.
Dymaxion allows only two hours of sleep – with 30-minute naps after six hours of wakefulness. This sleep pattern is extremely difficult to maintain and may only work for those who don’t need much sleep naturally.
Polyphasic sleep – for and against
However, these short naps can’t provide you with the needed amount of REM and deep sleep – which means you’re running the risk of being sleep deprived without realizing it. Another problem for these unusual sleep patterns is the rhythm of society. With an 8-hour working shift plus an hour, two (or more) commuting, it might be very difficult to maintain polyphasic sleep.
If you’re a student who needs to be more productive and has no better solution, you can try and adopt one of these patterns – some argue that they have more energy during the day when on this schedule. However, remember that when we deprive ourselves of some sleep stages, our brain might resort to something called REM rebound and deep sleep rebound.
These rebounds occur when we’re deprived of one sleep stage. In order to make up for it, our brain tends to ‘jump’ straight to that stage as soon as we fall asleep. This means that our body cuts back on light sleep – which as important as other stages. They all have a specific, important role either in learning and memory, body and tissue repair, immune system and hormone release.
Overall, it is good to know about polyphasic sleep as it can come in handy during the times of crisis when sleep deprivation is inevitable and it’s impossible to get the needed amount of sleep. To mitigate the effects of sleep deprivation, you can take short naps frequently.
Fragmented sleep is generally polyphasic sleep, but not ‘in order’, and is a result of one of the disorders like irregular sleep-wake syndrome, circadian rhythm sleep disorder, obstructive sleep apnea, or insomnia. It happens in all disorders that cause frequent night awakenings and prevent a person from going through all sleep stages without interruption.
Excessive daytime sleepiness is a usual symptom of these disorders.
Fragmented sleep can also be caused by strong stress, emotional trauma, or benign reasons like drinking too many liquids before bed.
- Hegarty S. The myth of the eight-hour sleep. BBC News. February 22, 2012. https://www.bbc.com/news/magazine-16964783 Accessed February 4, 2019.
- Sleep We Have Lost: Pre-industrial Slumber in the British Isles. The American Historical Review. April 1, 2001. http://ahr.oxfordjournals.org/content/106/2/343.full.pdf+html Accessed February 4, 2019.
- Sleep patterns for babies. Pregnancy, birth & baby. February 2017.
https://www.pregnancybirthbaby.org.au/sleep-patterns-for-babies Accessed February 4, 2019.
The information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. Read our full medical disclaimer.