Diminishing Returns - Why sleeping less to work more is counterproductive
Finding enough time to sleep is often a difficult task for most students. One study reports that nearly half of university students suffer from poor sleep and of the students asked at the University of Edinburgh, only 38% reported getting more than 8 hours of sleep. Balancing coursework, socialising, work, and any other commitments as a student may often mean that sleep is forgotten about, despite its importance.
Image description: Funmi's work features collection of photographs and poetry centred around the female body. The image is vivid, piecing together images that would normally feel far-removed from one another but that work together in harmony - reminiscent of a dream like state.
The sleep-wake cycles:
Our sleep-wake cycles are regulated by two processes: the circadian rhythm, and the sleep-wake homeostasis. The latter is your body’s way of keeping track of how much sleep you need for proper function. For example, longer and deeper sleep after a period of sleep deprivation is the result of sleep-wake homeostasis. However, the homeostatic process is connected to the circadian rhythm - the 24-hour cycle consists of different responses of the brain to outside stimuli such as light and temperature. Not following these natural cycles can result in sleep-wake homeostasis and your circadian rhythm becoming misaligned.
The SCN (suprachiasmatic nucleus) within the hypothalamus of the brain serves as the internal clock of the body that receives information about light levels from your eyes. At night, or otherwise, under darker conditions, the SCN sends signals to the pineal gland which increases melatonin production, which induces what we feel as ‘sleepiness’ before we fall asleep.
During sleep, we experience a period of reduced activity with changes in certain physiological functions such as brainwave activity, breathing, heart rate, and body temperature change.
The four sleep phases:
Sleep is usually divided into four phases: Stages one to three comprise NREM (non-rapid eye movement) and stage four focuses on REM (rapid eye movement) sleep. All four of these phases occur cyclically during sleep - NREM phases make up 80% of each cycle, and each complete sleep cycle lasts between 90 and 120 minutes.
There is a lot that we still don’t know about the NREM sleep phases, but here is a summary of what we do: in the three NREM stages, brainwaves, breathing, body temperature, and heart rates continue to decrease and muscles relax more with each stage. Stage one NREM usually lasts a few minutes and marks the beginning of a sleep cycle. It is characterised by alpha (8-13 Hz frequencies) and theta (4-7 Hz) brain waves - both of these are similar to awake brainwave patterns. Stage two is the longest sleep phase in all sleep cycles and is characterised by sleep spindles - bursts of higher frequency brain waves which may impact learning and memory consolidation. This stage is also distinguished by K complexes, which are our brain’s responses to external stimuli like sound but work to prevent awakening as a response to these stimuli and progress the sleep cycle into stage three NREM. Also called the deep sleep phase, stage three is marked by delta waves (less than 3 Hz) and is restorative - cell repair is initiated by the release of the human growth hormone (HGH) by the pineal gland. Stage three shortens with each complete sleep cycle.
The REM sleep phase that follows the NREM phases is an even bigger mystery - the brain behaves completely differently during REM sleep, and we don’t know why. During REM we experience rapid eye movement and an increase in breathing, heart rate, and brain wave activity. The REM phase lengthens with each new sleep cycle. Most dreaming occurs during the REM phase and the muscles of the body go through paralysis in this stage - it is thought that this prevents us from acting out our dreams. However, some dreams, such as night terrors, occur in the NREM cycles. The process and causes of dreaming remain very poorly explained, but they may aid us in regulating and processing our emotions as well as healthy brain function.
Why are you sleep-deprived?
Sleep is demonstrably important in all aspects of our lives, but getting enough sleep can be difficult. Factors such as stress, light levels, consumption of alcohol, certain diseases (such as long COVID), and certain medications (like antidepressants) can all affect the amount and quality of our sleep. While many of these can be out of our control, there are certain things we can do to improve our sleep amount and quality. For example, limiting light and noise where you sleep as much as possible will allow your brain to work through the sleep stages without outside stimuli. Limiting light doesn’t just include turning your lights off and shutting the blinds, it also includes TV and phones - between 11 and 14% of Scottish adults agree that watching TV or using social media before falling asleep negatively affects their sleep. Avoiding caffeine and exercise late in the day can also help limit the disturbances to our circadian rhythms by not disturbing the levels of cortisone and endorphins.
Stress is another big factor that affects our sleep - 27% of adults in Scotland reported that the Coronavirus pandemic and associated stress have decreased their sleep quality. Studies have shown that meditating or otherwise relaxing before going to sleep may decrease stress and result in better quality sleep.
Taking long naps or napping in the late afternoon may also decrease the quality of sleep: napping for longer than 10-20 minutes may allow your brain to enter deeper sleep (from which waking up is reported to be more harmful...which might be a hint to stay asleep). Taking a nap that is too long may or napping too late in the day, however, may disrupt your sleep cycles, furthering sleep deprivation.
What happens when you are sleep deprived?
Sleep-wake cycle disruptions:
The disruption of our sleep-wake cycles can result in decreased cognitive function as well as physical changes. A change in the circadian rhythm can lead to weight gain, impulsiveness, insomnia, and memory problems. Some of the results of this change may further the disturbance in the rhythm, creating a positive feedback loop.
NREM sleep deprivation:
During NREM sleep phases, specifically, stage three, physical recovery and regeneration take place. Synapses enter a recovery period during NREM sleep, allowing the brain to ‘pick up’ new things and learn - the brain enters a restorative period during which it strengthens the connections between synapses. The ability of the brain to change and recover this way is called neuroplasticity, and it is essential for learning. One study even showed that a lack of deep sleep can result in increased sensitivity to pain. A lack of NREM sleep has also been linked to diabetes, heart disease, immunodeficiency, high blood pressure, and the worsening of chronic pain.
REM sleep deprivation:
The REM phase is vital for cognitive development, memorisation, and retaining knowledge. The information that we pick up and learn during the day is consolidated during deep sleep stages, so getting enough sleep is essential to maintaining and strengthening our memories. The same process that our brain undergoes during NREM sleep is responsible for memory consolidation during REM sleep. A lack of REM sleep is also often associated with an inability to concentrate, an increase in stress levels, and a decline in mental health - specifically an increase in anxiety. In Scotland, 49% of adults report that a lack of sleep harms their mental health.
It has also been shown that serious sleep deprivation (staying awake just 24 hours) has similar effects on alertness and responsiveness as a 0.1% blood alcohol content (twice the legal amount in Scotland).
How can you get better sleep?
Being a university student is a delicate balancing act, but making enough time for quality sleep is vital for better mental and physical health and improved academic performance.
The simplest way to ensure better sleep is to create the ideal sleep environment - cool, dark, and quiet. Closing any blinds, limiting outside noise and exposure to screens are all things you can do to create your ideal sleep room.
Taking time off-screen not only lowers screen and light exposure but also decreases stress. Allowing yourself time to destress before sleep may be very difficult, but so important - stress disturbs sleep, which can cause further stress. Meditating, reading a book, journaling, or taking a bath are some of the many activities that are recommended to do before sleep to decrease stress.
Being careful about when you exercise is another factor that is in your control - limiting late-night workouts is a simple way of getting better sleep. Working out is certainly healthy and can contribute to good sleep - if not done too late in the day.
Watching your caffeine intake during the day and adjusting it to your own sleep schedule is a very common and effective way to improve sleep, especially if you are a big coffee drinker (like many of us are). Be careful of nicotine and alcohol as well though, as their effects also take hours to wear off. Instead, taking a melatonin supplement a few hours before going to sleep has become a very popular sleep aid (we're not recommending trying anything though, other than going to bed a bit earlier!).
In general, keeping a constant daily routine is the most sure-fire way to keep your circadian rhythm intact. Waking up and going to bed at similar times every day is the only way to ensure this though, which can be difficult for a student. However, making time for a quick nap early in the afternoon is the simplest short-term solution to improving your sleep cycles - some even suggest drinking a cup of coffee before taking a nap. Sounds counterintuitive? Yes - but the logic behind the advice is that caffeine takes between 20 and 45 minutes to start working, so you should wake up and feel refreshed after the nap.
I hope you find the time for good sleep (or nap) today - trust me, it will improve your life. Especially with the deadline season and exams approaching, it’ll do you better to get some sleep than staying in the library all night - a library desk is not a substitute for your bed. Not a good one, anyway.