“There is a time for many words, and there is also a time for sleep.” Homer, The Odyssey
Pulling an ‘all-nighter’
On several occasions over the years, I have decided to ‘pull an all-nighter’ and stay up to study for an exam the following day. On some occasions, it was because of a lack of preparedness or anxiety, sometimes, it was due to peer pressure with flatmates doing the same, but on every occasion, it was both unnecessary and counterproductive.
During my years working as a junior doctor, sleep became a luxury, and I experienced great difficulty balancing my work commitments, social life, hobbies and exam preparation. I often got by on 5 hours of sleep or less but started to notice that my ability to learn and performance was suffering as a consequence.
Studies by the Division of Sleep Medicine at Harvard Medical School have shown that the short-term gains from sleeping less are heavily outweighed by the detrimental effects of sleep deprivation. Most people require between 7-9 hours of sleep to be sufficiently rested and perform to the best of their potential.
Why do we need sleep to learn?
The cognitive effects of sleep deprivation are far-reaching, and it is known to adversely affect brain function in a number of different ways. A variety of different studies have linked sleep deprivation with irritability, mood changes, impaired judgment, increased stress, decreased creativity and even symptoms of attention deficit hyperactivity disorder.
It has long been recognised that sleep and memory are closely interlinked. Memory formation has been shown to be both enhanced and stabilised by sleep. Different phases of the sleep cycle are associated with different types of memory formation, but Rapid Eye Movement (REM) sleep that occurs in the later stages of the sleep cycle, usually between 6 and 8 hours, is very important for people that are currently attempting to learn new facts. During the REM stage of sleep, the brain is processing the previous day, removing unnecessary details and consolidating new knowledge that has been learned. If you sleep too little, not enough time will be spent in REM sleep, and the learning process will suffer as a consequence.
In addition to this, recent work by the Sleep and Neurophysiology Laboratory at the University of Rochester has shown that sleep has an even more vital function. This research showed that there are numerous toxins released by the central nervous system as a consequence of neural activity that occurs whilst awake. These toxins are processed and removed from the brain whilst we are asleep. If these toxins are not removed, it is thought that they can impair our higher functioning and learning capabilities. Furthermore, it has been postulated that sleep deprivation may increase the risk of neurological diseases, such as Alzheimer’s disease, due to a build-up of these toxins.
What else does sleep deprivation do?
During many stages of my life, I have experienced disturbed sleep patterns and difficulty sleeping. Shift patterns and working on-call as a junior doctor certainly contributed to this. On many occasions, when working prolonged runs of night shifts, my body clock became so confused that I had difficulty sleeping more than two or three hours at a stretch. This also corresponded with the period in my life when I was most active academically and sat a number of important postgraduate exams.
The irregularity of working night shifts and doing on-calls caused me to often feel exhausted at work and then be unable to sleep during the day. Trying to re-organise my sleep pattern following nights became a crucially important part of my exam preparation, and I learned many important lessons about ‘sleep hygiene’ along the way. Sleep hygiene is a set of different practices that help to promote good quality sleep and daytime alertness.
Dealing with night shifts
During many stages of my life I have experience disturbed sleep patterns and difficulty sleeping. Shift patterns and working on-call as a junior doctor certainly contributed to this. On many occasions when working prolonged runs of night shifts my body clock became so confused that I had difficulty sleeping more that two or three hours at a stretch. This also corresponded with the period in my life when I was most active academically and sat a number of important postgraduate exams.
The irregularity of working night shifts and doing on-calls caused me to often feel exhausted at work and then be unable to sleep during the day. Trying to re-organize my sleep pattern following nights became a crucially important part of my exam preparation and I learned many important lessons about ‘sleep hygiene’ along the way. Sleep hygiene is a set of different practices that help to promote good quality sleep and daytime alertness.
Improving sleep hygiene
One of the best ways to ensure adequate sleep whilst on night shifts is to eliminate all noise and light from your sleep environment. I had blackout window blinds fitted in my bedroom and would also wear earplugs and a sleep mask.
Melatonin controls our sleep-wake cycle, with the pineal gland starting to produce it in the evening and levels peaking in the middle of the night. Blue light exposure in the morning then suppresses production, and levels remain low until the evening when blue light levels fall, and it becomes dark again. Watching TV or reading from a backlit iPad in the morning when returning home from a night shift will suppress melatonin production and disrupt your sleep pattern further, so try to avoid this if at all possible. An alternative is to wear blue-light blocking glasses in the last hour or two before going to bed. Better still, try listening to an audiobook or some gentle music before going to bed.
It is very tempting to load up with caffeine when working night shifts. This will certainly give you a boost when working on your shift, but caffeine can stay in your system for between 6 and 10 hours. I stopped drinking coffee altogether on night shifts, and it definitely improved my sleep pattern, but if you feel that you must have a cup, try to do it in the first hour or two of your shift only.
Try also to avoid drinking alcohol before you go to sleep. It will certainly make you sleepy initially, but it will reduce your sleep quality and can shorten the period that you sleep for. You are also more likely to feel groggy and be less productive when you do wake up.
It has been shown that people that exercise have better quality sleep, and trying to do some gentle exercise during your night shifts can help facilitate improved sleep. The caveat is that strenuous exercise too close to bedtime can cause increased alertness and delay falling asleep. Try going for a walk or a gentle jog or swim before your shift to see if this helps your sleep when you return home after the shift but avoid exercising when you get home and are preparing for bed.
When all else fails, try to grab a nap whenever you can. If your shift is quiet, try to take it in turns to get a short sleep whilst at work. If you work in a team, try to organise a short sleep break for each member and cover for each other in turns. If it becomes busy or an emergency crops up, it is very easy to be woken up, and you will almost certainly be fresher and more alert to deal with the situation.
Key points to remember:
✅ A good night’s sleep is more important than all-night studying
✅ Sleep deprivation impairs memory formation and cognition
✅ Sleep deprivation is also associated with a wide variety of serious
health conditions
✅ Junior doctor sleep patterns can disrupt sleep patterns severely
✅ Take measures to improve your ‘sleep hygiene’ to improve your
sleep quality
Header image used on licence from Shutterstock
Medical Exam Prep would like to thank Dr. Marc Barton for permission to reproduce this extract from his book ‘How to Pass Medical Exams: A Survival Guide for Medical Students and Doctors’.
About Dr. Marc Barton
Dr. Marc Barton qualified from Imperial College School of Medicine in 2001. Since that time he has worked in a variety of different medical specialities. He worked as a GP partner from 2006 until 2008 and more recently as a higher specialist trainee in Emergency Medicine.
‘How to Pass Medical Exams’ is available for purchase here.
