Knocking off sleep – a complicated relationship between sleep and concussion

Let me begin by stating that I’m not a sleep specialist, and this blog is not a piece of medical advice. What fascinates me the most about sleep is how this state of apparent inactivity holds such sway in our lives. My series The Sleeptime tries to capture the essence of the inquisitiveness that  I have had for a long time and being a neuroscientist now, I try to delve deeper. Today’s blog is set in the backdrop of a childhood experience that has etched a sense of fear regarding falling and sleep.

This experience did not stem from any nightmare, which can be a story for another day, but was something very real. For now, let us travel back to my 6th-grade summer vacation. This was the first time my parents had entrusted me with babysitting my sister. She was 6 months old then — a jolly baby who had recently discovered the thrill of rolling over and attempting to thrust herself forward on her belly in a bid to explore the brave new world. I was extremely excited to have been given the role of a big responsible sister, and I was prepared to take care of her with all enthusiasm.

The first couple of hours were great! I innovated all sorts of games to keep her occupied. However, as time passed, I started feeling exhausted and found it a little difficult to keep with her boundless energy. So, I devised a way to restrict her movement and conserve some of my own energy. The plan was straight forward; I will feed her (as fat babies don’t move much 😉, at least that what I thought), place her on my parents’ high-rise bed, and build a wall of pillows all around her. The success was immediately rewarding- as I relished her failed attempts to climb up the fortification. I was finally rest assured that the victory was mine as I saw her surrendering to sleep. Basking in my own glory, I plugged my headphones on and oblivious to my surroundings, kicked off to play Road Rash.

By now, you must have guessed how this story ends. My sister woke up fresh and even more energetic thanks to the food and the short nap. She re-attempted the cross over and unfortunately, this time was successful. She crashed head first on the floor and suffered a significant concussion, which I realized only after 15 minutes at the end of my triumphant lap. Perplexed by what just happened and terrified by her constant vomiting, I decided to call my neighbor for help. The whole journey to the hospital was a haze for me, but only one statement from my neighbor kept on echoing ‘Do not let her fall asleep, it’s deadly’. Despite my best efforts, I couldn’t keep her awake, and in addition to the concussion, she suffered extreme fatigue on our way to the hospital. Rest of the drama is history, but all is well that ends well as today she is a healthy and vibrant young woman. Nonetheless, this accident still haunts me, and I often wonder about the origin of the notion that dozing off post head injury is detrimental for the patient?

The neuroscience argues (1,2,3) that this could be a myth, and in fact, rest is recommended in the acute stage, immediately following injury – up to 24 to 48 hours – before guided, a gradual return to activity. The longstanding fear was that one wouldn’t wake up if they slept following a concussion. This notion developed due to a misunderstanding of medical terms called ‘’lucid interval’’. In medicine, lucid interval refers to a short time window where the patient wakes up from being unconscious and temporarily everything seems to be improving, but after which the condition deteriorates. A lucid interval, although rare, is especially indicative of an epidural hematoma, where the brain is internally bleeding after a severe head injury. An estimated 20-50% of patients with epidural hematoma experience such a lucid interval, which is a large scary number but not the complete picture.

Sleeping through night after concussion is okay once you receive the green light from your physician. Image credit: UPMC

My sister is one of the lucky ones, but the number of people suffering from post-traumatic head injuries is staggering and goes beyond my personal invested interest in this topic. For example, in the USA alone, there are 1.6-3 million traumatic brain injuries each year, and worldwide it is 69 million. The problem intensifies, not just because the patients potentially could slip into a lucid interval, but also because detection of the exact extent of the damage after a concussion is nearly impossible. To establish the severity of the injury most of the physicians rely on the symptoms such as a loss of balance, blurred vision, tingling in the arms or the legs, vomiting, headaches, and confusion. These are indeed critical indicators, but not all patients are the same and might not even show these symptoms. Therefore, reliable early detection is the key that could help all the patients with concussion.

There is some hope for the future. A simple blood test might be able to detect concussion by measuring specific proteins like Ubiquitin C-Terminal Hydrolase-L1 and Glial Fibrillary Acidic Protein in the bloodstream. In 2014 it was discovered by a team at Orlando Regional Medical Centre in Florida that these two proteins are released by the brain when a blow to the head has caused some damage to it. Admittedly, this test will take a few more years to develop, and in the meantime, doctors will have to rely on the observation of symptoms.

If you are with someone who has a concussion or head injury, there are specific guidelines available from several organizations like World Rugby and Britain’s NHS. However, it is essential to get immediate medical care and watch out for symptoms closely. If someone is not confused or vomiting, or has double vision or trouble walking or a severe head or neck ache, these recommendations do not include the advice to keep them awake. In fact, rest is what’s needed, and the brain needs to heal by not doing too much work. Although it should be highlighted here that until very recently, a few trials have tested this advice and it still worries some researchers. The hope is in the future when we will have the outcome of several new trials underway, and we should soon have better information on the best practices to take care of patients with head injuries.

Surely to recover from a concussion, it requires healthy and adequate sleep. Although, for about 30-70% of patients with mild head injuries, it is not easy. There is a palate of different sleep disorders which are more common in the days and weeks following a concussion. This, in turn, can halt the necessary healing process. A period of depression and anxiety may also follow a head injury, as neuronal damage influences mood and behavior and can further worsen sleeping.

Further research connecting concussions and sleep health has revealed even more complex links. One study found that although the concussed group reported more sleep problems than the healthy group, there were no real differences observed during sleep when both the groups were monitored under a brain scan. Instead, they landed up discovering a vicious cycle. The head injury patients produced more delta waves (associated with deep sleep) and fewer alpha waves (associated with relaxed wakefulness). Suggesting that concussion might create more problems with wakefulness than with sleep itself. These disturbances in wakefulness can, in turn, lead to additional fatigue and sleep problems like insomnia. Moreover, patients with repeated concussions, for example, rugby or football players can lead to chronic traumatic encephalopathy, a neurodegenerative disease that can lead to dementia and causes the same sleep problems as a concussion.

Many rugby or football players suffer from chronic traumatic encephalopathy, upon repeated concussions. Image credit: Pixabay

Clearly, concussions can cause both short-term and long-term disturbances. Therefore, it is essential that patients try and get both mental as well as physical rest to assist them on the road to recovery. They can do this effectively by practicing good sleep hygiene habits, turning off electronics and avoiding mentally taxing activities during the day for a while, and, if needed, taking over-the-counter sleep aids under their physician’s supervision.

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Our collaborators on this article

Illustrator: The cover image is made by a science communicator friend, Ipsa Jain. She uses arts and design to start conversations about science. Ipsawonders is one woman labor of love. She wants to create beautiful things that speak science.

Editor: The article is edited by Rashmi Guha Ray, who is a journalist from India. Her undying passion for politics carried her to the western shores to study MA in Conflict, Governance, and Development in the University of York, UK. She is currently working as a research assistant in a project on migration. A trained editor who is hopelessly in love with words, Rashmi loves taking up new challenges in editing and rewriting and the Serendipity Brain is one of her latest ventures.