What happens in the brain during sleep?

In the first episode of our new video series, the Sleep Wisdom, Dr Rebecca Robbins helps us debunk the myth that during sleep our brains are completely switched off.

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Earlier this summer we launched a new video series, titled the ‘Sleep Wisdom’. Each episode aims to debunk common sleep myths, and bring the science of sleep to the forefront. In our first episode, Sleep Scientist and Sleep Expert to Savoir, Dr Rebecca Robbins, explains what happens to our brains while we sleep. From processing memories to brain detoxification and its importance to our health and well-being. Join us as Dr Robbins uncovers the science of a restorative night’s rest.

It is a myth that during sleep our brain is switched off and resting. Instead, our brain goes in and out of one of four different stages. And in this beautiful, rhythmic fashion.

Dr Rebecca Robbins
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“As we start to enter sleep at night, the pens of the electrodes – if I were measuring you in our sleep laboratory, start to slow. Indicating that our brain is starting to slip into some of the lighter stages of sleep. During the lighter stages of sleep, we’re easily awoken by sounds around us. But as we start to slip into some of the deeper stages of sleep at night, the pens of the electrodes, if we’re monitoring you in the laboratory, start to slow so much, that it sounds as though there is absolutely nothing happening in the brain. Now, this is essential. Because this is where, we as humans, come the closest to hibernation in our typical day.

Then, something fascinating happens. After about 20 minutes from falling asleep, we enter our first rapid eye movement period of the night. This rapid eye movement period lasts for a very short time, but during REM the brain becomes alive. If I were monitoring you in my laboratory, the pens of the electrodes would show enormous activity in the brain. There are very high frequencies that are quick brainwaves, and very low amplitude. That’s the space from peak to trough in a brainwave. Indicating a tremendous amount of activity.

And what’s so fascinating, is that patterns of wakefulness, when we’re learning new activities, in the brain, are actually repeated during sleep

Dr Rebecca Robbins

During this stage of sleep, what’s happening in the brain is we are repeating and rehearsing some of the events from our day before. And what’s so fascinating, is that patterns of wakefulness, when we’re learning new activities, in the brain, are actually repeated during sleep.

So, this stage of sleep is important for our cognitive function, our memory and so many areas of our brain. One of the most fascinating areas of sleep science is indicating that during sleep compared to wakefulness, we experience an accelerated clearance of brain toxins. That clearance happens at about a 60% greater rate during sleep than wakefulness. And that removal of toxic particles is vitally important for us to maintain a healthy brain – today, tomorrow and well into the future.

We see in our epidemiological studies that when we’re not getting enough sleep and getting the benefits of all that clearance of these dangerous brain toxins, over time, we’re at increased risk for Alzheimer’s disease and dementia. So, it is a myth that our brain is switched off and resting during sleep. Instead, we enter and re-enter these different beautiful stages of sleep in a symphonic pattern. And we must hit each note in the symphony of the night to wake up and be at our best.”

Dr Rebecca Robbins

Join us on Instagram and enjoy all episodes of Sleep Wisdom, debunking common sleep myths, discovering the science of sleep and more.

Everything you need to know about insomnia

Introducing our new series, Sleep Matters, where we dive into sleep problems some of you may experience and discover solutions that’ll bring you a lifetime of restorative sleep. In our first issue, we uncover everything you need to know about insomnia and its effects.

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While many elements contribute to enjoying a good night’s rest, for some, there are concerns that good sleep hygiene and bedtime routines simply can’t fix. The effects of inadequate sleep can be detrimental to your health. Affecting next-day performance, causing irritability, and compromising your immune system.

Recent research shows that 10% of the worldwide population struggles with insomnia. Additionally, t’s estimated that 35% of people will experience symptoms of insomnia it at some point in their lifetime. Although for most, these symptoms can ease over time, there are others, who’ll experience long-term effects of the disorder.

To understand more, we sit down with Sleep Expert Dr Rebecca Robbins. And together, we uncover everything you need to know about insomnia, the science behind sleep problems and discover how we can tackle their effects so that we can truly enjoy a restorative night’s rest.

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World's first luxury plant-based bed, The Reformer, made with materials derived from nature and lovingly refined.

According to the American Academy of Sleep Medicine, insomnia is a clinical diagnosis. It’s defined as the subjective perception of difficulty with sleep initiation, duration, consolidation, or quality that occurs despite adequate opportunity for sleep and results in daytime impairment. Insomnia becomes chronic when a person begins having difficulty falling asleep or staying asleep for as little as three nights per week for at least two consecutive weeks up to three months.

“So, if you find it difficult to get the rest you need despite giving yourself sufficient time to sleep, it might be time to speak to a health professional, who can diagnose you.”, advises Dr Robbins.

Savoir: What are the most common causes of insomnia?

Dr Robbins: There are many causes of insomnia, ranging from physical, such as hormonal fluctuations, injuries or pain. Psychological causes such as depression and anxiety, and situational, such as when we experience jetlag.

We all can likely relate to the experience of insomnia symptoms at one time or another in our lives. The truth is, sleep is the result of our waking days. This can include stressful events like frustrating professional or personal experiences. All of these can limit our ability to fall asleep or maintain sleep.

The truth is, sleep is the result of our waking days.

Dr Rebecca Robbins

Is there a link between circadian rhythm and insomnia?

Circadian rhythm disorder symptoms are similar to those of insomnia. They can include difficulty falling, staying asleep or waking up too early.

However, symptoms of the former are due to a disruption in the timing of sleep, which can be caused by irregular sleeping times, inadequate time in the daylight and poor diet. Whereas an individual suffering from insomnia can experience all the symptoms even if they practise healthy sleep hygiene.

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Are there any groups of people who are more likely to be at risk of insomnia?

There are a few groups that are at greater risk of insomnia. Unfortunately, sleep systems decline with age, making it more difficult to fall asleep and consolidate sleep. For these reasons, insomnia is more likely among older adults than younger adults. However, individuals with family history of insomnia and those that are prone to stress and worry are also at greater risk. There are certain medical and psychiatric disorders, such as heart disease, asthma, anxiety, and depression that can make an individual more likely to experience insomnia too.

What are the consequences of untreated insomnia?

Untreated insomnia can present short consequences, including irritability, feelings of anxiety and depression. It can also affect our immune system and increase the risk of colds and flu. There is also research that estimates the costs of untreated insomnia to be as high as $100 billion US dollars per year. This is due to additional healthcare costs, reduced productivity, and accidents.

Concerningly, in the longer term, including increased risk for chronic conditions, such as cardiovascular disease and obesity. There is also evidence that untreated insomnia could place older adults at an increased risk of dementia and Alzheimer’s disease, therefore, underscoring the importance of being treated.

How does insomnia affect our mental and physical well-being?

Those suffering from insomnia can face myriad challenges to their mental and physical well-being and performance. Untreated insomnia presents risks for brain fog and lower productivity, shorter attention span, and less creative problem-solving. An individual may also experience increased feelings of anxiety, which can greatly affect both their personal and professional life.

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Spending time outdoors and getting enough daylight can greatly reduce the risk of symptoms of insomnia.

We’re more aware of our well-being and the importance sleep plays in this. Does this mean there are fewer people suffering from insomnia than before the COVID-19 pandemic?

We do have evidence that symptoms of insomnia increased in prevalence across the globe amidst the COVID-19 pandemic, which was marked by conditions ripe for insomnia, including tremendous uncertainty and unknown.

What can someone do to manage the symptoms of insomnia?

Fortunately, there is a range of treatments for insomnia. These include both pharmacological interventions as well as behavioural treatments. Excitedly, research shows that these two pathways are both highly efficacious for attenuating insomnia symptoms and improving quality of life.

On the behavioural side, the gold standard treatment is called “Cognitive Behavioural Therapy for Insomnia” and includes specific recommendations to help the person suffering from insomnia to reframe how they think about sleep and their bedroom. Another central piece of CBTI is relaxation training and learning meditation and mindfulness exercises to ease tension around bedtime.

Untreated insomnia presents risks for brain fog and lower productivity, shorter attention span, and less creative problem-solving.

Dr Rebecca Robbins

Lastly, are there any precautions we can take to prevent insomnia?

There are a handful of precautions we can all take. Following a healthy diet and exercising regularly can greatly impact an individual’s likelihood to experience insomnia. You should also introduce a consistent sleeping routine, spend an adequate amount of time in the daylight and outdoors and avoid alcohol and caffeine after 2pm.

If the symptoms of insomnia sound like something you are experiencing, we recommend reaching out to a Sleep Specialist, who can assist you further and recommend the right treatment for you.

Dr Robbins is Assistant Professor in Medicine at Harvard Medical School and an Associate Scientist at the Brigham and Women’s Hospital and has been an expert on the science of sleep for Savoir since 2020.

Forget the recommended 8 hours of sleep - focus on quality instead

Join us in conversation with Harvard’s Sleep Scientist, Dr Rebecca Robbins, as she explains why focusing on quality instead of quantity of sleep can have a tremendous effect on our health and overall well-being.

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Forget the eight hours of recommended sleep. Believe it or not, the quality of our sleep is as important, if not more so, than the quantity of sleep that we get.

Dr Rebecca Robbins

Savoir: Firstly, are there any tell-tale signs that we are not achieving quality sleep?

Dr Robbins: Even a well-rested person may experience tiredness in the afternoon. This fatigue is due to a drop in our body temperature between 1-5 pm. This is particularly evident for those not achieving quality sleep. So much so, that they will look for means such as coffee or other stimulants to keep them awake during these hours. And so, a sleep-deprived person will experience significant sluggishness and sleepiness in the afternoon. If you find yourself desperate for stimulants to maintain alertness, it is a sure sign you are not getting enough quality sleep at night.

Furthermore, research has shown that sleep loss reduces your VO2 max, the amount of oxygen your body can absorb during exercise, which fuels your workout. Inadequate sleep leaves us less motivated to exercise and less able to get a good workout when we do exercise.

As well as exercising, sleep can also impact appetite. When we are sleep deprived, the hormones that regulate our appetite are thrown off balance. Specifically, the hormone ‘leptin’ that tells the brain when we have had enough to eat is inhibited. This leaves us less able to understand when we have had enough to eat and therefore prone to overeating. You make may also make worse nutrition choices. When we are well-rested, we are more motivated to eat healthy meals. But when we are sleep-deprived, we are more likely to reach for sugary, carbohydrate-dense foods.

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Difficulty waking up can be a tell-tale sign of poor quality sleep. Dr Robbins explains why focusing on quality of sleep is the key to improving your productivity.

By focusing on getting good quality sleep, we can then focus on the constellation of sleep and things that improve our well-being. And believe it or not, good quality sleep starts as soon as we wake up.

Dr Rebecca Robbins

What role does circadian rhythm play in achieving quality sleep?

Our ability to fall asleep and obtain healthy sleep is, in part, governed by our internal circadian rhythm. This system evolves to understand when we should be alert and when we should be tired. If we keep our bedtimes consistent, our circadian rhythm becomes refined and well ‘trained’ in understanding when we are tired and awake.

If we keep different bed and wake times, then our internal clock is limited in knowing when we should be tired or awake. Leaving us in a constant state of disorientation. This is a recommendation we give our children. We stick to a consistent bedtime routines for them. However, we are guilty of not doing this ourselves. If you keep a consistent sleep schedule, you may find you fall asleep faster and spend less time tossing and turning.

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The Louis bed designed by Francis Sultana and photographed by Michael Sinclair
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Investing in high-quality mattress and bed can greatly improve the quality of your sleep.

Can you share some strategies to achieve quality sleep?

Believe it or not, a good night’s sleep starts when we wake up. If you are struggling with poor-quality sleep, these are my top three considerations. Firstly, try introducing a mindfulness-based practice. Meditation and Breathwork are about being present and at peace in the moment. Giving us the tools needed to control our breathing, which leads to a calmer mind and a relaxed body. These are the essential skills to help us fall asleep. Anyone who struggles to fall asleep and spends time tossing and turning may benefit from starting a mindfulness-based practice.

Secondly, alcohol consumed in small doses may help you fall asleep, but much more than that will dramatically reduce the quality of your sleep. Specifically, alcohol pulls you out of deeper stages of sleep, so that you may spend time sleeping but wake up not feeling refreshed.

And finally, stress is the number one cause of insomnia, and managing our emotions and stress is central to our ability to get healthy, restorative sleep. If you kick off a healthy exercise routine, you may also find you fall asleep faster, for exercise releases endorphins which are mood elevators. Not surprisingly, research shows that those who exercise regularly take less time to fall asleep and obtain more restorative sleep than those who do not.


Discover our latest video series, titled the ‘Sleep Wisdom‘, where Dr Rebecca Robbins helps us debunk common sleep myths, understand the science of sleep and more.

A guide to keeping cool while you sleep

Science indicates that temperature plays an integral role in the quality of your sleep. It’s essential that your body remains within a neutral temperature zone, to enjoy a restful night’s sleep.

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Your body’s ability to regulate temperature is a big part of how it regulates sleep. During REM sleep the brain’s temperature-regulating cells switch off and your temperature is impacted by your bed and sleeping surface. At this stage of the sleep cycle, you may begin to sweat and overheat. If your bed and sleeping surface are unable to breathe and disperse moisture effectively, your body temperature may start to rise. Through keeping cool, sleep disturbances are reduced helping you to achieve a good night’s sleep. 

Natural materials such as wool and horse tail allow the sleeping surface to breathe and wick away moisture. This helps you to maintain an optimal, even temperature throughout the night. Synthetic fibres, such as latex and foams, can cause sweating as they are unable to breathe and tend to retain heat. 

From the perfect bedding for warm nights to a sleeping surface with an abundance of natural materials, we’ve compiled our guide to help you keep cool and enjoy restorative sleep.

In a warm sleep environment, we are more likely to have nightmares. We may also experience sleep fragmentation. So, at night we optimally want to be in a thermal neutral zone, which is on the slightly cooler side.

Dr Rebecca Robbins
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Natural Materials

Choosing natural materials for your bedding and pyjamas will help regulate your body’s temperature, resulting in a deeper, relaxing sleep. Silk, linen, and cashmere are summer-time classics, thanks to their soft and light texture. Whilst wool and horse tail may not spring to mind when it comes to keeping cool, these natural fibres boast wonderful moisture-wicking properties to help regulate your body temperature.

To immediately change to a natural sleeping surface a topper is a great solution. Filled with an abundance of naturally breathable materials, toppers can instantly elevate your summer sleep. A mattress protector is an element of bedding that is often overlooked during the warmer months. However, a climate control mattress protector continues to help breathability, whilst helping to keep the sleeping surface clean and dry. Ours is filled with Tencel fibres which disperse moisture and keep it away from the skin to help combat overheating, allowing you to keep cool. It can also be machine washed to ensure it stays soft and fresh.


Every element of your bedding should help regulate your temperature. If goose down is your preference, choose a lower tog such as 4.5 for during warmer months, and opt for a higher tog in the winter. A natural down duvet controls your body’s temperature wonderfully, making it a great choice all year round.  

An alternative to down is a pure silk duvet. The super soft natural fibres help to efficiently wick moisture away from your skin, preventing you from overheating. Our silk duvet is also encased in a soft Tencel fabric cover, making it perfect for balmy summer nights. 

Ensuring your bedding fits the season is key. Switching your winter bedding to a lighter weight or different material will make a big difference to your sleep in the summer. Whilst upgrading to a higher tog will ensure you’re comfortable during the colder months. 

A good choice of bed linen for the warmer months is percale cotton. High-quality percale combines extra-long staple fibres and high thread count to create the perfect balance of breathability and softness. For an ultra-lightweight and super soft feel, choose Giza cotton, which has the longest and finest fibres available. The Drift collection is available in both a 400 thread count and an ultra-fine Giza 87 cotton. 

Luxuriously cool

Climate Control Mattress Protector StrapsClimate control mattress protector

Luxury Climate Control Mattress Protector

100% Tencel

$151.67 to $330.42 View
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The Drift Pure Cotton Percale Bed Linen Set

400 Thread Count

Oxford, Plain hem
$487.50 to $985.83 View
Duvet - Pure SilkPure Silk Duvet

Luxury Pure Silk Duvet

100% Natural Silk

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Vegan Topper



If the temperature of your bedroom or sleep environment rises above 23.8°C (75°F) it can disturb your sleep and may even wake you. To keep the temperature down on extremely hot days, it may help to reduce the hot air and sunlight that enters the space during the day. By keeping certain doors and windows shut with blinds and curtains closed, to help prevent the room from warming up during the day. When the temperature drops, the evening breeze and cooling night air can then enter the space. 


Cotton pyjamas are a classic bed attire for every season. They offer great breathability and help to combat overheating during warmer weather. If you prefer a softer feel, silk is a wonderful alternative. Super soft on your skin, the natural silk fibres wick away moisture whilst you sleep, maintaining your normal body temperature.

By keeping cool and minimising disturbances you can enjoy a restful night’s sleep, on the warmest and the coldest of nights. 

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Taking time to unwind before bed can have an incredible impact on the quality of your rest, even during the warmest of nights.

Mindful moments

The hours leading up to your bedtime are the most crucial for a restful night’s sleep. Getting into a habit of avoiding technology and blue light will allow your brain to prepare for rest. Meditation and yoga are also proven to help us relax and put our mind at ease. And if you need some extra help, try burning essential oils to create a calming atmosphere in your bedroom.

There are specific natural fragrances that when burned can help improve air quality. Eucalyptus is especially great during the summer months, as it is known to open up air pathways and cleanse high traffic spaces, which is especially helpful for those struggling with seasonal allergies and hay fever.

And lastly, if you find yourself tossing and turning, allow yourself to reset by leaving your bed completely for at least 15 minutes. In that time focus on a very simple, relaxing task like reading a few pages from your favourite book or doing a gentle stretch. This will stop you from associating your bed with restlessness and unwanted thoughts, and instead will help your mind perceive it again as a peaceful place of rest.