The Matt Walker Podcast

Matt dives deep into the science of memory with renowned neuroscientist Dr. Charan Ranganath, author of Why We Remember: Unlocking Memory's Power to Hold On to What Matters in today’s episode. Together, they explore the complex relationship between memory and the brain, touching on the roles of emotional significance, context, and even neuromodulators like dopamine in helping our brains decide which memories to retain and which to discard. Dr. Ranganath shares his unique journey into mem...

In Matt’s latest installment of his "Ask Me Anything" series, he once again joins forces with Dr. Eti Ben Simon to address a wide spectrum of listener questions. Beginning with a dive into the fascinating connections between sleep and medication effects, they unpack the ways various medications can impact sleep quality and patterns, from increasing alertness to potentially triggering vivid dreams or insomnia. Eti also brings a unique perspective on how different medications influence REM slee...

Matt returns this week to unpack the complexities of narcolepsy, a neurological sleep disorder often misunderstood and misdiagnosed. He starts by defining narcolepsy, explaining its profound impact on brain and body functioning and its chronic nature, which often diminishes patients' quality of life. Narcolepsy affects about 1 in every 2,000 people, yet most go undiagnosed due to limited awareness and medical training on sleep disorders. With a closer look at the causes, Matt explores how the...

Matt revisits the concept of "sleep divorce," or "sleep separation" in this latest episode, examining its effects on relationships and well-being. He cites studies showing that up to one in four couples in the U.S. and U.K. sleep in separate rooms, a statistic often underestimated due to stigma. While many fear that sleeping apart harms intimacy, Matt presents data indicating that it can actually enhance sleep quality and intimacy by promoting better-rested bodies and increasing hormones like...

Matt and Eti return today for another AMA session where they dive into even more fascinating and often quirky sleep questions that have been submitted by listeners. In this installment, our duo explores the evolutionary puzzle of why we sleep, despite the apparent risks it poses for survival. They also share insights into how early organisms, like earthworms, exhibit sleep-like states, which raises the question: did wakefulness evolve from sleep?As the episode continues, the pair tackle pract...

Matt Walker welcomes Dr. Jessica Lunsford-Avery, an Associate Professor in Psychiatry and Behavioral Sciences at Duke University to the podcast today. Dr. Lunsford-Avery, a clinical psychologist, delves into the crucial link between sleep and mental health in children with ADHD. Her groundbreaking research explores how sleep impacts daytime impairment in ADHD, focusing on cognitive behavioral therapies to improve both sleep quality and ADHD symptoms. Their discussion highlights the critical n...

Dr. William “Bill” Jagust, renowned expert in brain science and Alzheimer’s research - and one of the reasons Matt chose to move to UC Berkeley - joins our host today for an in-depth discussion on aging, cognitive decline, and the critical role of neuroimaging, with some sleep talk woven in as well. Dr. Jagust shares groundbreaking insights into how PET scans can detect amyloid and tau proteins in the brain—two key contributors to Alzheimer’s disease—years before symptoms emerge. Together wit...

In this latest AMA episode, Matt and Eti are back to tackle listener questions about naps and sleepwalking this time around. They begin by delving into the intricacies of power naps and their impact on brain function and sleep health, and go on to discuss the optimal timing and duration for naps, emphasizing that a balance between benefits and drawbacks is crucial. Shorter naps of 10-20 minutes are highlighted for their ability to boost alertness and focus with minimal sleep inertia. Con...

Dr. Wendy Troxel returns to the podcast today to discuss the significant impact of sleep on relationships and mental health with Matt. Offering actionable strategies for couples facing inevitable sleep disruptions, Dr. Troxel emphasizes the importance of communication, suggesting that couples anticipate sleep challenges, share responsibilities, and use tools like the "slangry" label to recognize and manage sleep-deprived behaviors. She also highlights the importance of timing conversations an...

This week, Matt shines his spotlight on the intriguing topic of melatonin use for individuals living with autism spectrum disorder (ASD). While melatonin has been discussed in previous episodes in relation to sleep enhancement and antioxidant properties, today's focus is on a recent meta-analysis that examines its effectiveness in treating sleep disorders specifically in those with ASD. This deep dive is prompted by new data and the pervasive sleep challenges faced by individuals with autism,...

In yet another informative and entertaining AMA episode, Matt and Doctor Eti Ben-Simon delve into the variety of sleep-related questions uppermost in listeners’ minds . Matt begins by explaining that THC, the main psychoactive component in cannabis, can help individuals fall asleep initially but disrupts sleep patterns and circadian rhythms with chronic use. This can lead to increased brain temperature, tolerance, dependence, and decreased REM sleep, impacting emotional regulation and overall...

The Science of Shared Sleep: Dr. Wendy Troxel on Bedtime and RelationshipsThis week, Matt is joined by Dr. Wendy Troxel the celebrated sleep and behavioral scientist whose book, Sharing the Covers: Every Couple's Guide to Better Sleep, highlights the significant impact of sleep on relationships. Revealing that 61% of adults sleep with a partner, Dr. Troxel emphasizes the often-overlooked social aspect of sleep and its implications for couple dynamics. As she notes, sleep arrangements have his...

Matt and Dr. Eti Ben Simon are back today to answer more of your excellent questions with their latest AMA installment - #8!They begin by delving into the intriguing world of lucid dreaming, explaining how it enables dreamers to become aware and even control their dreams, and move on to discussing the scientific methods used to study lucid dreaming, such as using eye movements as a form of Morse code to communicate with researchers. Through studies involving MRI scans, scientists have validat...

Matt continues his series on the impact of cannabis, THC, and CBD upon sleep this week with an examination into the intricacies of cannabidiol (CBD), which, unlike its psychoactive counterpart THC, does not induce a high but is recognized for its potential therapeutic effects. While studies suggest that CBD may aid in alleviating anxiety, movement disorders, pain, and addiction, in this episode, our host focuses on exploring CBD's potential influence on sleep quality while examining its bioch...

In this week’s intriguing episode, Matt delves into the topic of precognitive dreams, exploring the idea that some people can predict future events through their dreams. He explains that while this concept might seem appealing, it is actually a result of statistical chance. With around 8 billion people in the world each having multiple dreams per night, the sheer number of dreams increases the likelihood of coincidental matches between dreams and real-life events. Matt also discusses a g...

In this 7th installment of their AMA series, Matt Walker and Dr. Eti Ben Simon dive into strategies for improving deep non-REM sleep. They highlight the benefits of vigorous exercise, citing a study by Kaspar Vogt that shows how exercise enhances the quality and stability of deep sleep. Additionally, they discuss how temperature manipulations, like using high heat capacity mattresses, can also improve sleep quality. Interesting insights include findings that intense exercise can improve deep ...

Dr. Chris Barnes, renowned Michael G. Foster Endowed Professor of Management at the Foster School of Business, University of Washington, returns to the podcast today to continue his discussion with Matt regarding sleep's impact on business productivity. This time around, Dr. Barnes shares research indicating that sleep-deprived leaders exhibit abusive supervision, reducing employee engagement and productivity. Exploring sleep's broader implications on corporate culture and economic perfo...

Matt continues his exploration into the intricate link between cannabis and sleep, focusing on THC in this second installment, beginning with a reminder to listeners of the historical insights from doctors like O'Shaughnessy and Clendinning in the 1800s regarding cannabis's sleep-inducing effects. He shifts to how THC affects sleep today, noting that while it initially reduces sleep onset time and early night awakenings, chronic use worsens sleep quality, leading to frequent disruptions, espe...

Matt and Eti team up again today for another entertaining and informative AMA episode. This time around, they dive into the intriguing world of lunar cycles and their potential influence on sleep patterns and dreams. From ancient beliefs to modern scientific findings, our duo unpacks the subtle yet fascinating impact of the moon. They then go on to explore the calming effects of weighted blankets on children and adults alike, revealing how deep touch pressure therapy enhances sleep quality an...

Dr. Chris Barnes from the University of Washington's Foster School of Business joins Matt to discuss the often overlooked importance of sleep in boosting workplace productivity and ethical decision-making. Together, they delve into how sleep deprivation affects job performance, the impact sufficient sleep has on business environments and organizational success, and the hidden costs of sleep loss.Dr. Barnes presents compelling evidence on how businesses can use sleep as a strategic asset to cr...

Matt introduces his series examining the complex relationship between sleep and cannabis, exploring both the historical context and contemporary scientific perspectives. The narrative begins with Dr. W.B. O'Shaughnessy's canine experiments in 1849, tracing the evolution to the foundational work on cannabis for sleep conducted by Drs. Clendinning and Bradbury. Despite anecdotal reports suggesting cannabis enhances sleep, the scenario is complicated by factors such as regulatory constraints, va...

This week, Matt dives deep into the complexities of REM Sleep Behavior Disorder (RBD), a condition where individuals physically act out their dreams due to the absence of normal muscle paralysis during REM sleep. He meticulously breaks down the mechanisms of normal REM sleep, where the brainstem induces muscle atonia to prevent dream enactment, contrasting it with the failure of this system in RBD cases. Further expanding on the topic, Matt explores the etiology, diagnosis, treatment opt...

Eti is back for another AMA episode with Matt to answer questions that have been submitted over the last little while. Today’s installment dives into a number of topics including the intricate relationship between sleep and pregnancy, exploring how sleep disturbances impact pregnant women and the postnatal period. Additionally, the hormone prolactin, essential for milk production, is highlighted for its sleep-promoting benefits during the postnatal phase, illustrating nature's intricate balan...

In today's podcast episode, Matt welcomes back Dr. Michael Gradisar to delve into the evolving understanding of screens and sleep. Initially holding the belief in the detrimental effect of screen light on sleep, Matt finds this notion challenged by Dr. Gradisar's research, which emphasizes a more nuanced perspective. Their discussion highlights the shift from simplistic concerns about screen use to acknowledging the multifaceted influences on sleep, including content and individual difference...

Matt explores menopause and sleep disturbances today, noting the impact of hormonal changes, including a drop in estrogen and progesterone, and the role of hot flashes in disturbed sleep. He enumerates different types of sleep impairments related to menopause such as insomnia, sleep-disordered breathing, restless leg syndrome, and various sleep stage disruptions. Treatment options are discussed, with an emphasis on hormone replacement therapy, though controversy surrounding this approach is a...

It’s another AMA episode and Dr. Eti Ben Simon returns to not only share some of her own sleep routines, but also to help listeners gain a rare insight into Matt's personal sleep habits as they respond to a listener’s query. Renowned for not sharing much, if anything, regarding what he considers his “boring” self, Matt is coaxed into offering a candid exploration of his bedtime routines, shedding light on both his successes and challenges in achieving optimal rest. From his dedication to regu...

Matt Walker welcomes his dear friend, the epic sleep researcher and clinician, Dr. Michael Gradisar, to the podcast to join him in exploring the profound influence of light on sleep quality. Dr. Gradisar's groundbreaking research and clinical proficiency in pediatric sleep disorders and circadian rhythm disruptions have reshaped the field, guiding both scientific comprehension and practical interventions. His conversation with Matt here today delves into the intricate interplay among light ex...

This week, Matt explores the intricate connection between sleep and weight, shedding light on the alarming reality of how inadequate sleep contributes to weight gain. He emphasizes the staggering correlation between the rise in obesity rates and the decline in sleep duration over the past six decades, backed by meta-analyses showcasing the significant associations between insufficient sleep and heightened obesity risk. Our host delves into experimental studies revealing how sleep deprivation ...

Dr. Eti Ben Simone is back with Matt Walker to delve into a range of intriguing topics surrounding sleep, circadian rhythms, and the impact of shift work on our health, all within the engaging context of today’s installment of their increasingly popular Ask Me Anything (AMA) sessions. Their conversation begins by exploring the intriguing link between the APOEε4 genotype and sleep disturbances, particularly concerning Alzheimer's disease. It's noteworthy that individuals carrying the APOEε4 va...

Matt’s back this week to delve into the intriguing phenomenon known as Exploding Head Syndrome (EHS). A genuine and significant sleep disorder, EHS is part of the broader category of parasomnias, which includes various sleep-related disorders like night terrors and sleepwalking. The core experience of EHS involves patients perceiving sudden, loud, and shocking noises, akin to explosions or gunshots, as they are either falling asleep or waking up from sleep. These hallucinations are distressin...

In this second installment of their fascinating conversation together, Matt Walker and Michael Grandner continue their discussion regarding the crucial role of sleep in the lives of athletes. Together they delve into the unique challenges athletes face, such as irregular schedules, early mornings, late-night competitions, and travel across time zones, all of which can disrupt their sleep patterns. Dr. Grandner emphasizes the need for athletes to "bank sleep" by ensuring they get sufficie...

In this week’s episode, Dr. Michael Grandner joins Matt to explore the critical role of sleep in athletic performance. Together, they emphasize that sleep is not just about physical rest but also plays a significant role in mental performance, decision-making, and motivation.Dr. Grandner discusses how sleep is essential for various aspects of athletic success, including physical performance, mental performance, recovery, and mental health. He highlights that sleep isn't just a passive activit...

In this podcast, Matt explores the fascinating topic of yawning. He begins by pointing out that although we all yawn and assume it's a sign of sleepiness, science hasn't provided a definitive answer regarding its purpose. Matt delves into the etymology of the word "yawn" and describes the five distinct steps involved in the yawning reflex, shedding light on its physiological process.Matt then introduces three leading scientific theories explaining why we yawn. The first theory suggests that y...

Matt's back, and this time he's tackling the perennial debate: Is the snooze button a friend or foe when it comes to your sleep and overall health? He shines a spotlight on an intriguing study led by Dr. Tina Sundelin and her team - one that challenges our conventional wisdom about snooze buttons. Surprisingly, their research reveals that snooze button usage is quite common, especially among night owls and younger folks. What's even more unexpected is that snoozing may not have the detrimenta...

Dr. Eti Ben Simon joins Matt once again this week to continue their AMA session where they bring their vast amount of knowledge and expertise to bear in responding to a variety of listener questions. They begin by delving into the intricate relationship between sleep, hormones, and the female reproductive cycle, providing invaluable insights into women's health. Together, they examine the challenges faced during the perimenopausal and menopausal periods, characterized by erratic hormonal fluc...

In today’s thoroughly engaging episode, Matt joins forces with Dr. Eti Ben Simon from his Center for Human Sleep Science to embark upon an enlightening "Ask Me Anything" (AMA) session, addressing a wide array of questions related to sleep. Together, they explore such topics as sleep differences between males and females, the impact of sleep trackers on our rest, and the intriguing dynamics of sleep patterns based on biological sex. The journey continues as Matt responds to queries regard...

In today’s memorable episode, Matt examines the intriguing connection between sleep and motor memory. Beginning with an explanation of the two main types of human memory - fact-based memory and procedural memory, which includes motor/skill memories - he notes that, contrary to popular belief, motor/skill memories aren't stored in our muscles but primarily within the brain. Matt also describes his journey into researching motor memories which started at Queen's Medical Centre in Nottingham, En...

In this episode, Matt delves into the intriguing realm of the "caffeine nap." He explores the idea of combining a short nap with caffeine to enhance mental performance and wakefulness. The episode kicks off with a dilemma – in the afternoon, when faced with fatigue, should you opt for coffee or a nap? Matt reveals that the answer isn't a simple choice between the two but a potent mix of both.Matt elucidates the science behind the caffeine nap, emphasizing the ideal timing for each element. He...

In this engaging podcast episode, Matt delves into the world of polyphasic sleep – the practice of dividing sleep into multiple short naps throughout the day. The episode starts by exploring the historical origins of polyphasic sleep, from the concept of phases within a 24-hour sleep cycle to the motivations behind adopting unconventional sleep patterns for increased productivity.Matt explains various polyphasic sleep schedules, such as the Uberman, Everyman, and Triphasic schedules, which in...

Matt and special guest, Dr. Michael Grandner, continue their dialogue regarding the multifaceted world of sleep, insomnia, and their intersections with various life aspects. Together, they unveil the gender-based variations in susceptibility to insomnia, attributing higher rates among women to their willingness to express challenges. Their conversation navigates through sleep difficulties during life transitions like menopause, exploring the impact of physical discomfort and emotional changes...

In the podcast, sleep expert Dr. Michael Grandner engages in a conversation with Matt about insomnia. They delve into the subject by defining what insomnia is, examining its causes, understanding its implications, and discussing potential remedies. An important distinction is made between short-term insomnia and chronic insomnia. They highlight that chronic insomnia often evolves into a standalone problem.One of the major talking points is the significant impact of insomnia, which is believed...

In today’s episode, Matt shines a spotlight on the science behind napping and explores the optimal nap duration for various cognitive benefits. He starts by introducing the concept of napping and its benefits for the brain and body, and then discusses sleep inertia, the groggy feeling upon awakening from a nap, and its potential impact on brain performance.Matt walks through the dose-response curve of naps, starting with ultra-short power naps of five minutes or less, which show no evidence o...

In this second part of his series on sleep, free radicals, and antioxidants, Matt delves into the fascinating connection between sleep and oxidative stress. He begins by recapping the previous episode's discussion on free radicals and oxidative stress, highlighting the recent studies that have revealed one of the functions of sleep: to counteract the harmful effects of free radicals. Curiosity leads Matt to question why total sleep deprivation often leads to death in different species wi...

In today’s episode, Matt takes us on a journey exploring the fascinating world of antioxidants and their link to sleep. The theory of free radical flux and its connection to sleep is introduced, shedding light on the role of antioxidants in combating oxidative stress. Through engaging storytelling and scientific evidence, Matt explains how free radicals can cause cellular damage and why sleep evolved as a mechanism to manage their burden. The research on mutant fruit flies reveals the impact ...

On today’s episode, Matt discusses the concept of "catch-up sleep" and explores whether it effectively compensates for sleep deprivation during the week. The study featured in the episode focused on a group of participants who experienced short sleep during the week and attempted to make up for it with longer sleep on weekends. The findings revealed that despite the extra sleep on weekends, individuals were only able to recover 25% of their sleep debt. This highlights that sleep doesn't work ...

MW E50 Restless Leg SyndromeSummary:Restless Leg Syndrome (RLS) is a neurological condition characterized by irresistible urges to move the muscles in the legs and arms, often accompanied by crawling, tingling, or burning sensations. A common sleep disorder affecting around 5% of the population, which translates to approximately 400 million individuals worldwide, its symptoms primarily occur at night, disrupting sleep quality and leading to fatigue.RLS is linked to genetic factors and i...

Today, Matt explores the fascinating realm of nightmares and the cutting-edge treatment known as Image Rehearsal Therapy (IRT). Nightmares, often associated with rapid eye movement sleep (REM sleep), can disrupt sleep quality and emotional well-being. However, IRT offers a unique approach to tackling nightmares by helping individuals envision alternative endings to their recurring dreams. By modifying and rehearsing these alternative scenarios, individuals can update their nightmare memories ...

In today’s episode, Matt discusses the sleep disorder known as sleep apnea, focusing on its definition, prevalence, and the dangers it poses if left untreated. Sleep apnea is a breathing-related sleep disorder, with obstructive sleep apnea being the most common form. It occurs when the airway partially or fully collapses during sleep, leading to disrupted breathing and oxygen deprivation. Sleep apnea is alarmingly prevalent, affecting an estimated 12-20% of the population worldwide, with a hi...

This week, Matt introduces a new segment called "Hot Off the Press," where he covers the latest and most exciting studies in sleep science. And the topic of discussion for this first installment is a great one: excessive slumber - exploring the questions of whether one is getting enough sleep and if there is such a thing as too much sleep. Listen in today to find out if too much sleep can be harmful in the same way that too little sleep is, whether or not there may be an upper limit to the be...

Matt returns with Dr. Craig Kanapari to discuss sleep in teens and how biological and hormonal changes occur at a young age, usually around 11-13. The most clear determinant of sleep duration in a teen is wake time, and enforcing a wake time inappropriate to the teen's natural sleep period can lead to insomnia-like symptoms and create conflict. The single greatest threat to a teen's sleep schedule is early high school start times. California recently signed a law to address this, and ot...

Today Matt’s discussion with Dr. Craig Canapari continues, delving into the major changes in sleep that a child will go through from the ages of one to ten. This includes how regularity and appropriate sleep opportunities are important for getting good sleep, and potential medical issues that can arise from not getting enough sleep, such as snoring and restless leg disorder. They also discuss when during child development it can be wise to reduce napping and switch to monophasic (single...

Today Matt’s discussion with Dr. Craig Canapari continues, as they delve into the science behind sleep training. Together they cover what it is and when it may be an appropriate technique. Dr. Craig Canipari provides an overview of the different methods of sleep training - ranging from simple bedtime routines, to extinction (also known as cry it out) - as well as some of the historical context behind the technique, and also the controversies and alternatives. It is such a personal...

Today Matt begins a new series all about sleep in infants, in kids, in teenagers, and in parents. He is joined by Dr. Craig Canapari one of the world leaders in pediatric sleep medicine. Dr. Canapari has also written a fantastic book on sleep for babies, kids and parents called, It's Never Too Late to Sleep Train. Enjoy the first episode in a new series, with some show highlights below! Please note that Matt is not a medical doctor, and none of the content in this podcast should be...

On today’s episode, Matt goes beyond the if and the what type of exercise to discuss the when. Which is to say, does the timing of exercise matter when it comes to sleep improvements? Based on his experience working on insomnia, Matt would previously have recommended avoiding mid-to-late evening exercise as the resulting rise in core temperature could harm your chances for good sleep. However, it’s since been discovered that the evidence is quite the contrary, mostly allowing us to abandon th...

Today, Matt focuses on how the type, intensity, and duration of exercise affect its impact on sleep. A study of middle-aged adults split its active group into three subgroups: moderate-intensity aerobic exercise, high-intensity aerobic exercise, and moderate-to-intense weight/resistance training. The groups performing aerobic exercise got more beneficial sleep effects, while surprisingly, the greatest improvement was in the moderate rather than the high-intensity group. These findings replica...

This week, Matt goes deeper into the relationship between sleep and exercise. More specifically, does daytime exercise change the stages and types of sleep? Deep sleep is critical for various functions, so anything that can increase it is desirable. Older adults have an inherently difficult time generating deep non-REM sleep; however, a study showed that the amount can shoot up by 40% following a day with modest exercise. Moreover, it indicated that participants’ cognitive functioning was sig...

Does exercise have an impact on the quantity and quality of your sleep? The National Sleep Foundation's annual poll found that individuals who exercised frequently (defined as three times or more a week) reported sleeping with a higher quality than those who exercised less than once a week. Exercise has also been shown to increase the release of endorphins, which can improve mood and promote feelings of relaxation, both of which can contribute to better sleep.As with most things, modera...

Almost every species will suffer catastrophic impairment in the brain and body due to total or chronic partial long-term sleep loss—save for a small handful of befuddling cases where lack of sleep does not cause devastating impairment. While humans are the only species that deprives itself of sleep for no adaptive benefit, there are rare situations where an animal will limit or go completely without sleep. Starvation pushes aside an organism’s need for sleep to forage more widely, while the n...

The final installment of this series focuses on what happens inside your brain during deep, non-REM sleep that allows you to fixate new memories. There are at least two mechanisms at work here. One is a process of shifting information from short to long-term memory. Each night when you go into deep non REM sleep, those long range brainwaves of deep sleep are going to be moving packets of information, from that short term, vulnerable, USB stick-like memory reservoir (the hippocampus) to the sa...

Previously, we learned sleep is necessary before learning to prepare the brain to learn effectively. But sleep is also needed after learning to cement new information in your brain. This discovery happened in 1924 when two German researchers pitted sleep and wake against each other to see which would win out in memory-savings benefit. Their findings suggested that time spent awake can be hazardous to new memories while time spent asleep has fixating benefits.Researchers have also put REM slee...

It is a fundamental truth that sleep is far more than the absence of wakefulness. It is an incredibly active state, demonstrated by the fact that numerous functions of the brain and body are restored by and depend on sufficient sleep. One of the most impressive and best-understood of these is sleep’s beneficial role in boosting learning and memory abilities. Sleep is necessary both before and after learning and it intelligently associates and interconnects new memories together, offering the ...

It’s been said that sleep is the new sex, and rightly so—a good night of sleep is going to do many things for the vibrancy, intimacy, and vitality of your relationship. We know that when couples are not getting sufficient sleep, they have more conflicts the next day and won’t resolve them nearly as well. This is partly because underslept couples suffer a loss of empathy for each other.However, insufficient sleep also has an effect on sex itself. Specifically, your reproductive hormones suffer...

A few years ago, a survey by the Sleep Council in England found that 1 in 4 people in a couple would get up during the night and go to another room to get a good night’s sleep. Following that, a report by the National Sleep Foundation in America demonstrated that almost the same number (25%) of couples admitted to sleeping in separate bedrooms. In fact, a more recent anonymous survey found that 30%-40% of couples sleep in different beds. Part of the societal stigma (and anxiety for indiv...

Cognitive Behavioral Therapy for Insomnia (CBTI) can be split into at least five core components: 1) sleep restriction therapy, 2) sleep hygiene, 3) stimulus control, 4) cognitive restructuring, and 5) relaxation therapies. Sleep restriction therapy has been shown to be one of the most effective components of CBTI. It isn’t about restricting your sleep so much as limiting the amount of time you are allowed to spend in bed, and it aims to drive up the brain’s appetite for sleep, and...

Very understandably, many insomnia patients try to self-medicate their condition with varied “sleep aids”. The tragedy us that most of them not only fail to help but actually make insomnia worse. Most common among these is alcohol, which hurts your sleep in at least three different ways: 1) it sedates your brain, rather than generating naturalistic sleep 2) it increases the frequency of nighttime awakenings and makes it harder to fall back to sleep, and 3) it inhibits REM sleep.THC also...

Some of the first neurological-related discoveries about insomnia were made by placing healthy sleepers or patients with insomnia inside brain scanners, and measuring changes in the activity in different parts of the brain as they tried to fall asleep. In the good sleepers, three main regions of the brain started to shut down at sleep: 1) emotion-related regions, 2) basic alertness-generating regions, and 3) the sensory awareness gate of the brain.There were also changes in the functional con...

Today’s episode focuses on changes within the bodies of people suffering from insomnia. Almost all forms of chronic insomnia come with a significant psychological component, namely emotional distress and anxiety. This starts a Rolodex of anxiety spinning once you turn off the lights. This leads to rumination and catastrophizing, which will thwart any hopes of a good night’s sleep.Since psychological stress is one of the principal triggers of chronic primary insomnia, researchers went in searc...

Today’s episode takes two questions as its subject: first, why does someone develop insomnia, and second, what adds gasoline to the sleep-disorder fire of insomnia and only makes it rage more powerfully? These are two very complex questions, but through lots of great science and wonderful scientists, we now have a conceptual model explaining how you may find yourself falling into the pit of insomnia. This is called the “3-Ps” model, and it consists of a three-step knock-on cascade of factors ...

There is no quick test that can determine insomnia. Instead, the diagnosis of clinical insomnia disorder is based on a set of clinical assessment and interviews. These center on three core features: 1) difficulties falling asleep, 2) difficulty staying asleep, or 3) waking up and not feeling refreshed by your sleep. Furthermore, to receive the diagnosis, you often have to be experiencing these things at least three nights per week; and having these issues for three straight months.One m...

Today’s episode is the first in a 7-part series on insomnia. Matt starts with a calming reality—insomnia isn’t a single bad night or a string of bad nights of sleep. In the US, epidemiological studies have suggested that insomnia disorder is as prevalent as the obesity epidemic: around 10-15% of the population suffer from clinical-grade insomnia, making it the most common sleep disorder. Indeed, one out of every two people will experience insomnia during their lifetime. It is therefore very l...

Today’s episode focuses on optimising your sleep. It’s designed for people who don’t have clinical insomnia but would like to fine-tune their sleep. Matt goes over five conventional tips, and five unconventional tips that may be new to you. The first tip is regularity—going to bed and waking up at the same time every day. Your brain has its own master 24-hour clock, the suprachiasmatic nucleus, which expects regularity. Second is temperature—your brain and body need to drop their te...

Matt is back this week with his recurring series, ‘Sleep is Bloody Remarkable’. Today’s episode is all about why we are unique when it comes to sleep. When we compare our sleep to that of all other primates, humans stand out in two ways. First, we spend far less time asleep, and second, and in bloody remarkable 😂 contrast, humans get more than double the amount of REM sleep.Unlike many other primates, we humans are exclusively ground (or bed!) sleepers. In contrast, primates usually slee...

In this episode, Matt goes deeper into his exploration of lucid dreaming. He tells us all about studies demonstrating that lucid dreamers can wake from dream sleep on command, demonstrating control over intention in their dreams, and even bring themselves to orgasm in dream sleep!Matt tells us about two leading methods for developing the skill of lucid dreaming. The first is Mnemonic Induction of Lucid Dreams, which involves the creation of a conscious, deliberate intention to remember ...

In part five of his series on dreams, Matt discusses what lucid dreaming is and how it was scientifically proven to be real.We define lucid dreaming as the moment when an individual becomes aware they are dreaming. Historically, the concept of lucid dreaming was considered a scientific scam. First, to claim that people can gain conscious control over a normally unconscious process injects a heavy dose of ludicrous into the already preposterous experience we call dreaming. Second, how could an...

Today’s episode focuses on a second but very different function of dreaming: the ingenious processing and interconnection of memories that inspires creativity and even problem-solving ability.Matt describes how we can think of REM sleep dreaming as a form of informational alchemy, in which we build new connections. As a consequence, we wake the next morning with a mind-wide web of associations capable of divining solutions to previously impenetrable problems.A great illustration of dream-insp...

Matt’s back with part three of his series on the science of dreaming! In this episode, he discusses how he and other scientists have discovered that dreams are not simply an unintended by-product of REM sleep. Instead, dreams provide at least two essential benefits for human beings.The first of these functions involves nursing our emotional and mental health and is the focus of this episode. Matt helps us understand that what makes a memory emotional is that, at the time of the experien...

In the second episode of this series about REM sleep dreaming, Matt explores what the science has to say not only about how we dream at the brain level, but what it is that we dream about. Traditionally, civilizations such as those in ancient Egypt, believed that dreams were a form of divine intervention--a message from the heavens. Thereafter, Matt discusses Sigmund Freud, who introduced the notion of dreams originating from within the brain, not the heavens, and thus could be consider...

This week’s episode is the first in a new multi-part series all about dreams! Today, Matt focuses on the question of how your brain generates these things called dreams.Matt starts with an unexpected statement: last night, when you were dreaming, you became psychotic. 5 things happen when you dream that justify his diagnosis: 1) you see things that aren’t there, 2) you believe things that could not be true, 3) you become confused about time, place, and person, 4) you have wildly fluctua...

Matt has a special announcement this week: a new recurring type of episode called, ‘Sleep is Bloody Remarkable’. This series of episodes will share fascinating facts about sleep that will blow your mind! In the premier episode, Matt focuses on something truly (bloody) remarkable: half-brain sleep, or unihemispheric sleep. Unihemispheric sleep is the phenomenon of when one hemisphere of the brain is awake, while the other sleeps. Matt goes on to discuss how the two sides of the bra...

Matt returns with Part 2 of his series on sleep and weight gain. This time around, he teaches us how a lack of sleep not only makes you eat more food, but changes what types of food you want to eat, and eat to excess.First, Matt describes how underslept individuals that are limited to 4-5 hours of sleep for several nights will experience a 33% increase in the desire to eat obesogenic, sugary treats. In addition, they will suffer a 30% increase in craving for heavy-hitting carbohydrates, like ...

Matt kicks off a two-part series all about sleep, eating, and weight gain. He starts by introducing two appetite-regulating hormones: leptin and ghrelin. Matt explains how leptin sends a signal of fullness, to your brain. When leptin levels are high, your appetite is reduced, and you feel satisfied by the food you eat. Ghrelin does the exact opposite. It revs up your hunger, so when your ghrelin levels are high, you don’t feel satisfied by the food you ate, so you want to eat more.Matt t...

In the previous episode, Matt described the role of temperature in helping us fall asleep. In this episode, Matt teaches us all about the role of temperature in helping us stay asleep across the night, and then more effectively wake up the following morning.First, Matt takes us back to the body temperature suit experiments that were able to warm or cool different parts of the body. Matt explains that, using this same method, when you continue to cool the body throughout the first and middle p...

In today's episode, Matt reveals how 1) your own temperature and, even more precisely, 2) the temperature of different parts of you, as well as 3) the temperature of your bedroom, can change how well or how poorly you sleep at night.Matt describes the basic physiology of how your brain and body needed to drop their core temperature by about 1 degree Celsius, or about 2 to 3 degrees Fahrenheit, for a person to fall and stay asleep across the night. This is the reason why we will always find it...

In today's episode, Matt takes us on a deep dive into melatonin. He covers four main topics: 1) what is melatonin? 2) how does melatonin work? 3) what does melatonin do, and *not* do, for sleep? 4) how can we think about melatonin supplementation?First, Matt describes that melatonin is a naturally occurring hormone released by the brain. He gleefully notes that melatonin is often called, “the vampire hormone” as it comes out at night. In doing so, it signals that it is nighttime, which in tur...

In this week’s episode, Matt continues his discussion of sleep and caffeine. Here, we learn about the paradox of coffee, one in which coffee provides health benefits, despite its negative impact on sleep. Before addressing that, however, Matt speaks about one last sleep consequence of caffeine: regardless of your sensitivity to caffeine, it can still disrupt the quantity and electric quality of your deep non-REM sleep. This can lead to a cycle of caffeine dependency 1) you drink more coffee t...

In today's episode, Matt unpacks the world of coffee, and caffeine in the first of a two-part series on caffeine. Matt describes the numerous health benefits associated with coffee, the fact that Matt has even changed his tune a little and advocates a morning cup for some. Matt may not have anything to do with caffeine itself, with more details on that in part 2. In part 1, Matt then takes a deep dive into the different ways in which caffeine negatively impacts your sleep, some of which you m...

On last week’s episode, we learned about the three main ways alcohol can harm our sleep: 1) alcohol results in sedation rather than naturalistic sleep, 2) alcohol causes sleep fragmentation, and 3) alcohol impairs REM sleep. Today, Matt dives into each of these negative impacts, explaining exactly how and why alcohol disrupts our sleep in these specific ways.First, alcohol is a class of chemicals called “the sedatives,” and sedation is not natural sleep. Healthy sleep is a very active, h...

Although some people may believe that a drink or two in the evening will help them sleep better, today’s episode shows us that alcohol harms our sleep in several different ways. In the first of two episodes on sleep and alcohol, Matt talks about alcohol as a chemical, and the main ways it negatively affects our sleep.Alcohol has a sedative effect that switches off brain cell firing as we sleep. Alcohol also fragments our sleep, making it less restorative, and blocks REM sleep, which is critic...

As the great Roman poet, Ovid, once said, “There is more refreshment and stimulation in a nap, even of the briefest, than all the alcohol ever distilled.” But are naps always a good thing? Are we even designed to nap? And if you do nap, when should you do it, and for how long? Today Matt explores the benefits and pitfalls of napping, how napping may fall in line with our pre-programmed sleep patterns as humans (a natural drop in alertness between 1 and 4pm each day), and what it means if...

In the final episode of our three-part series about chronotypes, Matt examines the question of whether your chronotype is truly fixed, or if you can change an evening type to a morning type (though you will hear that Matt’s preference is for society to change, not the individual). Matt reviews a fascinating study by an Australian-lead research team that tried to turn night owls into morning larks. Participants had to follow a series of strict rules over the course of a three-week s...

In the second episode of our three-part series on chronotypes, Matt speaks about what happens when you do not sleep in harmony with your natural chronotype. Unlike morning larks, night owls simply cannot fall asleep easily early at night, which leads to the first and most obvious consequence of not sleeping in line with your chronotype—you don’t sleep as much.Matt explains that morning types sleep over 7-hours per night on average, while evening types can only manage 6.6-hours of sleep ...

Episode 04: Chronotype: Part 1SummaryAre you a morning type? Or are you an evening type? Perhaps you are neither of the two? Today’s episode is the first in a three-part series all about your chronotype, or your body’s natural biological preference to be awake and be asleep at a certain time. Matt begins by explaining exactly what your chronotype is, then breaks down the three main “flavors” of chronotype (morning lark, night owl, or somewhere in-between). In addition, and listed in the ...

#03 Circadian RhythmsContinuing on from last week’s episode about sleep pressure, today, Matt Walker dives into the second half of the sleep-wake story, circadian rhythm. Matt explains that your circadian rhythm, or your 24-hour internal clock, begins drumming out its loud activating beat just before you wake in the morning and gets louder throughout the day, peaking in the early afternoon and hitting its lowest point in the middle of your sleep phase overnight. Matt describes how c...

Episode 02: Sleep PressureWelcome back to the Matt Walker podcast. Today’s episode looks at the story of sleep pressure - how it works, how you can try to block it or fool it, and why you feel so good after a night of full, peaceful sleep. Matt explains that from the moment you wake up, a chemical called adenosine begins to build up in your body. The longer you’re awake, the more adenosine will build up and the sleepier you will feel. This is called sleep pressure. Once adenosine c...

Episode 01: HighlightsHuman sleep has been separated into two main types: Non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleepNREM sleep is further divided into four stages, with each stage increasing in their depth of sleepREM sleep is named this way because of the bizarre, horizontal, shuttling eye movements that occur underneath your eyelids during this stage of sleepREM sleep is the principal stage in which we dream, although it can occur in the other stages as wel...

The Matt Walker Podcast is all about sleep, the brain, and the body · Matt is Professor of Neuroscience at the University of California, Berkeley · He is the author of the book, Why We Sleep, and has given a few TED talks · Matt is an awkward British nerd who adores science and the communication of science to the public.