The Snooze Button

Could the lighting in your home or workplace be interfering with your sleep?

Chronobiologist Dr. Marijke Gordijn joins Neil Hedley to explore how light influences our biological clocks, why blue light isn't necessarily the enemy, and how changing our everyday lighting habits could improve our sleep.

Gordijn is the founder and director of Chrono@Work, a guest researcher at the University of Groningen, and a co-founder of the Good Light Group.

In this episode, we explore:

• The biological clock: What circadian rhythms actually are, and how our bodies keep track of time.
• The 500-lux problem: Why ordinary indoor lighting may be insufficient during the day.
• Blue light: Why we need it during the day but should limit it as bedtime approaches.
• Shift work: The challenges of working while our biological clocks are telling us to sleep.
• Power naps: Why even a short period of rest may improve alertness.
• Night owls and creativity: Whether our individual biological rhythms influence when we perform our best.
• Melatonin: Why timing and dosage matter, and why it isn't necessarily a solution to poor sleep quality.
• Practical changes: How daylight exposure, evening lighting and screen habits can help support healthy circadian rhythms.

Dr. Marijke Gordijn

Chronobiologist, Founder and Director of Chrono@Work, Guest Researcher at the University of Groningen, and Co-founder of the Good Light Group.

Chrono@Work — Dr. Gordijn's research organization

Good Light Group — Practical guidance on healthy lighting

University of Groningen — Marijke Gordijn's research profile

2022 Scientific Consensus: Recommendations for Daytime, Evening and Nighttime Light Exposure

• Why Brian and his colleagues expected sleepy employees to “punch down” in the workplace
• The surprising result that conflict was strongest with higher-ranking people
• Why the U.S. Army provided an especially interesting environment for studying hierarchy
• What workplace conflict actually looked like in the research
• Neil’s highly scientific description of the problem as a failing “BS filter”
• Why self-control may help explain the connection between sleep and conflict
• How poor sleep can affect anger, risk-taking and rule-breaking as well as interpersonal conflict
• Why recognizing a bad night’s sleep may help you manage the following workday differently
• How chronotype and time of day can compound the effects of poor sleep
• Sleep, workplace injuries and the danger of simply blaming the employee
• Why organizations themselves can contribute to employees’ sleep problems
• The idea of sleep leadership
• Whether managers should be asking employees how they slept
• Why unpredictable work schedules can be particularly disruptive
• Shift work and the importance of regularity when regular daytime schedules aren’t possible
• Whether the same sleep-and-hierarchy dynamic might show up between parents and children
• What happens when both the employee and the boss are sleeping badly
• Whether poor-sleep conflict could cascade upward through an organization
• Why Brian wants to see the findings tested outside the military and in flatter organizations
• What employers can reasonably take away from this research — and what this single study cannot establish

Dr. Brian Gunia is Professor and Area Chair for Management & Organization at the Johns Hopkins Carey Business School.

His research examines negotiation, organizational behavior and sleep, with particular interest in the ways insufficient sleep can influence decision-making and behaviour in the workplace.

His work has explored topics including sleep and self-control, leadership, ethics, negotiation and interpersonal conflict.

Before entering academia, Brian worked as a management consultant. He earned his PhD in Management & Organization from Northwestern University.

Sleep and Strife: The Effects of Sleep on Conflict within Organizational Hierarchy

Brian Gunia, Paul Bliese and Amy Adler examined the relationship between sleep problems and interpersonal conflict inside organizational hierarchies. Their research found that sleep problems were most strongly associated with conflict involving people of higher rank — the opposite of what the researchers initially expected.

Brian Gunia — Johns Hopkins Carey Business School

Faculty profile, research interests and selected publications.

In this episode:

• Jesse Cook, Cathy Goldstein and Olivia Walch grade their own sleep
• Why the answer to “Do most people need granular sleep-stage data?” is no
• Clinical sleep definitions versus consumer wearable outputs
• Why an EEG headband has an advantage over a motion-only tracker — but still is not a polysomnogram
• Sleep sensitivity, wake specificity and the trap hidden inside a 90% accuracy claim
• Why REM and deep-sleep staging are harder than basic sleep/wake detection
• What quiet wakefulness does to wrist-based algorithms
• Why actionability can matter more than precision
• Orthosomnia and the risks of sleep perfectionism
• Why one bad nightly score should not become a crisis
• How tracker validation changes across populations and sleep disorders
• Why proprietary algorithm updates can age a validation study overnight
• The case for access to raw sensor data and shared validation datasets
• What the World Sleep Society and National Sleep Foundation now recommend for consumer sleep technology
• Why healthy sleep includes more than duration
• Sleep regularity, rhythmicity, continuity, timing and daytime functioning
• Why a low consumer deep-sleep score cannot be translated directly into dementia risk
• What glymphatic research actually says about sleep stages
• Neil’s Dreem 2 data and which numbers catch the panel’s attention
• Temperature, awakenings and using wearable trends to test practical hypotheses
• Why mainstream trackers may be enough for most behavioral goals
• The importance of comfort, adherence and battery life
• FTC and FDA oversight of consumer health and wellness claims
• What seven-to-nine-hour recommendations actually mean
• Why trying too hard to sleep can become part of the problem

Jesse Cook, PhD, is a sleep researcher and clinical psychologist at the University of Wisconsin–Madison. His work has examined sleep and mental health, hypersomnolence, athletes and the performance of wearable sleep technology. Cook previously joined The Snooze Button for a full episode devoted to the question of who validates the trackers themselves.

Dr. Cathy Goldstein is a Clinical Professor of Neurology at the University of Michigan and a sleep physician whose work includes consumer and clinical sleep technology, circadian rhythm disorders and the use of wearable data. Her research has included efforts to improve and openly evaluate algorithms used to characterize sleep from wearable sensors.

Olivia Walch, PhD, is a mathematician and circadian scientist whose research focuses on biological rhythms, sleep timing and mathematical models of the human circadian system. She is affiliated with the University of Michigan Center for Sleep Science and is CEO of Arcascope, which develops circadian-health technology.

Archive update, 2026: At the time of this conversation, Walch’s book was still on the way. Sleep Groove: Why Your Body's Clock Is So Messed Up and What To Do About It was published January 28, 2025 by Andrews McMeel. The book uses comics and circadian science to explain why sleep timing goes wrong and what people can realistically do about it.

• Jesse Cook — University of Wisconsin–Madison
• Cathy Goldstein — University of Michigan Medical School
• University of Michigan Center for Sleep Science faculty
• Olivia Walch and Arcascope
• Sleep Groove: Why Your Body's Clock Is So Messed Up and What To Do About It
• Selecting a sleep tracker: EEG-based, multisensor and actigraphy-only devices
• 2025 validation of six commercial wrist-worn sleep trackers
• 2026 rapid review: real-world use of consumer sleep devices
• World Sleep Society recommendations for wearable consumer health trackers that monitor sleep
• National Sleep Foundation position statement on consumer sleep technology
• Screening for orthosomnia and sleep-related preoccupation
• U.S. survey of consumer sleep technology use, trust and sleep-related worry
• Which sleep health characteristics predict all-cause mortality in older men?
• Sleep regularity as a predictor of mortality risk
• American Heart Association statement on multidimensional sleep health
• 2023 mouse study: sleep-cycle-dependent vascular dynamics and predicted CSF flow
• Norepinephrine-mediated slow vasomotion and glymphatic clearance during sleep
• FTC Health Products Compliance Guidance
• FDA General Wellness: Policy for Low Risk Devices — 2026 guidance
• AASM/SRS recommended amount of sleep for a healthy adult
• National Sleep Foundation sleep-duration recommendations

In this episode:

• Why Jade Wu had just woken from a nap before the interview
• Why she thinks of naps as snacks
• What happens when trying to make sleep happen becomes the problem
• Why Wu wrote Hello Sleep
• The access problem surrounding Cognitive Behavioral Therapy for Insomnia
• Who CBT-I is actually for — and what it does not treat
• Why an overnight sleep study is not routinely necessary for uncomplicated insomnia
• Neil's periodic limb movements and the case for treating comorbid sleep problems together
• What happened when a sleep psychologist became a severely sleep-deprived new parent
• Sleep disruption, postpartum depression and the danger of single-cause explanations
• Why sleep can be foundational without being the explanation for everything
• How sleep optimization and sleep trackers can create pressure
• Why melatonin is a timekeeping hormone rather than a sedative
• The label-accuracy problem in commercial melatonin products
• When melatonin may have legitimate circadian uses
• Why chronotype can collide with school and work schedules
• How social media and streaming services compete with sleep
• Why daytime light changes the brain's sensitivity to evening light
• What the evidence does — and does not — say about screens and blue-light blocking
• Mindfulness without turning mindfulness into another performance task

Dr. Jade Wu, PhD, DBSM, is a board-certified sleep psychologist, researcher and author of Hello Sleep: The Science and Art of Overcoming Insomnia Without Medications. Duke University currently lists her as an Associate in Research whose work focuses on treating sleep disorders in people with chronic illness. Her own site describes her broader work in behavioral sleep medicine, public education and her company Thrive; it also lists her as a Clinical Assistant Professor at SUNY Upstate Medical University and says she will join Cornell University's Psychology Department faculty in Fall 2026.

Wu earned her undergraduate degree at Cornell, her PhD at Boston University, and completed medical psychology residency and clinical fellowship training at Duke University School of Medicine.

• Hello Sleep: The Science and Art of Overcoming Insomnia Without Medications — Jade Wu
• Jade Wu — Duke Department of Neurology
• Dr. Jade Wu
• AASM guideline: behavioral and psychological treatments for chronic insomnia
• 2025 systematic review: CBT for adult insomnia in routine clinical care
• AASM practice parameters: evaluation of chronic insomnia and use of polysomnography
• 2017 study: melatonin content variability and serotonin in commercial supplements
• 2023 study: melatonin and CBD quantities in U.S. melatonin gummies
• Health Canada: melatonin as a natural health product
• AASM pharmacologic guideline: melatonin and chronic insomnia
• The human circadian system adapts to prior photic history
• 2024 National Sleep Foundation consensus statement on screens and sleep
• 2025 systematic review and meta-analysis of blue-light blocking glasses and objective sleep
• The Many Challenges of Insomnia — Dr. Jade Wu
• Sex & Sleep: Was It Good For You?

After she had her baby, Dr. Jade Wu from Duke University School of Medicine basically went through every sleep issue in the known universe. We talk about how the script gets flipped when the doctor becomes the patient.

In this episode:

• Why major changes in sleep science often take years to become visible
• How scientific knowledge becomes more nuanced instead of simply replacing “wrong” answers with “right” ones
• Why no single sleep stage should automatically be treated as the only stage that matters
• REM sleep, deep sleep and the brain's overnight fluid dynamics
• What p-values are trying to tell us about uncertainty
• Why replication and converging evidence matter
• The problem with treating scientific revision as scientific failure
• What “normal sleepers” means in device-validation research
• Why sleep trackers may mistake motionless wakefulness for sleep
• Why disagreement between a wearable, a sleep lab and your memory does not have a simple answer
• How to think about consumer sleep technology as a measurement tool rather than a truth machine
• The evidence for later middle- and high-school start times
• Teen driving safety and later school schedules
• Why sleep and circadian researchers favor permanent standard time
• The conflict between circadian biology and our preference for brighter evenings
• Where the idea of a 90-minute sleep cycle comes from
• Why 90 minutes is an approximation, not a sleep-planning rule
• How the human appetite for “secret knowledge” turns useful observations into rigid sleep hacks

Dr. Michael Grandner is a licensed clinical psychologist and behavioral sleep medicine specialist at the University of Arizona. He directs the Sleep and Health Research Program and the Behavioral Sleep Medicine Clinic at Banner – University Medical Center Tucson, with appointments across psychiatry, medicine, psychology and related programs. His research spans insufficient sleep, sleep health, cardiometabolic and neurocognitive outcomes, social and environmental influences on sleep, health disparities and behavioral interventions.

On the day this episode was released — June 3, 2024 — Grandner was receiving the Associated Professional Sleep Societies' Diversity, Equity and Inclusion Leadership Award, recognizing contributions to broadening access and representation and reducing sleep-health disparities. The award has since been renamed the APSS Inclusive Leadership Award.

• Michael Grandner — University of Arizona College of Medicine
• APSS Inclusive Leadership Award and past recipients
• Dementia and Sleep: It's Not Just Deep Sleep That Counts with Dr. Laura Bojarskaitė
• Bojarskaitė et al.: Sleep cycle-dependent vascular dynamics and predicted cerebrospinal-fluid transport
• 2025 meta-analysis: consumer wrist-worn sleep trackers compared with polysomnography
• 2026: Consumer sleep technologies — what we know and what comes next
• AASM position statement on later middle- and high-school start times
• Adolescent sleep, school start times and teen motor-vehicle crashes
• AASM: Permanent standard time is the optimal choice for health and safety
• Review of human sleep architecture and 90–110 minute NREM/REM cycles

Dr. Michael Grandner from the University of Arizona returns to the show with a look at one of the problems facing the scientific community.

Everything from sleep to Covid to REM sleep vs Deep sleep, the 'truthiness' of science claims - all of it is on our exam table.

• Why Lawrence Gowan says he often sleeps better on a moving tour bus than almost anywhere else
• How sleep differs among members of Styx on the road
• Why trust in the tour-bus driver matters to Gowan's ability to switch off
• How touring fitness changes when musicians move through their 40s, 50s and beyond
• Gowan's transition from hockey to weights, yoga, walking and cycling
• Why performing more than 100 shows a year is physical work in its own right
• How Gowan thinks about protecting and developing his singing voice with age
• The deliberately classic progressive-rock sound of Crash of the Crown
• Queen, Genesis, Yes, Jethro Tull, The Who, vintage keyboards and analog gear
• Why Styx still isn't in the Rock & Roll Hall of Fame
• Gowan's practical sleep habits: schedule, less phone time and writing down late-night worries
• The autobiographical memory exercise he uses when awake at four in the morning
• Why musicians can obsess for hours over a mistake the audience never noticed
• Dr. Mark Boulos on restless legs syndrome, periodic limb movements and augmentation
• Why suddenly worsening RLS should trigger a review of iron, sleep, medications and other conditions
• Neil's experience of worsening movement symptoms after a mental-health medication change
• Why vortioxetine/Trintellix should not be described as an SNRI
• What current evidence does — and does not — say about antidepressants and RLS
• How current RLS treatment guidance has shifted away from routine dopamine agonists such as pramipexole
• Why bupropion as an antidepressant option is different from bupropion as an RLS treatment
• The danger of crowdsourced medication advice when nobody knows the full clinical picture

Lawrence Gowan is a Canadian singer, songwriter and keyboardist whose solo career produced hits including A Criminal Mind, Strange Animal and Moonlight Desires. He joined Styx in 1999 and remains the band's keyboardist and one of its principal vocalists and songwriters. He contributed to Styx's 2025 album Circling From Above, the band's 18th studio album.

Dr. Mark Boulos is an Associate Professor of Neurology at the University of Toronto and staff neurologist at Sunnybrook Health Sciences Centre. He serves as Medical Lead for the Sunnybrook Sleep Laboratory and Program Director for the University of Toronto Sleep Neurology Fellowship. His clinical and research interests include sleep-related movement disorders, sleep and stroke, home sleep monitoring, sleep data and novel approaches to diagnosing and treating sleep disorders.

Styx — current band and Circling From Above

The band's current lineup, including Lawrence Gowan, and its 2025 studio album.

Styx official band page

Styx official music page

Crash of the Crown — Styx

The 2021 album discussed extensively in Neil's conversation with Gowan.

Styx discography

Rock & Roll Hall of Fame — 2026

The official nominee and inductee lists; Styx does not appear on either.

2026 performer nominees

2026 inductees

Dr. Mark Boulos — University of Toronto

Current academic and clinical profile, including his roles with the Sunnybrook Sleep Laboratory and Sleep Neurology Fellowship.

University of Toronto profile

AASM clinical practice guideline for RLS and PLMD

The current guideline on iron assessment, exacerbating factors and treatment, including the shift away from standard dopamine-agonist use because of augmentation risk.

Read the guideline on PubMed

TRINTELLIX / vortioxetine prescribing information

Current drug labeling describing vortioxetine's indication and serotonergic mechanism.

DailyMed prescribing information

Antidepressants, RLS and periodic limb movements — systematic review

A review finding that antidepressant-associated RLS worsening is possible but appears uncommon overall, with meaningful differences among medications.

Read the systematic review

Vortioxetine and RLS — conflicting case literature

A 2019 case report linked vortioxetine to RLS; later reports described improvement in some patients. These small reports are useful mainly because they show why a single simple rule is not justified.

2019 case report

2023 case series

Bupropion and RLS

A small randomized trial found that bupropion did not exacerbate RLS and may have improved symptoms short term. Current AASM guidance nevertheless recommends against using bupropion as a treatment for RLS itself — a different question from choosing an antidepressant in someone who also has RLS.

Read the randomized trial

One is an actual rock star - Lawrence Gowan from Styx talks about health, fitness and sleeping on the tour bus for rock stars who are, like fine wine, getting better with age. (He also weighs in on Styx not being members yet of the Rock & Roll Hall of Fame.)

The other is a rock star in the sleep world - Dr. Mark Boulos from Sunnybrook Health Sciences Centre in Toronto is Neil's sleep specialist, and offers important information that could completely change the life of someone you care about if sleep issues come along with mental health concerns as well.

• Why sex and sleep are surprisingly difficult to study in a laboratory
• How at-home sleep technology may make naturalistic research more practical
• The difference between association, mechanism and an actual sleep intervention
• Why trying too hard can interfere with both sleep and sexual function
• Performance anxiety and the danger of turning intimacy into another sleep obligation
• Why "good sex" does not automatically mean orgasm
• Jade Wu on embodied attention, mindfulness and getting out of the insomnia thought loop
• Wendy Troxel on relationship safety, vigilance and sleep as a social behavior
• Michael Grandner on conditioned arousal and why the bed should not become "the dentist chair"
• Cheryl Carroll on "bed dread" and making the bedroom feel safe rather than threatening
• How fertility-related performance pressure can affect both sex and sleep
• Why sleeping apart does not automatically mean relationship trouble
• Possible psychological and physiological pathways linking intimacy with sleep
• What later research found about partnered sex, orgasm, masturbation and sleep
• The 2025 pilot study that measured sexual activity and sleep with at-home polysomnography
• What newer research says about insomnia, sexual satisfaction and sexual dysfunction
• A 2026 correction to the episode's statement about sleep deprivation and testosterone
• Why the panel ultimately resists turning sex into a standardized sleep prescription

Dr. Michael Grandner is a licensed clinical psychologist certified in behavioral sleep medicine and a professor at the University of Arizona. He directs the Sleep and Health Research Program and the Behavioral Sleep Medicine Clinic. His research examines sleep health, insufficient sleep, sleep disparities and the relationship between sleep and cardiometabolic and daytime functioning.

University of Arizona profile

Dr. Jade Wu is a board-certified sleep psychologist, researcher and author of Hello Sleep: The Science and Art of Overcoming Insomnia Without Medications. Her current research at Duke University School of Medicine focuses on treating sleep disorders in people with chronic illness.

Duke University profile

Dr. Wendy Troxel is a senior behavioral and social scientist at RAND, a licensed clinical psychologist specializing in behavioral sleep medicine, and an adjunct professor at the University of Pittsburgh and University of Utah. She is the author of Sharing the Covers: Every Couple's Guide to Better Sleep and is internationally recognized for research on sleep in couples and relationships.

RAND profile

Cheryl Carroll, DNP, CNM, PMHNP-BC, PMHCNS-BC, CST, is a women's-health and mental-health clinician and an AASECT-certified sex therapist with more than thirty years of experience. She now owns StrongTower Counseling and Education in Durham, North Carolina, where she works with individuals, couples and families.

StrongTower Counseling and Education

Congresswoman Stacey Plaskett and Her Surprising Sleep Routine

The earlier Snooze Button episode that started the sleep-and-sex question.

Listen / read the episode

Please Don't Make Us Call It a Sleep Divorce

Neil's earlier conversation with Wendy Troxel about couples who sleep separately and what that choice does — and does not — say about a relationship.

Listen / read the episode

Hello Sleep — Jade Wu

Wu's book on insomnia, behavioral sleep medicine and building a healthier relationship with sleep.

Duke University on Hello Sleep

Sharing the Covers — Wendy Troxel

Troxel's book on sleep in couples and the intersection of sleep, relationships and health.

Wendy Troxel at RAND

Sex and Sleep: Perceptions of Sex as a Sleep Promoting Behavior in the General Adult Population

The 2019 survey study showing that many adults perceive sexual activity involving orgasm as helpful for subsequent sleep.

Read the study

The influence of sexual activity on sleep: A diary study

The 2023 study that followed sexual activity and subjective sleep across fourteen days.

Read the study

Sleep on it: A pilot study exploring the impact of sexual activity on sleep outcomes in cohabiting couples

The 2025 pilot study using portable polysomnography in participants' homes — a practical answer to one of the methodological problems debated in this episode.

Read the study

Relationship of insomnia to sexual function and sexual satisfaction: Findings from the Sleep and Sex Survey II

A 2023 study of 1,266 adults examining insomnia severity, sexual function and sexual satisfaction.

Read the study

Effect of partial and total sleep deprivation on serum testosterone in healthy males

The systematic review and meta-analysis used for the archive correction to the episode's testosterone discussion.