The late-night "just one more episode" habit can harm your brain—Specialists warn about the risks and countermeasures of "staying up late to watch"

Table of Contents

1. Introduction: Why Has "Late-Night Viewing" Accelerated?

2. Dr. Daniel Amen's Warning: The Crime of Stealing "Brain Washing Time" Fox News

3. What is the Glymphatic System? Latest Insights on the Brain's "Drainage Pipe" OHSU NewsBrainFacts

4. Blue Light and Melatonin Suppression: How Light Disrupts the Sleep Hormone Harvard HealthChronobiology in Medicine

5. Multilayered Effects on Judgment, Memory, and Emotional Control: Clinical and Neuroimaging Evidence

6. Japan's Streaming Environment and "FOMO" Culture: Insights from Domestic Surveys

7. New Risks in the Multi-Screen Era: Smartphones and "Doomscrolling" WIRED

8. Self-Care to Protect Your Brain: 8 Practices You Can Start Today

9. Recommendations for Society: The Role of Companies, Schools, and Media

10. Conclusion: "Going to Bed 30 Minutes Earlier" Can Save Your Future Brain

1. Introduction: Why Has "Late-Night Viewing" Accelerated?

1-1 Competition Among Streaming Platforms and the "Binge-Watching" Culture

The "all episodes at once" model of Netflix and Amazon Prime Video, and near real-time episode releases like Peacock's 'Love Island,' stimulate viewers' psychology to watch even late at night to avoid spoilers. According to the Ministry of Internal Affairs and Communications' 2024 Communication Usage Trend Survey, the average weekly viewing time for people in their 20s reached a record high of 47.2 hours. The trend of securing viewing time at the expense of sleep is becoming more pronounced.

1-2 "Social Jet Lag" and Economic Incentives

Advertisers and platforms are pushing notifications and "late-night marathon releases" assuming late-night viewing, widening the weekday-weekend gap in life rhythms. This creates "social jet lag," leading to a chronic state of jet lag.

2. Dr. Daniel Amen's Warning: The Crime of Stealing "Brain Washing Time"

Dr. Amen, renowned for brain imaging diagnostics, told Fox News, "Sleep is the only time the brain is physically cleansed. Even losing 30 minutes can lead to poor decision-making the next day."Fox News

"If you want to improve tomorrow's memory, go to bed 30 minutes earlier tonight."

He points out that a sleep-deprived brain is like "unwashed dishes," with waste products remaining, and the accumulation of β-amyloid and tau proteins increases the long-term risk of dementia.

3. What is the Glymphatic System? Latest Insights on the Brain's "Drainage Pipe"

Proposed in 2012, the glymphatic system is a network where cerebrospinal fluid (CSF) washes through the brain parenchyma, removing waste products. A study by Oregon Health & Science University in October 2024 reported that "waste removal efficiency improves by 80-90% during deep non-REM sleep."OHSU NewsBrainFacts

3-1 Waste Accumulation and Alzheimer's Disease

β-amyloid accumulation inhibits synaptic communication and accelerates neurodegeneration. Chronic sleep deprivation shortens the operating time of this system and can induce early onset of tau pathology.

4. Blue Light and Melatonin Suppression: How Light Disrupts the Sleep Hormone

A review by the Harvard School of Public Health reported that "blue light suppresses melatonin twice as much as red light."Harvard Health
A meta-analysis also found that nighttime smartphone, TV, and LED lighting stimulate retinal melanopsin cells, delaying the secretion of sleep hormones, resulting in an average delay of 14-30 minutes in sleep onset. Furthermore, in younger individuals, there is a noted decrease in learning efficiency and an increased risk of mood disorders.Chronobiology in Medicine

5. Multilayered Effects on Judgment, Memory, and Emotional Control

5-1 Functional Decline of the Prefrontal Cortex

fMRI studies show a significant decrease in blood flow to the prefrontal cortex during sleep deprivation, with error rates in risk judgment tasks increasing by 1.6 times. Late-night stock trading or studying for exams after staying up late often leads to a "losing battle."

5-2 Inhibition of Memory Consolidation in the Hippocampus

Pruning of spines and synaptic strengthening that occur during non-REM sleep are insufficient, leading to a 15% decrease in episodic memory recall the next day.

5-3 Excessive Reaction of the Amygdala

In experiments using emotionally stimulating images, the sleep-deprived group showed a 60% higher amygdala response, with a significant increase in the stress hormone cortisol secretion.

6. Japan's Streaming Environment and "FOMO" Culture: Insights from Domestic Surveys

In a survey conducted by the NHK Broadcasting Culture Research Institute in March 2025, 48.7% of people in their 20s responded that they "watch late at night to keep up with the next day's topics." Avoiding spoilers on social media is considered the main reason for staying up late.
Additionally, the simultaneous streaming of reality shows in Japan has increased 2.6 times over the past three years, and the average bedtime has shifted from 23:17 to 23:46.

7. New Risks in the Multi-Screen Era: Smartphones and "Doomscrolling"

Recently, not just watching TV but also following the timeline of X (formerly Twitter) on smartphones while watching programs has become common, known as "interactive consumption." This multitasking places the brain's default mode network in an overactive state, leading to chronic stress. A 2024 review also pointed out that "content dependency is a major cause of sleep delay rather than blue light."WIRED

8. Self-Care to Protect Your Brain: 8 Practices You Can Start Today

1. Screen Off 90 Minutes Before Bedtime: Turn off smartphones, PCs, and TVs, and use indirect lighting

2. Automatic Blue Light Filter: Enable at the OS level after sunset and reduce OLED brightness

3. Time Budgeting Method: Set an "end alarm" before viewing and force-stop after one episode

4. FOMO Countermeasures: Turn off SNS notifications and set "mute words" to join conversations even after watching the next morning

5. Fixed Bedtime Rituals: Prioritize the parasympathetic nervous system with reading, breathing exercises, and stretching

6. Digital Detox in the Bedroom: Physically remove devices from the bedside

7. Optimizing Light Environment: Use warm-colored LEDs below 2700K at night and reset with high-intensity light upon waking

8. Minimize Weekend Recovery Sleep: "Catching up on sleep" disrupts circadian rhythms. Aim for +15 minutes on weekdays

9. Recommendations for Society: The Role of Companies, Schools, and Media

• Streaming Companies: Refrain from push notifications after midnight and introduce "sleep mode"

• Educational Institutions: Set deadlines for online assignments by 9 PM to ensure students' sleep time

• Government and Local Authorities: Revise and promote "sleep guidelines" based on the Health Promotion Act

• Companies: Shift meeting times to the morning and introduce employee sleep education programs

10. Conclusion: "Going to Bed 30 Minutes Earlier" Can Save Your Future Brain

Late-night viewing, as a short-term entertainment cost, steals the brain's cleaning time, affecting decision-making, memory, and emotions. As Dr. Amen calls it "a test of self-love,"the top priority should be sleep. By turning off screens 30 minutes earlier starting today, you can simultaneously achieve waste removal, memory integration, and emotional stability in the brain. Your future brain depends on the choices you make tonight.

📚List of Reference Articles (External Links, Chronological Order)

1. 2013-10-23
   　🔗 Does Sleep 'Brainwash' Us? – BrainFacts.org
   　→ Introduction to early research on waste removal in the brain during sleep (glymphatic system).

2. 2014-10-01
   　🔗 Blue Light Has a Dark Side – Harvard Health Publishing
   　→ Effects of blue light on melatonin and precautions for device use before bedtime.

3. 2021-12-16
   　🔗 What Is Doomscrolling? – Cleveland Clinic
   　→ Impact of smartphone "doomscrolling" on psychological state and sleep.

4. 2023-10