This is an AI translation of the Japanese report. Quotes from Japanese sources are translated, too.
We formed hypotheses from a problem Grok bot found on X (Oct 30), "I get into bed, but my thoughts won't stop and I can't fall asleep," and from the planning agent's plan to "book bedtime worries into a 15-minute 'worry time' at lunch tomorrow," and tested them against national surveys, the national sleep guide, research and the pages of similar apps. This is the groundwork for prototype 2026-10-30-d.
In short: Many adults can't fall asleep (about 3 in 10 people of working age don't get enough rest from their sleep), and the national sleep guide itself says that worrying in bed and using a phone make it harder to fall asleep. There is research showing that people who wrote down tomorrow's tasks before bed fell asleep faster, and that throwing away the paper you wrote your thoughts on makes you less swayed by them, so both the original proposal (send worries off as paper airplanes) and the plan (book them for lunch tomorrow) have backing. However, a 2025 study found that putting worries off to a set time reduced time spent worrying, but did not confirm that it helped people fall asleep. What could set this apart is answering "Already booked" when the same worry comes back, which we did not find in similar apps. It clashes with the government's advice not to bring phones into the bedroom, so it matters that the tool finishes in a few tens of seconds with the screen going dark, and that it makes no treatment claims.
1.Hypothesis validation
5Hypotheses
2Validated
3Partly / with conditions
0Invalidated
Hypothesis
Result
Evidence
Many adults get into bed and can't fall asleep, or don't get enough rest from their sleep
Validated
National survey: The "share of people who get enough rest from sleep" was 78.3% in 2019. Among people aged 20 to 59 it was 70.4%, so about 3 in 10 people of working age don't get enough rest from their sleep (Ministry of Health, Labour and Welfare, materials for Health Japan 21 (third term), 2024-03-11)
Getting worse: The share of people not getting enough rest rose from 18.4% in 2009 to 21.7% in 2018, and the government rated it "D: getting worse." In 2018, people in their 40s were at 31.4% (same materials)
Falling asleep: Yakuji Nippo reports that 59.0% of 500 working people in their 20s to 60s said they had at least one night in the past week when they had trouble falling asleep (2026-10-06, a survey by a drug company)
Worrying in bed and using a phone make it even harder to fall asleep
Validated
National guide: "Not bringing smartphones or tablets into the bedroom, and sleeping in as dark a room as possible, leads to good sleep" (Sleep Guide for Health Promotion 2023, February 2024). It also says phones put more light into your eyes than computers do
Vicious circle: The same guide describes a vicious circle in which anxiety about not sleeping grows, "time spent in bed unable to sleep, brooding, increases," and things get worse
Research model: In one model of insomnia, excessive worry creates mental and physical arousal that gets in the way of falling asleep (Harvey, 2002). Checking the clock again and again before sleep is also suspected of fueling worry (Tang et al., 2007; the paper itself says this has not been confirmed yet)
Writing worries down, or throwing them away, makes your head feel lighter (the core of the original proposal, "send them off as paper airplanes")
Validated with conditions
Writing them down: News reports say people who spent 5 minutes before bed writing "things I need to do" fell asleep faster than people who wrote "things I've done" (Baylor University in the US, 57 people, January 2018). The results come from university students with no sleep problems
Writing solutions: People who wrote solutions to their worries in the early evening had lower mental arousal before bed than people who only wrote their worries down (Carney & Waters, 2006, 33 university students with insomnia)
Throwing them away: People who threw away the paper with their thoughts written on it were not swayed by those thoughts in their judgments. Moving them to the trash on a computer gave similar results, but only imagining throwing them away did not work (Briñol et al., 2012; announced by Ohio State University)
Conditions: All of these studies are small and mostly involve young students. The researchers themselves say that throwing a thought away does not really make it disappear
Booking a worry for "a set time at lunch tomorrow" lets you let go of it tonight and fall asleep more easily (the core of the plan "Save It for Lunch")
Partly validated
Worry goes down: In a controlled trial of putting worries off to a set time (worry postponement), the group that added "if ..., then I will ..." plans spent about 15 minutes less per day worrying than the group that only postponed (McCarrick et al., Psychology & Health, published 2025-12-05, 186 people, 14-day diary)
Sleep not confirmed: In the same trial, the postponement groups did not improve significantly on any sleep measure, including falling asleep, compared with the control group (paper abstract)
How it's used: One suggested way to use worry time is "usually 30 minutes in the early evening" (FAQ of WorryTree, an app for recording worries). The plan to book it at lunch is close to this way of using it
How to read this: The tool can create the experience of your mind accepting "I don't have to think about this tonight," but it cannot claim that "you'll be able to sleep" (inference)
Answering "Already booked" when the same worry comes back is something today's tools don't do, and it makes the prototype stand out
Partly validated
Booking tools exist: There is an app that stores up worries and reminds you at a set time (ReachOut WorryTime), and an app where you set a time and place to sort your worries (Contain Your Brain). In Japanese, there is an app where AI helps sort out your worries (Awarefy) and a diary where you write short entries (Relief)
No tool that spots repeats: In the store pages and descriptions of the 6 apps we looked at, we found no feature that recognizes the same worry and answers "already booked" (inference; we did not look at every app)
Whether it lands is unconfirmed: That posts about "can't sleep" get many reactions on X is Grok's description, and we have not checked it
2.Timing of the story (when, and how far)
2002A paper sets out a model of insomnia in which "too much worry creates arousal that gets in the way of falling asleep" (Harvey)
Nov 2012An experiment is announced showing that throwing away written-down thoughts makes you less swayed by them (Briñol et al.)
Jan 2018An experiment finding that writing "things I need to do" before bed helped people fall asleep faster is reported (Baylor University in the US)
Feb 2024The national "Sleep Guide for Health Promotion 2023" comes out. It recommends not bringing phones into the bedroom
Mar 2024Targets for Health Japan 21 (third term) are set out: raise the share of people who get enough rest from sleep to 80% by fiscal 2032 (78.3% in 2019)
Dec 2025A controlled trial of worry postponement: time spent worrying went down, but sleep did not improve (McCarrick et al.)
May 2026News reports say the insomnia treatment app "Medcle" will be covered by public health insurance from June 1. The article says it is the first in Japan for insomnia
Oct 2026A drug company's survey is reported: 59.0% of working people had a night with trouble falling asleep in the past week
Timing verdict: This is a lasting problem that does not depend on the season or on trends. This year, insurance coverage for a treatment app (June) and an autumn survey have put "falling asleep" back in the news. If you post about it, the angle "not 'stop thinking,' not 'throw it away,' but 'book it for lunch tomorrow'" fits. It also seems to suit times when worries tend to pile up, like the end of the year or the days after a long holiday (inference).
3.What the problem really looks like
WhoAbout 3 in 10 people of working age (20 to 59) say they don't get enough rest from their sleep (2019). In the 2018 survey, people in their 40s were the highest age group, at 31.4%. The worries themselves differ from person to person (work, money, health, relationships), but the feeling of them going round at night is shared.
WhenAfter getting into bed. The national guide describes a vicious circle in which thoughts go round and anxiety about not sleeping pushes sleep even further away. It also says that once you start looking things up on your phone, the light from the screen suppresses the hormone that helps you fall asleep.
Why it happensResearchers explain that unfinished tasks and worries stay in your head. The idea is that writing them down lets you put them outside your head. Checking the clock again and again before bed is also suspected of fueling worry (a researchers' hypothesis).
4.Tools and technology today
Tool or technology
What it can do
What it can't do, and cautions
Insomnia treatment app (a medical device, Medcle)
Prescribed by a doctor, it delivers cognitive behavioral therapy (treatment that reshapes sleep habits and ways of thinking; CBT-I) over 9 weeks. The article says it is covered by public health insurance from June 1, 2026, at a reimbursement price of ¥24,100
Needs a prescription. Not a tool for casual use on a single night
Writing-down and self-care apps (Awarefy, Relief)
AI helps sort out your worries and vague unease (Awarefy); you record short entries and look back at them (Relief). Both are in Japanese and free with in-app purchases (as shown in the store)
Diary-style, used day and night. We saw no way to move a worry to a time tomorrow
Worry booking apps (ReachOut WorryTime, Contain Your Brain)
Store up worries and get a reminder at a set time. Set a time and place and sort worries into solvable / unsolvable / solved
In English. Many are aimed at young people. They don't recognize the same worry
Technology to tell whether two worries are the same
In a real version, an AI that turns how close two sentences are in meaning into a number could spot "different words, same worry" (inference). In the prototype, as the plan says, a sample check based on overlapping words decides
Wrong matches happen. It needs an escape route, "Something else," to fix them
Keeping it on the device
If bookings are kept in the browser's storage, they can be shown the next day without sending them anywhere (inference)
Not visible on other devices. It also needs a way to erase them
5.Competitors, and the gaps
Name
Who it's for
Price
What it can do
What's missing
ReachOut WorryTime
Young people in Australia (12 and up)
Free
Stores up worries and reminds you at a set time. You can also set how long the time lasts
In English. On the day we checked, the official page redirected to a list of apps and the store page showed an error, so we couldn't confirm it is still available
Contain Your Brain
People who worry a lot (13 and up)
Free
Set a time and place for worrying, enter worries by voice or text, and sort them into solvable / unsolvable / solved
In English. Only 7 ratings, so small. Doesn't recognize the same worry
WorryTree
People who worry a lot
Not checked
Record and sort out worries, and get reminders for things to do later. Some people use it to practice worry time (FAQ)
Not built for use before bed. It doesn't show worries stopping at a booked time
Awarefy
Adults in Japan
Free, in-app purchases
AI helps sort out worries and vague unease. Cognitive behavioral therapy and mindfulness (store description)
Not built to finish in a few tens of seconds before bed (inference). We saw no way to move worries to tomorrow
Relief (Meditation Diary)
Adults in Japan
Free, in-app purchases
Record your thoughts in short entries and write them out while looking back
No booking and no way to move things to tomorrow (as far as the store screenshots show)
Medcle
People with insomnia disorder (prescribed by a doctor)
Covered by public health insurance (article)
Treats insomnia with cognitive behavioral therapy
Needs a prescription. Not a casual tool for one night
The gaps (what the prototype aims for)
"Book it for lunch tomorrow" in just a few tens of seconds before bed. Today's booking apps are mostly used to move worries that come up during the day to a slot in the early evening
Answering "Already booked 12:35" when the same worry comes back. None of the competitors we looked at did this
The screen gets darker with each entry and closes at the end. This fits the government's advice not to look at a phone in bed for long
In Japanese, covering the everyday worries of adults (work, money, health, relationships)
6.Rules and things to watch
Rule
What it says
What to watch for in this tool
Rules on software as a medical device (the Pharmaceuticals and Medical Devices Act; "Guidelines on Whether Software Qualifies as a Medical Device," partially revised March 31, 2023)
Software used to diagnose, treat or prevent disease can count as a medical device. This is judged by its intended use and level of risk, and by how it is labeled and advertised. The government and the PMDA (Pharmaceuticals and Medical Devices Agency) have consultation desks
Don't claim it "cures insomnia" or "helps you sleep." Keep it to "a note that leaves your worries with tomorrow." Check with an expert whether it qualifies
Sleep Guide for Health Promotion 2023 (Ministry of Health, Labour and Welfare, February 2024)
Recommends not bringing phones into the bedroom and sleeping in as dark a room as possible
This tool is used on a phone, so it clashes with that advice. Build it to finish in a few tens of seconds, darken the screen and close at the end. In a real version, also consider advice to "use it before you get into bed" (inference)
The same guide's section "About sleep disorders"
If symptoms continue even after following the guide, it may be a sleep disorder. If one is suspected, see a medical institution promptly
Put a line like "If you can't sleep for days on end, see a doctor" in the description or in a corner of the screen
How the content of worries is handled
It becomes content people don't want others to see: work, money, health, relationships
A real version needs to never send it off the device and to make it easy to erase right away (inference; check the handling of personal information with an expert)
7.What we put in the prototype
What goes in: Short one-line thoughts typed on a phone in bed (15 to 20 characters in Japanese). For example: "How should I reply to my boss?", "Still haven't seen my checkup results", "Can I cover the bills at month end?", "Left my friend on read". One each for work, money, health and relationships, so they fit anyone's worries. Also prepare the same worry in other words (e.g. "Haven't replied to my boss yet").
What comes out: Tomorrow as a day strip (a timeline), with the lunchtime "15-minute worry time" slots lined up with times. Each slot shows the time, length and the one-line worry, like "12:35–12:40 Reply to my boss". We looked at our reference collection (not public): store screenshots of a planner app where the day's plans line up in a vertical strip with times and lengths, and screens of a worry app that puts small tags (solvable / unsolvable, and so on) on worries. We don't borrow the bright light-blue or white screens of Japanese writing-down apps (no bright screens before bed).
Features (up to 3): (1) Type one line, and the words that were going round overhead stop in tomorrow's slot at "12:35 for 5 min," and the screen gets one step darker. (2) Type the same worry in other words, and no slot is added: you get an "Already booked 12:35" tag with the matching booking next to it (if it's a different worry, "Something else" puts it in a new slot). (3) When 3 slots are full or you press "That's it for tonight," it shows how the 15 minutes are split and the screen closes dark (as the plan says, once 3 slots are full it re-splits within the 15 minutes).
What to leave out, and promises: Don't write "helps you sleep," "cures insomnia" or "makes worries go away" (because of the medical device rules, and because research has not confirmed that postponing worry helps people fall asleep). Don't keep showing the current time in large type (researchers suspect that checking the clock again and again fuels worry; if you show it, keep it small). No bright white screens, sounds or notifications. No AI advice on, or analysis of, the content (it only moves it to tomorrow). Don't send the content of worries off the device. In the description or a corner of the screen: "If you can't sleep for days on end, see a doctor." Research found people fell asleep faster before bed when they wrote "things I need to do" rather than "things I've done," so it helps to mix input examples in forms like "Check ..." and "Reply to ..." into the samples (optional).
8.What we couldn’t verify
The reaction counts on X (such as "155 likes, 18 replies") are Grok's description, and we have not checked them (we did not open the original post)
We couldn't find the national share of "people who get enough rest from sleep" for 2020 onward (the text uses the 2019 figure)
The details of the drug company's survey (500 working people), such as its questions and method (we could only read the start of the article)
We read about the 2018 experiment on writing "things I need to do" before bed in news reports. We have not read the paper itself or its exact numbers
We only read the abstract of the 2025 controlled trial of worry postponement. We have not seen its figures for falling asleep
Whether ReachOut WorryTime is still available (on the day we checked, the official page redirected to a list and the store page showed an error)
Whether there really is no app that answers "already booked" for the same worry (we only looked at 6 apps)
We found no research on how a tool used on a phone in bed for just a few tens of seconds affects falling asleep
We have not judged whether this tool counts as a medical device (it depends on labeling and advertising; check with an expert)
Medcle's insurance coverage date and price are the article's claims (we have not seen the government notice)
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