Note that Circadian Sleep Disorders Network is not affiliated with any pharmaceutical, medical device, or other company.
Circadian Rhythm Sleep Disorders (CRSDs or CRDs) are neurological disorders in which the sleep-wake cycle is out of sync with the day-night cycle. These include in particular Delayed Sleep Phase Disorder and Non-24-Hour Sleep-Wake Disorder. Also included are Advanced Sleep Phase Disorder, Irregular Sleep Wake Disorder, and Shift Work Disorder, which are defined here.
Delayed Sleep Phase Disorder (DSPD), also called Delayed Sleep Phase Syndrome (DSPS), is characterized by an inability to fall asleep until very late at night, with the resulting need to sleep late in the morning or into the afternoon. Questions? See our DSPS Q&A.
Advanced Sleep Phase Disorder (ASPD), also called Advanced Sleep Phase Syndrome (ASPS), is the opposite. It is characterized by falling asleep very early in the evening, and waking up in the wee hours of early morning, unable to sleep further.
Non-24-Hour Sleep-Wake Disorder (Non-24), also called Free-Running Disorder (FRD), is a condition in which a person's day length is significantly longer than 24 hours, so that sleep times get later each day, cycling around the clock in a matter of days or weeks. Questions? See our Non-24 Q&A.
Some people use the term reverse sleep, referring to the fact that sometimes people with DSPD and Non-24 end up sleeping during daylight and being awake at night.
We are asking our members and followers to give our brochure, and/or our Q&A booklets, to their sleep doctors and their general doctors on their next visits. It is vital to all of us suffering from circadian disorders that more doctors and their support staff understand these disorders and how disruptive they can be. The more doctors who know about us, the more patients we can reach, inform, and support. And the larger our membership, the more credible our voice on behalf of all people with circadian sleep disorders.
You can print out the brochure on U.S. letter paper (8½x11) or on A4 paper (non--U.S.). Booklets can be printed for DSPS or for Non-24 (the same file can be printed on either U.S. or A4 paper). Alternatively you can email us at to request a printed copy of any or all these documents (please specify which, and how many you really need). Be sure to include your name and full postal address. We will send these at no charge to you.
Apr 7, 2022
CSD-N Board Member Alexandra Wharton was officially welcomed to the NIH (U.S. National Institutes of Health) Sleep Disorders Research Advisory Board (SDRAB). She represents the circadian sleep disorders patient community. Alex is the social media liaison for CSD-N, and is also a chapter leader for Start School Later.
The SDRAB receives updates on the progress of sleep and circadian research activities across NIH, and the activities of Federal stakeholders and professional societies. The board is responsible for periodic updates to the NIH Sleep Disorders Research Plan, and advises the NIH on next steps.
March 25, 2022
LumenAstra and the Microwave Lab at the University of Colorado Boulder (Prof. Zoya Popovic, right) are developing a small, wearable sensor for measuring internal body temperature. They recognize the need for easier continuous non-invasive core body temperature monitoring.
The team contacted CSD-N President Peter Mansbach to learn more about diagnosing circadian rhythm sleep disorders. This sensor could in principle provide a simpler way of definitively diagnosing DSPD and especially Non-24, using a procedure both less invasive and less demanding than measuring DLMO (Dim Light Melatonin Onset) under "constant routine" conditions (dim light, no exercise, etc).
March 13, 2022
The old Indian said, "Only the government would believe you could cut a foot off the top of a blanket, sew it to the bottom, and have a longer blanket."
Jan 25, 2022
CSD-N board member Alexandra Wharton was invited to speak at the Congressional briefing on Jan 25 for the (U.S.) NIH Sleep Disorders Research Plan. She gave a wonderful introduction to DSPD for the attendees. The briefing was carried live on Zoom, and was open to the public. You can view her seven minute presentation here. The entire hour-long briefing is available here.
The Sleep Disorders Research Plan was developed by the National Center for Sleep Disorders Research (NCSDR), a center within the U.S. National Institues of Health. The Plan was developed with the help of the Sleep Disorders Research Advisory Board. Thanks to Susan Plawsky, who represented the circadian sleep disorders patient community on that board during the Plan's development.
Dec 13, 2021
The National Center on Sleep Disorders Research, part of the U.S. National Institutes of Health (NIH), announces the release of the 2021 NIH Sleep Research Plan. This new research plan presents a comprehensive approach to addressing the critical research needs and opportunities in sleep and circadian biology.
The plan was developed with input from the public, scientific communities, the Sleep Disorders Research Advisory Board (SDRAB), the NIH Sleep Research Coordinating Committee, NIH leadership, and partners across the Federal government, with the goal of advancing sleep and circadian research that improves medicine, public health, and the safety of the nation.
Many thanks to Susan Plawsky for ably representing Circadian Sleep Disorders Network on the SDRAB through four years of painstaking work, despite all the bureaucratic wrangling over wording and the compromises required.
Tune in to NIH's LinkedIn Live Event on Thursday, December 16, 2021 beginning at Noon ET to ask questions about the new plan.Archived News 2021
This is a free mailing list support group for people with DSPS and Non-24 to share their experiences. It's a good place for people just discovering these disorders to hear how others deal with them, as well as for long-time participants to get support and to provide support to others. There are often discussions of evolving treatment, useful to all. For further information, and to sign up, go to www.circadiandisorders.org/list.
Note that membership in Circadian Sleep Disorders Network and membership on this email list are completely separate.
Circadian Sleep Disorders Network is affiliated with this email list, and our volunteers assist the list administrator with some chores. CSD-N was formed by participants on this list, and many of our members post regularly. But we have no control over what appears or who can join, and list membership is completely separate from membership in CSD-N.
Once you've signed up for the list, you post by sending an email to Everyone on the mailing list receives that post as an email, and you receive everyone else's posts as emails. If you don't like to get separate emails, you can opt to receive in digest form, typically one email a day containing all the day's posts. You make that selection after signing up by logging in (using the password you created when signing up for the email list) at www.circadiandisorders.org/list.
There are some rules:
The rules that the list software enforces are
An additional rule is PLEASE do not just reply to a message with a subject line containing "Niteowl Digest, Vol xxx, Issue xxx". That is obviously not informative and if you aren't careful you may include the whole list of messages in the Digest, making your message too large for the list.
Digest or not, it is a good idea to trim whatever you are replying to leaving just enough for people to know what you are replying to.
Once you've signed up for the list, you can also browse previous posts in the archive at
There is also a mirror of the archive on Yahoo at https://groups.yahoo.com/neo/groups/nite-owl/info. This is useful when the primary archives are not working, as sometimes happens. Login to your Yahoo account, or create one (free) - link is at the top right on that page. Then you have to join the Yahoo copy of the list - this is separate from signing up for the list itself - there is a button on the Yahoo page to do this.
To unsubscribe from the Niteowl email list go to
and follow the directions at the bottom of the page. You will need to know your list password.
If you do not know your list password, send email to
with PASSWORD in the subject line. This email must come from the same email address that you subscribed from (which is the one your incoming Niteowl list emails go to). Your password will be sent to you at that address.
If that doesn't work, you can unsubscribe by sending email to
with UNSUBSCRIBE in the subject line. This email must come from the same email address that you subscribed from (which is the one you your incoming Niteowl list emails go to). If you do this, you will get an email back asking you to confirm. You must follow the instructions and confirm, or you will not be unsubscribed.
For more (or more current) help on list commands, send email to
with HELP in the subject line.
Our brochure is geared to the general public, to introduce DSPD (DSPS) and Non-24 to people experiencing symptoms of these disorders, and to their families.
Please distribute it to anyone who may be interested.
Print on lightly colored paper for some color, if you like. We used ivory.
|Brochure - web display||
Print on US letter size paper, PDF
Print on A4 size paper, PDF
The web display version shows the brochure panels in easy-to-read order. The print versions are meant to be printed out on both sides of a sheet of paper, then folded in thirds, creating a brochure. (In the print version, the panels will appear out of order on-screen.)
We have posted documents describing DSPD (DSPS) and Non-24, in an easy to read Question-and-Answer format. These are designed to give to family members, friends, employers, and school personnel, to help them understand these disorders. Feel free to print and distribute these. There are two different (but similar) versions, one for DSPD and the other for Non-24:
|DSPD Q&A - web||printer||booklet*|
|Non-24 Q&A - web||printer||booklet*|
The web formats display nicely in your browser.
The printer versions are formatted by your browser for printing a multi-page document.
The booklet forms are pre-formatted PDF files that you can print on two sides of a single sheet of paper, which then folds in half into a booklet.
* When printing the booklet, be sure to flip on the short edge (select this option if you have a double-sided printer).
|Spanish:||DSPS Preguntas y Respuestas - web||printer|
|No-24 Preguntas y Respuestas - web||printer|
|German:||DSPS F&A - web||printer|
|Non-24 F&A - web||printer|
We also have a one page Basic Fact Sheet that introduces DSPD and Non-24 to people who don't know about them. It's a quick and easy read, just the basics.
Former board member and artist Lily Style has created an infographic describing Circadian Rhythm Sleep Disorders. View it in your browser at www.circadiansleepdisorders.org/docs/CRSDGraphic.php. Feel free to repost the graphic to help raise awareness.
You can print it directly from your browser (we suggest making the browser window full screen - the image will resize). We are also posting JPG images in various proportions for printing directly on different sizes of paper:
We are offering merchandise (mugs, T-shirts, tote bags, bumper stickers, and a messenger bag) with our name and logo through CafePress,
www.cafepress.com/circadiansleepdisordersnetwork. (Note: if you just search CafePress you will find this merchandise, but at a higher price!)
Circadian Sleep Disorders Network is a Coalition Partner of Start School Later. We understand only too well the difficulties many teens have with early school start time, and we support the move to start school later.
The first time you go to smile.amazon.com you will be asked to confirm Circadian Sleep Disorders Network as your charity. Amazon will remember your selection. But you do have to go to smile.amazon.com instead of simply amazon.com, for each purchase, if you want 0.5% of that purchase to go to CSD-N. Note that you pay the same amount either way - through Smile the 0.5% goes to us, otherwise it goes to Amazon.
We have already received several contribution checks from Amazon! Please select Circadian Sleep Disorders Network as your charity. smile.amazon.com
Also available on the the Amazon Shopping app on your phone. How it works there:
Amazon and the Amazon logo and AmazonSmile and the AmazonSmile logo are trademarks of Amazon.com, Inc. or its affiliates.
This is a list of refences added to our Info page since the last newsletter. The newsletter lists references added since the previous newsletter. These are generally available to members only.
This web site is intended to provide generic information about Circadian Rhythm Sleep Disorders, and
is not intended to replace discussions with a healthcare provider.
You should not use the information on this website for diagnosing or treating a medical or health condition.
All decisions regarding patient care should be made with your healthcare provider.
Office: 4619 Woodfield Rd, Bethesda, MD 20814
Phone: By appointment only, please.
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