Dr. Jim Phelps of PsychEducation.org keeps track of just about every kind of therapy, proven and emerging, medicinal and not, for bipolar disorders. Most of us are now famiiar with the use of light therapy for winter depression, or Seasonal Affective Disorder …
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Ack, sloppy click, I tried to vote ’5′ and missed. Can some admin fix this? This is an excellent page.
My wife and I had relamped our whole house with compact fluorescents over the years (I bought my first ones, from Phillips, literally decades ago, when they cost $40 apiece, they’re still working).
When I came across the Brainerd et al. study on the photoreceptor that controls melatonin, it was an eye opener. We’d both had insomnia in recent years, and tended to read in bed under a little CFL til, oh, midnight, one am … then I’d wake at 4 or 5 am.
So — I got some amber LED lights (did you know they’re certified by the Florida fish and game people? Here’s their wonderful page, any of these would be great evening lights indoors:
http://myfwc.com/seaturtle/WildlifeLighting/index.htm
Amber is good for use near sea turtle hatcheries, so the baby turtles head toward the rising moon over the ocean instead of toward the beach houses?).
I also found low-blue-light CFLs (GE “Post Light Bug Light” compact fluorescents are very low blue, not “no blue” so there’s some color vision remaining).
Check CFL spectra here:
http://ledmuseum.home.att.net/spectra7.htm
This is the GE buglight we find very good:
http://ledmuseum.candlepower.us/seventh/cflbl1.gif
No insomnia that night. None since. We turn down the bright/blue lights at about 8pm. By 10pm, I’m yawning and can’t keep my eyes open.
Haven’t fallen asleep like this since I was a kid.
Oh, and it’s really helped the winter depression I’ve fought for decades, getting _enough_ sleep like this. March and April used to be the worst months, while everyone else was cheering up and I’d still be sunk in gloom.
Not this year.
NOTE, there are a lot of states (California) and countries (Australia) proposing to get rid of incandescent lights and push compact fluorescents.
Be afraid.
And if you live near the SF Bay Bridge, you’ve noticed the huge, bright, blue-led billboard next to the Oakland end. It’s stunningly bright blue light. Imagine every billboard glaring that bright — brighter than life, bright as the blue daytime sky.
Scary.
P.S. — for covering existing lights, you can use the yellow polycarbonate drinking water bottles from Walgreen’s, etc (don’t let them overheat, though).
For covering lights AND computer screens (and flashlights) you can get Rosco theatrical gel filters at any good photo or theater lighting supplier, for about $7 for a 20×24″ piece. Deal!
This is “Daffodil”
http://www.rosco.com/images/filters/roscolux/310.gif
That blocks most light below about 470nm (though you’d want to add their ultraviolet blocking filter as well, for any fluorescent light)
http://www.rosco.com/
Hank, you are brilliant! Thanks so much for the leads. Gels are an especially great idea.
Credit the idea of using Rosco gels to Murray Waldman.
The Rosco Chroma Green (to _pass_ not _block_ the range that affects melatonin) is mentioned in this patent as an example:
Therapeutic light method – US Patent 5447527
… In case a broad spectrum bulb is used, a ROSCOLUX™ type Chroma Green #75 filter can …
http://www.patentstorm.us/patents/5447527-description.html
That’s using green light (whether from a green source or using that kind of filter) to _provide_ rather than _block_ part of the range that affects the melatonin receptor, for treating winter depression.
Check his site — http://www.sunnexbiotech.com — for a lot of good science info; Sunnex now sells a green light for SAD that I use and can recommend.
Note at the LEDMuseum website I mentioned in the earlier post, have a look at all the fluorescent (and white LED) spectra Craig has posted there. Both fluorescent and white LED emit a _lot_ of blue light. Fluorescents are mercury vapor emitters with phosphors; “white” LEDs are blue LEDs with phosphors, to convert some of the primary emission to longer wavelengths in the visible range.
Got a light you wonder about? Box it up and mail it to Craig at the LEDMuseum page; he checked the ones I sent him, the spectrum I linked above for the GE ‘post light bug light’ is one of those.
NOTE the LEDMuseum is a one-person website, it’s world famous among those of us who like that sort of thing. Craig’s a great guy, with a quirky sense of humor. So if you want his help, send him a sample of the light you’re curious about (and a contribution, if you will).
Quite a few manufacturers do this; so do a lot of us individuals who are curious. That reminds me, I’ve got a couple more possible “low blue” emitters to mail him to see what he makes of them.
——–> Last thought —-> There’s debate whether NO or LOW blue light is the criterion; I’m no scientist, just an avid reader. See also the cataract replacement lens science (one search merely as an example):
http://www.google.com/search?q=cataract+IOL+%22blue+light%22+mental+alertness
There’s debate whether IOLs for cararacts should block blue light.
Looks to me it appears that it’s not wise to block it with an intraocular lens …. and, hmmm, maybe natural yellowing of lenses cuts down on how well our brains work??? Could that be one reason older people’s sleep patterns fall apart, and supplemental bright light’s helpful? just speculating there).
Whew …..
I am currently legally disabled due to nearly life-long recurring clinical depression which has tended (as is often the case) to get worse with each major recurrence, and I finally became functionally debilitated several years ago [I am 52], despite some pharmaceutical relief. (My body reacts atypically to most anti-deps, and only Nardil, an old MAOI rarely prescribed today, has proven to be reliably useful.)
I have also had atypical (and frequently shifting) sleep patterns all of my life. I wouldn’t call it “insomnia”–but my system seems completely divorced from the “normal” diurnal cycle. Even as a child, I seemed to be built more for a 36-hour day than a 24-hour one. As I’ve gotten older, my sleep-cycles have gotten even more erratic and unpredictable.
What’s more, it has often been remarked upon–by my psychological caseworker and others–that I tend to have a much better emotional affect on the days when I’ve been up all night, than on the days when I’ve gotten the “normal” amount of sleep.
As far as I know, I am unique in this. Does anyone know if similar cases have been documented and studied? I would love to know as much as possible about such cases, if so.
Thank you.
I tried yesterday; if this is a duplicate, please discard it, but I don’t see yesterday’s reply here.
Sam — search Google Scholar — you’ll find good information about how losing sleep lifts mood. Try:
+”sleep deprivation” +antidepressant
For sleep cycles and patterns try
http://www.cet.org
They’ve got an online questionnaire that you may find helpful, and a lot of good information.
I hope you’ve read the articles linked in the original article above about light and dark therapies. In particular, the lack of help from the newer antidepressants and some research about low mood make sense — Dr. Phelps has a _lot_ of good information as is pointed out above (and info about how to talk to a doctor who doesn’t know about it, as well).
Note in the first response above, the link given is to the spectrum from an 11-watt GE “Post Light bug light” compact fluorescent (rated for 6,000 hours).
New info — here below is the spectrum from the 14-watt GE compact fluorescent ‘bug light’ (rated for 10,000 hours).
This spectrum also from the LEDMuseum site. There’s nobody like him for this kind of good info.
I’m glad to see this size is also quite low in the blue band.
It’s a noticeably brighter light source, a bit closer to yellow-green than to yellow-orange I’d say. Both are quite tolerable for evening light.
We’re using a mix of both kinds, along with the amber LED bulbs.
Note these CFLs both take two or three minutes to come up to full brightness. Don’t switch them on and off frequently, that reduces the lifetime.
http://ledmuseum.candlepower.us/eighth/gecflbl.gif
Aside — these are pricey at retail; I found them recently for about $7/apiece:
Amazon.com, searching there for
+CFL +bug +GE
Hunt around patiently if you’re looking for them, the pricier stuff shows up more prominently.
Couple more filter notes.
Rosco generally:
http://www.rosco.com/us/filters/roscolux.asp#colors
That’s the brand I’ve got handy at a nearby theater/photo store; another one often available is a company named GAM. Google ….
Another good blue-blocking Rosco filter, #312 “Canary” — cutoff sharp at 500nm so it blocks a bit more of the blue-green.
(Note at short wavelengths most all color filters pass the UV emission present in ordinary fluorescent light; see spectra):
http://www.rosco.com/images/filters/roscolux/312.gif
This is Rosco’s UV filter (I use layered with my color filters) — optically completely clear:
Roscolux #3114: UV Filter (Transmission = 100%).
For winter blues, the “Chroma Green” — mentioned in the patent noted earlier — has a new number now, #389: http://www.rosco.com/images/filters/roscolux/389.gif
This DESPERATELY needs to be more widely talked about, and tried. I followed Hank’s directions- and for the first time in 15 years, I am able to sleep without medication. Do you understand how astonishing that is?
What happened 15 years ago? I installed a compact fluorescent bulb as my bed/reading lamp. It’s unplugged now; currently using amber LEDs, which are plenty bright for reading.
My exact situation- for 15 years, I’d take diphenhydramine at bedtime- and have to read for 2-3 HOURS before I could drop off to sleep. Without the diphenhydramine- I’d wake up at 1 or 2; and be totally unable to get back to sleep. Devastating.
Literally- I am now UNABLE to keep my eyes open more than 15 minutes after getting into bed- with the amber LED’s. No matter how exciting the book..
Hank. It’s changed my life.
Looking back, please credit the article by Janet Raloff from Science News Online as a source for information; it’s by far the best single summary, with thorough footnotes — model science writing. I just reread it and was reminded how much of the useful information I know came from here. It’s in two parts; the second part is what I found very informative:
http://www.sciencenews.org/articles/20060527/bob9.asp
Science News Online
Week of May 27, 2006; Vol. 169, No. 21
Light Impacts
Hue and timing determine whether rays are beneficial or detrimental
Janet Raloff
This is part two of a two-part series
Done, and thank you again, Hank. If you come across anything more please let us know, it’s been a wonderful boon.
Shop around; Jim Phelps points to a source for yellow-filter glasses for $40; here’s a better price. These pass 65%; I used them before we changed our lights and put the Rosco yellow filters on my laptop screen; then I gave them a neighbor.
http://www.noir-medical.com/uv_yellow.htm#Percents
Search engines can find them on sale.
These look even better, haven’t tried them yet:
http://www.noir-medical.com/glareshield.htm
These folks
http://store.lsgc.com/Wildlife-Friendly-C14.aspx
have the best brightness-per-dollar amber LED lights I’ve found; shop around, watch out for really dim amber LED lights for too much money. Amber LEDs emit zero blue light, they can be quite bright and not interfere with sleep, in our experience. We’re using the older variety now, mixed with the low-blue “bug light” GE CFLs.
Their newer amber floodlight promises twice the brightness for the same ~6 watts (that’s progress in LEDs, which are changing very fast). Trying those next.
NOTE — most all current 110v LED lights, like almost all compact fluorescents, will fail (and may catch fire) if used on dimmers. Don’t do that!
Bottom line: the Rosco filter gels and yellow glasses are the inexpensive way to try this out.
Watch out for surprises; there are “daylight” incandescent bulbs that are very blue (neodymium is used in those).
Ordinary low-low-wattage incandescents don’t have a lot of blue emission, but egad, once you’ve compared a 6-watt night light incandescent to a 6-watt amber LED light (or even an 11-watt CFL “buglight”) you realize you can save the money on electricity that you spend changing your lighting.
The glasses are also super funky. Maybe it’ll start a trend?
Good to know that about dimmers! I’m moving into a new place that has a lot of dimmer switches. I’m a bit uncertain about how to filter those lights, since there are several chandeliers.
I’d just not use those lights after say 8pm; have your low/no-blue bulbs in table lamps, reading lamps.
If you use only the 20watt or 40 watt ‘candle flame shape’ low-wattage incandescents in the ‘candelabra/dimmer’ fixtures that’s probably what they’re meant for, the fake-candlelight look; once an incandescent is dimmed down it’s mostly red and infrared anyhow.
Old dimmers are very noisy electronically; if you have a computer/phone/DSL cable anywhere near them, expect static/garbage when you’re using them. The old dimmers are just rheostats (coils of resistor wire, wasting as heat anything below full brightness setting).
They are the candle flame-shaped bulbs, so that’s good, not too damaging. But I’ll use others after dark.
Those little ‘candelabra’ incandescents can be found with an amber tint, which would eliminate all the blue — more like candlelight.
Any ordinary incandescent won’t be very strong in the blue (except halogens); once they’re dimmed they’re cooler and redder yet.
http://ledmuseum.candlepower.us/seventh/60wincan.gif
Here’s our problem:
http://ledmuseum.candlepower.us/eighth/soyomon.gif
(add a layer of one of the Rosco gels that blocks light below 500nm )
http://ledmuseum.candlepower.us/fifth/mon1.gif
http://ledmuseum.candlepower.us/fifth/nik1.gif
Another bit suggesting “low blue” may be better than “no blue” to my way of reading it. Found here:
http://www.caa.govt.nz/medical/ME_Newsletters/Med_news_10_06.pdf
From the literature: Blue light and the blues
A presentation at the recent ASAM (Australasian
Society of Aerospace Medicine) annual scientific
meeting, in Launceston Tasmania
1, raised some
interesting possibilities in respect to blue light. The
presentation was given by Dr Dan Black, and
eminent Australian aviation ophthalmologist.
The main line of reasoning pursued the relationship
between blue light and depression, with some
collateral discussion concerning the colour-vision
effects of ‘natural’ intra-ocular lenses. The
reasoning went something like this:
- Our eyes contain non-image-forming photoreceptors
in the retinal ganglion cells and these receptors are
especially sensitive to short wavelength light;
- Blue light exposure influences (amongst other
things) the production of melatonin, alertness, the
growth of tumour cells, sleep architecture, and mood;
- The amount of blue light reaching these non-image-
forming photoreceptors will be reduced by:
Yellow-orange spectacle lenses (“blue-blockers”
or high-contrast lenses);
The yellowing of the lens with normal ageing;
Many intra-ocular lenses, which are tinted yellow
in an attempt to reduce the likelihood of macular
degeneration; Blue-blockade reduces the amount of melatonin
produced and, therefore, has the capability to
moderate circadian adaptations as well as mood;
- After cataract surgery patients may become
anomalous trichromats because of the yellow tint of
the IOLs that have been inserted … although this tint
may also closely resemble the colour-cast of their
aged lenses anyway (less cyanopsia with yellow-
tinted, or ‘natural’ IOLs);
- Cataract surgery, and the insertion of a blue-blocker
IOL, may also predispose to depressive illness.
Dr Black emphasised that although much of the
logic and reasoning is supported by good solid
research some remains somewhat conjectural …
including his postulating a link between SAD
(seasonal affective disorder) and blue light
exposure. All the same, the available information
does make for some interesting considerations.
References and abstracts available (5Mb PDF file)
and can be emailed to anyone who wishes.
1
Black, D. Cataract surgery implicated in depressive illness. The 2006
Annual Scientific Meeting of the Australasian Society of Aerospace
Medicine (A Flight of ideas: Mental Health in Aviation). Launceston
Country Club, Tasmania, Australia, 21 September 2006.
Oops, attribution omitted; for anyone who didn’t get the context, those images come from
http://www.ledmuseum.org (for the ‘front door’)
http://ledmuseum.candlepower.us/eighth/soyomon.gif
is a typical LCD computer display–lots! of blue.
The other two images linked above are typical compact fluorescents, also with lots of blue
(anything below about 500 nanometers)
I got some of these and they are quite good fitting over eyeglasses: http://www.noir-medical.com/glareshield.htm
As it gets to the equinox I have to start thinking about winter depression again; the dawn simulator’s in use (http://www.humboldt1.com/~zerdo).
This is the time of year — as the days get short and we don’t have blue skylight coming in the windows into the evening hours — where I’ll find out if blocking all the blue in our electric light makes winter depression worse, as I suspect it does.
This will be the first winter trying to control SAD _and_ keep sleeping well. Bright light and daylight and standard fluorescents in the morning and up til about 8pm, then switching to low- or no-blue.
Gonna be tricky, doing it mostly with clipon and Luxo-type lamps for the low-/no-blue bulbs so those go on when the standard brighter general illumination goes off. Fiddly, for now.
For for general evening lights (in the absence of evening sunlight coming in after 8pm as it has been!) I’ll use more of the Westinghouse compact fluorescent ‘bug lights’ to have more low-blue emission, into the evening. We’d been getting that from the lingering daylight while we used just the yellow/amber CFL or LED lights between 8 and 9pm, while the days were longer.
One big note for anyone following — we notice the biggest source of blue light in the evening is definitely the computer. If you read online before going to bed and find your thinking spinning along at daytime speed — try the Rosco filter gels or yellow eyeglasses starting at 8pm or so.
New research in, confirming some of the above.
http://cercor.oxfordjournals.org/cgi/content/abstract/17/12/2788?ct
“…Using functional magnetic resonance imaging, we show that, while participants perform an auditory working memory task, a short (18 min) daytime exposure to blue (470 nm) or green (550 nm) monochromatic light (3 x 1013 photons/cm2/s) differentially modulates regional brain responses. Blue light typically enhanced brain responses or at least prevented the decline otherwise observed following green light exposure in frontal and parietal cortices implicated in working memory, and in the thalamus involved in the modulation of cognition by arousal. Our results imply that monochromatic light can affect cognitive functions almost instantaneously and suggest that these effects are mediated by a melanopsin-based photoreceptor system.”
I think we’d call that “aqua” or “blue-green” light, which is within the band that seems to affect melatonin/sleep/arousal — but this is a much faster effect than a change in melatonin and seems to be an additive one (no idea what the background level of light was in this, all I have is the abstract). Could be there’s yet more going on.
Folks, got older relatives? Natural eye lenses get yellow with age and reduce blue light.
Thanks for keeping us informed, Hank.
Thanks for patiently allowing people to add to your topic!
I pointed to you from this thread a couple of times recently:
http://well.blogs.nytimes.com/2007/11/05/curing-insomnia-without-the-pills/
I noted this over at that NYT thread but it belongs here, this thread is the best collection of info I know of online.
New on light:
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0001247
Green Monochromatic Light Exposures in Humans: Prominent Role of Blue Light and the Brainstem
Abstract
Relatively long duration retinal light exposure elicits nonvisual responses in humans, including modulation of alertness and cognition. These responses are thought to be mediated in part by melanopsin-expressing retinal ganglion cells which are more sensitive to blue light than violet or green light…. …
Thanks for the update, much appreciated!
http://www.eurekalert.org/pub_releases/2007-12/cp-bhl121307.php
——excerpt—
“… this information may change how injuries to the eye are treated.
For example, surgeons might want to think twice about removing a damaged eye that still possesses functioning pRGCs, given the important physiological role that these cells play in maintaining normally timed sleep…. how light affects sleep, alertness, performance, and human health….”
I wondered if that might be the case – thanks for that link, Hank.
BTW, check out my relevant new tattoo.
http://scienceblogs.com/omnibrain/2007/12/multimedia_friday_new_tattoo.php
Wow. I am not brave enough to get tattooed with plain ink. Though I might go for phosphorescent ink or someday-nanotech conductive ink with a built in web browser and ham radio *grin*.
Long article in yesterday’s NYT about compact fluorescents, which made me think that a lot of the complaints (‘not warm’ and ‘not homelike’) may be people’s recognition of the blue light — perhaps we’re wired to recognize blue light as the market that we are outdoors and so at risk of predators?
If so none of the cheap fixes fiddling with the “color temperature” are going to solve that.
Earlier NYT article on compact fluorescents:
http://dotearth.blogs.nytimes.com/2007/12/07/experiences-with-next-generation-lighting/#comment-6873
Yesterday’s comparison of bulbs:
http://www.nytimes.com/2008/01/10/garden/10lighting.html?ref=garden (with pictures) or printable:
http://www.nytimes.com/2008/01/10/garden/10lighting.html?ref=garden&pagewanted=print
I accidentally stumbled on this article here and read all the posts… All I have to say is that whoever this Roberts guy is, he’s doing an outstanding job in providing information an this subject!
Thank you Hank, please keep it up. Btw I live in Europe.
http://www.blackwell-synergy.com/doi/abs/10.1111/j.1600-079X.2007.00473.x
MINI REVIEW
Kristen J. Navara, Randy J. Nelson (2007) The dark side of light at night: physiological, epidemiological, and ecological consequences
Journal of Pineal Research 43 (3) , 215–224 doi:10.1111/j.1600-079X.2007.00473.x
=====================
http://www.springerlink.com/content/w57m0451647x5444/
Biological Clocks and Shift Work: Circadian Dysregulation and Potential Long-term Effects
Journal Cancer Causes and Control
Issue Volume 17, Number 4 / May, 2006
Special Section on Cancer and Rhythm
DOI 10.1007/s10552-005-9015-4
============
Revisiting this thread because I’ve been sitting at bedside at a children’s hospital with my young niece during chemotherapy for leukemia, and noticed this:
– the staff’s trying hard not to wake up the kids at night, they’re using LED headlamps, camping-store gear.
But they’ve got the typical “white” LEDs that are very bright in the blue spectrum — this youngster’s mother spends the night and said when the staff comes in the LEDs wake her up clear across the room, let alone waking the kid in the bed they’re trying to help sleep.
They’re trying for something better than turning on the room fluorescents every few hours.
I’m taking in the references on amber lighting — a single one of the big bright amber “turtle lights” in a bedside lamp would be plenty of illumination to work around the bedside, if the hospital put them in.
Also trying to run down someone who can modify the “white” LED headlights by swapping in amber LEDs (this requires a slightly lower voltage supplied, it’s not a direct swap, it’ll need a resistor added to the circuits).
In other news, red LED light’s shown to reduce mouth sores –I’m going to get this youngster at least a very bright red LED flashlight before her next round of chemotherapy begins.
That’d be a good new topic, Sandra!
http://bloodjournal.hematologylibrary.org/cgi/crossref-forward-links/109/5/2250
Here’s a cite to a publication by Dr. Phelps (whose work our host Sandra introduces at the top of this article).
Note the “related article map” at the bottom of the linked page
http://www.find-health-articles.com/rec_pub_17637502-dark-therapy-bipolar-disorder-using-amber-lenses-blue-light-blockade.htm
Thanks Hank! I linked to Dr. Phelps’ article a few weeks back but I’m glad you shared the link with the related article map (and text). It led me to some research that fills in more gaps, which also led me to find more fun glasses than some of the clunky amber glasses I’d looked at: BluBlockers and BluBlocker Viper. Heh. An 80s product, retro fashion with new health implications.
http://www.blublocker.com/gallery/history.html
Blublocker seems to have changed their web page, the above link’s broken but you can find them through their main page
http://www.blublocker.com/
I wish they said what percentage of light those transmit; I think they’re “sun” glasses and so probably pretty opaque for indoor evening wear.
I’ve tried the yellow tinted glasses and it’s just easier to have a separate set of evening lights in amber and yellow — once we put the amber 25 or 40-watt incandescents in the refrigerator, that is. Those are easy to find in hardware stores. No more midnight glare.
A bit more on spectra — here’s a secondary source that appears to be a copy from Brainerd’s 2001 article
http://www.lighttherapycanada.biz/images/LB/ResEng/Brainardcurve2.gif
That’s the band you want to _avoid_ to be able to fall asleep (and the band you want to get to wake up and stay alert, of course — daylight blue skylight as filtered through green leaves, more or less. I have a “Go Outdoors” sign to remind me of that at home!).
The link goes to a winter depression/light therapy commercial site, here
http://www.lighttherapycanada.biz/bluelightresearch.htm
which appears to make a good case for using their product rather than standard bright white fluorescents.
There is also a green-phosphor fluorescent (sunnexbiotech.com), which I used for the first time this past for winter blues and worked fine for me.
Both of those seem safer than the old white lightboxes — they don’t emit in the shorter blue wavelengths, which are higher-energy photons.
How did I miss this til now?
http://www.patentstorm.us/patents/5402190-description.html
Biological cycle affecting goggles
US Patent Issued on March 28, 1995
This is a _much_ earlier description by the same Murray Waldman whose work I mentioned earlier, of the same range of light controlling wakefulness. This isn’t the _mechanism_ (the part of the eye controlling melatonin) but it’s the effect, clearly descdribed:
——-excerpt follows——-
… light wavelengths between about 480 and 530 nm. reaching the eyes at an inappropriate time with respect to the biological cycle, rather than all light wavelengths as had been previously thought, appear to be the wavelengths which cause the inappropriate resetting of the biological clock and allow the user to control, in conjunction with appropriately timed exposure to light capable of affecting the internal human clock, the timing of his normal functioning with normal wakefulness and alertness. Accordingly the present invention avoids resetting of the biological clock which would be caused by the presence of sunlight during intervals unexpected by the human body….”
It popped up when I searched this, thinking I’d find the later patent mentioned. Somehow I’d never seen this earlier one.
This well predates the Brainerd and other work. I wonder how he figured this out!
More research here for some science writer, some day, to follow up — I hope it interests someone to delve into how this all came up.
http://www.google.com/search?q=%2Bwaldman+%2Bpatent+%2Brosco
More:
“Polychromatic light was more effective at suppressing nocturnal melatonin than monochromatic blue light matched for melanopsin stimulation, implying that the melatonin suppression response is not solely driven by melanopsin. The findings suggest a stimulatory effect of the additional wavelengths of light present in the polychromatic light, which could be mediated via the stimulation of cone photopigments and/or melanopsin regeneration. The results of this study may be relevant to designing the spectral composition of polychromatic lights for use in the home and workplace, as well as in the treatment of circadian rhythm disorders.”
Chronobiol Int. 2007;24(6):1125-37.
Light-induced melatonin suppression in humans with polychromatic and monochromatic light.
Revell VL, Skene DJ.
http://www.ncbi.nlm.nih.gov/pubmed/18075803?dopt=Abstract
More:
http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=18082405
Curr Biol. 2007 December 18; 17(24): 2122–2128.
doi: 10.1016/j.cub.2007.11.034.
PMCID: PMC2151130
Copyright © 2007 Elsevier Ltd.
Short-Wavelength Light Sensitivity of Circadian, Pupillary, and Visual Awareness in Humans Lacking an Outer Retina
Last bit:
——excerpt——
Our data strengthen the conclusion that the clinical diagnosis of ”complete” blindness (i.e., visual and circadian) should assess the state of both the image-forming and the non-image-forming photoreceptive systems [1]. If blind individuals are found to be light sensitive, this knowledge will help ensure that they expose their eyes to sufficient daytime light to maintain normal circadian entrainment and sleep/wake rhythmicity. This evaluation is particularly critical prior to bilateral enucleation because, if light-responsive eyes are removed or individuals do not expose their eyes to a robust light-dark cycle, the patients may develop a debilitating circadian-rhythm sleep disorder [3, 14]. Patients with diseases of the inner retina that result in retinal ganglion cell death (e.g., glaucoma) are at particular risk and should be counseled about the effects of pRGC loss. Where complete blindness results, appropriately timed melatonin treatment may be warranted in order to establish entrained circadian rhythmicity [35, 36].
—–end——
Just one more — if you get the light bright enough, even red has some effect. This is rather bright.
http://www.ncbi.nlm.nih.gov/pubmed/16687299?dopt=Abstract
Hey Hank, thanks for posting all of this great additional information and links to the research. It’s very much appreciated!
http://selene-ny.org/downloads/environmentaleffects.ppt
(No cites in the paper, but interesting numbers, I’ll try to look them up)
Brightness:
Brainerd — exposure to 1/2 footcandle fully stops melatonin production
Blask — melatonin inhibits the growth of breast cancer cells in-vitro by 30-40%
Blask — tumors in lab rats grew 2 times as fast for those exposed to normal light during the day and 2/100 footcandle of light at night
…
Full moon = 1/100th footcandle
to as much as 2/100th f.c.
Scary, isn’t it? Here’s one for you:
http://www.pnas.org/cgi/content/abstract/105/12/4898
Light deprivation damages monoamine neurons and produces a depressive behavioral phenotype in rats, M. M. C. Gonzalez and G. Aston-Jones, PNAS
“These findings indicate that [enforced darkness] induces neural damage in monoamine brain systems and this damage is associated with a depressive behavioral phenotype.”
Great catch, Sandra.
Scary that too.
A good reminder there’s _much_ more going on:
http://scienceblogs.com/clock/2008/05/a_huge_new_circadian_pacemaker_1.php
Next to last paragraph here
http://adsabs.harvard.edu/full/2001JRASC..95..276P
quotes Dr. Brainerd on the intensity (0.5 to 1.7 footcandles of 509nm [blue-green] light, or 10 footcandles of white light]. This is from a 2001 Dark Sky Association meeting where he spoke.
Still hunting a better cite, in my copious spare time
How do footcandles translate to watts or colours etc. – what to buy?
Sandra, I’m no expert, I just read and point at things. Below something on what we buy, and below that something on what the terms mean.
I don’t have time to edit this into a short answer, so here’s the ramble:
I think the short answer is, avoid white light even as dim as a ‘nightlight’ bulb* not because the overall room illumination from that is so much, but because you’re apt to look straight at it from fairly close if you have one of them on.
We continue to really like these:
http://store.lsgc.com/R20-AMBER-FLOODLIGHT-MEDIUM-EDISON-BASE-P54.aspx
One in a clamp lamp pointed at the ceiling lights up a whole room well enough to get around at night, without interrupting feeling sleepy at all. If I’ve got to get up (bathroom, raccoon trying to get through the cat door, minor earthquake, wrong number phone call) I can click one of those on and see everything I need to without feeling like it’s hard to get back to sleep. By contrast, if I turn on a white fluorescent in the middle of the night — I’m going to have trouble getting back to sleep. As always, it’s an individual thing.
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* Google nightlight leukemia to find some of the other concerns raised about low levels of white light at night, from four years or so ago.
One hit links to a 2004 public relations/thinktank site attack piece flaming pointyheaded scientists who are trying to force your children to sleep in complete darkness (bogus, of course, amber light’s safe) — a frothing defense of the free market for white nightlights keeping children safe from fear of monsters and scientists trying to make your babies sleep in total dark (sigh).
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The amber LED night lights I’ve been using are nice; I’ve also found Ace Hardware is stocking little neon-amber nightlights (two on a card, little white plastic bumps that plug in and glow, very inexpensive, very low power, plenty sufficient if you have one or two per room to avoid falling over the cat in the dark).
======Now, a probably useless attempt to answer your questions:
ight can be measured as photons of a single color, or averaged “white” light, and several ways.
— energy consumed at the source (watts)
(incandescent less efficient than fluorescent; LED in between, though LEDs are catching up fast in energy efficiency for the light produced)
— brightness measured at the eyeball (lux, I think)
— brightness of a known source measured at a specific distance (foot-candle, the brightness of one ‘standard candle’ at one foot distance — no doubt a pre-Metric measurement like furlongs per fortnight).
Let’s compare it to lighting we know about and see if that helps.
moonlight (which is highly variable, as this page makes clear).
http://home.earthlink.net/~kitathome/LunarLight/moonlight_gallery/technique/moonbright.htm
“… with an “average” full moon …. the moonlight brightness would be 0.0269 foot candles (0.290 Lux, or a photographic LV=-2.8) ….”
Here’s a proposal to use 30 lux of blue light to affect circadian rhythms (this would be to make the day/night change more definite and clear, for adults in elder care settings who may have disrupted sleep due to lack of daylight/dawn/sunset light cues, I think)
http://lrt.sagepub.com/cgi/content/abstract/40/2/153?ct
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Bottom line? I’m sticking with amber LEDs
This remains the best page I know. If it’s safe for baby turtles, it’s safe for us.
http://www.floridaconservation.org/seaturtle/WildlifeLighting/index.htm
Thanks again, Hank.
http://www.newscientist.com/article/dn14117-circadian-eye-could-be-key-to-insomnia.html?DCMP=ILC-hmts&nsref=news6_head_dn14117
Yes, the pharma folks are suggesting maybe they can develop and patent a wonderful new drug that could reset these sensitive cells in the eye for doctors to prescribe, to fix sleep problems.
One that would work almost like, duh, light.
Crazy world, this.
Thanks, good one. “So far no one has shown that a broken ‘circadian eye’ causes sleeping problems in humans, but Hattar suspects it’s a matter of time.” (Ha ha at the pun.)
Have you read up on intrinsically photosensitive retinal ganglion cells (iPRGCs), which are essentially what that article was about though they didn’t use that term? They are cells that detect light without vision and communicate with the suprachiasmatic nucleus. My personal theory, and I stress both personal and theory, is that they are key not only to some sleep rhythm disorders but also bipolar disorder.
Lithium and valproate are the only drugs that affect a certain timekeeping protein (its name forgotten at the moment) and are also the most effective mood stabilizers. And, we know that blue light effectively treats seasonal affective disorder (SAD) which is a variant of bipolar.
I can’t help but think all these dots might be connected. In time…
Sandra, good suggestion for a search. Google:
http://www.google.com/search?q=intrinsically+photosensitive+retinal+ganglion
Scholar, recent only:
http://scholar.google.com/scholar?hl=en&lr=&safe=off&scoring=r&q=intrinsically+photosensitive+retinal+ganglion&as_ylo=2007
That’s definitely more reading to do. I think this is the same kind as the identified receptor for blue light, but I already see mention of several different types just looking at the search result page! Different innervations? have to read more.
And here’s yet more fresh science!
http://www.sciencedaily.com/releases/2008/07/080716111409.htm
Brief excerpt below:
“… ecological studies to measure human light exposure are virtually nonexistent, making it difficult to determine if, in fact, light-induced circadian disruption directly affects human health.
LRC researchers have created a small, head-mounted device to measure an individual’s daily rest and activity patterns, as well as exposure to circadian light — short-wavelength light, particularly natural light from the blue sky, that stimulates the circadian system. The device, called the Daysimeter, was sent to 43 female nurses across the country to measure their daily exposure to circadian light, according to Mark Rea, director of the LRC and principal investigator on the project.
The Daysimeter was worn for seven days by both day-shift and rotating shift nurses and then returned to the LRC for analysis. Simultaneously, Rea and his colleagues studied the effect of irregular light exposure to the circadian system of 40 rats, in order to determine if the relationship between circadian disruption and health outcomes could be uncovered using rodent models….”
Meanwhile I wonder if anyone’s counting the trend in total advertising pages for sleep drugs and total sales, and plotting those against changing use of fluorescent lights (sigh)
That would make a good chart, agreed. A quick search revealed: “In 2007, 290 million CFLs were sold, and the special energy-saving bulbs now account for approximately 20% of the American light bulb market. … The sale of CFLs has been on the rise since 2006, when their market share jumped from 5% to almost 11%.”
http://www.eere.energy.gov/news/news_detail.cfm/news_id=11520
Sales of sleep aids are a bit harder to quantify, since they’re not only prescriptions. I found a big market report on the U.S. sleep industry, but being market research it’s quite expensive to access.
That Daysimeter study sounds great!
Much reading to do on ipRGCs.
Arrrrgh. Pharma PR …
http://health.nytimes.com/ref/health/healthguide/esn-insomnia-ess.html?ref=health
“…Rozerem,… which targets receptors in the brain for the sleep hormone melatonin, represents the first new class of sleep medication in several decades.”
Without the slightest hint there’s this big news in nonpharmaceutical melatonin regulation in the past few years.
Makes me wonder, sometimes, how they can go on producing this stuff and calling it ‘news’.
It’s somewhat disappointing coming from the NYT. Something more encouraging (though without as big an audience) was a recent episode of Penn and Teller’s Bullsh*t: Sleep, Inc.. Dr. Daniel Kripke is in it, talking about problems with sedatives, while some quack types are exposed.
BTW, have you seen that Rozerem TV commercial? Weirdness…
[From the studies I've read on Rozerem, it doesn't seem to be much more effective than melatonin supplements. Which is not very.]