Sort of OT, but this reminds me of a question I've not been able to find an answer for on blue light and sleep. (OT because the article says nothing about blue light).
One way light affects sleep is via the intrinsically photosensitive retinal ganglion cells (ipRGCs). These are a third kind of photoreceptor in our retinas, distinct from the more well known rods and cones. These are most sensitive to blue light. They signal the suprachiasmatic nucleus (SCN) in the brain with information about the amount of light they are receiving. The SCN controls circadian rhythms, and uses the changes in light as the day ends as reported by the ipRGCs to do things like to keep things that should be synchronized to the day/night cycle in sync.
Blue light in the evening can mess this up because it makes it look like it is still daylight, as far as far as the SCN can can tell from what it gets from the ipRGCs.
What I have not found anywhere is whether this is based on absolute or relative amount of blue light. Does the SCN look for blue light to fall below a certain fixed threshold, or does it do something like note the peak level of blue light during the day, and then look for the blue light to fall below a certain fraction of that?
The reason this matters is that more and more of our devices that we want to use in the evening supply blue light. We try to counter that by adding features that change the color spectrum in the evening to something with less blue. But that doesn't always work. Computers usually can do it, and often so can tablets and phones. I don't think many TVs have such a setting, though.
If the SCN works with absolute levels, fixing the devices (or wearing blue light filtering glasses) might be the only answer if you aren't able to stop using your devices in the evening.
But if it is based on relative levels, keyed off the peak daytime level...then instead of fixing all the devices it might be possible to address the problem by greatly boosting blue levels in the middle of the day, so that your evening device levels will be far enough down from the peak to not affect anything.
IIRC from reading papers, there seems to be a dose-response effect, both w.r.t intensity and match to peak sensitive wavelength (~465nm). Even green light has some effect.
Avoiding blue light at night after you go to sleep is definitely an under-appreciated problem, especially for folks that stay up late. If you have a habit of going to bed at 2:30am, and the sun rises at 5:30am and comes in your window, you're getting blue light during your circadian night (enough light can make it in through your eyelids to be a problem) -- this may screw up your sleep schedule.
No. Not at all - you do want blue light in the day, that too helps keep your clock regular. (A constant morning time is crucial.) But all that won't compensate for blue light stretching into the evening.
Even way more red light at the same time as some blue light in the evening, while it helps reduce the effect of the blue, isn't fully effective.
I haven't done any rigorous science, but having zero screen time at least 2hrs before sleep and having warm orange lighting definitely allows me to have long uninterrupted sleep. Heavy screen usage before bedtime has the same effect as drinking on my sleep patterns.
I grew up sleeping in pitch black darkness, and having lived now for a while in the Nordics, where summer nights are light and curtains are mediocre at best, I can share that feeling.
I wonder if the higher rates of depression here may have something to do with this (interestingly, I remember reading somewhere that suicides in the Nordics peak in Springtime).
They are fairly common throughout most of Central Europe. I stayed in apartment a few years ago that had electric shutters; it felt like I was living on a space ship.
Should we assume that the light itself is causing the depression? Or should we assume that the light leads to poor sleep, and then the poor sleep is what triggers the depression?
I've spent prolonged periods living away from artificial light. In such situations, the lunar cycle has a profound effect on your psychology and sociology. New moons are quiet times, and wildest parties happen at full moon. Makes me think that "lunatic" is probably a very, very, very ancient concept.
>I just wonder about how actually natural a pitch black sleep is.
"Pitch black" is another thing entirely, but the moon is much dimmer than the light levels this study reports as causing depression (5 lux). And it's pretty dim (equivalent to stray light from a streetlamp).
>The intensity of moonlight varies greatly depending on its phase, but even the full Moon typically provides only about 0.05–0.1 lux illumination
I added a real blackout curtain to my room and really noticed a difference in the quality of my sleep and my general mood. It was designed to really black out all light... https://www.amazon.com/gp/product/B003ZJ88DY/
Skimming the original study, it talks about subjects opening and closing their eyes, so I would very much assume that it's entirely related to seeing light (and not about absorbing light through the face or body).
If you get a sleep mask, be sure to look for one designed to not put pressure on your eyes, which are not hard to find if you seek it out. The cheap ones you get at pharmacies and dollar stores put direct pressure on the eyeballs and it's a wonder that anyone can tolerate them and are perhaps even harmful.
Weirdly, we now know that even the brain has light receptors. (The skull is very transparent when wet with CSF.) Night nurses know that a flashlight hitting a sleeping patients leg in darkness causes a contraction.
Sleep masks help a lot - but they aren't a full solution.
I currently sleep in a room with zero natural light.
I can't tell you whether this makes me more or less likely to be depressed (I think it pales in comparison to other things in my life), however I do always keep a low light on -- without this, it would be very difficult to find my bearings when I wake up.
Also, it is extremely difficult to wake up when it's completely pitch-black.
Slightly off-topic: I've noticed if I work all night (e.g. yesterday writing a paper proposal for a conference), and I manage to stay up all the way until dawn, I literally get euphoria once Sun glances through windows. I can be super tired, but it shots my mood up considerably.
Actually, they didn't touch the lights at all, they only measured the lights that people already were exposed to. They write that "an interventional method, such as a randomized controlled trial using a LAN exposure, is not possible because of ethical concerns".
I think a lot of studies like this are just wrong. When I was a kid, I couldn't sleep without a light on because I'd get depressed. So later on in life if I didn't remember that, I'd think that I just had a light on and now I'm depressed. I think depressed people like a little light.
Much like they say red meat causes cancer, I don't think it's the red meat. I think it's how it's cooked. Red meat is usually barbecued and that char is what could be causing the cancer.
I kind of agree about the light. Everyone I know that needs some light on during the night needs it because of some problem. Either the person is afraid of being in total dark, which is a sign of anxiety and is associated with depression, or have some other problem.
I don't like sleeping with the lights on, but it became a necessity because I have frequent sleep terrors where I wake up confused in the middle of my room. A light helps me understand what's happening and where I am faster, and I don't collide into things as much. Sleep terrors are associated with some mental problems, so there would be a correlation between mental problems and the fact that people have the lights on too (considering I'm not the only one who does that), but both things are not causally connected.
Maybe a bit OT, but my understanding of meat causing cancer is that if you don’t eat enough fiber to clear out the intestinal sludge then it harbors the conditions for cancerous cells to come about. I need to follow up on that more. Even more OT, but it’s irrelevant now as I took a break from meat a year ago after my Plated boxes piled up over the holidays and I couldn’t eat it fast enough . I noticed how supple my body was after a while and got to questioning the food industry and finding too many answers related to my health that I didn’t like. Eating enough seasonal fruit is beneficial in any case, the water clears out toxins. Good point about meat char, seems minimal compared to gunk buildup from an overall health perspective. I dunno if we really thrive as meat eaters anyway, given my health then and now.
>So later on in life if I didn't remember that, I'd think that I just had a light on and now I'm depressed.
What? Anyway, this study has strict definitions of what "depression" is, and I doubt whatever you felt as a child would qualify.
>Much like they say red meat causes cancer, I don't think it's the red meat. I think it's how it's cooked. Red meat is usually barbecued and that char is what could be causing the cancer.
They say eating red meat may cause cancer. Even if your guess is true, they would still be right as red meat is often barbecued. And as a larger point, thinking something like this is true doesn't matter until you get evidence for it.
What I don't like are the "solutions" they propose: noise? use earplugs, light? use curtains. Well I will not be able to sleep if I have something in my ears and if you pull the curtains then you can no longer wake up naturally with the Sun. How about changing your lifestyle so that you can have silence and dark during the night and light in the morning without any "devices". You might have to quit your job :)
1. I've never done this. Not as a child, not as a teen, and not as an adult. I'm nearly 40. I can get myself to wake between 9 and 10 with an alarm, 11 or noon without.
2. I live too far north for this to be reasonable. December days are around 4.5 hours long. Summer nights don't actually get dark here. The sun goes down and stays just below the horizon, so there is a few hours of twilight. You can read outside if the sky is clear.
I doubt that you wake up naturally with the Sun. Where I live the difference between Winter sunrise and Summer sunrise is about 6 hours. Most people keep more regular hours throughout the year.
According to [1], the difference between between winter and summer where I live is rather severe -- varying from 12 hours night and 7.5 hours daylight in winter to zero hours of night (I've read outside with no artificial light in those conditions - there's still quite a lot of light) and 17 hours of daylight in summer. Sunrise varies from 4:30am to 8:30am. I'm not sure most lifestyles can manage that sort of swing through the year.
> those exposed to more than five “lux” of light each night had higher rates of depression
Light can be measured, depression cannot. It barely even has a definition, let alone quantifiable rate. I'd sooner believe that auto-playing videos had a stronger link to depression than lux.
Random theory... Maybe depressed people are highly sensitive to the world's problems/suffering both in immediate and wider environment, their antennae picks up this instability that manifests as internal trauma, anxiety etc. Someone should do an experiment to see if isolation for a few weeks influences depression rate; avoidance of all news, no phone, no internet, no people. Get ready for "Study finds extreme boredom effective anti-depressant".
[+] [-] tzs|8 years ago|reply
One way light affects sleep is via the intrinsically photosensitive retinal ganglion cells (ipRGCs). These are a third kind of photoreceptor in our retinas, distinct from the more well known rods and cones. These are most sensitive to blue light. They signal the suprachiasmatic nucleus (SCN) in the brain with information about the amount of light they are receiving. The SCN controls circadian rhythms, and uses the changes in light as the day ends as reported by the ipRGCs to do things like to keep things that should be synchronized to the day/night cycle in sync.
Blue light in the evening can mess this up because it makes it look like it is still daylight, as far as far as the SCN can can tell from what it gets from the ipRGCs.
What I have not found anywhere is whether this is based on absolute or relative amount of blue light. Does the SCN look for blue light to fall below a certain fixed threshold, or does it do something like note the peak level of blue light during the day, and then look for the blue light to fall below a certain fraction of that?
The reason this matters is that more and more of our devices that we want to use in the evening supply blue light. We try to counter that by adding features that change the color spectrum in the evening to something with less blue. But that doesn't always work. Computers usually can do it, and often so can tablets and phones. I don't think many TVs have such a setting, though.
If the SCN works with absolute levels, fixing the devices (or wearing blue light filtering glasses) might be the only answer if you aren't able to stop using your devices in the evening.
But if it is based on relative levels, keyed off the peak daytime level...then instead of fixing all the devices it might be possible to address the problem by greatly boosting blue levels in the middle of the day, so that your evening device levels will be far enough down from the peak to not affect anything.
[+] [-] RoboTeddy|8 years ago|reply
Avoiding blue light at night after you go to sleep is definitely an under-appreciated problem, especially for folks that stay up late. If you have a habit of going to bed at 2:30am, and the sun rises at 5:30am and comes in your window, you're getting blue light during your circadian night (enough light can make it in through your eyelids to be a problem) -- this may screw up your sleep schedule.
[+] [-] n1000|8 years ago|reply
[+] [-] Nomentatus|8 years ago|reply
Even way more red light at the same time as some blue light in the evening, while it helps reduce the effect of the blue, isn't fully effective.
[+] [-] sitkack|8 years ago|reply
[+] [-] davidw|8 years ago|reply
https://blog.therealitaly.com/2007/08/09/window-technology/
[+] [-] tincholio|8 years ago|reply
I wonder if the higher rates of depression here may have something to do with this (interestingly, I remember reading somewhere that suicides in the Nordics peak in Springtime).
[+] [-] fyfy18|8 years ago|reply
[+] [-] r00fus|8 years ago|reply
[+] [-] lkrubner|8 years ago|reply
[+] [-] Herodotus38|8 years ago|reply
I just wonder about how actually natural a pitch black sleep is.
[+] [-] nkoren|8 years ago|reply
[+] [-] Turing_Machine|8 years ago|reply
Werewolves, "lunatics", etc.
https://en.wikipedia.org/wiki/Lunatic
Just a speculation.
[+] [-] schiffern|8 years ago|reply
"Pitch black" is another thing entirely, but the moon is much dimmer than the light levels this study reports as causing depression (5 lux). And it's pretty dim (equivalent to stray light from a streetlamp).
>The intensity of moonlight varies greatly depending on its phase, but even the full Moon typically provides only about 0.05–0.1 lux illumination
https://en.wikipedia.org/wiki/Moonlight
[+] [-] thinkingemote|8 years ago|reply
But I'd think that humans have always had shelter. Or is there evidence of communities sleeping out in the open?
[+] [-] brianpan|8 years ago|reply
[+] [-] Nomentatus|8 years ago|reply
[+] [-] unknown|8 years ago|reply
[deleted]
[+] [-] jimnotgym|8 years ago|reply
I just added this
[+] [-] gargarplex|8 years ago|reply
[+] [-] icebraining|8 years ago|reply
[+] [-] navjack27|8 years ago|reply
[+] [-] computator|8 years ago|reply
If you get a sleep mask, be sure to look for one designed to not put pressure on your eyes, which are not hard to find if you seek it out. The cheap ones you get at pharmacies and dollar stores put direct pressure on the eyeballs and it's a wonder that anyone can tolerate them and are perhaps even harmful.
[+] [-] Nomentatus|8 years ago|reply
Sleep masks help a lot - but they aren't a full solution.
[+] [-] lhnz|8 years ago|reply
I can't tell you whether this makes me more or less likely to be depressed (I think it pales in comparison to other things in my life), however I do always keep a low light on -- without this, it would be very difficult to find my bearings when I wake up.
Also, it is extremely difficult to wake up when it's completely pitch-black.
[+] [-] chrisper|8 years ago|reply
[+] [-] DoreenMichele|8 years ago|reply
[+] [-] Nomentatus|8 years ago|reply
[+] [-] bitL|8 years ago|reply
[+] [-] mrfusion|8 years ago|reply
[+] [-] icebraining|8 years ago|reply
[+] [-] homero|8 years ago|reply
Much like they say red meat causes cancer, I don't think it's the red meat. I think it's how it's cooked. Red meat is usually barbecued and that char is what could be causing the cancer.
[+] [-] Sohakes|8 years ago|reply
I don't like sleeping with the lights on, but it became a necessity because I have frequent sleep terrors where I wake up confused in the middle of my room. A light helps me understand what's happening and where I am faster, and I don't collide into things as much. Sleep terrors are associated with some mental problems, so there would be a correlation between mental problems and the fact that people have the lights on too (considering I'm not the only one who does that), but both things are not causally connected.
[+] [-] harlanji|8 years ago|reply
[+] [-] boomboomsubban|8 years ago|reply
What? Anyway, this study has strict definitions of what "depression" is, and I doubt whatever you felt as a child would qualify.
>Much like they say red meat causes cancer, I don't think it's the red meat. I think it's how it's cooked. Red meat is usually barbecued and that char is what could be causing the cancer.
They say eating red meat may cause cancer. Even if your guess is true, they would still be right as red meat is often barbecued. And as a larger point, thinking something like this is true doesn't matter until you get evidence for it.
[+] [-] jk2323|8 years ago|reply
Try thinking again: http://www.yourstylishlife.com/german-nobel-laureate-shocked...
[+] [-] Nomentatus|8 years ago|reply
[+] [-] unknown|8 years ago|reply
[deleted]
[+] [-] analogic|8 years ago|reply
Lol, everytime I see that domain all I can think of is it being the place where Infoseek went to die.
[+] [-] hawski|8 years ago|reply
22. ▲ The antidepressant effect of sleep deprivation (mosaicscience.com)
389 points by onuralp 1 day ago | flag | hide | 135 comments
[+] [-] GoToRO|8 years ago|reply
[+] [-] Nomentatus|8 years ago|reply
[+] [-] Broken_Hippo|8 years ago|reply
[+] [-] GoToRO|8 years ago|reply
[+] [-] Broken_Hippo|8 years ago|reply
1. I've never done this. Not as a child, not as a teen, and not as an adult. I'm nearly 40. I can get myself to wake between 9 and 10 with an alarm, 11 or noon without.
2. I live too far north for this to be reasonable. December days are around 4.5 hours long. Summer nights don't actually get dark here. The sun goes down and stays just below the horizon, so there is a few hours of twilight. You can read outside if the sky is clear.
[+] [-] icebraining|8 years ago|reply
Regarding light, if you want morning sunlight, motorized curtains with a timer are cheaper than moving.
[+] [-] cup-of-tea|8 years ago|reply
[+] [-] stordoff|8 years ago|reply
[1] https://www.timeanddate.com/sun/uk/sheffield
[+] [-] musage|8 years ago|reply
[deleted]
[+] [-] exodust|8 years ago|reply
Light can be measured, depression cannot. It barely even has a definition, let alone quantifiable rate. I'd sooner believe that auto-playing videos had a stronger link to depression than lux.
Random theory... Maybe depressed people are highly sensitive to the world's problems/suffering both in immediate and wider environment, their antennae picks up this instability that manifests as internal trauma, anxiety etc. Someone should do an experiment to see if isolation for a few weeks influences depression rate; avoidance of all news, no phone, no internet, no people. Get ready for "Study finds extreme boredom effective anti-depressant".