Wearing an eye mask during sleep improves episodic learning and alertness
pubmed.ncbi.nlm.nih.gov
pubmed.ncbi.nlm.nih.gov
Clearly the sleeper knows if they are wearing an eye mask with holes that let in light, or if they are wearing a complete eye mask.
I work in the neurotech/sleeptech space, and it should be possible to do this study in a double blind method.
In a sleep lab, with EEG, monitor the users sleep state. When they are in any non-wake state ambient light could be brought into the room. In one instance, no light is applied, in another light is applied. Don't use the usual camera's that are used in a sleep lab. In such a method the trial is double blind, but also much more expensive than the method used.
Life isn't a double blind randomised placebo controlled study.
There is no group consisting entirely of me I can control for.
Also, an absence of ambient light isn't the same as wearing a sleep mask. The home user can't enter a sleep lab and wear electrodes as a convenience.
I agree that it could be something other than the mask. For instance, it could be that it is the simple matter of having them try something that led to an increase. But I'm not as clear on how this is an obvious "flaw" with the study.
Or are you saying you would want the double blind to fully rule out light, and we would be back to asking "why did the masks do something?"
This tells you something different than “ambient light while sleeping negatively impacts learning.”
That is, if you did manage to "double blind" it and got no difference in treatments, that means we don't understand the mechanism in this study. It does not, necessarily, mean that there are no results in this study. RIght?
Yes, we have evidence that this influences things. That is usually why people replicate without telling people why they were doing something. In this study, they didn't say "we are testing you with masks to see if they make you test better." It was more, we are testing you with and without masks to see if we spot differences. I could easily envision some folks expecting the result to go the other way.
More, if that is the concern, you need to test doing that. Don't make it blind, reverse the message. Tell them you expect them to be less alert wearing a mask, and see if that holds.
Right?
My question is ultimately on whether that is a flaw in this study, or more to study? :D I'm probably placing too much weight on the word "flaw?"
But seriously the only ways off the top of my head to mobilize placebos is to lie to people which doesn’t seem worth the squeeze. They just lead to more misconceptions.
But that's literally what marketing does, not just for supplements, but in general. The limits of what can be achieved through lies and persuasion are well-mapped now. There is a tension between what marketers would like to do, and what the law allows them to, but it's a tension over marginal effectiveness - the illegal methods are only slightly more effective than the legal ones. There are no psy-corps placebo mind control superpowers, known or hypothesized - if there were, then regulations around advertising and fair competition would look more like regulations around access to enriched fissile material or highly infectious pathogens.
And there has been research into what provides a stronger placebo effect. Getting a shot gives more of a placebo effect than a pill for example.
I'm not in favor of lies. But mayhap shutting up is more called for? :)
Our mind controls our body, which has strong healing capabilities.
>I'm not in favor of lies. But mayhap shutting up is more called for? :)
I don't get what you're saying here.
Edit: I am slow to realize it may have sounded like "shut up" was directed at you. My apologies. I meant that more for the generic voice of caution that is as often very valuable. And i am very nervous on what it implies for general health reporting. How many more people are sick because they think they should be? What can you even do with that idea?
>And i am very nervous on what it implies for general health reporting.
Remember that it works both ways. For everybody that gets a fake flu, there's somebody who is healthier because they ate their spinach.
That is, if we were to reduce the negative effects reporting, but increase the positive ones, would that bias the world in that direction? (That make sense?)
Are they though? I used to think so until I skimmed Wikipedia article on placebo some 5 minutes ago. According to the article (as of now), there's been plenty of research on placebo done in the past couple decades, which revealed... the most mundane reality you'd expect: placebo effect impacts perception of symptoms, and can only do as much as a transient change in perception can. Apparently, the old studies that ascribed all kinds of big effects to placebos, were failing to account for regression to the mean.
Now, I haven't checked the sources, but I'm inclined to believe it - it feels right. The possibility of placebos being meaningfully effective on the targeted condition itself felt like bad writing[0] - the same phenomenon should be giving us all kinds of superpowers, which we don't see. I mean, when you get drunk, you may tolerate pain better, but your skin doesn't turn into kevlar with steel inserts just because the drunk you believes you're impervious to knives and bullets.
--
[0] - Like in fiction, when you discover the author didn't think through the consequences of a minor plot point they're making - a plot point that, extrapolated ever so slightly, would instantly break the main story, and/or disrupt the entire fictional universe.
That said, I don't know?
The progressive take is placebo should be considered valuable information and not ignored.
As for exploiting the perceptual aspects for good and bad, well, that's a really really well-explored ground - we've been at it for thousands of years. Religion, folk medicine, homeopathy, or the modern bullshit fads like fitness, healthy food, spiritual exercise philosophies, etc. - they all build up huge emotional frameworks around core interventions that, by themselves, have slight to no effect. They are big money printers, tho.
> Sleep diary data revealed no differences in the number of hours slept while wearing the eye mask (7.15 ± 16.66) or the control mask (7.18 ± 16.82; t(23) = −0.11, p = .914, N = 24). Likewise, there was no significant difference in self-rating of sleep quality (eye mask: 3.13 ± 0.19 vs control: 2.84 ± 0.16; Z = −1.53, p = .131, N = 31).
Another possibility might be to design the functionality into the mask itself. When it detects the user is asleep, it could open up to let in light (or not) based on which cohort the user is in.
The detection could be done by having sensors in the mask itself, or it could just pair with the user's existing fitness/sleep tracker of choice via Bluetooth.
Are we to assume that this study excludes these two additional cohorts, and if so why or how has that been established?
A true test of placebo effect must be one where you'd have a group who does not use a placebo, and a group that does! But then how would you study it blind?
Maybe a better (and possible) test would be to give everyone the placebo, but divide participants into three groups. One would be told they're given a real treatment, the other would be told they're given a placebo for the real treatment, and the third would be told they're given a sugar pill for no specific reason other than to see what happens.
1+2 would then tell you about whether or not knowing if you're getting a real treatment or placebo matters; 2+3 would tell you how much knowing you have a problem to treat in the first place matters.
It seems important to eliminate that possibility, because otherwise sleeping mask or not literally doesn't matter and it's just about doing something and the study is simplified to "caring about sleep improves sleep". Which can be totally true even if bollocks per western medicine tradition to date, but then the study should be about that and not about sleeping masks eh?
Disputed, especially how significant it is...
Not by this study about masks I guess
Are the sleepers not blinded by the eye masks?
/s
Well, the group wearing the eye mask was effectively blind for the night
I seriously cannot sleep without doing this now. The feeling of light incident on my closed eyelids while trying to sleep is quite uncomfortable.
My only problem now is that my CPAP mask is transparent, and so some light bleeds through there. If I could find an opaque CPAP mask, then I would be able to block out all outside light. As it is, I find that putting a pillow over my head over the CPAP mask blocks out most of the rest of the light that would otherwise get through the mask, and because of the CPAP mask I am still able to breathe underneath the pillow.
I can tell you, it makes a huge difference for me to be able to block out the light. Almost as much of a life-changing event for me as getting the CPAP in the first place.
I'm assuming your objection is that the research biased the results by informing the subjects that they are testing the effect of sleeping masks on "episodic learning and alertness"?
Similar story with any form of transport, where the various light sources are largely outside your control.
The newer "3D" eye masks provide full blackout and stays on without much trouble. Well worth keeping in a travel kit alongside earplugs.
Anyone know of research showing the effectiveness of varying levels of darkness in a room, from complete blackout to fairly dim?
I can imagine a slightly larger one that extends over the eyes - if I can find one, I will buy it.
No experience with it but sounds like the kind of thing you're after.
the pro one, not the one you linked (headphone inserts seem like needless ear pressure): https://mantasleep.com/products/manta-sleep-mask-pro
i toss and turn all night and this thing stays on most of the time, is incredibly comfortable, and i am so grateful i received it as a gift (would never have bought for self)
Have you tried the Silk one? I'm tempted to get that one instead of the Pro since the materials sound nicer, but the site is really unclear about the differences...
After trying about 10 other sleep masks, I ended up with the Alaska Bear Silk Two Strap [1] which has straps so thin they're imperceptible, and a much more effective retention mechanism, for a fraction of the price.
[1] https://www.amazon.com/ALASKA-Natural-Blindfold-Super-Smooth...
/s
As a side sleeper, I can't use masks with speakers or even long ear plugs, as they put enough pressure on my ear cartilage that they make sleep uncomfortable.
https://www.ebay.com/itm/194063513469
If you do find it useful then it's worth spending the money to get the best available, but I use the cheap one and it's great.
It's pretty much exactly what you're describing. My only complaint is that the velcro wears off after time and it stops sticking.
So of course the eye mask isn't necessary at all, reducing the ambient light is the key. Mask is one option, but black out curtains (in most areas) and eliminated or shielding any light emitting devices in the room is key.
I use small strips of electrical tape to block led lights from small appliances I keep in my bedroom. I wish more companies were thoughtful in reducing the amount of light their electronics emit in a default state.
[1] buff.com
A shirt drapes comfortably, it fits you easily and snugly without pulling too tight, it's also always available
They’re really soft and comfortable as an eye mask and don’t get too hot or slip off. There’s no elastic stream involved and it’s really slimline so you barely feel it. Also they’re cheap!
I use a dark coloured one and fold it over 2 or 3 times to make it darker. Couldn’t sleep without it, nor could a few people who I’ve introduced to it!
[1] buff.com
If yes... they seem o sell it in full and half size. Do you use the half size? a full one folded in two?
(I am curious to see what it does for me but I do not use this kind of products normally so I would like to avoid buying the "wrong" type).
TIA
I had no idea they had such a large range! I just use a basic original, full size one, made out of thin material. Full size means you can fold it over two or three times to make it block out more light, I'm not sure a half size would work so well but I've never tried one.
I think it would be the "Original EcoStretch" model, though I can't say for 100% certain as I bought mine in an outdoor wear shop and just bought the cheapest, thinnest, darkest one.
Thanks!
I've gotten so habituated to it that I almost can't fall alseep without one.
I used a little bit of sewing to tighten up the fit exactly to my head and it never falls off and is incredibly comfortable.
No sound though.
I could still stay up on my phone before deciding to sleep and then put the mask on?
They're to help you get into your sleep state and stay unimpacted by artificial light once you've decided to sleep.
If you are struggling to sleep because you stay up on your phone, you have bigger problems that aren't the job for a sleep mask.
https://pubmed.ncbi.nlm.nih.gov/36521010/#&gid=article-figur...
(1) the truncated axes hide what a small effect size it seems to be and (2) even though they state the p-value is significant, eyeballing it there seems to be a really wide variance that is almost overlpaping b/w the two situations.
It seems to me like a marginally significant result with a very small effect size.
Now, I make no claims that it is necessary to be that dark. I have no idea.
In old experiments, just the light coming in under a door diminished melatonin in mice.
https://www.sleepfoundation.org/physical-health/sleeping-wit...
The mechanically or electrically-closed rolling shutters called "Rolladen" in German, and installed on all but the cheapest new construction in Europe: when properly installed, those things can black out a room with the sun shining directly through the window.
I don't get the fake shutters in North America. Especially the ones that wouldn't even cover the window if they could move.
https://www.lasexta.com/viajestic/curioso/que-paises-extranj...
Logic dictates that very likely wearing the mask has no effect at all, and it is in fact other factors influencing quality of sleep. It would make sense to look into those, and it is very surprising it was not already done from the beginning.
E.g. Obviously a participant can not use their mobile phone or other screen devices if they are wearing a mask, and the mere fact they are wearing the mask may force them to do the one thing they can do: sleep.
In other words, it could simply be that the mask itself incapacitated and prevented other activities from being carried out by the participant. Equal or better results can be achieved if participants are told to concentrate on sleeping. Heck, you might even pay them just to sleep so they do not stress about the fact they have to waste time sleeping – this alone should yield some interesting results.
My advice: forget the silly mask.
What logic dictates that?
This sounds like you describing the mechanism rather than rejecting the idea that a sleep mask helps. IOW, it may help because it "enforces" better sleep hygiene.
Light blocking, phone being harder to use and crafting some sort of sleeping ritual can all be achieved by using it.
Secondly, you raise lots of interesting hypotheses that might contradict the findings of the study. These would indeed be interesting directions for further similar studies. However, in the meantime, a study (even of moderate evidence quality) is probably more valuable than off-the-cuff hypotheses.
(My low quality n=1 anecdote: i’ve discovered that I am quite light sensitive while sleeping. so measures which minimise ambient light improve my quality of sleep. Whether this is blackout curtains or a sleep mask is more situationally dependent.)
But they didn't test for that here.
The studies conclusion seems to be blackout curtains either cost $$$ or take a bit of effort to install, mask is cheap/easier.
Sleep is good, people sleep better when as much light is blocked as possible. It's a conclusion that is known.