Researchers observed 25 healthy adults, ages 21 to 41, in a sleep laboratory during eight-hour sleep opportunities over seven consecutive nights.
Absurdly low n. Additionally, I've become very skeptical of anything coming out of sleep labs after my wife was sent to one (at a prestigious teaching hospital) by her doctor some years ago: the 'sleep opportunity' was lights out at 9pm for 8 hours, and the staff were wholly indifferent to the fact that she's a night owl and prefers to sleep after midnight. Additionally she reported that it was not particularly quiet or dark.
I am not a fan of noise machines but I have noticed that I sleep best on rainy nights, which has a similar average sound spectrum, and is about the same as the sound of your blood circulating near your eardrums. Testing pink noise along with aircraft noise (which is closer to red noise) is equivalent to just making the noise level higher with slightly more midrange energy. Some noise can be relaxing for light sleepers; too much is just annoying.
The thing that stood out more to me than the n being low is "the participants reported not previously using noise to help them sleep or having any sleep disorders." Sleeping with pink noise seems like something that you'd end up getting acclimated to.
My n=1 is that I often sleep with a fan on and live in NYC -- whenever I stay in a place where there is no noise I tend to have trouble sleeping, so I end up turning on some nature sounds on my phone from myNoise.
Yeah that seems silly. I was a quiet-room sleeper until I met my wife, who needs some kind of white noise to sleep. I eventually adapted and now sleep much better with noise than without (at least subjectively), but that change took a while, at least several months. I found it quite difficult to sleep with for a while.
The low n is not the only questionable thing about the study. What a big n gives you is diversity of samples and tighter confidence intervals, but it can not correct for methodological limitations. Specifically, they didn't invite any people with sleep issues or who are already sleeping under noise. Therefore the conclusion is a "duh" - if you don't require pink noise to sleep, then don't add it.
I’ll match your anecdote. I slept with white noise in my former home which was in a noisier town and felt it improved my sleep. Now that we’ve moved to a nice historic neighborhood I find I sleep best with nothing on at all. The silence there is so wonderful. Maybe silence is the ultimate luxury.
Common sense and experience inform my theory of good sleep: Pitch black, stone quiet, with noise limited to pre-sleep audial approximations of the dream-like mental noise that precipitates sleep.
With some friends we usually go camping near a waterfall and we always try to camp a little further so we don't hear the noise. At least not too much. We always assumed it was related to the fact that you can't hear anything approaching, some kind of primal instinct
This reminds me of an old Wired interview with Danny Hillis when he developed a system called Babble that used unintelligible vocal bits as background sound to help concentration, too bad it never really went anywhere.
https://www.wired.com/2005/06/applied-minds-think-remarkably...
I'm also addicted to the fan but not only for the noise I like feeling the wind in my face, I think that as it also helps lower your body temperature you sleep better
The study may well be flawed—small n, selection bias, lack of proper controls, sure. But can we please stop using personal anecdotes to dismiss scientific inquiry?
Arguments like 'well, it works for me,' or 'I took this med and recovered immediately,' or 'I saw X happen right after a vaccine' are not valid refutations. Science is frequently counter-intuitive and often contradicts our personal experience and gut instincts. That is precisely why we rely on the scientific method and statistical rigor—rather than individual perception—to establish evidence.
This study is tiny and of negligible value. They didn't even try to pretend it's of real value, and instead just dropped the classic "our study clearly demonstrates that people should probably study this stuff". Conditioned norms are by far the most relevant condition for sleep for most people, and sleep studies of tiny durations with tiny sets are basically just noise makers (har har). Even worse, they seem to have specifically excluded people who already use noise machines, ensuring that their participants were conditioned for the silent norm.
Scientific method, statistical rigour...eh, this looks like a headline chasing study.
study aside, pink noise is awful imo - it's perfect if you're calibrating a PA system and need specific power spectral density properties, but bad for my brain. if sleeping somewhere without a fan or whatever i use brown noise, it's closer to a lower rumbling.
This study had no controls at all, and can safely be ignored.
>The participants reported not previously using noise to help them sleep or having any sleep disorders.
All this study said was that people who didn't need noise to sleep had their sleep disrupted when noise was introduced. It has absolutely no implication for people who use noise to help them sleep.
> Participants slept under different conditions, including being exposed to aircraft noise, pink noise, aircraft noise with pink noise and aircraft noise with earplugs
And yet the conclusion is about pink noise vs silence. We may have a new textbook example of HARKing right here!
> The results, the researchers said, suggest not only that earplugs—which are used by as many as 16% of Americans to sleep—are likely effective, but also that the overall health effects of pink noise and other types of broadband noise “sleep aids” need to be studied more thoroughly.
7 nights is not nearly enough to get used to new environmental factor introduced in the study, possibly exacerbating disruption from sleeping in a new place (sleep clinic).
n=25? Seriously?
This is barely passable as an early hypothesis test before you perform an actual study.
I get how difficult a study like this is to carry out, but each participant was involved for just seven days, each night exposed to different conditions. The control environment was silence, and every other conditions did worse than controlled silence. In others they piped in fake environmental noises, pink noise, or made the participants wear earplugs with some other combination.
Eh. People condition to an environment, and someone conditioned to something like pink noise wouldn't have the acclimation issue (and they either specifically selected for people who don't use noise machines, or they just randomly got only people who don't), and it might drown out smaller environmental noises that otherwise would have disrupted their sleep. It would take a much longer study to determine this.
Or hey, maybe those insecure sleep masks tracking EEG and other things will give us some insights eventually. People just need to harvest the data from the other services.
Researchers observed 25 healthy adults, ages 21 to 41, in a sleep laboratory during eight-hour sleep opportunities over seven consecutive nights.
Absurdly low n. Additionally, I've become very skeptical of anything coming out of sleep labs after my wife was sent to one (at a prestigious teaching hospital) by her doctor some years ago: the 'sleep opportunity' was lights out at 9pm for 8 hours, and the staff were wholly indifferent to the fact that she's a night owl and prefers to sleep after midnight. Additionally she reported that it was not particularly quiet or dark.
I am not a fan of noise machines but I have noticed that I sleep best on rainy nights, which has a similar average sound spectrum, and is about the same as the sound of your blood circulating near your eardrums. Testing pink noise along with aircraft noise (which is closer to red noise) is equivalent to just making the noise level higher with slightly more midrange energy. Some noise can be relaxing for light sleepers; too much is just annoying.
The thing that stood out more to me than the n being low is "the participants reported not previously using noise to help them sleep or having any sleep disorders." Sleeping with pink noise seems like something that you'd end up getting acclimated to.
My n=1 is that I often sleep with a fan on and live in NYC -- whenever I stay in a place where there is no noise I tend to have trouble sleeping, so I end up turning on some nature sounds on my phone from myNoise.
Yeah that seems silly. I was a quiet-room sleeper until I met my wife, who needs some kind of white noise to sleep. I eventually adapted and now sleep much better with noise than without (at least subjectively), but that change took a while, at least several months. I found it quite difficult to sleep with for a while.
Perhaps too meta or off topic but I thought it was funny that you thought their n was low and then cited a story about one person.
That is a low n, but I’m not sure what the alternative is. Surely random anecdotes (n=1) are even less powerful?
The low n is not the only questionable thing about the study. What a big n gives you is diversity of samples and tighter confidence intervals, but it can not correct for methodological limitations. Specifically, they didn't invite any people with sleep issues or who are already sleeping under noise. Therefore the conclusion is a "duh" - if you don't require pink noise to sleep, then don't add it.
Random anecdotes might be less biased. For example, no pressure to publish nor sell a product.
I’ll match your anecdote. I slept with white noise in my former home which was in a noisier town and felt it improved my sleep. Now that we’ve moved to a nice historic neighborhood I find I sleep best with nothing on at all. The silence there is so wonderful. Maybe silence is the ultimate luxury.
Sleep labs are like doctors are like mechanics are like restaurants - their only legal obligation is to not kill you,
not be of any particular quality.
Do your homework.
Common sense and experience inform my theory of good sleep: Pitch black, stone quiet, with noise limited to pre-sleep audial approximations of the dream-like mental noise that precipitates sleep.
"Pink noise sounds like a waterfall." https://en.wikipedia.org/wiki/Pink_noise
With some friends we usually go camping near a waterfall and we always try to camp a little further so we don't hear the noise. At least not too much. We always assumed it was related to the fact that you can't hear anything approaching, some kind of primal instinct
Helps me quite a bit to focus when Im in noisy spaces.
This reminds me of an old Wired interview with Danny Hillis when he developed a system called Babble that used unintelligible vocal bits as background sound to help concentration, too bad it never really went anywhere. https://www.wired.com/2005/06/applied-minds-think-remarkably...
For me that would be the worst kind of distraction: always triggered by sounds of communication, never able to recognize what is said.
I suspect not all such statistical results apply uniformly to all people.
A number of noise generators have that sort of nonsensical babble as a component of the sound. For instance
https://mynoise.net/NoiseMachines/cafeRestaurantNoiseGenerat...
Nothing that your mind has enough edges on to try to interpret, but vaguely human-like.
I grew up in South East Asia with air con running all night, when I moved away I found it hard to sleep in 'quieter' countries
I grew up near train tracks. I’m totally of incapable of even hearing trains unless they’re directly in front of me.
This. In summer I get ‘addicted’ to fan noise and cant sleep without. I moved to Asia and the AC is such a blessing.
I'm also addicted to the fan but not only for the noise I like feeling the wind in my face, I think that as it also helps lower your body temperature you sleep better
I noticed I'd feel sleepy after more than half an hour in the server room. Likely the fan noise but the lower temperature might influence it as well.
Unfortunately too expensive and large to set this up in the bedroom to help me sleep nowadays.
It's the dehumidifier for me. Which kills two birds with one stone.
The study may well be flawed—small n, selection bias, lack of proper controls, sure. But can we please stop using personal anecdotes to dismiss scientific inquiry?
Arguments like 'well, it works for me,' or 'I took this med and recovered immediately,' or 'I saw X happen right after a vaccine' are not valid refutations. Science is frequently counter-intuitive and often contradicts our personal experience and gut instincts. That is precisely why we rely on the scientific method and statistical rigor—rather than individual perception—to establish evidence.
This study is tiny and of negligible value. They didn't even try to pretend it's of real value, and instead just dropped the classic "our study clearly demonstrates that people should probably study this stuff". Conditioned norms are by far the most relevant condition for sleep for most people, and sleep studies of tiny durations with tiny sets are basically just noise makers (har har). Even worse, they seem to have specifically excluded people who already use noise machines, ensuring that their participants were conditioned for the silent norm.
Scientific method, statistical rigour...eh, this looks like a headline chasing study.
Sure, you are absolutely right. Even a sloppy study like this still had something useful than any anecdotes.
study aside, pink noise is awful imo - it's perfect if you're calibrating a PA system and need specific power spectral density properties, but bad for my brain. if sleeping somewhere without a fan or whatever i use brown noise, it's closer to a lower rumbling.
This study had no controls at all, and can safely be ignored.
>The participants reported not previously using noise to help them sleep or having any sleep disorders.
All this study said was that people who didn't need noise to sleep had their sleep disrupted when noise was introduced. It has absolutely no implication for people who use noise to help them sleep.
Meaningless trash.
Thanks for sharing. I'll have to reconsider my nightly noise setup, but good to know.
If you're resting well with your current setup, I wouldn't change it. There are so many individual factors involved with good sleep.
> Participants slept under different conditions, including being exposed to aircraft noise, pink noise, aircraft noise with pink noise and aircraft noise with earplugs
And yet the conclusion is about pink noise vs silence. We may have a new textbook example of HARKing right here!
The conclusion is:
> The results, the researchers said, suggest not only that earplugs—which are used by as many as 16% of Americans to sleep—are likely effective, but also that the overall health effects of pink noise and other types of broadband noise “sleep aids” need to be studied more thoroughly.
One of those least-worst choices?
What if the intensity was modulated as a function of the dB of externally sourced sounds?
7 nights is not nearly enough to get used to new environmental factor introduced in the study, possibly exacerbating disruption from sleeping in a new place (sleep clinic).
n=25? Seriously?
This is barely passable as an early hypothesis test before you perform an actual study.
> 25 healthy adults
Come on guys. Replication crisis has been fully documented
I get how difficult a study like this is to carry out, but each participant was involved for just seven days, each night exposed to different conditions. The control environment was silence, and every other conditions did worse than controlled silence. In others they piped in fake environmental noises, pink noise, or made the participants wear earplugs with some other combination.
Eh. People condition to an environment, and someone conditioned to something like pink noise wouldn't have the acclimation issue (and they either specifically selected for people who don't use noise machines, or they just randomly got only people who don't), and it might drown out smaller environmental noises that otherwise would have disrupted their sleep. It would take a much longer study to determine this.
Or hey, maybe those insecure sleep masks tracking EEG and other things will give us some insights eventually. People just need to harvest the data from the other services.