In recent years, sleep monitoring apps and bracelets with sleep monitoring functions have sprung up.
Their functions can be said to be various, in addition to measuring the length of sleep, the depth of sleep, some can even let you get up in the morning to harvest your own night of wonderful dream collections...
Image source: Network
I don't know if everyone has such curiosity, the bracelet is just that, the mobile phone and I have no physical contact, how do you know if I sleep well?
At present, there are several methods in the mainstream:
First, sound monitoring through a microphone.
The night is generally the quietest time of the day, when everything is silent and there is basically no noise. At this point, the microphone can monitor your breathing, snoring, and quilting to determine whether you are asleep and how heavy your sleep is.
Of course, your snoring and dreaming sounds are obtained in this way.
Second, monitor your body movements through your phone's "three-dimensional gyroscope," which is how often you turn over or move around.
To put it simply, when you lie in bed with your phone, you move a lot, and the phone moves with you, it thinks you're in a light sleep; if you don't move, it thinks you're in deep sleep.
Third, if it is a bracelet, it is monitored by the above exercise plus heart rate monitoring, while there is generally no sound monitoring.
So the question is, is the sleep quality measured in this way really accurate?
To answer this question, we must first know how to measure energy and measure "accurately".
The gold standard for clinical sleep monitoring is polysomnography (PSG).
It uses electrode patches and nostril intubation to measure the examiner's brain waves, muscle tone, electrocardiogram, blood oxygen saturation, and mouth and nose breathing during sleep to monitor the quality of his sleep in an all-round way.
Look like this:
Image source: Wikipedia
According to EEG fluctuations and eye movements, sleep is divided into 4 stages: light sleep (N1), light sleep (N2), deep sleep (N3), and rapid eye movement sleep (REM).
The proportion of deep sleep is about 20% to 25%, and the proportion of REM is about 25%.
Based on these ratios, the quality of a person's sleep can be roughly judged.
The "light sleep" and "deep sleep" measured by mobile phones are estimated through the estimation of body movement, and many sleep studies have proposed that this estimate is really not very accurate.
A 2015 sleep study of 65 teenagers showed that sleep monitoring software was largely accurate in estimating the time it took to fall asleep and the length of sleep, but it did not do a good job of identifying the different stages of sleep.
Another 2021 study analyzed the results of 495 smartphone apps and 170 wearable devices and found that the correlation between sleep efficiency, wake-up time, light or deep sleep, and PSG was not very good, except for accurate snoring time.
That is to say, although the difference between how long you sleep and how long you snore can be measured, but the quality of sleep, sleep monitoring software really does not count.
We consulted with sleep specialists and also found that in outpatient clinics, people who themselves felt anxious about sleep problems showed more anxiety when they saw the data or scores monitored by the bracelet, which further affected sleep.
It's certainly good to care about the quality of your sleep, or to know if you're snoring or not dreaming.
But if the data of sleep monitoring brings you not peace of mind, but anxiety about not sleeping enough and not sleeping well, then it is better not to use it.
After all, sleeping better and having better sleep is our ultimate goal!
Image source: giphy.com
As it is, the world is wonderful
Curious Tour Stop 070
This article is reviewed by experts
bibliography
[1] de Zambotti, M., Baker,F., & Colrain, I. Validation of Sleep-Tracking Technology Comparedwith Polysomnography in Adolescents[J]. Sleep, 2015,38(9):1461-1468.
[2] Kim K, Park DY, Song YJ, Han S, Kim HJ. Consumer-grade sleep trackers are still not up to par compared to polysomnography[J]. Sleep Breath, 2021.
Planning and production
Planner: Turtle | Producer: Murphy
Illustration source: Figureworm Creative
Cover image source: Dr. Lilac design team