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Study: Closed-eye perception of brightness is significantly stronger than previously thought
Medical Xpress / Osaka Metropolitan University / Color Research & Application ^ | Dec. 19, 2022 | Professor Hideki Sakai

Posted on 12/20/2022 2:42:41 PM PST by ConservativeMind

Can't sleep when your partner is on his or her smartphone? This may not be oversensitivity on your part; your eyelids probably deserve some of the blame. A scientist from shows that eyelids transmit much more light than previously thought.

Sleep deprivation and sleep disorders are detrimental to health and interfere with daily life. Studies have been conducted to elucidate the mechanisms underlying various factors that affect sleep. One major factor is the lighting environment. Changes in light exposure during the daytime and nighttime or during sleep have been reported to influence circadian rhythms and sleep quality.

Although several studies have been carried out to measure eyelid transmittance, experimental conditions differed significantly from lighting environments in daily life.

Professor Hideki Sakai applied a new method to measure the light transmittance of the eyelids when the eyes are shut. His results indicate that closed-eye perception of brightness is remarkably stronger than previously reported.

Professor Sakai conducted experiments on a total of 33 participants under relatively bright conditions (illuminance of 100 lux) in which each participant's entire face was illuminated. A lighting device was used to increase or decrease facial illuminance, and closed-eye light transmittance was measured by having the participants make adjustments to match the levels of brightness they perceived with their eyes closed and with their eyes open. Monochromatic red, yellow, green, and blue LEDs and a white LED were used as light sources.

The experiment results show that eyelid transmittance values were up to 10 times higher than those (i.e., 0.3%–14.5%) reported in the past. The color of light also made a difference, with red light perceived as brighter and blue light perceived as darker. Additionally, Professor Sakai noted significant differences between individual participants; for some, their perception of brightness remained almost unchanged between the open- and closed-eye conditions.

(Excerpt) Read more at medicalxpress.com ...


TOPICS: Health/Medicine
KEYWORDS:
We really need to block out light well to sleep soundly.

If you have sleeping problems, this is an easy fix, with a comfortable eye mask and reducing other lights in the room. Also, reduce all lighting sources at least an hour before sleeping.

1 posted on 12/20/2022 2:42:41 PM PST by ConservativeMind
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To: Mazey; ckilmer; goodnesswins; Jane Long; BusterDog; jy8z; ProtectOurFreedom; matthew fuller; ...

The “Take Charge Of Your Health” Ping List

This high volume ping list is for health articles and studies which describe something you or your doctor, when informed, may be able to immediately implement for your benefit.

Email me to get on either the “Common/Top Issues” (20 - 25% fewer pings) or “Everything” list.

2 posted on 12/20/2022 2:43:20 PM PST by ConservativeMind (Trump: Befuddling Democrats, Republicans, and the Media for the benefit of the US and all mankind.)
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To: ConservativeMind

I seem to get more sensitive to this the older I get. Never bothered me as a kid, but now, with a bedroom with an eastern exposure, I cannot sleep past sunup unless I can block the light out with a sleeping mask or pillow over my head.


3 posted on 12/20/2022 2:49:35 PM PST by Boogieman
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To: ConservativeMind

I accept the findings of this study but, OTOH, I have no trouble sleeping deeply with max intensity solar irradiance directly on my eyelids (as long as the infrared component is not too strong).


4 posted on 12/20/2022 2:50:33 PM PST by steve86 (Prophecies of Maelmhaedhoc O'Morgair (Latin form: Malachy))
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To: ConservativeMind

I have black-out curtains, and No night light in my bedroom. The only light is the alarm clock, and it’s usually facing slightly away from me.


5 posted on 12/20/2022 2:54:26 PM PST by EvilCapitalist (81 million votes my ass.)
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To: Boogieman
"I seem to get more sensitive to this the older I get."
I'm ninety. I have to wear a sleeping mask at night even though it is uncomfortable because my wife has a different sleeping schedule than I. Some times I pull the covers over my head, but that is uncomfortable also.
6 posted on 12/20/2022 3:04:48 PM PST by Hiddigeigei ("Talk sense to a fool and he calls you foolish," said Dionysus - Euripides)
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To: ConservativeMind

“this is an easy fix, with a comfortable eye mask and reducing other lights in the room.”

That one is ok, but don’t suggest spray-painting eyes black, or it will become a Tic-Tok Challenge.


7 posted on 12/20/2022 3:10:59 PM PST by BobL
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To: ConservativeMind

Don’t need a study to tell me that. Need pitch black or as close as I can get to sleep well.


8 posted on 12/20/2022 4:00:18 PM PST by HamiltonJay
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I can sleep outside in direct sunlight or even with a lit laptop screen facing me no problem. If I have videos playing, I will incorporate everything said into my dreams.


9 posted on 12/20/2022 4:12:40 PM PST by dsrtsage ( Complexity is just simple lacking imagination)
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