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Your mobile device is scaring away the night valet
You’re feeling a little sleepy, so you put on your PJs and hop into bed.
But you’re not quite ready to disconnect from the world – so you reach for your phone, surf a little, update your status on facebook and watch a video clip, you find in yoga whatsup group….. then you turn off the lights.
Expecting the “sleep fairy”, to pay you a visit.
But, instead of sweet dreams, interspersed by the occasional nightmare – you just toss and turn, for hours.
Sleepless in…… [PUT YOUR HOME TOWN].
Blame the phone
Current mobile devices, retro-illuminate using LED light. Officially, the light is white, but it is composed of a considerable amount of blue light.
And blue light – lights us up.
On the spectrum
The wavelength, of the light, which we see as blue, 440–450 nm, hits more than just the traditional photo receptors, i.e. the rods and cones, it also hits another group of photosensors, embedded in the eye. They’re called the intrinsically photosensible retinal ganglion cells or ipRGCs, for short.
Their job, is to
scare suppress, the secretion of melatonin.
Your night valet.
Going to bed
Powering down, a system as complex as the human body, is a mammoth undertaking, because to make the transition, you need to switch up, your energy procurement system.
During the day, supplies trickle in, at regular intervals.
At night, all energy needs, must be met from within.
From start to finish, it can take a couple of hours, to make the adjustments, so you’re ready for bed. Melatonin is the soft spoken, somewhat shy hormone, tasked with this undertaking.
Fading light is the trigger
Now, under “normal” circumstances, as the shadows grow longer and the light begins to fade, the level of blue light, drops……
This is the signal, that it is time, for your night valet, to come on duty.
He slowly emerges, from the pineal gland : draws the curtains and pops a mint on your pillow…… so when your head hits the pillow, you’re OFF to dreamland.
Your valet is missing in action
Unfortunately, gazing at your electronic device, in the moments before bed, sends melatonin scurrying into the pineal gland….
Your night valet, is a technophobe !
The bright lights and flashing screens, scare him off – the effect is mediated by the blue light, hitting the ipRGCs.
No worries – just dim the phone
This is what manufacturers of mobile devices, tell you to do, and to help you do this, most include, blue light blocking features, as part of the package. All you have to do, is to remember, to power your mobile device down, when you hop into bed.
PS : If your model is not the latest, there are lots of DIY options, from the app store.
Problem solved ! Not so fast…………
A group of researchers, based in Spain, decided to put the built in “dimmer” switches, of several makes of phone, to the test.
On the spectrum
Since there are differences between the screen technologies and software options, our team, looked at several different phones.
Step one in their analyses, was to measure the spectrum of light, each phone was emitting.
This was done, by popping the phone, in front of a spectrograph.
With and without, the blue light blocking software, activated.
They experimented with the built in software, as well as the Twighlight app. This is one of several apps available from Google play, offering blue light control, with the intention of attenuating melatonin suppression.
Each phone had it’s own idiosyncrasies, but in all cases, the software delivered, on it’s promise, to tone down the blue.
Here are the spectra for two phones
The bump between 400 and 500 nm, corresponds with the blue light wavelength, the first uses the twighlight app, the second, is using built in software.
In each case, the software, was able to tone, flatten the curve…..
NOTE : The team noted, sometimes to the point, where the phone view, was a little bizarre, making it rather unpleasant, to view things, in the “blue light” protected, state.
Here is the same data, showing the extent, to which the different wavelengths of light were decreased by the software.
Yah ! It works……….
But is it enough to actually make a difference ?
A complete wipe out
Next, the team recorded the lunchtime spectrum, for a typical summer’s day, in Madrid – this is the kind of lighting, which would see you bright eyed and bushy tailed, i.e. your night valet, would be IN HIDING.
They used this as GROUND ZERO, to set the melatonin suppression action spectrum or MSAS, for short. And then they ran, the numbers on the phone spectrum, to determine, how effective they’d be, at attenuating the melatonin suppression.
The performance of the phones varied…………….
A software fail
The level of melatonin suppression, will vary according to the duration of time of light exposure and the spectrum of received light. But even, when the dimmer was set on MAX, the phones, still suppressed melatonin, this can be seen in this table.
In practice, this translates to……….
A six minute benefit
When the software reduces the amount of blue light by 30%, it reduces the MSI only by 11%.
In this scenario, if melatonin would be suppressed, after 60 min, when the software, is not deployed. Using the software, would shift the point of suppression, to 1 hour and 6 min.
You get an extra 6 minutes !
The software ……..
Makes the phone less bright, but you’ll still be bright eyed and bushy tailed. The suppression of the blue light, is not enough, to put melatonin at ease.
Despite deploying the dimmer switch, he will still freak out and hides in the cupboard.
Leaving you, sleepless in……………
Your valet is a technophobe
Don’t fight it, embrace it.
Technology has allowed you to take your phone to bed, but just because you can, doesn’t mean you should. Power down in the hour or so before bed.
Light level and duration of exposure determine the impact of self-luminous tablets on melatonin suppression. Applied Ergonomics (2012) Brittany Wood, Mark S. Rea, Barbara Plitnick, Mariana G. Figueiro.
You’re a regular Jo, most nights, you climb into bed and ……………you’re off to dreamland. Sleep issues don’t explain your weight problems. Not so fast…….
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Dreams make us human and contribute to our neurological health. They’re an innate, natural process, but if you’re sleep compromised, you’re dream compromised too.