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theninjkaymarie
10-02-2012, 08:12 AM
So my character is Kidnapped and left with his eyes covered for several months. There is absolutely no light entering them. He's in a room with windows, so he isn't vitamin d deprived. He is already a little bit mentally disturbed, and I've been able to find information about how his sleep might be affected. However, I'm havig difficulty finding what the effects, if any, no light for months, probably around three or four, would have on his eyes. He's 19 and wears contacts normally, but he doesn't have any problems with his eyes other than natural vision loss. So, would he have any trouble with vision when light is reintroduced to him? How long would it take for his eyes to adjust to the light if there isn't really anything significantly wrong other than not bein used to the light?

blacbird
10-02-2012, 08:34 AM
I don't know how directly relevant this is, but a true story: As a military reporter in Vietnam, I encountered a really creepy sniper dude working for a special forces unit. He lived in darkness, enclosed in a blackout hootch during the day, doing his work only at night. He had developed extraordinary night vision. He didn't even use starlight scopes on his rifle.

He was known to his comrades, with whom he had no daytime contact, as "The Prince of Darkness".

A second story involves the miraculous rescue of a group of Chilean miners who, a couple of years ago, had been trapped in a gold mine by a roof collapse. They were first believed dead, but through something close to a miracle, managed to make contact with rescuers, after many days. It took weeks more to rescue them, but all were ultimately retrieved alive. They had been in utter darkness for weeks. They needed their eyes shielded for some time when brought into the light at the surface.

caw

Canotila
10-02-2012, 11:21 AM
UV light doesn't travel through glass so unless he's getting D through supplements of some sort, he's going to be deficient.

If your MC is an adult being low on vitamin D for several months isn't going to give him rickets or anything. It might cause achy joints, decreased fertility, and mood problems (depression). His circumstances would be just as likely to cause most of those symptoms anyway, so I wouldn't really worry about it.

Chris P
10-02-2012, 11:33 AM
I remember hearing that you will go blind if deprived of light for long enough. At least that's what they've told me on every cave and mine tour I've ever been on. Even when you return to the surface your eyes will never recover.

theninjkaymarie
10-02-2012, 03:12 PM
Thank so much for your help! All of you were very helpful, thanks!!

auriel
10-02-2012, 04:15 PM
UV light doesn't travel through glass so unless he's getting D through supplements of some sort, he's going to be deficient.

If your MC is an adult being low on vitamin D for several months isn't going to give him rickets or anything. It might cause achy joints, decreased fertility, and mood problems (depression). His circumstances would be just as likely to cause most of those symptoms anyway, so I wouldn't really worry about it.

UVA light can travel through glass. UVB doesn't. They're different wavelengths.


Another thing you want to think about, besides the lack of light, is the lack of the eyes focusing. People in submarines, where nothing is ever more than a few feet from their eyes for months at a time, have to take time to look through periscopes to retrain their eyes for distance-viewing. (According to Neil deGrasse Tyson, at least.) If a person's eyes don't focus for months, the muscles that allow them to do so will become weak, and they may lose all or partial ability to focus on near/distant objects.

Of course this may all be moot if your character goes permanently blind from lack of light. But just something else to think about ;)

anguswalker
10-02-2012, 08:12 PM
you will go blind if deprived of light for long enough
I can think of no mechanism that would cause this to happen. Auriel's point about weakness in the focussing muscles because of inactivity is a reasonable one, though I would not have thought that would be a long-term effect. There might well be a similar effect on the iris sphincter muscle which controls dilation of the pupil, though again this effect (if any) would likely be very short-lived.

There would be a risk of damage to eyesight if the subject was brought out of long-term darkness into sunlight without eye protection, because the pupil would be fully dilated and might remain so for longer than usual because of weakness in the iris sphincter. This would mean that bright daylight could be strong enough to damage the retina because the pupil did not contract quickly. However with reasonable caution (dark sunglasses would do) this risk could be averted. I would expect him to have perfectly normal eyesight again within hours, if not minutes (though it is possible they might be sensitive to bright light and/or have difficulty focussing on near objects for a couple of days, because of the muscle weakness, if such a thing occurred.)

Maryn
10-02-2012, 08:30 PM
Like that scene in "Brubaker" when new prison warden Robert Redford brings the inmates out of solitary, handing each one dark sunglasses!

Maryn, sorry to derail

Canotila
10-02-2012, 08:47 PM
UVA light can travel through glass. UVB doesn't. They're different wavelengths.


It's UVB that the body uses to produce vitamin D so he'd still be deficient.

theninjkaymarie
10-03-2012, 08:18 AM
Okay. Wow this is all so interesting! So, just to make sure, there wouldn't be a very high risk of long term or permanent damage to his eyes?(of course, emotional scarring might be a little different) He just might have a little difficulty with bright lights and focusing his eyes which would go away fairly soon?

anguswalker
10-03-2012, 11:06 AM
Correct- there would be no permanent or long-term damage to the eyes. Any readjustment to normal daylight would happen pretty soon, so long as his eyes had not been damaged by looking at very bright light immediately after coming out.

An interesting effect of very long term total darkness might have been that he started using other senses to 'see.' The brain is extraordinarily good at readjusting and he would pretty quickly start building a 'picture' of his surroundings using hearing, touch and the sensation of air on skin. He would pretty quickly become dependent on this, and after several months might have become quite confident in navigating his surroundings in total darkness.

What would be intriguing would be how long this acute awareness of other senses persisted after he regained the power of sight. He might for instance for some time afterwards find himself not turning on lights when getting up in the middle of the night as he was so used to operating in total darkness that he temporarily forgot about light. This might well surprise (and potentially shock) a partner. He would probably be more aware of slight sounds and gentle air movements. He might also unconsciously walk around with his hands held out in front of him and sliding his feet along the floor to avoid tripping- techniques he would have developed whilst in darkness.

Quentin Nokov
10-03-2012, 10:54 PM
I always thought leaving contacts in for an extended period of time can damage the cornea. It's why they should be removed at bedtime. If he's wearing them for four months or more straight, they could potentially and severely damage his eyesight methinks.

Shizam! I was right, here's a link: http://en.wikipedia.org/wiki/Effects_of_long-term_contact_lens_wear_on_the_cornea

theninjkaymarie
10-05-2012, 02:57 AM
oh, well when I said he noramlly wears contacts i just meant to show that his vision isn't perfect, but by all means is fairly normal. However, I was considering ways that his eyes might be covered, and I was debating blacked out contacts vs. a blindfold. The contacts might damage his vision permanently, but it would be much easier for him to slide the blindfold off while handcuffed than to get the contacts out. Thanks for providing that though, it makes deciding much easier. Unless anyone has any other ideas for covering his eyes?

StormChord
10-06-2012, 08:38 AM
From what I've heard, physically the eyes will be ridiculously light-sensetive for a long time afterwards.
Mentally is a different, and very interesting, story.
The human mind cannot handle monotony in any of the five senses. That's why a totally silent room is so oppressive - your mind won't let you stop thinking about it. To be left in darkness for that long would mean a large number of intense visual hallucinations - possibly spilling over into the other senses, depending on his environment. He's likely to begin by experiencing shifting colors, then escalating into geometric patterns and possibly all the way up to vivid, half-awake dreams. Depending on the kind of hallucinations you choose to have him experience, his mental state after his release could be very… interesting.

theninjkaymarie
10-07-2012, 08:33 AM
Thanks:) and he's already bipolar among other things, so he's already prone to some hallucinations when he's having an extremely bad episode and off his meds. He's definitely going to have some problems after he gets out of there!

JimmyB27
10-12-2012, 07:30 PM
Like that scene in "Brubaker" when new prison warden Robert Redford brings the inmates out of solitary, handing each one dark sunglasses!

Maryn, sorry to derail
"Why do my eyes hurt?"
"You've never used them before"


Also sorry to derail. :D