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Excess Time Indoors May Explain Rising Myopia Rates
Nature reports that an unexpected factor may be behind a growing epidemic of nearsightedness: time spent indoors. From the article: Because the eye grows throughout childhood, myopia generally develops in school-age children and adolescents. About one-fifth of university-aged people in East Asia now have this extreme form of myopia, and half of them are expected to develop irreversible vision loss.
This threat has prompted a rise in research to try to understand the causes of the disorder — and scientists are beginning to find answers. They are challenging old ideas that myopia is the domain of the bookish child and are instead coalescing around a new notion: that spending too long indoors is placing children at risk. “We're really trying to give this message now that children need to spend more time outside,” says Kathryn Rose, head of orthoptics at the University of Technology, Sydney.
But NOT going outside increases your risks of bone deformity from vitamin D deficiency, and now also increased incidence of myopia.
However, the REAL problem is that helicopter mummsy and daddsy are TERRIFIED that pedobear will rape little timmy and throw him away in an old icechest, because Fox News said so.
So, as with many of the bodies abilities; it's just a case of use that distance vision, or lose it when your eyes adapt to shorter ranges.
Just like muscle strength, flexibility, cognitive function, etc.
You're still focusing on the mirror in both cases.
No. If you are looking at objects seen in the mirror you are focussing at the total distance of : you-mirror plus mirror-object
The mirror wraps the distance but does not reduce how far the light must travel or the object appears.
At last : all those hours I spent in school physics drawing light ray diagrams has come in useful.
oh my godsies, parents have to take care of their kids. Wow, that's terrible. Next thing you know they'll have to find them too... tough shit, have a kid, you better be there to take care of them and raise them.
"Being there" and "taking care" of a kid also involves gradually giving them the freedom to make their own choices and do their own things as they grow. If you don't do this, you end up with kids who never learn to take care of themselves and are still living at home in their late 20s or 30s.
Anyhow, this needs to be based on age and maturity level, obviously. But nowadays we can't trust a 10-year-old to play outside with a 6.5-year-old younger sibling or to walk home from a park together (and yes, the parents ultimately were found responsible for neglect), nor can we trust an 11-year-old alone in a car for a few minutes while Mommy goes into the store.
Etc., etc. Sadly, these stories are not uncommon. There are things like this that come up on a regular basis across the U.S., and if you search a bit you can also read some of the harrowing stories of parents who are force to spend months or years struggling to get their kids back or living under draconian state "supervision" by CPS when they do.
Yes, as parents, you need to supervise your kids when they are little, and then you gradually allow them more freedom. It's called "growing up." But nowadays, people call the cops if they see a kid younger than 16 without a parent around, and CPS comes knocking.
You don't think that's extreme?
I'm 'guilty' of leaving the kids (9 and 11) to read in the car if I know I'll only be in a store for less than ten minutes. But even lately I've limited that to things like a quick pop-in at the drug store, since it seem more likely people would overreact to seeing a child in a car at the grocery store, where the average time the child would be left along is much higher. That I even have to worry about that is just crazy.
The problem with bring authorities into a situation is that they are a very blunt instrument. They are not going to care that I actually am being mindful about evaluating (the usually miniscule to begin with) risks involved. For example:
Ironically, this sort of unnecessary heightened vigilance leads parents to make potentially riskier decisions, if that decision is less likely to come under public scrutiny. For example, if I'm the only parent covering after school, sometimes one or the other has to be picked up, or I have to run out for some other reason. If it's less than 30 minutes, and the child's time would be better spent finishing homework than being stuck in the car, then I'll consider leaving them home. Fortunately they have good judgement, as the hazards in the home far outweigh that of being in a car.
And even then, I'll almost never do that if it means leaving them both alone, as the sibling rivalry factor raises the other risks by several orders of magnitude.
So some stranger's knee-jerk reaction to something that has actually had some thought applied to it poses a greater risk to the welfare of the child than whatever it is they think they are saving them from.
I started noticing this when I was revising for A-Levels. (17-18)
My distance vision would start to fuzz after hours on the books, and be restored by a long walk.
It's pretty much done the same thing ever since.
One thing I do is make sure to focus on distant objects while looking out of the window a few times an hour.
The other thing that helps is wearing +1D reading glasses (just cheap ones from the supermarket). These are designed for oldies who can't focus on close objects anymore - so they move the focal point of close up material much further away. A foot or two away, my monitor is basicaly at infinity, which stops/reverses the atrophy of my distance vision.
Focussing is mediate by muscles! Like any others, use them, or lose them.
Yes, as parents, you need to supervise your kids when they are little, and then you gradually allow them more freedom. It's called "growing up." But nowadays, people call the cops if they see a kid younger than 16 without a parent around, and CPS comes knocking.
You don't think that's extreme?
And it's getting more extreme.
http://www.westernjournalism.c...
The concept of Extended childhood has become pathological.
So you might need to add another 10 years onto the age where they can be taken away from you. To me, it is subtle abuse. Children as people will remain children as long as they are treated like children. And this is robbing them of years of adulthood. And I have to say, at least in my case, I enjoy adulthood a lot more than childhood.
I had completed my first education, had a good job and my first retirement plan by age 25. I fail to see how my remaining a child until that time would have helped either myself, my parents, or society in any way. Hell a lot of people are starting to get gray hair at 25.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
It's you who is the dumbass. Perhaps you should actually think about it, or research it, before calling people out.
This is school level physics.
The mirror doesn't emit light, it reflects it. Which means the light has the same path as before, just bounced into a different angle, convergence and everything.
Try this simple experiment - hold a mirror close by so as to reflect a tree in the distance. Hold a page of text (or a glistening penis, I suppose) next to the mirror. Focus on the text. Now focus on the tree.
Can't do both at the same time, can you?
Or at least go outside and masturbate.
Have gnu, will travel.