Hi all. There was a recent article in the Daily Mail which presented a mish-mash of personal anecdotes and unsourced “studies” to put forth the idea that Wi-Fi (and other low-power sources of electromagnetic radiation) presents a possible health danger.
My immediate reaction to this is an unqualified “bullshit”. However, while skimming Wiki for possible scientific citations of EHS, I came across this entry, describing a possibly-related phenomenon (microwave auditory effect) of which I had never previously heard. So this gave me pause - perhaps EHS is not entrirely bullshit? I still surmise that the majority of reported cases in the UK are either psychosomatic in origin or attributable to other natural causes. However, I am neither a physician nor a physicist, so I ask you, my fellow Dopers, what’s the deal with EHS?
No, it is not real. Somebody who was hypersensitive to EMF would by definition experience symptoms when exposed to EMF and not when not exposed to EMF, and thus be able to distinguish between true exposure and a faked control exposure. They can’t.
This is not the one I’ve seen, but it appears to be quite comprehensive. Forty-six studies and over a thousand people claiming to be sufferers, and there was no robust evidence that exposure to EMF - as opposed to a belief that one is exposed to EMF - is responsible for triggering symptoms.
The more I read about this phenomenon, the more sceptically I get about it being real. The only people claiming it to be a health hazard are live-of-the-earth whacky nut jobs.
Aha! This might just be the place to ask a question about something a friend told me. This guy’s not quite 70, and he tells me that when television was first introduced, some people literally could not see it.
He swears he had a childhood friend who, when this friend looked at a television set that was showing a program, would only see a bunch of lines and squiggles.
How could it be true? Remember that television and motion pictures in the form of movies projected from film work on the same basic principle: Persistence of vision, whereby the brain doesn’t perceive changes instantly, but allows them to blur together to create the illusion of a constant moving picture. (That is, the illusion that the picture is stable, as opposed to flickering, and moving.) So these people would have had similar problems seeing movies the same way everyone else did, and movies had been mainstream entertainment decades before television caught on. Did they ever say they had difficulty seeing movies? Do we have any record of any group of people being unable to perceive films as they were intended?
And… where were these people when journalists were looking for stories about Stupid Human Tricks? Do you think journalists ever stopped doing profiles of people with odd properties? Especially when it touched on a New And Controversial Subject, as television was back in the later 1940s-early 1950s. The attention this EHS crap is getting is evidence of that. The odds of it only being this one person are too low to worry about; humans just aren’t that different from each other.
We can’t go back in time. We can’t resurrect the dead. We can, however, apply basic logic and reason our way through the questions this raises, and there are too many really obvious unanswered objections here for it to be taken very seriously.
There’s a guy in my local community who is very vocal about his pretend sensitivity to EM fields. He’s formed an awareness and support group, of which he appears to be the only member, and has been vocally offering advice on how to opt out of the new wireless electricity meters.
The people who complain of “EHS” don’t limit their complaints to hearing clicking and buzzing noises - they’re alleging widespread negative health effects.
I don’t have problems with electromagnetic frequencies. My internal bullshit meter does start going wild when I see something like “I read this in the Daily Mail”.
Easy. He was not as good at pattern recognition, and a fuzzy but recognizable signal for one person was not enough for him. It probably happened once or twice, or only on a specific station at a specific place.
That got exaggerated to him never being able to see what was on the screen, even if it was a perfectly clear picture.
This is exactly what first popped into my mind reading the story.
If he had a severe astigmatism, I would think it would be reasonable that he’d be unable to see early TV pictures. They had very low resolution, and the picture was built in easily discernable horizontal lines. Here’s an example. I can remember watching the little white light that built changes in the picture moving across and down my grandparent’s TV screen, and theirs was an early color set.
He could also have suffered from retinitis pigmentosa. This basically lowers the resolution of the receiving area in the eyeball (retina is like the film in a camera) and generally starts in the center of the field of vision slowly spreading outwards.
RP in childhood is generally not diagnosed for some time. The brain fills in the picture, and the eye increases movement to fill in the missing parts. Since none of us really knows what others see, the person has no realization that the loss is occurring until the darkened areas begin to increase and blend into each other. Until then it’s just a lower resolution.
So, a low resolution retina facing a low resolution TV screen, with no previous experience to allow the brain a chance to fill in the picture? Yeah, I’d say he’d have difficulty figuring out what the hullaballoo was about.
It’s my gut feeling that the claims are bullshit, but if you will allow me to be Devil’s Advocate for a brief moment, it occurs to me that if there were some fault in a particular person’s brain and/or eyes that removed the persistence of vision function, they might indeed see movies as flashing, still images, and TV as single lines that made little sense.[sup]*[/sup]
I have seen it proposed that aliens, if they ever viewed our movies or TV, would see them differently than we do if their persistence of vision were not the same as ours, and there’s no universal law that says it would be.
For TV, but not movies, persistence of vision is only one factor that makes images look real and seem to move. TVs, especially old B&W screens, have a phosphor that retains, then gradually fades the image after being drawn by the electron beam, so human persistence of vision isn’t the only factor here. Still, an alien without persistence of vision would see a degraded picture compared to humans.
Or, if said aliens (or earthly pets) have color vision in a different part of the spectrum than we are accustomed to.
One of Isaac Asimov’s early stories, The Weapon Too Dreadful To Use featured an alien who could only see color in the green region of the spectrum, but he could distinguish as many distinct shades of green (which all looked like distinct colors to him) as we can see of all the usual visible colors.
Or they could even have vision which covers the same range as us, but with a different basis. Humans see in a three-dimensional color space, and most mammals see in a two-dimensional color space, but there’s no reason that a creature couldn’t have more. Such a creature might, for instance, be able to see and identify both yellow and blue, but disagree that a mixture of the two looks at all the same as green.
