All it takes is an antenna on a headband. If you've got a breathless video report on the dangers of wireless internet connections, that will help your case. It doesn't take much, though, to turn an ominous hint into a real headache.
Some people consider themselves sensitive to electromagnetic fields. They report symptoms such as burning skin, tingling, nausea, dizziness, or chest pain, and they blame their malaise on nearby power lines, cell phones, or WiFi networks. A recent Slate article described such people moving to a remote West Virginia town where radio-frequency signals are banned. (The town is within the U.S. National Radio Quiet Zone, an area that's enforced to keep signals from interfering with radio telescopes there—telescopes that work because they receive the radio-frequency signals constantly hitting our planet from space.)
There's no known scientific reason why a wireless signal might cause physical harm. And studies have found that even people who claim to be sensitive to electromagnetic fields can't actually sense them. Their symptoms are more likely due to nocebo, the evil twin of the placebo effect. The power of our expectation can cause real physical illness. In clinical drug trials, for example, subjects who take sugar pills report side effects ranging from an upset stomach to sexual dysfunction.
Psychologists Michael Witthöft and G. James Rubin of King's College London explored whether frightening TV reports can encourage a nocebo effect. They recruited a group of subjects and showed half of them a clip from a BBC documentary about the potential dangers of wireless internet. (The BBC later acknowledged that the 2007 program was "misleading.") The remaining subjects watched a video about the security of data transmissions over mobile phones.
After watching the videos, subjects put on headband-mounted antennas. They were told that the researchers were testing a "new kind of WiFi," and that once the signal started they should carefully monitor any symptoms in their bodies. Then the researchers left the room. For 15 minutes, the subjects watched a WiFi symbol flash on a laptop screen.
In reality, there was no WiFi switched on during the experiment, and the headband antenna was a sham. Yet 82 of the 147 subjects—more than half—reported symptoms. Two even asked for the experiment to be stopped early because the effects were too severe to stand.
Witthöft says he expected to see a greater effect in people who had watched the frightening documentary. This wasn't the case overall. Instead, the movie mainly increased symptoms in subjects who described themselves beforehand as more anxious.
"It suggests that sensational media reports especially in combination with personality factors (in this case anxiety) increase the likelihood for symptom reports," Witthöft says.
Plenty of symptoms were reported without the sensationalist TV show, though. The antenna on the head, the researchers' allusion to a "new kind of WiFi," and the instructions to monitor their bodies closely were enough to trigger symptoms in many people who watched the other video.
Witthöft points out that his study would have been stronger if there were a third group of subjects who didn't wear the "WiFi" headband at all, but were simply told to pay attention to their bodies for 15 minutes. This kind of attentiveness might trigger symptoms on its own.
Still, Witthöft says, "I think the high percentage of symptom reports nicely shows how powerful nocebo effects are."
Though the researchers set out to show how irresponsible reports in the media can trigger a nocebo effect, they ended up showing how easy it is to make a person feel sick with just a a prop and a few choice words. Even a National Radio Quiet Zone can't protect against that.
Witthöft, M., & Rubin, G. (2013). Are media warnings about the adverse health effects of modern life self-fulfilling? An experimental study on idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF) Journal of Psychosomatic Research, 74 (3), 206-212 DOI: 10.1016/j.jpsychores.2012.12.002