The situation: Can the technology that powers our Internet connection — and our lives — be the reason behind our blahs? Now that parks and entire towns have gone wireless, the complaints — headache, itch, insomnia, fatigue, difficulty concentrating — once written off as hypochondria are now on the brains of health officials worrying about long-term cumulative effects. Indeed, Wi-Fi routers emit radio frequency waves, just as cell phones do. And while we don’t press them against our head, their emissions are constant and ubiquitous. Physiologists report that electromagnetic fields (EMFs) produce a biochemical stress response in cells, and some say this can, in the short term, cause those hodgepodge of symptoms known as EMF sensitivity, and, in the long term, make us vulnerable to inflammatory diseases and cancer. But a September Journal of Hygiene and Environmental Health paper reports a "nocebo" effect: Subjects told of higher exposure levels reported worse symptoms, even when levels actually didn’t change. It could be that people's skin cells have different levels of resistance to conductivity; stress may exacerbate sensitivity, too. The strategy: Limit exposure, says Columbia University physiologist Martin Blank, Ph.D. Unplug your home router and avoid public places with Wi-Fi when you’re not using it.