I've also been researching the affects of electromagnetic radiation (such as that from cell phones, laptops, microwave ovens and so on) and it is said massive exposure to this radiation can contribute of mental fatigue, increased difficulty of concentration, and loss of sleep. I've noticed this myself in which I live in the city where we are exposed to large amounts of electromagnetic radiation on a daily basis. But when I go to camping up in northern Michigan, where it is mostly wilderness, I sleep like a log. I imagine that chemical polution also plays a significant role in this.