An investigation of the nocebo effect—the placebo effect's evil twin.Can beliefs make you sick? Consider "The June Bug" incident from a US textile factory in the early 1960s. Many employees began to feel dizzy, had an upset stomach, and vomited. Some were even hospitalized. The illness was attributed to a mysterious bug biting workers. However, when the CDC investigated this outbreak, no bugs or any other cause of the illnesses could be identified. Instead, it appe...