After being called "spoiled, crazy—even devil-possessed," doctors have figured out the cause of a 6-year-old girl's uncontrollable laughing fits. Though the Bolivian girl's often inappropriate bouts of laughter were presented as a behavioral problem, doctors eventually ordered a brain scan and discovered a small, benign tumor called a hamartoma pressed against her temporal lobe. That tumor was causing gelastic seizures, which often look like laughing fits. Now that the tumor has been surgically removed, doctors say she is healthy and no longer suffers from seizures.
A rare form of epilepsy, gelastic seizures are caused by tumors that are often otherwise harmless, though in some instances they can cause growth abnormalities, one doctor tells LiveScience. And while laughter tends to be the primary symptom, the seizures can also produce fits of crying. "It's not necessarily 'hahaha' laughing," the doctor said. "There's no happiness in this. Some of the kids may be very scared." The girl's team of doctors published a case report about her successful surgery in the journal ecancermedicalscience in the hopes of raising awareness in parts of the world where these seizures may be going undiagnosed. (Click to read how epilepsy may have fueled Chopin's visions.)