The patient: A 29-year-old man in IndiaThe symptoms: The man, a fighter pilot in the Indian Air Force, went to a civilian neurologist after having persistent headaches for 18 months. The headaches would occur approximately two to three times per month, starting in the late afternoon and lasting up to three days. Sleep did not improve his symptoms. The pain was typically greater on the right side of his head, but he would often feel pain on the left side as well. The pilot also reported that just before a headache, he would experience a "sense of lousiness," his doctors wrote in a report of the case. Sometimes, the pain was so intense that the man was unable to take part in scheduled flights....