© INGO ARNDT/GETTY IMAGES
In a small, pitch-dark room at Baylor College of Medicine in Houston, Texas, a homing pigeon stands on a metal platform, its wings restrained in a leather harness and its head held in place by a plastic arm. The platform sits in the center of a 2-foot cubic frame containing electricity-conducting coils—one on every face of the cube. The coils are programmed to precisely deliver magnetic fields from any direction in three-dimensional space.
In an adjacent room cluttered with racks of whirring, bleeping equipment, neuroscientists David Dickman and Le-Qing Wu stare at their computer screens. The pigeon is stock still as it is subjected to a magnetic stimulus directed from hundreds of different positions: the surrounding coils generate a field that incrementally moves through 360° ...
