New illusions resulting from failures in proprioception are described. The Forked Tongue illusion results from weaving the tongue among the prongs of a fork, or from using the prongs of a fork to distort skin on other parts of the body-in these cases, the prongs feel misaligned even though the fork has not bent. The Tongue Twister illusion results from turning the tongue upside down and probing it with a finger or foreign object-the object can be felt to be in the wrong spatial location, opposite to where it actually is on the tongue.