Rapid, uncontrollable eye movements that swish and thump as the eyes roll and blink. Bones that creak as the body moves. Sudden dizziness, loss of balance. Falling down after a loud noise, such as the sound of your own voice, a cough or even laughter. These are hallmarks of a debilitating and relatively rare syndrome known as superior canal dehiscence that has stumped clinicians for a long time.