Intermittent Vertical Nystagmus in a Father and Son

We report below the occurrence of congenital intermittent vertical nystagmus in a father and son who were in all other respects normal. So far as we can determine, such a case has never been previously reported. Report of Case Case 1. —A 28-year-old male graduate student at the University of California had suffered from attacks of vertical nystagmus since the age of 7 months. These attacks which were usually precipitated by fatigue or emotional upset, occurred at least once a day, were sudden in onset, lasted 20 to 30 minutes, and subsided spontaneously. No aura preceded these spells, but the patient recognized their onset by experiencing blurred vision and rapid vertical oscillation of the environment (oscillopsia). During an attack he could minimize the blurring by looking down and tilting his head back. He had never experienced any alteration in consciousness before, during, or after these attacks. No nausea, vomiting, tongue-biting,