An electronic device can successfully determine whether severe, continuous dizziness is a stroke or nothing to worry about. The device measures eye movements. It feeds webcam video from goggles to computer software that looks for abnormal corrective eye movements when a person's head is turned. The finding is the result of a study led by researchers at Johns Hopkins University School of Medicine. They say the device could be used much like an electrocardiogram is for heart attack. The study is published in the journal "stroke."