Familial startle disease (hyperexplexia). Electrophysiologic studies.
Six affected members from a family of 15 patients with familial startle disease (hyperexplexia) underwent extensive electrophysiologic evaluation. The most marked abnormality consisted of prominent C response 60 to 75 ms after median and peroneal nerve stimulation. The somatosensory evoked responses were also relatively high in amplitude. These findings suggest that hyperactive long-loop reflexes may constitute the physiologic basis of startle disease.
D004558:Electric Stimulation; D004569:Electroencephalography; D005073:Evoked Potentials, Somatosensory; D006181:H-Reflex; D006801:Humans; D008475:Median Nerve / Q000502:physiology; D009069:Movement Disorders / Q000235:genetics* / Q000503:physiopathology; D009119:Muscle Contraction; D009135:Muscular Diseases / Q000235:genetics* / Q000503:physiopathology; D009431:Neural Conduction; D010543:Peroneal Nerve / Q000502:physiology; D011930:Reaction Time; D013216:Reflex, Startle