This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anatomy of Inner Ear, Subject name: ENT
True about central nystagmus: 
Select and explain. 
A. Duration > 1 min, B. Direction fixed, C. Latency present, D. Suppressed by visual fixation
A: Duration > 1 min
Answer: A: Duration > 1 min 
Explanation: Impoant differentiating features between peripheral and central nystagmus include the following: Characteristic of spontaneous nystagmus Peripheral vestibular Central vestibular Direction Direction-fixed i.e. unidirectional nystagmus. Direction changing i.e. bidirectional. On visual/optic fixation The nystagmus disappears with visual fixation. The nystagmus, does not disappear with visual fixation Latency 2 - 20 seconds No latency Duration Less than 1 minute More than 1 minute Fatigability Fatigable Non-fatigable