Which term describes a condition in which the eyes make repetitive and uncontrolled movements?

Which term describes a condition in which the eyes make repetitive and uncontrolled movements?

• A. Pancreatitis
• B. Pleural effusion
• C. Laceration
• D. Nystagmus

Answer: (D)

Nystagmus is the term for repetitive, involuntary eye movements. It happens when the neural circuits that control eye motion, especially in the vestibular system and brainstem, are not coordinating the gaze, causing the eyes to drift in one direction and then snap back in a rhythmic pattern. The movements can be horizontal, vertical, or rotary and may be present from birth or acquired from vestibular disease, brain injury, intoxication, or certain medications. In practice, you’ll see the eyes move rhythmically even as the animal tries to fix on a target, and there may be head tilt or balance issues if the vestibular system is involved. The other conditions mentioned affect different organs entirely—pancreatitis involves the pancreas, pleural effusion involves fluid around the lungs, and laceration is a tear in tissue—so they don’t describe eye movements.

Nystagmus is the term for repetitive, involuntary eye movements. It happens when the neural circuits that control eye motion, especially in the vestibular system and brainstem, are not coordinating the gaze, causing the eyes to drift in one direction and then snap back in a rhythmic pattern. The movements can be horizontal, vertical, or rotary and may be present from birth or acquired from vestibular disease, brain injury, intoxication, or certain medications. In practice, you’ll see the eyes move rhythmically even as the animal tries to fix on a target, and there may be head tilt or balance issues if the vestibular system is involved. The other conditions mentioned affect different organs entirely—pancreatitis involves the pancreas, pleural effusion involves fluid around the lungs, and laceration is a tear in tissue—so they don’t describe eye movements.