Stylised teaching animation, exaggerated for visibility — not a recording of a real patient, and not a diagnosis.
Localises toCentral
Bedside testPrimary gaze
Fast phaseUp-beating
Reading
Pure up-beating nystagmus in primary gaze, no torsion, spontaneous rather than positionally provoked. Like downbeat, this localises to the brainstem or cerebellum (pontomesencephalic or medullary) and is central on its own in acute vertigo — never treat it as BPPV.
Stylised teaching animations authored by NeuroDash. Not real-patient recordings, not board-certified, and not reviewed by an outside specialist. Educational only — not medical advice and not a diagnosis.