Neck Vibration-Evoked Nystagmus in Vestibular Migraine: Mechanistic Insights into Role of Proprioception

IntroductionVestibular migraine is a major cause of recurrent vertigo, yet its mechanisms and diagnostic markers remain limited. Abnormal vestibular-cervical integration and convergence insufficiency, reflected by impaired near point convergence (NPC),suggest multisensory dysfunction. This study tested whether cervical proprioceptive perturbation provokes vertigo and nystagmus in vestibular migraine and evaluated NPC as a predictor of these responses. MethodsFifty-one vestibular migraine patients and 12 controls underwent interictal vestibular testing. Peripheral function was assessed with vHIT. Participants received randomized 100-Hz cervical (proprioceptive) and mastoid (vestibular) vibration without visual fixation, with eye movements recorded via video Frenzel goggles and NPC measured using standard methods. Analyses included McNemars, Wilcoxon signed-rank, Mann-Whitney U, correlations, and multivariable logistic regression. ResultsNeck vibration provoked vertigo in all vestibular migraine patients and none of the controls, producing nystagmus in 76.5%. Horizontal, ipsiversive nystagmus predominated, while less frequent vertical responses showed higher velocities. Mastoid vibration elicited no nystagmus. NPC was the only independent predictor of nystagmus and correlated with slow-phase velocity and bilateral responses. Age correlated with drift velocity, whereas vestibulo-ocular reflex gain showed no association. DiscussionNeck vibration elicits vertigo and nystagmus in vestibular migraine, providing the first objective physiological marker. NPC predicts and correlates with nystagmus severity, highlighting its value as a surrogate of multisensory dysfunction. Together, these findings implicate abnormal cervical-vestibular integration and position NPC and neck-vibration testing as practical tools for diagnosis and phenotyping. Key pointsO_LIVestibular migraine affects [~]3% of population yet remains highly controversial. C_LIO_LIObjective measures reveal reproducible vertigo and nystagmus in vestibular migraine. C_LIO_LIImpaired convergence strongly predicts vibration-induced nystagmus in VM patients. C_LIO_LIFindings support sensory mismatch model linking cervical proprioception to vertigo. C_LI