The role of the cervical inputs in the process of vestibular compensation

The course of spontaneous and neck vibration nystagmus in two patients after unilateral labyrinthectomy was investigated to clarify the role of cervical input in vestibular compensation. In one patient whose velocity of spontanious nystagmus decreased after labyrinthectomy, the velocity of neck vibration nystagmus increased after the operation. In another patient whose velocity of spontaneous nystagmus did not decrease, the velocity of neck vibration nystagmus did not increase. These results indicate that the modulation of sensory input from the neck proprioceptors by neck vibration induced marked nystagmus in the first patient who should have gained better vestibular compensation than the second patient after hemilabyrinthectomy. Thus, it can be speculated that cervical input plays an important role in the process of vestibular compensation.