Intervestibular integration and its clinical consequences

Research during the last twenty years has led to the conclusion that it is time for a more integrated and dynamic view on the physiological and pathophysiological process during clinical vestibular stimulation and perhaps also to reevaluate the interpretation of the findings. Ten patients with absence of function in one labyrinth were exposed to caloric and rotatory stimulation several times during the compensating period of 8 weeks. In the acute state, caloric irrigation of the normal ear with 30 degrees or rotatory stimulation toward the damaged ear resulted in total inhibition of the spontaneous nystagmus. In the chronic state the same investigation reversed the spontaneous nystagmus in the opposite direction. The investigation has shown that it is possible clinically to study the reactions of every single neuron in the vestibular ocular reflex pathway and in this way establish a more topographic diagnosis.