Affiliations: [a] Department of Physiological and Pharmacological Science, University of Pavia, Pavia, Italy | [b] Department of Computer Engineering and Systems Science, University of Pavia, Pavia, Italy | [c] Department of Otorhinolaryngology, Hospital S. Rita, Milan, Italy | [d] Otoneurological Centre, Pavia, Italy
Correspondence:
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Corresponding author: Prof. Paolo Valli, Department of Physiological and Pharmacological Science, Via Forlanini 6, I-27100 Pavia, Italy. Tel.: +39 0382 507606; Fax: +39 0382 507527; E-mail: paovalli@unipv.it
Abstract: The mechanisms underlying caloric nystagmus are still matter of debate. The original theory proposed by Barany [2] and more recently by Pau and Limberg [14] suggested that convective endolymphatic currents were involved. In contrast Gentine et al. [5,6,7,8,9] suggested that the main mechanism responsible for caloric nystagmus is buoyancy due to calorization of the endolymph, without the need of continuous convective currents. Finally, other authors (Scherer and Clarke [16], Arai et al. [1]) proposed that thermal expansion or contraction of the endolymph were involved. In the present study experimental conditions have been considered able to discriminate between these different models. The experiments, were carried out on isolated labyrinth preparations of the frog. Only the predictions of the model based on buoyancy were fully consistent with the experimental results whereas those provided by the other models were not.
