The influence of cerebellar lesions on the otolith postural reflexes-experimental study

Authors

Dr. med. Wojciech Kazmierczak (Bydgoszcz, Poland)
Dr. med. Katarzyna Pawlak-Osinska (Bydgoszcz, Poland)
Prof. Dr. med. Henryk Kazmierczak (Bydgoszcz, Poland)

Proceedings

XXX Congress of the NES - Oporto - Portugal

Topics

Neurootology
Equilibrium
Diseases
Neurootology
Propioceptive
Diseases
Neurootology
Equilibrium
Equilibriometric tests
Neurootology
Equilibrium
Neurootology
Neurootology
Propioceptive

Keywords

Cerebellar lesions, Cerebellar vermis, Laberint reflex, Otolith system, Postural reflex.

Abstract

Between main postural reflexes, there are tonic labyrinth reflexes generated in otolith system as a results of earth gravity. The neck extensors action is a result of these reflexes and the medullar structures are their centers. It is known that the rigidity of decerebrated animals is caused by the fastigial nucleus damage and that this nucleus is connected with nodulus.
The aim of the study was to estimate the disturbance of the otolith postural reflexes after partial cerebellectomy in pigeon. We measured, in ablation experiments, changes of head position during body rotation around transversal axis. In these manoeuvres, vector of earth gravity form otolith reflexes and it makes possible keeping the head in horizontal plane.
The results of our experiments- hemicerebellectomy and vermis ablation-showed the normal reflexes after hemicerebellectomy and great disturbances of these reflexes after vermis ablation.
Our observations support the outlook that in cerebellar structures vermis (nodulus and fastigial nucleus), not flocculus plays the serious role in controlling the vestibular reflexes.
( The postural reflexes in experiments were registered on CD)