Influences of vestibulo-cerebellum on kindling in the cat

The development of amygdaloid kindling was assessed under conditions of pharmacological depression of the nodular areas of vestibulocerebellum and also following vestibular stimulation in chronically prepared cats. The results demonstrated that a single intra-nodular micro-injection of procaine hydrochlorides could significantly facilitate such epileptogenesis for at least several days. The number of kindling trials required to reach the first generalized convulsions was significantly increased by natural vestibular stimulation in comparison with control kindled animals. The intensity of fit, development of amygdaloid seizures and the convulsions were reduced markedly within a week by pre-conditioning the kindled animals with daily vestibular stimulation for 15-30 min. In addition, analysis of the behaviour of sleep-wake cycle indicated a significant increase in total sleep time and in the percentage of rapid eye movement (REM) sleep. These findings suggest that the natural rotational vestibular stimulation may result in a durable modification of brain function through development of enduring focal sensitization of catecholamine-mediated inhibitory mechanisms, reflecting the tonic inhibitory influences of the vestibulo-cerebellum in regulating the development and attenuation of epileptic states.