Simulation of the effect of the randomness of climbing fiber input on the relationship between motor learning and Focal Task-Specific Dystonia

Abstract

Focal Task-Specific Dystonia (FTSD) is an intractable neurological disorder with no clear prevention or treatment that affects more than 1% of classical musicians and threatens the active lives of experts due to its task-specific tremor symptoms. In the present study, we focused on the motor learning function of the cerebellum, which has not been the focus of much attention in the past. We numerically simulated the firing of cerebellar Purkinje cells and cerebellar nuclei during eyeblink conditioning as a typical example of cerebellar-related timing motor learning, with the aim to find the principle of the pathogenesis of FTSD at the level of individual neurons. The results showed the sustained firing of cerebellar nuclei after the learning condition in which the climbing fiber input to Purkinje cells was continued randomly. Therefore, the present study claims a suggestive factor regarding the neural mechanism of the cerebellum in the motor learning-induced task-specific tremor, which is a symptom of FTSD. We also proposed a motor learning paradigm, "undesirable motor learning," in which the motor goal is too advanced to be achieved by repetitions alone and converges to a different result than the desired.