Proceedings of The Physiological Society

Physiology 2016 (Dublin, Ireland) (2016) Proc Physiol Soc 37, PL04

Poster Communications

Inhibition and excitation in the cerebellar nuclei

I. M. Raman1

1. Neurobiology, Northwestern University, Evanston, Illinois, United States.

The cerebellum carries out two distinct roles in motor control in real time: it facilitates learned, coordinated movements and corrects errors. Signals to execute these functions must be carried by the large neurons of the cerebellar nuclei, which form the major premotor projection from the cerebellum. How these neurons fire is determined by the interaction between their intrinsic ion channels, which strongly promote action potential generation, and the constant barrage of synaptic inhibition reaching them from dozens of convergent, rapidly firing Purkinje cells, which tends to suppress firing. During cerebellar behaviors, both depolarization and inhibition are elevated by mossy fiber inputs which excite large premotor cells directly as well as Purkinje cells indirectly, raising the question of how large premotor neurons of the cerebellar nuclei integrate synaptic inhibition and excitation with their intrinsic properties to generate the appropriate signals to regulate movement. Here, we will discuss intrinsic and synaptic mechanisms in the mouse cerebellar nuclei that permit distinct modes of firing in response to different patterns of synaptic inputs as measured in vitro, as well as their relation to movements measured in awake behaving mice. The data provide evidence that not only the rate but also the temporal structure of Purkinje cell firing can influence the efficacy of synaptic excitation of large neurons, the pattern of cerebellar output, and the consequences for motor behavior.

Where applicable, experiments conform with Society ethical requirements