Topic: climbing fibers

Neuronal circuits assemble in a non-random fashion, achieving specificity beyond cell-cell apposition. Two mechanisms have been classically proposed to fine-tune brain circuits: activity or genetics-dependent processes. Experimental evidence supports both options, suggesting a balanced contribution of each. In this study, we explored the interplay between synaptic activity and gene expression during developmental critical periods in olivo-cerebellar circuitry. Early postnatally, cerebellar Purkinje cells (PC) are connected by multiple climbing fibers (CF) emerging from the inferior olive in th

Dendrites play a fundamental role in neuronal computation. It is thought that functionally defined regions of dendritic branches, termed ‘dendritic computational units’ are used to decode information transmitted by synaptic input. This information is encoded by the corresponding dendritic output, to perform complex neuronal computations. To investigate dendric input-output in vivo, it is necessary to record synaptic input and dendritic output simultaneously. To do this we perform simultaneous glutamate imaging and voltage imaging from the spiny dendrites of single Purkinje neurons in awake mic

The cerebellum plays a key role in motor learning, adapting movements in response to perturbations or errors. For simple tasks like eyeblink classical conditioning, climbing fibers originating in the inferior olive and projecting to the cerebellum provide neural instructive signals sufficient to drive learning. For complex whole-body behaviors like locomotion, however, it is not known what role climbing fibers play. We recently demonstrated (Darmohray et al., 2019) that mice running on a split-belt treadmill (that controls the speed under each side of the body independently) exhibit a form of

The Cerebellar Nuclei (CN) are the sole output of the cerebellum, integrating and relaying information computed in the cerebellar cortex and transmitted by Purkinje cells, before sending it to the downstream targets of the cerebellum. The cerebellum receives two types of afferents: mossy fibers (sensory-motor context) and climbing fibers (teaching signals). These inputs project to the cerebellar cortex, with some also sending direct excitatory collaterals to the CN. However, little is known about the functional properties and the impact of these excitatory inputs on the firing of cerebellar nu