Beta‐gamma burst stimulations of the inferior olive induce high‐frequency oscillations in the deep cerebellar nuclei. (9th March 2018)

• Record Type: Journal Article
• Authors: Cheron, Julian; Cheron, Guy
• Other Names: Mazaheri Ali guestEditor.; Slagter Heleen guestEditor.; Thut Gregor guestEditor.; Foxe John J. guestEditor.
• Is Part Of: European journal of neuroscience. Volume 48:Number 8(2018)
• Page Start: 2879
• Page End: 2889
• Publication Date: 2018-03-09
• Subjects: 350 Hz -- awake mouse -- cerebellum -- deep cerebellar nucleus -- high‐frequency oscillations -- inferior olive electrical stimulation; Nervous system -- Periodicals; 612.8
• DOI: 10.1111/ejn.13873
• Languages: English
• ISSNs: 0953-816X

Abstract

Abstract: The cerebellum displays various sorts of rhythmic activities covering both low‐ and high‐frequency oscillations. These cerebellar high‐frequency oscillations were observed in the cerebellar cortex. Here, we hypothesised that not only is the cerebellar cortex a generator of high‐frequency oscillations but also that the deep cerebellar nuclei may also play a similar role. Thus, we analysed local field potentials and single‐unit activities in the deep cerebellar nuclei before, during and after electric stimulation in the inferior olive of awake mice. A high‐frequency oscillation of 350 Hz triggered by the stimulation of the inferior olive, within the beta‐gamma range, was observed in the deep cerebellar nuclei. The amplitude and frequency of the oscillation were independent of the frequency of stimulation. This oscillation emerged during the period of stimulation and persisted after the end of the stimulation. The oscillation coincided with the inhibition of deep cerebellar neurons. As the inhibition of the deep cerebellar nuclei is related to inhibitory inputs from Purkinje cells, we speculate that the oscillation represents the unmasking of the synchronous activation of another subtype of deep cerebellar neuronal subtype, devoid of GABA receptors and under the direct control of the climbing fibres from the inferior olive. Still, the mechanism sustaining this oscillation remains to be deciphered. Our study sheds new light on the role of the olivo‐cerebellar loop as the final output control of the intercerebellar circuitry. Abstract : Schematic drawing of the main pathways that may hypothetically sustain a 350 Hz oscillation. This high‐frequency oscillation is triggered by an electrical stimulation of the inferior olive (IO) (ranging from 12 to 100 Hz). The multicolour neuron drawn in the deep cerebellar nucleus (DCN) represents the heterogeneity of the neurons known in the DNC. The climbing fibres (CF) and their collaterals (CFC) are represented in red. For simplicity, only the Purkinje cell (PC) and its inhibitory projections to the DCN are illustrated in the cerebellar cortex. The synapses schematized in black and white represent inhibitory and excitatory elements, respectively.