Corrigendum: Long-Lasting Response Changes in Deep Cerebellar Nuclei in vivo Correlate With Low-Frequency Oscillations

Purkinje cells (PCs) integrate all computations performed in the cerebellar cortex to inhibit neurons in the deep cerebellar nuclei (DCN). Simple spikes recorded in vivo from pairs of PCs separated by <100 μm are known to be synchronized with a sharp peak riding on a broad peak, but the significance of this finding is unclear. We show that the sharp peak consists exclusively of simple spikes associated with pauses in firing. The broader, less precise peak was caused by firing-rate co-modulation of faster firing spikes. About 13% of all pauses were synchronized, and these pauses had a median duration of 20 ms. As in vitro studies have reported that synchronous pauses can reliably trigger spikes in DCN neurons, we suggest that the subgroup of spikes causing the sharp peak is important for precise temporal coding in the cerebellum.

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Taurine in deep cerebellar nuclei of the rat. In vivo comparison to GABA inhibitory effect

Brain Research ◽

10.1016/0006-8993(90)90450-p ◽

1990 ◽

Vol 514 (1) ◽

pp. 155-158 ◽

Cited By ~ 11

Author(s):

J.M. Billard

Keyword(s):

Cerebellar Nuclei ◽

Inhibitory Effect ◽

Deep Cerebellar Nuclei

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Bidirectional propagation of low frequency oscillations over the human hippocampal surface

Nature Communications ◽

10.1038/s41467-021-22850-5 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Jonathan K. Kleen ◽

Jason E. Chung ◽

Kristin K. Sellers ◽

Jenny Zhou ◽

Michael Triplett ◽

...

Keyword(s):

Low Frequency ◽

Low Frequency Oscillations ◽

Spatiotemporal Processing ◽

Propagation Axis ◽

Theta Frequency ◽

Temporal Pole ◽

Scale Network ◽

Bidirectional Propagation ◽

Oscillation Frequencies

AbstractThe hippocampus is diversely interconnected with other brain systems along its axis. Cycles of theta-frequency activity are believed to propagate from the septal to temporal pole, yet it is unclear how this one-way route supports the flexible cognitive capacities of this structure. We leveraged novel thin-film microgrid arrays conformed to the human hippocampal surface to track neural activity two-dimensionally in vivo. All oscillation frequencies identified between 1–15 Hz propagated across the tissue. Moreover, they dynamically shifted between two roughly opposite directions oblique to the long axis. This predominant propagation axis was mirrored across participants, hemispheres, and consciousness states. Directionality was modulated in a participant who performed a behavioral task, and it could be predicted by wave amplitude topography over the hippocampal surface. Our results show that propagation directions may thus represent distinct meso-scale network computations, operating along versatile spatiotemporal processing routes across the hippocampal body.

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Sustained Reduction of Cerebellar Activity in Experimental Epilepsy

BioMed Research International ◽

10.1155/2015/718591 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Kim Rijkers ◽

Véronique M. P. Moers-Hornikx ◽

Roelof J. Hemmes ◽

Marlien W. Aalbers ◽

Yasin Temel ◽

...

Keyword(s):

Animal Model ◽

Dentate Nucleus ◽

Seizure Control ◽

Low Frequency ◽

Cerebellar Nuclei ◽

Experimental Epilepsy ◽

Deep Cerebellar Nuclei ◽

Interpositus Nucleus ◽

Sustained Reduction ◽

Immuno Histochemistry

Clinical and experimental evidence suggests a role for the cerebellum in seizure control, while no data are available on cerebellar activity between seizures. We hypothesized that interictal regional activity of the deep cerebellar nuclei is reduced in epilepsy and tested this in an animal model by using ΔFosB and cytochrome oxidase (COX) (immuno)histochemistry. The expression of these two markers of neuronal activity was analysed in the dentate nucleus (DN), interpositus nucleus (IN), and fastigial nucleus (FN) of the cerebellum of fully amygdala kindled rats that were sacrificed 48 hours after their last seizure. The DN and FN of kindled rats exhibited 25 to 29% less ΔFosB immunopositive cells than their respective counterpart in sham controls (P<0.05). COX expression in the DN and FN of kindled animals was reduced by 32 to 33% compared to respective control values (P<0.05). These results indicate that an epileptogenic state is characterized by decreased activity of deep cerebellar nuclei, especially the DN and FN. Possible consequences may include a decreased activation of the thalamus, contributing to further seizure spread. Restoration of FN activity by low frequency electrical stimulation is suggested as a possible treatment option in chronic epilepsy.

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Unusually slow spike frequency adaptation in deep cerebellar nuclei neurons preserves linear transformations on the sub-second time scale

10.1101/2021.08.10.455865 ◽

2021 ◽

Author(s):

Mehak M Khan ◽

Christopher H Chen ◽

wade G regehr

Keyword(s):

Brain Slices ◽

Cerebellar Nuclei ◽

Spike Frequency ◽

Initial Increase ◽

Projection Neurons ◽

Spike Frequency Adaptation ◽

Linear Transformations ◽

Deep Cerebellar Nuclei ◽

Frequency Adaptation

Purkinje cells (PCs) are spontaneously active neurons of the cerebellar cortex that inhibit glutamatergic projection neurons within the deep cerebellar nuclei (DCN) that in turn provide the primary cerebellar output. Brief reductions in PC firing rapidly increase DCN neuron firing. However, prolonged reductions in PC inhibition, as seen in some disease states, certain types of transgenic mice, and in acute slices of the cerebellum, do not evoke large sustained increases in DCN firing. Here we test whether there is a mechanism of spike-frequency adaptation in DCN neurons that could account for these properties. We find that prolonged optogenetic suppression of PC synapses in vivo transiently elevates PC firing that strongly adapts within ten seconds. We perform current-clamp recordings at near physiological temperature in acute brain slices to examine how DCN neurons respond to prolonged depolarizations. Adaptation in DCN neurons is exceptionally slow and bidirectional. A depolarizing current step evokes large initial increases in firing that decay to less than 20% of the initial increase within approximately ten seconds. Such slow adaptation could allow DCN neurons to adapt to prolonged changes in PC firing while maintaining their linear firing frequency-current relationship on subsecond time scales.

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