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Recording Gamma Band Oscillations in Pedunculopontine Nucleus Neurons
Published on: September 14, 2016
Substantia nigra reticulata neurons during sleep-waking states: relation with ponto-geniculo-occipital waves
S Datta1, R Curró Dossi, D Paré
1Département de Physiologie, Faculté de Médecine, Université Laval, Quebec, Canada.
Abstract:
We have previously hypothesized that the spike bursts of brainstem peribrachial (PB) neurons, leading to ponto-geniculo-occipital (PGO) waves in thalamocortical systems, are triggered by phasic hyperpolarizations of sufficient magnitude or by excitatory inputs reaching a steadily hyperpolarized membrane. We have proposed that the source of these hyperpolarizing actions are substantia nigra pars reticulata (SNr) cells that project to, and exert inhibitory effects upon, PB neurons. Here we tested this hypothesis by recording antidromically identified SNr-PB cells in chronically implanted, naturally sleeping cats. A subpopulation of SNr-PB cells exhibited tonically increased firing preceding by 70-200 ms the thalamic PGO wave. These data support the hypothesis that an enhancement in SNr-cells' discharges may lead to hyperpolarization of PB neurons, with the consequence of spike bursts in one class of PGO-related PB-thalamic neurons.
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