Bridging Single Neuron Dynamics to Global Brain States

We studied single neuron dynamics during anoxic depolarizations, which are often observed in cases of neuronal energy depletion. Anoxic and similar depolarizations play an important role in several pathologies, notably stroke, migraine, and epilepsy. One of the effects of energy depletion was experimentally simulated in slices of rat cortex by blocking the sodium-potassium pumps with ouabain. The membrane voltage of pyramidal cells was measured. Five different kinds of dynamical behavior of the membrane voltage were observed during the resulting depolarizations. Using bifurcation analysis of a single cell model, we show that these voltage dynamics all are responses of the same cell, with normally functioning ion channels, to particular courses of the intra- and extracellular concentrations of sodium and potassium.

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Single Neuron Dynamics: an Introduction

Neural Modeling and Neural Networks ◽

10.1016/b978-0-08-042277-0.50009-5 ◽

1994 ◽

pp. 57-78 ◽

Cited By ~ 3

Author(s):

LARRY F. ABBOTT

Keyword(s):

Single Neuron ◽

Neuron Dynamics

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Segregated brain state during hypnosis

Neuroscience of Consciousness ◽

10.1093/nc/niab002 ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Jarno Tuominen ◽

Sakari Kallio ◽

Valtteri Kaasinen ◽

Henry Railo

Keyword(s):

Transcranial Magnetic Stimulation ◽

Magnetic Stimulation ◽

Brain State ◽

Neural Connectivity ◽

Single Word ◽

Electrophysiological Response ◽

Hypnotic Induction ◽

Brain States ◽

Global Brain ◽

The Brain

Abstract Can the brain be shifted into a different state using a simple social cue, as tests on highly hypnotizable subjects would suggest? Demonstrating an altered global brain state is difficult. Brain activation varies greatly during wakefulness and can be voluntarily influenced. We measured the complexity of electrophysiological response to transcranial magnetic stimulation in one ‘hypnotic virtuoso’. Such a measure produces a response arguably outside the subject’s voluntary control and has been proven adequate for discriminating conscious from unconscious brain states. We show that a single-word hypnotic induction robustly shifted global neural connectivity into a state where activity remained sustained but failed to ignite strong, coherent activity in frontoparietal cortices. Changes in perturbational complexity indicate a similar move towards a more segregated state. We interpret these findings to suggest a shift in the underlying state of the brain, likely moderating subsequent hypnotic responding.

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