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Irregular spiking of pyramidal neurons organizes as scale-invariant neuronal avalanches in the awake state.

Bellay T, Klaus A, Seshadri S, Plenz D - Elife (2015)

Bottom Line: As the animal transitions from the anesthetized to awake state, spontaneous single neuron firing increases in irregularity and assembles into scale-invariant avalanches at the group level.In vitro spike avalanches emerged naturally yet required balanced excitation and inhibition.This demonstrates that neuronal avalanches are linked to the global physiological state of wakefulness and that cortical resting activity organizes as avalanches from firing of local PN groups to global population activity.

View Article: PubMed Central - PubMed

Affiliation: Section on Critical Brain Dynamics, National Institute of Mental Health, Bethesda, United States.

ABSTRACT
Spontaneous fluctuations in neuronal activity emerge at many spatial and temporal scales in cortex. Population measures found these fluctuations to organize as scale-invariant neuronal avalanches, suggesting cortical dynamics to be critical. Macroscopic dynamics, though, depend on physiological states and are ambiguous as to their cellular composition, spatiotemporal origin, and contributions from synaptic input or action potential (AP) output. Here, we study spontaneous firing in pyramidal neurons (PNs) from rat superficial cortical layers in vivo and in vitro using 2-photon imaging. As the animal transitions from the anesthetized to awake state, spontaneous single neuron firing increases in irregularity and assembles into scale-invariant avalanches at the group level. In vitro spike avalanches emerged naturally yet required balanced excitation and inhibition. This demonstrates that neuronal avalanches are linked to the global physiological state of wakefulness and that cortical resting activity organizes as avalanches from firing of local PN groups to global population activity.

No MeSH data available.


Related in: MedlinePlus

Post-event time histogram of cluster occurrence after occurrence of a large cluster.In general, large clusters are followed by cluster activity for about 10 s (average over all recordings for each state). Temporal resolution: 1x = 250 ms; 4x ∼88 ms. No significant differences were observed for clusters activity following large clusters between the awake or the anesthetized state.DOI:http://dx.doi.org/10.7554/eLife.07224.020
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fig8: Post-event time histogram of cluster occurrence after occurrence of a large cluster.In general, large clusters are followed by cluster activity for about 10 s (average over all recordings for each state). Temporal resolution: 1x = 250 ms; 4x ∼88 ms. No significant differences were observed for clusters activity following large clusters between the awake or the anesthetized state.DOI:http://dx.doi.org/10.7554/eLife.07224.020

Mentions: We have now performed the analysis suggested by the referee, in which spontaneous, large avalanches are used as trigger to compute post-event histograms (a similar approach was taken in (Plenz and Chialvo, 2009; Plenz, 2012)). The corresponding figure is (Author response image 1) for the awake state at two different temporal resolutions (240 ms, black, 88 ms blue) and the anesthetized state (250 ms). These distributions show that for all three conditions, activity rapidly declines beyond ∼1s. Further analysis using larger neuronal populations and longer recordings might be required to identify general features for these histograms. Given the uncertainty in interpretation, we prefer not to include these results in the current manuscript.10.7554/eLife.07224.020Author response image 1.Post-event time histogram of cluster occurrence after occurrence of a large cluster.


Irregular spiking of pyramidal neurons organizes as scale-invariant neuronal avalanches in the awake state.

Bellay T, Klaus A, Seshadri S, Plenz D - Elife (2015)

Post-event time histogram of cluster occurrence after occurrence of a large cluster.In general, large clusters are followed by cluster activity for about 10 s (average over all recordings for each state). Temporal resolution: 1x = 250 ms; 4x ∼88 ms. No significant differences were observed for clusters activity following large clusters between the awake or the anesthetized state.DOI:http://dx.doi.org/10.7554/eLife.07224.020
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4492006&req=5

fig8: Post-event time histogram of cluster occurrence after occurrence of a large cluster.In general, large clusters are followed by cluster activity for about 10 s (average over all recordings for each state). Temporal resolution: 1x = 250 ms; 4x ∼88 ms. No significant differences were observed for clusters activity following large clusters between the awake or the anesthetized state.DOI:http://dx.doi.org/10.7554/eLife.07224.020
Mentions: We have now performed the analysis suggested by the referee, in which spontaneous, large avalanches are used as trigger to compute post-event histograms (a similar approach was taken in (Plenz and Chialvo, 2009; Plenz, 2012)). The corresponding figure is (Author response image 1) for the awake state at two different temporal resolutions (240 ms, black, 88 ms blue) and the anesthetized state (250 ms). These distributions show that for all three conditions, activity rapidly declines beyond ∼1s. Further analysis using larger neuronal populations and longer recordings might be required to identify general features for these histograms. Given the uncertainty in interpretation, we prefer not to include these results in the current manuscript.10.7554/eLife.07224.020Author response image 1.Post-event time histogram of cluster occurrence after occurrence of a large cluster.

Bottom Line: As the animal transitions from the anesthetized to awake state, spontaneous single neuron firing increases in irregularity and assembles into scale-invariant avalanches at the group level.In vitro spike avalanches emerged naturally yet required balanced excitation and inhibition.This demonstrates that neuronal avalanches are linked to the global physiological state of wakefulness and that cortical resting activity organizes as avalanches from firing of local PN groups to global population activity.

View Article: PubMed Central - PubMed

Affiliation: Section on Critical Brain Dynamics, National Institute of Mental Health, Bethesda, United States.

ABSTRACT
Spontaneous fluctuations in neuronal activity emerge at many spatial and temporal scales in cortex. Population measures found these fluctuations to organize as scale-invariant neuronal avalanches, suggesting cortical dynamics to be critical. Macroscopic dynamics, though, depend on physiological states and are ambiguous as to their cellular composition, spatiotemporal origin, and contributions from synaptic input or action potential (AP) output. Here, we study spontaneous firing in pyramidal neurons (PNs) from rat superficial cortical layers in vivo and in vitro using 2-photon imaging. As the animal transitions from the anesthetized to awake state, spontaneous single neuron firing increases in irregularity and assembles into scale-invariant avalanches at the group level. In vitro spike avalanches emerged naturally yet required balanced excitation and inhibition. This demonstrates that neuronal avalanches are linked to the global physiological state of wakefulness and that cortical resting activity organizes as avalanches from firing of local PN groups to global population activity.

No MeSH data available.


Related in: MedlinePlus