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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

Acutely disconnecting of the VTA does not affect neuronal avalanche dynamics in the cortical part of the co-culture.(a) Light microscopic picture of a cortex (Ctx)-Ventral Tegmental Area (VTA) co-culture grown on a planar microelectrode array (MEA). Left: before acute dissection. Right: after acute dissection of the connection between the two tissue regions (broken line). (b) Spontaneous gamma-burst in the LFP from a single electrode in the cortex part of the culture before and after the dissection. (c) Cluster size distribution before and after dissection (average from 3 cultures). Note that in this plot the probability of cluster size s, i.e. P, is multiplied by s^alpha which translates the power law into a horizontal graph up to the cut-off.DOI:http://dx.doi.org/10.7554/eLife.07224.021
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fig9: Acutely disconnecting of the VTA does not affect neuronal avalanche dynamics in the cortical part of the co-culture.(a) Light microscopic picture of a cortex (Ctx)-Ventral Tegmental Area (VTA) co-culture grown on a planar microelectrode array (MEA). Left: before acute dissection. Right: after acute dissection of the connection between the two tissue regions (broken line). (b) Spontaneous gamma-burst in the LFP from a single electrode in the cortex part of the culture before and after the dissection. (c) Cluster size distribution before and after dissection (average from 3 cultures). Note that in this plot the probability of cluster size s, i.e. P, is multiplied by s^alpha which translates the power law into a horizontal graph up to the cut-off.DOI:http://dx.doi.org/10.7554/eLife.07224.021

Mentions: Regarding the firing rate in VTA neurons and their relation to λ, see Author response image 2, which demonstrates experimentally that avalanche dynamics are not affected in cortex-VTA co-cultures when the VTA or midbrain culture is acutely disconnected from the cortex. This work was done in the context of a developmental study using cortex-VTA cultures as an in vitro model (Gireesh and Plenz, 2008).10.7554/eLife.07224.021Author response image 2.Acutely disconnecting of the VTA does not affect neuronal avalanche dynamics in the cortical part of the co-culture.


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)

Acutely disconnecting of the VTA does not affect neuronal avalanche dynamics in the cortical part of the co-culture.(a) Light microscopic picture of a cortex (Ctx)-Ventral Tegmental Area (VTA) co-culture grown on a planar microelectrode array (MEA). Left: before acute dissection. Right: after acute dissection of the connection between the two tissue regions (broken line). (b) Spontaneous gamma-burst in the LFP from a single electrode in the cortex part of the culture before and after the dissection. (c) Cluster size distribution before and after dissection (average from 3 cultures). Note that in this plot the probability of cluster size s, i.e. P, is multiplied by s^alpha which translates the power law into a horizontal graph up to the cut-off.DOI:http://dx.doi.org/10.7554/eLife.07224.021
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4492006&req=5

fig9: Acutely disconnecting of the VTA does not affect neuronal avalanche dynamics in the cortical part of the co-culture.(a) Light microscopic picture of a cortex (Ctx)-Ventral Tegmental Area (VTA) co-culture grown on a planar microelectrode array (MEA). Left: before acute dissection. Right: after acute dissection of the connection between the two tissue regions (broken line). (b) Spontaneous gamma-burst in the LFP from a single electrode in the cortex part of the culture before and after the dissection. (c) Cluster size distribution before and after dissection (average from 3 cultures). Note that in this plot the probability of cluster size s, i.e. P, is multiplied by s^alpha which translates the power law into a horizontal graph up to the cut-off.DOI:http://dx.doi.org/10.7554/eLife.07224.021
Mentions: Regarding the firing rate in VTA neurons and their relation to λ, see Author response image 2, which demonstrates experimentally that avalanche dynamics are not affected in cortex-VTA co-cultures when the VTA or midbrain culture is acutely disconnected from the cortex. This work was done in the context of a developmental study using cortex-VTA cultures as an in vitro model (Gireesh and Plenz, 2008).10.7554/eLife.07224.021Author response image 2.Acutely disconnecting of the VTA does not affect neuronal avalanche dynamics in the cortical part of the co-culture.

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