Laminar distribution of phase-amplitude coupling of spontaneous current sources and sinks

Although resting-state functional connectivity is a commonly used neuroimaging paradigm, the underlying mechanisms remain unknown. Thalamo-cortical and cortico-cortical circuits generate oscillations at different frequencies during spontaneous activity. However, it remains unclear how the various rh...

Full description

Bibliographic Details
Main Authors: Roberto C Sotero, Alekasandra Beata Bortel, Shmuel eNaaman, Victor Mihai Mocanu, Pascal eKropf, Martin eVilleneuve, Amir eShmuel
Format: Article
Language:English
Published: Frontiers Media S.A. 2015-12-01
Series:Frontiers in Neuroscience
Subjects:
LFP
CSD
Online Access:http://journal.frontiersin.org/Journal/10.3389/fnins.2015.00454/full
id doaj-22ef67ec31cc4039a9c8c08f42a7ae55
record_format Article
spelling doaj-22ef67ec31cc4039a9c8c08f42a7ae552020-11-24T23:37:29ZengFrontiers Media S.A.Frontiers in Neuroscience1662-453X2015-12-01910.3389/fnins.2015.00454153731Laminar distribution of phase-amplitude coupling of spontaneous current sources and sinksRoberto C Sotero0Alekasandra Beata Bortel1Shmuel eNaaman2Victor Mihai Mocanu3Pascal eKropf4Martin eVilleneuve5Amir eShmuel6McGill UniversityMcGill UniversityMcGill UniversityMcGill UniversityMcGill UniversityMcGill UniversityMcGill UniversityAlthough resting-state functional connectivity is a commonly used neuroimaging paradigm, the underlying mechanisms remain unknown. Thalamo-cortical and cortico-cortical circuits generate oscillations at different frequencies during spontaneous activity. However, it remains unclear how the various rhythms interact and whether their interactions are lamina-specific. Here we investigated intra- and inter-laminar spontaneous phase-amplitude coupling (PAC). We recorded local-field potentials using laminar probes inserted in the forelimb representation of rat area S1. We then computed time-series of frequency-band- and lamina-specific current source density (CSD), and PACs of CSD for all possible pairs of the classical frequency bands in the range of 1–150 Hz. We observed both intra- and inter-laminar spontaneous PAC. Of 18 possible combinations, 12 showed PAC, with the highest measures of interaction obtained for the pairs of the theta/gamma and delta/gamma bands. Intra- and inter-laminar PACs involving layers 2/3–5a were higher than those involving layer 6. Current sinks (sources) in the delta band were associated with increased (decreased) amplitudes of high-frequency signals in the beta to fast gamma bands throughout layers 2/3–6. Spontaneous sinks (sources) of the theta and alpha bands in layers 2/3 to 4 were on average linked to dipoles completed by sources (sinks) in layer 6, associated with high (low) amplitudes of the beta to fast-gamma bands in the entire cortical column. Our findings show that during spontaneous activity, delta, theta, and alpha oscillations are associated with periodic excitability, which for the theta and alpha bands is lamina--dependent. They further emphasize the differences between the function of layer 6 and that of the superficial layers, and the role of layer 6 in controlling activity in those layers. Our study links theories on the involvement of PAC in resting-state functional connectivity with previous work that revealed lamina-specific anatomical thalamo-cortico-cortical connections.http://journal.frontiersin.org/Journal/10.3389/fnins.2015.00454/fullfunctional connectivityresting statespontaneous activityLFPCross-frequency couplingCSD
collection DOAJ
language English
format Article
sources DOAJ
author Roberto C Sotero
Alekasandra Beata Bortel
Shmuel eNaaman
Victor Mihai Mocanu
Pascal eKropf
Martin eVilleneuve
Amir eShmuel
spellingShingle Roberto C Sotero
Alekasandra Beata Bortel
Shmuel eNaaman
Victor Mihai Mocanu
Pascal eKropf
Martin eVilleneuve
Amir eShmuel
Laminar distribution of phase-amplitude coupling of spontaneous current sources and sinks
Frontiers in Neuroscience
functional connectivity
resting state
spontaneous activity
LFP
Cross-frequency coupling
CSD
author_facet Roberto C Sotero
Alekasandra Beata Bortel
Shmuel eNaaman
Victor Mihai Mocanu
Pascal eKropf
Martin eVilleneuve
Amir eShmuel
author_sort Roberto C Sotero
title Laminar distribution of phase-amplitude coupling of spontaneous current sources and sinks
title_short Laminar distribution of phase-amplitude coupling of spontaneous current sources and sinks
title_full Laminar distribution of phase-amplitude coupling of spontaneous current sources and sinks
title_fullStr Laminar distribution of phase-amplitude coupling of spontaneous current sources and sinks
title_full_unstemmed Laminar distribution of phase-amplitude coupling of spontaneous current sources and sinks
title_sort laminar distribution of phase-amplitude coupling of spontaneous current sources and sinks
publisher Frontiers Media S.A.
series Frontiers in Neuroscience
issn 1662-453X
publishDate 2015-12-01
description Although resting-state functional connectivity is a commonly used neuroimaging paradigm, the underlying mechanisms remain unknown. Thalamo-cortical and cortico-cortical circuits generate oscillations at different frequencies during spontaneous activity. However, it remains unclear how the various rhythms interact and whether their interactions are lamina-specific. Here we investigated intra- and inter-laminar spontaneous phase-amplitude coupling (PAC). We recorded local-field potentials using laminar probes inserted in the forelimb representation of rat area S1. We then computed time-series of frequency-band- and lamina-specific current source density (CSD), and PACs of CSD for all possible pairs of the classical frequency bands in the range of 1–150 Hz. We observed both intra- and inter-laminar spontaneous PAC. Of 18 possible combinations, 12 showed PAC, with the highest measures of interaction obtained for the pairs of the theta/gamma and delta/gamma bands. Intra- and inter-laminar PACs involving layers 2/3–5a were higher than those involving layer 6. Current sinks (sources) in the delta band were associated with increased (decreased) amplitudes of high-frequency signals in the beta to fast gamma bands throughout layers 2/3–6. Spontaneous sinks (sources) of the theta and alpha bands in layers 2/3 to 4 were on average linked to dipoles completed by sources (sinks) in layer 6, associated with high (low) amplitudes of the beta to fast-gamma bands in the entire cortical column. Our findings show that during spontaneous activity, delta, theta, and alpha oscillations are associated with periodic excitability, which for the theta and alpha bands is lamina--dependent. They further emphasize the differences between the function of layer 6 and that of the superficial layers, and the role of layer 6 in controlling activity in those layers. Our study links theories on the involvement of PAC in resting-state functional connectivity with previous work that revealed lamina-specific anatomical thalamo-cortico-cortical connections.
topic functional connectivity
resting state
spontaneous activity
LFP
Cross-frequency coupling
CSD
url http://journal.frontiersin.org/Journal/10.3389/fnins.2015.00454/full
work_keys_str_mv AT robertocsotero laminardistributionofphaseamplitudecouplingofspontaneouscurrentsourcesandsinks
AT alekasandrabeatabortel laminardistributionofphaseamplitudecouplingofspontaneouscurrentsourcesandsinks
AT shmuelenaaman laminardistributionofphaseamplitudecouplingofspontaneouscurrentsourcesandsinks
AT victormihaimocanu laminardistributionofphaseamplitudecouplingofspontaneouscurrentsourcesandsinks
AT pascalekropf laminardistributionofphaseamplitudecouplingofspontaneouscurrentsourcesandsinks
AT martinevilleneuve laminardistributionofphaseamplitudecouplingofspontaneouscurrentsourcesandsinks
AT amireshmuel laminardistributionofphaseamplitudecouplingofspontaneouscurrentsourcesandsinks
_version_ 1725519712981352448