electromagnetic brain mapping physiology of source signals · the resting and active brain:...
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![Page 1: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/1.jpg)
Sylvain Baillet
McConnell Brain Imaging CentreMontreal Neurological InstituteMcGill University
Google it! ’MEG MNI ’
Electromagnetic Brain MappingPhysiology of source signals
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Ongoing background brain activity (MEG)
[1.5-40] Hz
Amplitude scale
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Ongoing background brain activity (MEG)
Amplitude scale
[40-350] Hz
![Page 4: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/4.jpg)
Withsubject
Withoutsubject
Hamalainen et al., Rev. Mod. Phys., 1993
Power line contamination
The resting and active brain: frequency power spectrum
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Withsubject
Withoutsubject
Hamalainen et al., Rev. Mod. Phys., 1993
Power line contamination
The resting and active brain: frequency power spectrum
![Page 6: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/6.jpg)
delta
theta alpha
beta terra
incognita
gamma
The resting and active brain: frequency power spectrum
![Page 7: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/7.jpg)
State-‐dependent expressions of neural oscilla3ons
Large-scale electrophysiology; oscillatory “brain rhythms”
aroused β
relaxed α
drowsy 𝜃
light sleep (spindles)
deep sleep δ
![Page 8: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/8.jpg)
State-‐dependent expressions of neural oscilla3ons
Raichle M. Brain Connectivity (2011)
?
fMRI - BOLD
Large-scale electrophysiology; oscillatory “brain rhythms”
aroused β
relaxed α
drowsy 𝜃
light sleep (spindles)
deep sleep δ
![Page 9: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/9.jpg)
State-‐dependent expressions of neural oscilla3ons
“Resting-state networks”Buckner RL et al. Ann NY Acad. Sci. (2008)Carhart-Harris R L , Friston K J Brain (2010)
Resting-state networks
Raichle M. Brain Connectivity (2011)
?
fMRI - BOLD
Large-scale electrophysiology; oscillatory “brain rhythms”
aroused β
relaxed α
drowsy 𝜃
light sleep (spindles)
deep sleep δ
![Page 10: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/10.jpg)
State-‐dependent expressions of neural oscilla3ons
“Resting-state networks”Buckner RL et al. Ann NY Acad. Sci. (2008)Carhart-Harris R L , Friston K J Brain (2010)
Resting-state networks
Raichle M. Brain Connectivity (2011)
?
fMRI - BOLD
Large-scale electrophysiology; oscillatory “brain rhythms”
aroused β
relaxed α
drowsy 𝜃
light sleep (spindles)
deep sleep δ
![Page 11: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/11.jpg)
Electrophysiological origins of MEG/EEG signals
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The neural cell as elementary building block
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The neural cell as elementary building block
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The neural cell as elementary building block
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The neural cell as elementary building block
pyramidal cell as canonical source
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Basic neural electrophysiology
apical dentrites
basal dentrites
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Basic neural electrophysiology
apical dentrites
basal dentrites
- - - - - - - -- - - - - - - -
![Page 18: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/18.jpg)
Basic neural electrophysiology
apical dentrites
basal dentrites
- - - - - - - -- - - - - - - -
++ + + + + + + + + + + +
![Page 19: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/19.jpg)
Basic neural electrophysiology
apical dentrites
basal dentrites
- - - - - - - -- - - - - - - -
++ + + + + + + + + + + +
primary current
![Page 20: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/20.jpg)
Basic neural electrophysiology
apical dentrites
basal dentrites
- - - - - - - -- - - - - - - -
++ + + + + + + + + + + +
return (volume) currents
primary current
![Page 21: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/21.jpg)
Basic neural electrophysiology
apical dentrites
basal dentrites
- - - - - - - -- - - - - - - -
++ + + + + + + + + + + +
return (volume) currents
primary current
![Page 22: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/22.jpg)
Basic neural electrophysiology
apical dentrites
basal dentrites
- - - - - - - -- - - - - - - -
++ + + + + + + + + + + +
return (volume) currents
primary current
![Page 23: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/23.jpg)
Basic neural electrophysiology
apical dentrites
basal dentrites
- - - - - - - -- - - - - - - -
++ + + + + + + + + + + +
primary current
![Page 24: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/24.jpg)
Basic neural electrophysiology
apical dentrites
basal dentrites
- - - - - - - -- - - - - - - -
++ + + + + + + + + + + +
magnetic induction
primary current
![Page 25: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/25.jpg)
magnetometer
Basic neural electrophysiology
apical dentrites
basal dentrites
- - - - - - - -- - - - - - - -
++ + + + + + + + + + + +
magnetic induction
primary current
![Page 26: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/26.jpg)
magnetometer
Basic neural electrophysiology
apical dentrites
basal dentrites
- - - - - - - -- - - - - - - -
++ + + + + + + + + + + +
magnetic induction
primary current
measured induced currents
![Page 27: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/27.jpg)
= +
The equivalent current dipole =
current source model of PSP’s and AP’s
current dipole model
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= +
The equivalent current dipole =
current source model of PSP’s and AP’s
current dipole model
![Page 29: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/29.jpg)
= +
The equivalent current dipole =
current source model of PSP’s and AP’s
current dipole model
![Page 30: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/30.jpg)
influence of cell morphology on signal strength
radial cell morphology
![Page 31: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/31.jpg)
influence of cell morphology on signal strength
radial cell morphology
net current dipole
![Page 32: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/32.jpg)
influence of cell morphology on signal strength
radial cell morphology
net current dipole
weaker net currents than from elongated cell morphology
![Page 33: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/33.jpg)
Mass effect of neural ensembles
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Mass effect of neural ensembles
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Mass effect of neural ensembles
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Mass effect of neural ensembles
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Mass effect of neural ensembles
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Mass effect of neural ensembles
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Mass effect of neural ensembles
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Mass effect of neural ensembles
overlap of multiple PSPs yields stronger contribution to MEG/EEG signalling
![Page 41: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/41.jpg)
Mass effect of neural ensembles
overlap of multiple PSPs yields stronger contribution to MEG/EEG signalling
stronger individual currents but poorer temporal overlap of APs
![Page 42: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/42.jpg)
Mass effect of neural ensembles
overlap of multiple PSPs yields stronger contribution to MEG/EEG signalling
stronger individual currents but poorer temporal overlap of APs
![Page 43: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/43.jpg)
Mass effect of neural ensembles
overlap of multiple PSPs yields stronger contribution to MEG/EEG signalling.
~50,000 cells, at minimum
stronger individual currents but poorer temporal overlap of APs
![Page 44: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/44.jpg)
Mass effect of neural ensembles
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Mass effect of neural ensembles
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Mass effect of neural ensemblesVoltage-‐sensi3ve ion channels (Llinás, 1988; Hille, 2001)
-‐ Large, detectable PSP sodium spikes
‣ from 10,000 synchronous cells
‣ a possible source of high-‐frequency bursts?
![Page 47: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/47.jpg)
Mass effect of neural ensembles
experimental data (micro)MEG
Murakami et al., J. Physiol (2002)
Voltage-‐sensi3ve ion channels (Llinás, 1988; Hille, 2001)
-‐ Large, detectable PSP sodium spikes
‣ from 10,000 synchronous cells
‣ a possible source of high-‐frequency bursts?
![Page 48: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/48.jpg)
mesoscopic distribu3on of currents
cortex
![Page 49: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/49.jpg)
mesoscopic distribu3on of currents
cortex
![Page 50: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/50.jpg)
mesoscopic distribu3on of currents
cortex
nuclei
![Page 51: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/51.jpg)
mesoscopic distribu3on of currents
cortex
nuclei
![Page 52: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/52.jpg)
dynamicsa rapid overview
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dynamicsa rapid overview
![Page 54: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/54.jpg)
Evidence of low-‐to-‐high frequency coupling of neural oscilla3ons: single cells & assemblies
Contreras & Steriade, J. Neurosci. (1995)
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Temporal ji_er of unitary and ensemble responses
Thalamic stimulation Cortical responseContreras & Steriade, J. Neurophys. (1996)
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Ji_er in brain responses or s3mulus 3ming yields slower event-‐related components and lower SNR
• Sloppy s3mulus 3ming (ji_er) yields smeared MEG responses
• Physiological ji_er produces similar effects
• The longer the response latency, the longer and smoother the response
Somatosensory evoked fields
Latency
Adapted from L. Parkkonen
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Oscilla3onsa scaffold of neural dynamics
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Oscilla3onsa scaffold of neural dynamics
![Page 59: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/59.jpg)
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
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Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
![Page 61: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/61.jpg)
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
MEG, EEG, LFP
![Page 62: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/62.jpg)
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
E EE
I I
MEG, EEG, LFP
![Page 63: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/63.jpg)
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
E EE
I I
MEG, EEG, LFP
δ-α cycles
![Page 64: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/64.jpg)
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
E EE
I I
MEG, EEG, LFP
δ-α cycles
𝜸
![Page 65: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/65.jpg)
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
E EE
I I
MEG, EEG, LFP
δ-α cycles
𝜸 𝜸
![Page 66: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/66.jpg)
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
E EE
I I
MEG, EEG, LFP
δ-α cycles
𝜸 𝜸 𝜸
![Page 67: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/67.jpg)
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
E EE
I I
STIM MEG, EEG, LFP
δ-α cycles
𝜸 𝜸 𝜸
![Page 68: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/68.jpg)
E EE
I I δ-α cycles
𝜸 𝜸 𝜸
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
STIM MEG, EEG, LFP
![Page 69: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/69.jpg)
E EE
I I δ-α cycles
𝜸 𝜸 𝜸
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
SI
FIE
Higher-order region
STIM MEG, EEG, LFP
![Page 70: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/70.jpg)
E EE
I I δ-α cycles
𝜸 𝜸 𝜸
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
SI
FIE
Higher-order region
STIM MEG, EEG, LFP
![Page 71: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/71.jpg)
E EE
I I δ-α cycles
𝜸 𝜸 𝜸
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
SI
FIE
Higher-order region
Cortical hub, thalamic relaySTIM MEG, E
EG, LFP
![Page 72: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/72.jpg)
E EE
I I δ-α cycles
𝜸 𝜸 𝜸
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
SI
FIE
Higher-order region
Cortical hub, thalamic relay
β burstsSTIM MEG, E
EG, LFP
![Page 73: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/73.jpg)
E EE
I I δ-α cycles
𝜸 𝜸 𝜸
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
SI
FIE
Higher-order region
Cortical hub, thalamic relay
β burstsSTIM MEG, E
EG, LFP
![Page 74: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/74.jpg)
E EE
I I δ-α cycles
𝜸 𝜸 𝜸
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
SI
FIE
Higher-order region
Cortical hub, thalamic relay
β burstsSTIM MEG, E
EG, LFP
![Page 75: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/75.jpg)
E EE
I I δ-α cycles
𝜸 𝜸 𝜸
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
SI
FIE
Higher-order region
Cortical hub, thalamic relay
β burstsSTIM MEG, E
EG, LFP
![Page 76: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/76.jpg)
E EE
I I δ-α cycles
𝜸 𝜸 𝜸
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
SI
FIE
Higher-order region
Cortical hub, thalamic relay
β burstsSTIM STIM MEG, E
EG, LFP
![Page 77: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/77.jpg)
E EE
I I δ-α cycles
𝜸 𝜸 𝜸
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
SI
FIE
Higher-order region
Cortical hub, thalamic relay
β burstsSTIM STIMSTIM MEG, E
EG, LFP
![Page 78: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/78.jpg)
E EE
I I δ-α cycles
𝜸 𝜸 𝜸
Theore3cal framework: Oscillatory Implementa3on of Perceptual Inference
A possible mechanism for op3mal sensory processing (efficacy in 3ming, metabolism, downstream processing, etc.)
Donhauser, Florin & Baillet, CNS 2014 Schroeder & Lakatos, TINS 2009 Arnal & Giraud, TICS 2012
Slow Inhibitory
Fast InhibitoryExcitatory
Elementary cell assembly
SI
FIE
Higher-order region
Cortical hub, thalamic relay
β burstsSTIM STIMSTIM MEG, E
EG, LFP
![Page 79: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/79.jpg)
Wrap-‐up: dis3nct roles for dis3nct frequencies
![Page 80: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/80.jpg)
Wrap-‐up: dis3nct roles for dis3nct frequencies
![Page 81: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/81.jpg)
Wrap-‐up: dis3nct roles for dis3nct frequencies
δ-α: cycles of regional excitability
![Page 82: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/82.jpg)
Wrap-‐up: dis3nct roles for dis3nct frequencies
δ-α: cycles of regional excitability
β: bursts as expressions of top-down modulations
![Page 83: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/83.jpg)
Wrap-‐up: dis3nct roles for dis3nct frequencies
δ-α: cycles of regional excitability
β: bursts as expressions of top-down modulations
𝜸: bursts nested in slower rhythms, bottom-up signaling
![Page 84: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/84.jpg)
Wrap-‐up: dis3nct roles for dis3nct frequencies
δ-α: cycles of regional excitability
β: bursts as expressions of top-down modulations
𝜸: bursts nested in slower rhythms, bottom-up signaling
E EE
I I
![Page 85: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/85.jpg)
Wrap-‐up: dis3nct roles for dis3nct frequencies
δ-α: cycles of regional excitability
β: bursts as expressions of top-down modulations
𝜸: bursts nested in slower rhythms, bottom-up signaling
E EE
I I
higher 𝜸: PSP spiking ?
![Page 86: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/86.jpg)
Correla3on between low-‐, high-‐frequency ongoing brain rhythms and BOLD
Schölvinck et al., PNAS (2010)
Delta/Theta/Alpha
Beta
Gamma
High-Gamma
![Page 87: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/87.jpg)
MEG Res3ng-‐State Networks
Auditory+
VisualDMN
Dorsal, sensori-motor
fMRI
Florin & Baillet, Neuroimage, 2015
![Page 88: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/88.jpg)
delta
theta alpha
beta terra
incognita
gamma
Cross-‐frequency coupling (CFC): A generic mechanism regula3ng local and long-‐range brain dynamics?
![Page 89: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/89.jpg)
delta
theta alpha
beta terra
incognita
gamma
Cross-‐frequency coupling (CFC): A generic mechanism regula3ng local and long-‐range brain dynamics?
![Page 90: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/90.jpg)
delta
theta alpha
beta terra
incognita
gamma
Cross-‐frequency coupling (CFC): A generic mechanism regula3ng local and long-‐range brain dynamics?
E EEI I
![Page 91: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/91.jpg)
Review
![Page 92: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/92.jpg)
Review
• Signal origins
![Page 93: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/93.jpg)
Review
• Signal origins
๏ currents induced by spa3o-‐temporal overlap of post-‐synap3c poten3als in cell assemblies (cortex and elsewhere)
![Page 94: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/94.jpg)
Review
• Signal origins
๏ currents induced by spa3o-‐temporal overlap of post-‐synap3c poten3als in cell assemblies (cortex and elsewhere)
๏ possible fast spiking ac3vity
![Page 95: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/95.jpg)
Review
• Signal origins
๏ currents induced by spa3o-‐temporal overlap of post-‐synap3c poten3als in cell assemblies (cortex and elsewhere)
๏ possible fast spiking ac3vity
• Dynamics
![Page 96: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/96.jpg)
Review
• Signal origins
๏ currents induced by spa3o-‐temporal overlap of post-‐synap3c poten3als in cell assemblies (cortex and elsewhere)
๏ possible fast spiking ac3vity
• Dynamics
๏ event-‐related responses as resejng of ongoing ac3vity
![Page 97: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/97.jpg)
Review
• Signal origins
๏ currents induced by spa3o-‐temporal overlap of post-‐synap3c poten3als in cell assemblies (cortex and elsewhere)
๏ possible fast spiking ac3vity
• Dynamics
๏ event-‐related responses as resejng of ongoing ac3vity
๏ dis3nct roles of typical frequency bands: net excita3on, bo_om-‐up vs top-‐down signaling, etc
![Page 98: Electromagnetic Brain Mapping Physiology of source signals · The resting and active brain: frequency power spectrum. With subject Without subject Hamalainen et al., Rev. Mod. Phys.,](https://reader033.vdocument.in/reader033/viewer/2022050421/5f9076b08d48e1076f2f26a6/html5/thumbnails/98.jpg)
Review
• Signal origins
๏ currents induced by spa3o-‐temporal overlap of post-‐synap3c poten3als in cell assemblies (cortex and elsewhere)
๏ possible fast spiking ac3vity
• Dynamics
๏ event-‐related responses as resejng of ongoing ac3vity
๏ dis3nct roles of typical frequency bands: net excita3on, bo_om-‐up vs top-‐down signaling, etc
๏ a field of intense research