Table 3.
Large scale network fMRI-neural activity comparisons.
| Article | Cortex sampleda | Neural activity measureb | Task | Comparison | Findings | Comment |
|---|---|---|---|---|---|---|
| He et al., 2008 | Sensory-motor network | ECoG (5) | Rest | Correlation within, between BOLD and ECoG bands, <0.5–200 Hz, at ROIs in, out of network during awake, rapid eye movement (REM), Slow wave sleep (SWS) | BOLD-ECoG <0.5–4 Hz positively correlated in network, not out. ROIs in correlated, not out BOLD-ECoG correlation in independent of arousal state. 50–100 Hz positively correlated BOLD during awake, REM not SWS | This and the next paper establish 50–110 Hz correlated activity on top of ultra slow correlated oscillations in these networks. Suggest 50–100 Hz related to conscious experiences |
| Ko et al., 2011 | Default network: medial FP, Lateral FPT | ECoG (4) | Rest | Independent components of <0.1 Hz in spectral coherence across 1–120 Hz | BOLD power peak 0.015 Hz in network, not out. Spectral coherence 65–110 Hz, peaks at 0.015 Hz | |
| Bettus et al., 2011 | Correlated networks T,P,O, medial F, hippocampus, thalamus | ECoG depths (5) Patients with temporal lobe epilepsy | Rest | Epileptic vs. non-epileptic regions interictal non-linear cross correlations ECoG-BOLD | BOLD connectivity: non-epileptic > epileptic; ECoG connectivity: epileptic > non-epileptic, all frequencies. Directionality in both: epileptic to non-epielptic | Epileptic-non-epileptic region differences vary BOLD vs. ECoG. Suggest widespread neurovascular coupling alterations in epileptic region |
| Nir et al., 2008 | Auditory bilateral | ME depth (3) ECoG (2) | Rest, pure tone, awake, asleep | L-R correlation at <0.1, 0.1–1, >1 Hz. | Interhemispheric correlations in <0.1 Hz, 40–100 Hz ECoG power and unit firing. Greater with sleep. ECoG finding only in electrodes in auditory sensory network, not out | Extends ultra low frequency correlations in network to unit firing. Note that fMRI, ME and ECoG data from different subjects |
In first three publications, network defined by fMRI correlation in same subjects. In last paper, network location defined anatomically with neural activity and fMRI data obtained in different subjects.
Notes for row 1:
a
F, frontal; T, temporal; P, parietal; O, occipital; L, left; R, right.
b
ECoG, electrocorticogram, unless indicated from subdural grids. EP, evoked potentials from ECoG. ME, microelectrodes, with local field potentials (LFP) and single neuron (units) action potentials. “depth” indicates recordings from depth electrodes. Number of subjects indicated in parentheses.