Table 5.
Functional MRI (fMRI) and Longitudinal Changes in ECT.
| Author (Year) | n Diagnosis Mean Age (SD) Male/Female Ratio of Responders/Total Medication Status |
Stimulus Delivery Stimulus Waveform Stimulus Intensity (When Reported) Number ECT Sessions (SD) |
Time From ECT Series to Post-ECT Imaging Assessment HC Group: Yes/No |
fMRI Task Image Analysi | Longitudinal Neuroimaging Results |
|---|---|---|---|---|---|
| Functional MRI (fMRI) | |||||
| Christ et al44 (2008) | 11 MDD and bipolar 53 years (11) 3/11 responders Medication was discontinued 3 days prior to the ECT series |
7 RUL/4 bitemporal Brief pulse Seizure threshold, 2.5 × threshold 12 treatments (6) |
Time 2 imaging assessment after the 8 ECT treatment; time 3 completed after the ECT series (time not specified) HC: yes |
fMRI tasks: auditory stimulation paradigm Image analysis: voxel-wise (whole brain) analysis; ROI to assess activation intensities |
ECT time 1 vs time 3: In the voxel-wise analysis, decreased activation in frontal, temporal, parietal, occipital, and anterior cingulate cortices ECT time 1 vs HC: In the voxel-wise analysis, patients had more task-related activation throughout the brain; in the ROI analysis, patients had more activation in the tem-poral, occipital and subcortical areas ECT time 3 vs HC: Patients continued to have increased task-related activation |
| Beall et al45 (2012) | 6 MDD 39 years (5) 4 male/2 female 6/6 responders |
6 bitemporal Brief pulse Dose adjusted for age 9 treatments (4) |
7 to 21 days (range) HC: no |
fMRI tasks: working memory and affective tasks (block designs); resting-state fMRI Image analysis: both ROI to ROI and activation (within an ROI) in the working memory and affective tasks; ROI to ROI in the resting-state fMRI |
ECT time 1 vs time 2: Orbital frontal cortex activation change correlated with depression ratings change in the affective task; the results did not survive multiple comparisons correction in the working memory task and resting-state fMRI |
| Perrin et al46 (2012) | 9 MDD 46 years 6 male/3 female 9/9 responders Patients remained on medication |
9 bitemporal Brief pulse Seizure threshold, 2 × threshold 8 treatments |
Not specified HC: no |
fMRI task: resting-state fMRI (virtual ball passing task) Image analysis: changes in weighed global connectiv-ity used to select seed region in left DLFPC for seed-voxel correlations |
ECT time 1 vs time 2: Weighted global connectivity decreased in the left DLPFC; using this region as a seed, seed-voxel cor-relations revealed decreased connectivity in the anterior cingulate, medial frontal cortex, bilateral DLPFC’s, left parietal region |
| Abbott et al47 (2012) | 12 MDD with (n = 3) and without (n = 9) psychotic features 66 years (10) 4 male/8 female 9/12 remitters Patients remained on medication |
10 RUL/2 bitemporal Brief pulse Seizure threshold, RUL 6 × threshold, bitemporal 2 × threshold 11 treatments (3) |
21 days (14) HC: yes |
fMRI task: resting-state fMRI Image analysis: independent component analysis to select components of interest, functional net-work connectivity to measure correlations between component time courses |
ECT time 1 vs time 2: ECT remitters had increased functional network connectivity between the posterior default mode/ DMPFC and the posterior default mode/left DLPFC ECT time 1 vs HC: Patients had decreased functional network connectivity in both of the above component pairs ECT time 2 vs HC: Aberrant between network relationships normalized with treatment |
Abbreviations: DMPFC, dorsomedial prefrontal cortex; DLFPC, dorsolateral prefrontal cortex; ECT, electroconvulsive therapy; GABA, γ-aminobutyric acid; HC, healthy comparison; MDD, major depressive disorder; MRI, magnetic resonance imaging; ROI, region of interest; RUL, right unilateral; SD, standard deviation.