Resting-State EEG Changes with ECT- a Modern Approach

Out on PubMed, from researchers in Canada and Australia, is this study:

Modulation of functional network properties in major depressive disorder following electroconvulsive therapy (ECT): a resting-state EEG analysis.

Hill AT, Hadas I, Zomorrodi R, Voineskos D, Farzan F, Fitzgerald PB, Blumberger DM, Daskalakis ZJ.Sci Rep. 2020 Oct 13;10(1):17057. doi: 10.1038/s41598-020-74103-y.PMID: 33051528

The abstract is copied below:

Electroconvulsive therapy (ECT) is a highly effective neuromodulatory intervention for treatment-resistant major depressive disorder (MDD). Presently, however, understanding of its neurophysiological effects remains incomplete. In the present study, we utilised resting-state electroencephalography (RS-EEG) to explore changes in functional connectivity, network topology, and spectral power elicited by an acute open-label course of ECT in a cohort of 23 patients with treatment-resistant MDD. RS-EEG was recorded prior to commencement of ECT and again within 48 h following each patient's final treatment session. Our results show that ECT was able to enhance connectivity within lower (delta and theta) frequency bands across subnetworks largely confined to fronto-central channels, while, conversely, more widespread subnetworks of reduced connectivity emerged within faster (alpha and beta) bands following treatment. Graph-based topological analyses revealed changes in measures of functional segregation (clustering coefficient), integration (characteristic path length), and small-world architecture following ECT. Finally, post-treatment enhancement of delta and theta spectral power was observed, which showed a positive association with the number of ECT sessions received. Overall, our findings indicate that RS-EEG can provide a sensitive measure of dynamic neural activity following ECT and highlight network-based analyses as a promising avenue for furthering mechanistic understanding of the effects of convulsive therapies.

The pdf is here.

This is a "Scientific Report" in Nature Research. It is hugely modern, sophisticated and largely unreadable to the clinician. (This Luddite would say that the reading time is indefinite/infinite, but the skimming time is about 15 minutes).

Seriously though, this is a contemporary update of the old ECT-EEG literature, now incorporating concepts of changes in functional connectivity and impact on neural circuitry, using 64-channel EEG. The study is very small (23 patients) and there is a confounding mix of RUL and BL ECT. The well known old finding of increased delta and theta spectral power after a course of ECT is replicated, but without showing correlation to clinical outcome. The color figures in the article are beautiful, and worth a look...