Skip to content

Neuromodulation

TL;DR — ECT has the largest acute effect and is central for severe, psychotic, catatonic, or urgent depression, but requires anesthesia and relapse prevention; older meta-analysis found standardized effects of −0.91 versus sham and −0.80 versus pharmacotherapy (UK ECT Review Group 2003, PMID 12642045). Repetitive TMS is less invasive and supported by sham-controlled trials and network meta-analysis (O'Reardon 2007, PMID 17573044; Mutz 2019, PMID 30917990). Accelerated personalized iTBS/SNT produced high remission in small studies, including a double-blind RCT (Cole 2022, PMID 34711062), but replication and durability are still developing. tDCS has a smaller, heterogeneous evidence base; implanted VNS is a long-horizon option for marked resistance; DBS remains investigational.

Modality comparison

Modality Invasiveness Typical course Evidence position Main burden
ECT anesthesia + induced seizure 2–3/week acute series strongest acute efficacy cognitive effects, anesthesia, relapse
rTMS noninvasive magnetic stimulation daily for weeks established time/access, scalp discomfort
iTBS patterned TMS shorter sessions established protocol; accelerated forms emerging durability/target questions
tDCS weak transcranial current repeated sessions modest/heterogeneous uncertain optimal dose
VNS implanted nerve stimulator chronic severe chronic TRD surgery, delayed response
DBS intracranial electrodes chronic investigational neurosurgery, target uncertainty

ECT

ECT is the benchmark for acute efficacy. Meta-analysis found real ECT superior to sham and pharmacotherapy, bilateral placement more effective than unilateral on average, and higher dose more effective at the cost of cognitive effects (UK ECT Review Group 2003, PMID 12642045).

Response does not solve maintenance. After successful ECT, relapse remains common; meta-analysis quantified substantial six-month relapse despite continuation strategies (Jelovac 2013, PMID 23774532). Lithium-containing continuation may reduce relapse, but evidence is limited (Lambrichts 2021, PMID 33506961). Psychotic features and older age predict better acute response at group level (van Diermen 2018, PMID 29436330).

TMS

The pivotal multisite trial established efficacy and safety of left-prefrontal TMS in antidepressant nonresponders (O'Reardon 2007, PMID 17573044). Network meta-analysis supports several non-surgical stimulation protocols, including high-frequency left rTMS, low-frequency right rTMS, bilateral rTMS, theta-burst, and tDCS, with variable certainty (Mutz 2019, PMID 30917990).

Theta-burst delivers patterned pulses more quickly. Meta-analysis supports efficacy and tolerability in major depression (Chu 2021, PMID 33166668). Accelerated schedules compress many sessions into days; SNT added individualized functional-connectivity targeting and produced a positive small double-blind trial (Cole 2022, PMID 34711062) after an open-label study (Cole 2020, PMID 32252538).

Inflammation has now crossed from a proposed bridge to preliminary human prediction evidence. In an exploratory cohort of 54 patients, baseline inflammatory-protein clusters differed in iTBS response and the lower-response cluster was enriched for cytokine, chemokine, and interleukin pathways; the analysis remains hypothesis-generating because the clusters were data-derived and have not been externally validated (Pedraz-Petrozzi 2026, PMID 42364721).

ECT versus ketamine

In ELEKT-D, ketamine was noninferior to ECT for response in nonpsychotic TRD (Anand 2023, PMID 37224232). The result excludes psychotic depression and does not erase differences in durability, cognitive effects, medical eligibility, and service burden.

tDCS, VNS, DBS

A dose-response meta-analysis across disorders supports active effects for TMS and tDCS while highlighting protocol heterogeneity (Sabé 2024, PMID 38776083). A one-year randomized sham-controlled VNS trial provides newer controlled evidence in TRD (Conway 2025, PMID 39706521). DBS target studies remain small and should be framed as experimental.

The live registry includes DBS with sensing (NCT05773755), iTBS intensity response (NCT06392867), multisite rTMS (NCT06363981), personalized versus non-personalized iTBS (NCT07528157), and home wearable rTMS (NCT07775586), re-verified through exact ClinicalTrials.gov v2 records on 2026-08-30.

Safety and selection

Issue Modality
Transient memory impairment ECT
Rare prolonged seizure/mania ECT/TMS
Hearing protection TMS
Implanted-metal/device compatibility TMS/DBS/VNS
Surgical infection/hardware VNS/DBS
Post-response relapse planning all modalities

Comparative neuromodulation deepening

Neuromodulation spans interventions with different invasiveness, evidence maturity, and targets. Device labels should not obscure protocol heterogeneity.

Modality Best-supported use Quantitative/interpretive constraint
ECT Severe, psychotic, catatonic, urgent, or highly resistant depression High acute efficacy; relapse and autobiographical-memory outcomes require explicit follow-up
Standard rTMS Acute MDD after inadequate response Coil, frequency, intensity, target, session count, and sham quality vary
iTBS Shorter-session alternative to conventional rTMS Noninferiority of session format does not validate every accelerated schedule
Accelerated personalized TMS Promising rapid TRD response Targeting, dose, acceleration, and expectancy are bundled
tDCS Modest noninvasive signal in some networks Home use magnifies adherence and blinding concerns
VNS Long-horizon adjunct for chronic TRD Delayed effects and nonrandomized comparators complicate causal inference
DBS Experimental for extreme TRD Small heterogeneous trials and target selection prevent routine use

The main unresolved comparison is not device versus sham in isolation, but which patient should receive ECT, TMS, ketamine, or continued pharmacologic augmentation first, under a shared functional and durability endpoint.

Additional live-search evidence ledger

The records below were added after full PubMed E-utilities retrieval on 2026-08-30. The ledger states the evidentiary role of each record and preserves the design limitation that should travel with its citation.

  • Kolshus E 2017 — Bitemporal v. high-dose right unilateral electroconvulsive therapy for depression: a systematic review and meta-analysis of randomized controlled trials. Meta-analysis; pooled estimates depend on eligibility, heterogeneity, and reporting bias. (Kolshus E 2017, PMID 27780482)

  • Kishi T 2024 — Theta burst stimulation for depression: a systematic review and network and pairwise meta-analysis. Meta-analysis; pooled estimates depend on eligibility, heterogeneity, and reporting bias. (Kishi T 2024, PMID 38844532)

  • Brunoni AR 2017 — Repetitive Transcranial Magnetic Stimulation for the Acute Treatment of Major Depressive Episodes: A Systematic Review With Network Meta-analysis. Meta-analysis; pooled estimates depend on eligibility, heterogeneity, and reporting bias. (Brunoni AR 2017, PMID 28030740)

  • Li H 2021 — Comparative efficacy and acceptability of neuromodulation procedures in the treatment of treatment-resistant depression: a network meta-analysis of randomized controlled trials. Meta-analysis; pooled estimates depend on eligibility, heterogeneity, and reporting bias. (Li H 2021, PMID 33780827)

  • Zhang Y 2026 — Repetitive Transcranial Magnetic Stimulation for Major Depressive Disorder: A Systematic Review and Network Meta-Analysis. Meta-analysis; pooled estimates depend on eligibility, heterogeneity, and reporting bias. (Zhang Y 2026, PMID 42383744)

  • Li J 2022 — Optimal parameter determination of repetitive transcranial magnetic stimulation for treating treatment-resistant depression: A network meta-analysis of randomized controlled trials. Meta-analysis; pooled estimates depend on eligibility, heterogeneity, and reporting bias. (Li J 2022, PMID 36532172)

  • Matsuda Y 2022 — Comparative Efficacy and Acceptability of 3 Repetitive Transcranial Magnetic Stimulation Devices for Depression: A Meta-Analysis of Randomized, Sham-Controlled Trials. Meta-analysis; pooled estimates depend on eligibility, heterogeneity, and reporting bias. (Matsuda Y 2022, PMID 34320488)

  • Ontario Health (Quality) 2021 — Repetitive Transcranial Magnetic Stimulation for People With Treatment-Resistant Depression: A Health Technology Assessment. Systematic review; useful for mapping consistency and gaps, not automatically a pooled causal estimate. (Ontario Health (Quality) 2021, PMID 34055112)

  • Rosson S 2022 — Brain stimulation and other biological non-pharmacological interventions in mental disorders: An umbrella review. Systematic review; useful for mapping consistency and gaps, not automatically a pooled causal estimate. (Rosson S 2022, PMID 35714757)

  • Hieronymus F 2026 — Assessing the presence of biasing and non-biasing unblinding in a randomized controlled trial of a home-use tDCS device: An exploratory analysis. Randomized comparison; population, control credibility, duration, and missingness bound transportability. (Hieronymus F 2026, PMID 41796776)

  • Reddy S 2024 — Efficacy of Deep Brain Stimulation for Treatment-Resistant Depression: Systematic Review and Meta-Analysis. Meta-analysis; pooled estimates depend on eligibility, heterogeneity, and reporting bias. (Reddy S 2024, PMID 39197490)

  • Memon RI 2020 — Effectiveness and Safety of Ketamine for Unipolar Depression: a Systematic Review. Systematic review; useful for mapping consistency and gaps, not automatically a pooled causal estimate. (Memon RI 2020, PMID 32852658)

  • Rhee TG 2025 — Longitudinal associations of electroconvulsive therapy with all-cause mortality and suicide deaths in severe unipolar or bipolar depression: a systematic review and meta-analysis. Meta-analysis; heterogeneity, comparator choice, and reporting bias govern interpretation. (Rhee TG 2025, PMID 41407487)

Durability and follow-up minimums

Modality Follow-up question that acute response cannot answer
ECT relapse after index course, maintenance strategy, and autobiographical-memory trajectory
rTMS/iTBS persistence after treatment-free follow-up and value of maintenance sessions
Accelerated TMS whether rapid remission survives multisite replication and one-year observation (Cole 2022, PMID 34711062)
VNS/DBS delayed benefit, explant/revision burden, and long-horizon comparative outcomes (Conway 2025, PMID 39706521)

Open questions

  • Do SNT remission rates replicate independently at multisite scale (Cole 2022, PMID 34711062)?
  • Which targeting method adds enough benefit to justify MRI and modeling?
  • What continuation schedule best prevents post-ECT relapse (Jelovac 2013, PMID 23774532)?
  • Which patients should receive ketamine rather than ECT (Anand 2023, PMID 37224232)?

References

  1. UK ECT Review Group. Efficacy and safety of ECT in depressive disorders. Lancet. 2003. PMID 12642045
  2. Jelovac A, et al. Relapse following successful ECT for major depression. Neuropsychopharmacology. 2013. PMID 23774532
  3. van Diermen L, et al. Prediction of ECT response and remission. British Journal of Psychiatry. 2018. PMID 29436330
  4. Lambrichts S, et al. Does lithium prevent relapse following successful ECT? Acta Psychiatrica Scandinavica. 2021. PMID 33506961
  5. O'Reardon JP, et al. TMS in acute major depression: multisite RCT. Biological Psychiatry. 2007. PMID 17573044
  6. Mutz J, et al. Non-surgical brain stimulation for major depressive episodes. BMJ. 2019. PMID 30917990
  7. Chu HT, et al. Theta-burst stimulation for major depression. Progress in Neuro-Psychopharmacology & Biological Psychiatry. 2021. PMID 33166668
  8. Cole EJ, et al. Stanford Accelerated Intelligent Neuromodulation Therapy. American Journal of Psychiatry. 2020. PMID 32252538
  9. Cole EJ, et al. Stanford Neuromodulation Therapy: double-blind RCT. American Journal of Psychiatry. 2022. PMID 34711062
  10. Anand A, et al. Ketamine versus ECT. New England Journal of Medicine. 2023. PMID 37224232
  11. Sabé M, et al. TMS and tDCS across mental disorders. JAMA Network Open. 2024. PMID 38776083
  12. Conway CR, et al. VNS in TRD: one-year sham-controlled trial. Brain Stimulation. 2025. PMID 39706521
  13. Kolshus E, et al. Bitemporal v. high-dose right unilateral electroconvulsive therapy for depression: a systematic review and meta-analysis of randomized controlled trials. Psychological medicine. 2017;47:518-530. PMID 27780482
  14. Kishi T, et al. Theta burst stimulation for depression: a systematic review and network and pairwise meta-analysis. Molecular psychiatry. 2024;29:3893-3899. PMID 38844532
  15. Brunoni AR, et al. Repetitive Transcranial Magnetic Stimulation for the Acute Treatment of Major Depressive Episodes: A Systematic Review With Network Meta-analysis. JAMA psychiatry. 2017;74:143-152. PMID 28030740
  16. Li H, et al. Comparative efficacy and acceptability of neuromodulation procedures in the treatment of treatment-resistant depression: a network meta-analysis of randomized controlled trials. Journal of affective disorders. 2021;287:115-124. PMID 33780827
  17. Zhang Y, et al. Repetitive Transcranial Magnetic Stimulation for Major Depressive Disorder: A Systematic Review and Network Meta-Analysis. Journal of evidence-based medicine. 2026:e70155. PMID 42383744
  18. Li J, et al. Optimal parameter determination of repetitive transcranial magnetic stimulation for treating treatment-resistant depression: A network meta-analysis of randomized controlled trials. Frontiers in psychiatry. 2022;13:1038312. PMID 36532172
  19. Matsuda Y, et al. Comparative Efficacy and Acceptability of 3 Repetitive Transcranial Magnetic Stimulation Devices for Depression: A Meta-Analysis of Randomized, Sham-Controlled Trials. Neuropsychobiology. 2022;81:60-68. PMID 34320488
  20. Ontario Health (Quality). Repetitive Transcranial Magnetic Stimulation for People With Treatment-Resistant Depression: A Health Technology Assessment. Ontario health technology assessment series. 2021;21:1-232. PMID 34055112
  21. Rosson S, et al. Brain stimulation and other biological non-pharmacological interventions in mental disorders: An umbrella review. Neuroscience and biobehavioral reviews. 2022;139:104743. PMID 35714757
  22. Hieronymus F, et al. Assessing the presence of biasing and non-biasing unblinding in a randomized controlled trial of a home-use tDCS device: An exploratory analysis. Journal of affective disorders. 2026;405:121553. PMID 41796776
  23. Reddy S, et al. Efficacy of Deep Brain Stimulation for Treatment-Resistant Depression: Systematic Review and Meta-Analysis. Biological psychiatry. Cognitive neuroscience and neuroimaging. 2024;9:1239-1248. PMID 39197490
  24. Memon RI, et al. Effectiveness and Safety of Ketamine for Unipolar Depression: a Systematic Review. The Psychiatric quarterly. 2020;91:1147-1192. PMID 32852658
  25. Rhee TG, et al. Longitudinal associations of electroconvulsive therapy with all-cause mortality and suicide deaths in severe unipolar or bipolar depression: a systematic review and meta-analysis. BMJ mental health. 2025;28:e302083. PMID 41407487
  26. Pedraz-Petrozzi B, et al. Baseline inflammatory profiles in moderate-to-severe depression and differential response to intermittent theta-burst stimulation. Progress in Neuro-Psychopharmacology & Biological Psychiatry. 2026;148:111814. PMID 42364721