ClinicalTrials.gg
CompletedNCT05194098Updated Sep 8, 2026

Using Electrophysiology to Index Non-invasive Brain Stimulation Effects on Reward System Functioning in Depression

An interventional study of TMS: single session intermittent theta burst stimulation (iTBS) to dorsomedial prefrontal target in individuals with major depressive disorder, via MagVenture MagPro R30 device / Cool-DB80 A/P coil and SHAM (inactive) TMS stimulation in Major Depressive Disorder, sponsored by San Francisco Veterans Affairs Medical Center. Completed at 1 site in United States. Open to participants aged 18 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-09-08.

Sponsored by San Francisco Veterans Affairs Medical Center · Not applicable, Interventional, and Basic science

From the registry’s dates

  • Primary completion was Jun 2025, 1 year 4 months ago, and no results have been posted to the registry.
  • Registered 3 months after the study started (first participant enrolled Oct 2021, registered Jan 2022).
Phase
Not applicable
Study type
Interventional
Enrollment
98
Allocation
Non-randomized
Ages
18 Years to 65 Years
Sex
All
01

Study summary

Depression is a leading cause of morbidity and mortality, conferring substantial healthcare and societal costs. By studying methods to non-invasively target neural circuitry involved in reward responsivity, information generated by this project will improve understanding of the circuit alterations that underlie motivation and pleasure deficits in depression, and could also lead to the development of biologically-based markers of neurostimulation-based treatment response.

Read the detailed description

Rewards play a central role in driving behavior. Reward system dysfunctions are increasingly conceptualized as transdiagnostic phenomena, relevant to many psychopathologies. The opportunity to directly modulate reward processing through targeted intervention could have broad mechanistic and clinical value in psychiatry, both for disorders in which reward-responsive circuits are overactive or underactive. The overarching goal of this proposal focuses on one such opportunity in individuals with depression: the investigators will evaluate whether an electrophysiological measure of reward consummation, the Reward Positivity (RewP), which is consistently blunted in depression, can be moved by targeted neurostimulation of a prefrontal-striatal reward circuit.

The premise of the proposed work is a well-developed empirical literature that substantiates the RewP as a measure of subjective reward valuation, with depression-associated blunting of the RewP likely reflecting attenuated reward consummation. Non-invasive brain stimulation techniques, such as repetitive transcranial magnetic stimulation (rTMS), modulate cortical activity and offer novel avenues to probe reward circuitry. Previous research establishes that excitation of a fronto-cingulate reward circuit with rTMS increases RewP magnitude in nicotine addiction, but the extent to which blunted RewP in depression can be rescued via rTMS is unknown.

The investigators therefore propose pilot research to begin to address this literature gap via a repeated-measures study that uses a multi-measure approach to probe reward system functioning under passive and performance-dependent reward conditions. The investigators will examine sham-controlled effects of single session intermittent theta burst stimulation (iTBS) to a dorsomedial prefrontal/anterior cingulate cortex (dmPFC/dACC) target in individuals with major depressive disorder (MDD). The investigators will examine iTBS effects on anticipatory and later consummatory reward measures in addition to our primary focus on the RewP, thus capitalizing on the temporal precision EEG affords by decomposing reward processing into subcomponent processes and examining their differential sensitivity to neurostimulation.

Specific Aim 1 examines case-control RewP differences before stimulation, and changes in RewP magnitude as a function of iTBS in MDD.

Specific Aim 2 examines case-control and within-group MDD iTBS effects on a later-stage consummatory reward measure, the late positive potential (LPP).

Specific Aim 3 examines case-control and within-group MDD iTBS effects on reward anticipation.

Our approach is innovative because i) there is little precedent for using the well-validated RewP or similar measures as indices of rTMS modulation, despite putative hypofunction of reward circuitry in MDD and ii) the investigators target a region strongly implicated in depressive pathophysiology but distinct from the Food and Drug Administration-approved dorsolateral prefrontal rTMS target for depression and ii). Here, the investigators evaluate measures tapping reward anticipation and consummation to assay positive valence system functioning in response to iTBS, setting the stage for future biomarker validation and full-course rTMS clinical trials.

02

Conditions studied

  • Major Depressive Disorder

Keywords

  • Major Depressive Disorder
  • Reward Processing
  • EEG
  • rTMS Neurostimulation
  • dorsal medial prefrontal cortex
03

In context

Depressive Disorder, Major

3,041 studies on the registry are indexed under Depressive Disorder, Major; 588 are open to participants now.

This study's enrollment of 98 is above the median of 79 across 2,530 interventional studies indexed under Depressive Disorder, Major.

Browse Depressive Disorder, Major studies →

Lead sponsor

San Francisco Veterans Affairs Medical Center is the lead sponsor of 21 studies on the registry; 1 is open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 65 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Eligibility criteria

  • Our studies require some in-person visits to our research lab, located at 42nd Ave and Clement St in San Francisco.

Inclusion Criteria:

  • All participants

    • 18-65 years old
    • Normal (or corrected to normal) vision
  • Participants with MDD

    • Meet the (DSM-5) criteria for MDD
    • Screened for TMS and MRI safety
    • On a stable psychiatric medication regime for > 1 month

Exclusion Criteria (all participants):

  • Premorbid IQ estimate \< 70
  • Past or present neurological problems (including seizures and head trauma resulting in neurological or cognitive sequelae)
  • Loss of consciousness > 30 minutes or any loss of consciousness with neurological sequelae
  • Major medical conditions (e.g., seizure disorders, treatment with anticonvulsant medication, endocrine disorders, significant cardiac pathology), or other physical conditions if they preclude participation in EEG, TMS, or MRI protocols (e.g. peripheral nerve damage, limb paralysis etc.)
  • Substance dependence, within the past year, current (past 3 months) substance misuse, or failed urine toxicology on the day of neuroimaging sessions
  • Known claustrophobia
  • Pregnancy (a pregnancy urine test will be conducted to rule-out pregnancy)

Exclusion criteria (Participants with MDD only)

  • Past or present DSM-5 (SCID-5) 'Schizophrenia Spectrum or Other Psychotic Disorder' diagnosis
  • Past or present DSM-5 (SCID-5) Bipolar and Related Disorders Diagnosis
  • Past or present DSM-5 (SCID-5) MDD with psychotic features (mood congruent or mood incongruent)
  • Past or present DSM-5 (SCID-5) Gambling Disorder

Exclusion Criteria (HCs only)

  • DSM-5 (SCID-5) criteria for any psychiatric disorder
Terms in these criteria, in plain language(1)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

DSM diagnostic criteria

The American Psychiatric Association’s manual of mental health diagnoses. DSM-5 (2013, revised as DSM-5-TR in 2022) replaced DSM-IV, and some studies still name the older edition. “Meets DSM criteria for …” means diagnosed by that edition’s diagnostic criteria, usually by a clinician in an interview.

05

Study design

Phase
Not applicable
Primary purpose
Basic science
Allocation
Non-randomized
Intervention model
Crossover assignment
Masking
Double (Participant, Investigator)
Enrollment
98 participants (actual)

Study arms

  • Experimental
    Major Depression Disorder Group: iTBS-EEG

    Device: MagVenture MagPro R30 device with a Cool-DB80 A/P coil (Farum, Denmark) Stimulation: intermittent theta stimulation (iTBS): the investigators will stimulate a dorsomedial prefrontal cortex target at the scalp location (0x 60y 60z). Standard iTBS of 50Hz triplet bursts, 5 times each second with a 2 s on / 8 s off duty cycle for 600 pulses per hemisphere (1200 pulses total) will be applied for a total stimulation time of 6:40 minutes, per session; total session length, including setup is 10-15 min.

    Device: TMS: single session intermittent theta burst stimulation (iTBS) to dorsomedial prefrontal target in individuals with major depressive disorder, via MagVenture MagPro R30 device / Cool-DB80 A/P coil

  • Sham comparator
    Major Depression Disorder Group: SHAM-EEG

    Device: MagVenture MagPro R30 device with a Cool-DB80 A/P coil (Farum, Denmark) Stimulation: sham stimulation (SHAM): Sham stimulation will entail the same procedures for the active stimulation day, but with the sham side of the DB-80 A/P placed exactly on the same anatomical target in the same position and duration, but without any active stimulation. \*Note, iTBS and SHAM stimulation sessions will occur on separate days scheduled one week apart (counterbalanced, across subjects). The two stimulation visits follow identical procedures (with the sole difference being active vs. sham rTMS stimulation), with each followed directly by post-stimulation EEG assessment with SLOT and MID tasks.

    Device: SHAM (inactive) TMS stimulation

  • No intervention
    Baseline Evaluation (Major Depressive Disorder and Healthy Control Groups)

    HC and MDD participants will have visits for clinical assessment and a baseline EEG session to complete reward processing tasks (SLOT AND MID). The SLOT task is a 288-trial EEG task developed in our laboratory. Design features mimic structural characteristics common to real-word slot machines, including sound effects and visualizations, and the display consists of 3 sequentially populated slot reels. Participants initiate each trial via button press, after which timing of the slot reels is automated, such that reward outcome is independent of task performance. The MID task is a 130-trial EEG task designed to model anticipatory and consummatory sub-stages of reward processing in the context of participants being rewarded based on their response times to a cued target detection task.

Interventions

  • DeviceTMS: single session intermittent theta burst stimulation (iTBS) to dorsomedial prefrontal target in individuals with major depressive disorder, via MagVenture MagPro R30 device / Cool-DB80 A/P coil

    Active Session: Single session of standard iTBS of 50Hz triplet bursts, 5 times each second with a 2 s on / 8 s off duty cycle for 600 pulses per hemisphere (1200 pulses total) will be applied for a total stimulation time of 6:40 minutes

  • DeviceSHAM (inactive) TMS stimulation

    Sham neurostimulation (SHAM) entails use of the sham side of the D-B80 A/P placed over the same anatomical target, without any active stimulation.

06

What researchers measure

Primary outcomes

  1. Targeted neurostimulation effects on reward feedback evaluation

    Within the MDD group, the investigators will examine whether neurostimulation of a dmPFC target induces changes in the Reward Positivity (RewP) event-related potential component by comparing RewP amplitude after iTBS to RewP amplitude after sham stimulation.

    Time frame: EEG measurements are collected directly after neurostimulation (iTBS vs SHAM) sessions

Secondary outcomes

  1. Targeted neurostimulation effects on reward anticipation and late-stage evaluation

    Within the MDD group, the investigators will examine whether neurostimulation of a dmPFC target induces changes in anticipatory event-related potential components (SPN; stimulus-preceding negativity, CNV; contingent negative variation) and late-stage evaluation (LPP; late-positive potential) by comparing component amplitudes after iTBS to amplitudes after sham stimulation.

    Time frame: EEG measurements are collected directly after neurostimulation (iTBS vs SHAM) sessions

07

Study locations

1 site
  • San Francisco VA Medical Center
    San Francisco, California 94121, United States
08

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Ran from Oct 2021 to primary completion in Jun 2025, 44 months.

Of 647 non-industry interventional studies with no phase under Depressive Disorder, Major, half reached primary completion within 35 months of starting (the median), counting those still running; a quarter within 19 and three quarters within 55. This study's 44 months is above that.

Counting every sponsor, half of 687 studies reached it within 33 months; a quarter within 17 and three quarters within 55.

How these figures are worked out, and which studies are left out of them.

Registered
Jan 3, 2022
First posted
Jan 18, 2022
StartActual
Oct 1, 2021
Primary completionActual
Jun 24, 2025
CompletionActual
Jun 30, 2025
Last update
Sep 8, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Sep 8, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT05194098
Lead sponsor
San Francisco Veterans Affairs Medical Center
Responsible party
Susanna Fryer, PhD (Staff Clinical Psychologist (VA) and Assistant Professor (UCSF), San Francisco Veterans Affairs Medical Center) — Principal investigator
First posted
Jan 18, 2022
Start date
Oct 1, 2021
Primary completion
Jun 24, 2025
Completion
Jun 30, 2025
Last update
Sep 8, 2026

Study contacts

Susanna L Fryer, PhD
principal investigator · University of California, San Francisco

Oversight

Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
Yes
View the source record on ClinicalTrials.gov ↗

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