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Theta Phase-specific TMS to Modulate Prefrontal Activity

Not Applicable
Recruiting
Conditions
Approach/Avoidance Behavior
Interventions
Device: Transcranial magnetic stimulation (TMS)
Registration Number
NCT05416138
Lead Sponsor
University of Minnesota
Brief Summary

The purpose of this study is to evaluate the causal link between the phase of ongoing theta oscillations in the prefrontal cortex and approach/avoidance (Ap/Av) behavior in adults using theta phase-specific transcranial magnetic stimulation (TMS).

Detailed Description

Approach/avoidance (Ap/Av) behavior is a reliable marker of the emotional processes in the human brain and a robust predictor of mood disorders. Although existing scientific studies found a correlation between the approach/avoidance behavior and ongoing theta activity (3-7 Hz) in the left dorsolateral prefrontal cortex, the causal evidence of the phase-dependent role and strength of association between the prefrontal theta oscillations and approach/avoidance behavior are still unclear. Here, we will monitor brain oscillations in real-time non-invasively using electroencephalography during the approach/avoidance test and modulate theta peaks or troughs with transcranial magnetic stimulation. These data will provide novel understanding of the mechanisms of emotional processing in human brain.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
26
Inclusion Criteria
  1. Age between 18 and 65 years old.
  2. Confident level of English language.
Exclusion Criteria
  1. Chronic condition that requires pharmacological treatment over the course of study participation.
  2. Metallic or electric implant in the head, neck, or chest area or otherwise MRI-noncompatible implants.
  3. History or evidence of seizures, head injuries with loss of consciousness, chronic neurological or mental disorder.
  4. Pregnancy or breast-feeding.
  5. History or evidence of alcohol or drug addiction.

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
TMS over the left prefrontal cortexTranscranial magnetic stimulation (TMS)Transcranial magnetic stimulation (TMS) will be administrated with a figure-8 coil over the left dorsolateral prefrontal cortex (DLPFC) at the intensity of up to 120% of the individualized resting motor threshold (rMT). Stimulation will be performed during and for the duration of the cognitive test. Up to three TMS pulses will be delivered at the beginning of every test trial (each trial duration is 2-6 seconds). The total duration of the cognitive testing and stimulation per session is approximately 40 minutes (in 4 blocks with breaks in-between).
TMS over the head vertexTranscranial magnetic stimulation (TMS)Transcranial magnetic stimulation (TMS) will be administrated with a figure-8 coil over the head vertex at the intensity of up to 120% of the individualized resting motor threshold (rMT). Stimulation will be performed during and for the duration of the cognitive test. Up to three TMS pulses will be delivered at the beginning of every test trial (each trial duration is 2-6 seconds). The total duration of the cognitive testing per session is approximately 40 minutes (in 4 blocks with breaks in-between).
Primary Outcome Measures
NameTimeMethod
Reaction times in the Approach/Avoidance testImmediate effect during stimulation

Reaction times (in milliseconds) in the Approach/Avoidance test during transcranial magnetic stimulation (TMS) at the peak vs. trough phases of ongoing prefrontal theta activity.

Secondary Outcome Measures
NameTimeMethod
Amplitude of TMS evoked potentialsImmediate effect during stimulation

Amplitude of transcranial magnetic stimulation (TMS)-evoked potentials (in microvolts) in ongoing electroencephalography (EEG) in the left prefrontal cortex during the stimulation at the peak vs. trough phases of ongoing prefrontal theta activity.

Trial Locations

Locations (1)

University of Minnesota

🇺🇸

Minneapolis, Minnesota, United States

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