NCT04694131

Task-dependent Effects of TMS on the Neural Biomarkers of Episodic Memory

Completed NA Results posted Last updated 4 July 2025

What this trial tests

NA trial testing TMS in Normal Physiology in 43 participants. Completed in 24 February 2023.

Timeline

9 July 2021

Primary endpoint
24 February 2023

24 February 2023

Quick facts

Lead sponsor	National Institute of Neurological Disorders and Stroke (NINDS)
Phase	NA
Status	Completed
Study type	INTERVENTIONAL
Allocation	na
Design	single group
Masking	none
Primary purpose	basic science
Enrollment	43
Start date	9 July 2021
Primary completion	24 February 2023
Estimated completion	24 February 2023
Sites	1 location across United States

Drugs / interventions tested

• TMS — full drug profile →

Conditions studied

• Normal Physiology — all drugs for Normal Physiology →

Sponsor

National Institute of Neurological Disorders and Stroke (NINDS)

Who can join

Adults 18 to 40, any sex, with Normal Physiology. Patients with the condition only — healthy volunteers not accepted.

Results — posted to ClinicalTrials.gov

Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.

Memory Performance Primary · 1 hour

Participants completed a memory task with simultaneous EEG acquisition and transcranial magnetic stimulation (TMS) delivered to either a memory-relevant parietal lobe target or a vertex control site. Participants were shown a series of objects in one of four quadrants on the screen, with TMS delivered either prior to or concurrent with the trial onset. They were instructed to remember the object and the location. This outcome measure examines the accuracy of memory for the item and the location (context), presented as the percentage of successful trials. Accuracy is shown for each stimulation

Parietal, before TMS

Group	Value	95% CI
Item	0.89	± 0.01
Context	0.64	± 0.03

Parietal, during TMS

Group	Value	95% CI
Item	0.91	± 0.01
Context	0.66	± 0.03

Vertex, before TMS

Group	Value	95% CI
Item	0.92	± 0.01
Context	0.69	± 0.02

Vertex, during TMS

Group	Value	95% CI
Item	0.89	± 0.01
Context	0.66	± 0.03

Late Positive Posterior (ERP) Event Related Potential Primary · During encoding (with TMS) and during retrieval (after TMS)

Participants completed a memory task with simultaneous EEG acquisition and transcranial magnetic stimulation (TMS) delivered to either a memory-relevant parietal lobe target or a vertex control site. Participants were shown a series of objects in one of four quadrants on the screen, with TMS delivered either prior to or concurrent with the trial onset. They were instructed to remember the object and the location. This outcome measure examines the neural response to trials which were later remembered relative to trials which were later forgotten. Values represent the difference in average EEG a

Parietal, before TMS

Group	Value	95% CI
Encoding	1.49	± 0.83
Retrieval	-0.11	± 1.47

Parietal, during TMS

Group	Value	95% CI
Encoding	1.43	± 0.63
Retrieval	1.29	± 1.88

Vertex, before TMS

Group	Value	95% CI
Encoding	0.96	± 0.76
Retrieval	-0.91	± 1.35

Vertex, during TMS

Group	Value	95% CI
Encoding	-1.07	± 1.41
Retrieval	0.79	± 2.16

Theta/Alpha Power Secondary · During encoding (with TMS) and during retrieval (after TMS)

Participants completed a memory task with simultaneous EEG acquisition and transcranial magnetic stimulation (TMS) delivered to either a memory-relevant parietal lobe target or a vertex control site. Participants were shown a series of objects in one of four quadrants on the screen, with TMS delivered either prior to or concurrent with the trial onset. They were instructed to remember the object and the location. This outcome measure examines the neural response to trials which were later remembered relative to trials which were later forgotten. Values represent the difference in average task-

Parietal, before trial TMS

Group	Value	95% CI
Encoding	1.46	± 2.29
Retrieval	-0.18	± 0.56

Parietal during trial TMS

Group	Value	95% CI
Encoding	0.94	± 3.20
Retrieval	0.06	± 0.46

Vertex, before trial TMS

Group	Value	95% CI
Encoding	2.25	± 5.04
Retrieval	0.18	± 0.50

Vertex, during trial TMS

Group	Value	95% CI
Encoding	1.07	± 3.50
Retrieval	-0.06	± 0.56

Sponsor's own description

Background:

Transcranial magnetic stimulation (TMS) of the brain has been used to change the activity and connections in the brain to improve memory. Researchers are interested in how these brain changes cause memory improvements and how activity at the time of stimulation may change the effects of TMS.

Objective:

To learn how brain stimulation can be used to improve memory.

Eligibility:

Healthy adults ages 18-40

Design:

Participants will be screened with a medical record review.

Participants will have 3 study visits.

At visit 1, participants will have a physical exam and will talk about their health. They will have magnetic resonance imaging (MRI). The MRI scanner is a metal cylinder surrounded by a strong magnetic field. During the MRI, participants will lie on a table that can slide in and out of the scanner. A coil will be placed over the head. Participants will be asked to keep their eyes focused on a small cross on a computer screen inside the scanner. The scanner makes loud noises. Participants will get earplugs.

At visits 2 and 3, participants will have TMS and perform tasks. For TMS, a wire coil encased in plastic is held on the scalp. When the coil is triggered, a brief electrical current passes through the coil and creates a magnetic pulse that stimulates the brain. During TMS, an electroencephalogram (EEG) will record brain activity. For the EEG, a cloth cap with electrodes is fitted on the participant s head. Participants will complete a memory task and a spatial processing task. They will also complete surveys about their mental state.

Participation will last 2-3 weeks.

Publications & conference data

No peer-reviewed publications indexed yet for this trial. Completed trials usually publish results within 12-18 months.