Measuring rTMS-induced Neuroplasticity With EEG Steady-state Visual-evoked Potentials

Repetitive Transcranial Magnetic Stimulation Clinical Trial

Official title:

Inducing and Measuring Visual-evoked Potential Plasticity in Humans With Repetitive Transcranial Magnetic Stimulation

Clinical Trial Details — Status: Enrolling by invitation

Administrative data

• NCT number: NCT05853939
• Other study ID #: 62922
• Status: Enrolling by invitation
• Phase: N/A
• Start date: July 1, 2023
• Est. completion date: May 2027

Study information

• Verified date: April 2024
• Source: Stanford University
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The goals of this study are to 1) use EEG steady-state visual evoked potentials as a noninvasive measure of the neuroplasticity induced by repetitive transcranial magnetic stimulation (rTMS), 2) use visual contrast detection paradigms as a behavioral measure of rTMS effects, and 3) to investigate how visual spatial attention augments or suppresses the neuroplastic impact of rTMS. Participants will observe visual stimuli on a screen while allocating their attention to different parts of the visual field and making responses when they observe changes in the visual stimuli. rTMS is performed to visual cortex using MRI-retinotopy neuronavigation. Then the visual task paradigm is performed again.

Recruitment information / eligibility

• Status: Enrolling by invitation
• Enrollment: 60
• Est. completion date: May 2027
• Est. primary completion date: May 2027
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 65 Years

Eligibility

Inclusion Criteria:

• Men and women, ages 18 to 65
• Must comprehend English well to ensure adequate comprehension of the EEG and TMS instructions, and of clinical scales
• Left- or Right-handed
• No current or history of neurological disorders
• No seizure disorder or risk of seizures

Exclusion Criteria:

• Those with a contraindication for MRIs (e.g. implanted metal)
• Any unstable medical condition
• History of head trauma with loss of consciousness
• History of seizures
• Neurological or uncontrolled medical disease
• Active substance abuse
• Diagnosis of psychotic or bipolar disorder
• Currently taking medications that substantially reduce seizure threshold (e.g., bupropion, olanzapine, chlorpromazine, lithium)
• Currently pregnant or breastfeeding

Related Conditions & MeSH terms

• Repetitive Transcranial Magnetic Stimulation

Intervention

Device:
• repetitive transcranial magnetic stimulation
Repetitive TMS targeted by neuronavigation to left lower visual field of primary visual cortex. Randomized to 10 Hz or 1 Hz on different treatment days. Stimulation at 110% of phosphene threshold, or 110% resting motor threshold if phosphenes not detectable. 1 Hz: 1000 pulses total over 1000 seconds. 10 Hz: 1000 pulses over 10 10 second pulse trains, with 50 second intertrain intervals

Locations

Country	Name	City	State
United States	Stanford University	Stanford	California

Sponsors (2)

Lead Sponsor	Collaborator
Stanford University	National Eye Institute (NEI)

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	post-rTMS change in ssVEP Response Amplitude	Change in ssVEP contrast-response amplitude after rTMS	60 minutes
Primary	post-rTMS change in visual contrast perceptual sensitivity	change in visual psychometric threshold across contrasts after rTMS	60 minutes