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

Launched by STANFORD UNIVERSITY · May 2, 2023

Keywords

ClinConnect Summary

This study is exploring how a noninvasive brain stimulation technique called repetitive transcranial magnetic stimulation (rTMS) affects the brain’s ability to adapt (neuroplasticity) in the visual cortex. Researchers will use EEG measurements of steady-state visual evoked potentials (ssVEP) and visual tasks to see if the stimulation changes brain responses and visual perception. The trial compares several conditions: two active rTMS frequencies (1 Hz and 10 Hz), a sham (placebo) stimulation, and whether the stimulated area is in the part of the visual field you’re paying attention to or not. It’s a randomized, single‑blind, cross‑over study, so you won’t know which hemisphere is targeted or the exact stimulation settings, and you’ll experience multiple conditions across different study days.

Eligible participants are adults aged 18 to 65 who are healthy, right- or left-handed, and able to understand English. Key exclusions include any history of neurological disorders or seizures, MRI safety issues (like metal implants), pregnancy, unstable medical conditions, and medications that lower seizure threshold. If you join, you’ll undergo MRI-guided targeting to the visual cortex and receive stimulation at a safe, comfortable level. After stimulation, you’ll do a visual task again while EEG is recorded, with measurements taken about 60 minutes after stimulation. The study is currently enrolling at Stanford, aims to enroll about 60 people, and is expected to continue through 2027.

Gender

ALL

Eligibility criteria

• 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