Individualized Closed Loop TMS for Working Memory Enhancement
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|ClinicalTrials.gov Identifier: NCT04402294|
Recruitment Status : Suspended (COVID-19 Restrictions)
First Posted : May 26, 2020
Last Update Posted : May 26, 2020
|Condition or disease||Intervention/treatment||Phase|
|Working Memory in Healthy Participants||Device: Repetitive Transcranial Magnetic Stimulation (rTMS)||Not Applicable|
|Study Type :||Interventional (Clinical Trial)|
|Estimated Enrollment :||38 participants|
|Intervention Model:||Crossover Assignment|
|Intervention Model Description:||
Task and resting fMRI will be used to determine an individualized brain target for each participant. In a subsequent session, participants will complete a task fMRI with repetitive TMS neuromodulation; during this session, various stimulation protocols will be interleaved with working memory task blocks to result in online brain readouts of the degree in which modulation affected the brain state in regards to working memory performance.
Based on this testing, an optimal and sub-optimal TMS stimulation frequency will be determined for each individual participant. Each frequency will be administered separately across three stimulation days using a crossover design, with the order of frequencies being randomized and counterbalanced. Therefore, each subject will receive six days of TMS stimulation: three using the optimal frequency, and three using the sub-optimal frequency. The initial TMS/ task fMRI testing session will be completed at the midpoint and end of the study.
|Masking:||Double (Participant, Care Provider)|
|Primary Purpose:||Basic Science|
|Official Title:||Individualized Closed Loop Transcranial Magnetic Stimulation (TMS) for Working Memory Enhancement|
|Estimated Study Start Date :||August 2020|
|Estimated Primary Completion Date :||January 2024|
|Estimated Study Completion Date :||January 2025|
- Device: Repetitive Transcranial Magnetic Stimulation (rTMS)
The investigators will create individualized TMS targets using deep learning methods on task and resting fMRI data to target working memory augmentation. The individualized target will be stimulated in a subsequent fMRI scan involving working memory task performance interleaved with repetitive TMS (rTMS) delivered at a variety of stimulation frequencies. Based on activation readouts in response to rTMS, an optimal and sub-optimal brain state frequency to impact working memory performance will be selected for each participant. Participants will receive rTMS at each frequency separately for three days (six days total), with the order of frequency randomly assigned and counterbalanced. Following each three day protocol, another fMRI working memory readout will be conducted to support the targeting and frequency selection algorithms.
- fMRI Classifier Fit [ Time Frame: Baseline ]Using deep learning classification methods, an 'optimal' brain state will be identified from baseline task and resting fMRI. This will be the target during future interleaved TMS/fMRI brain readouts.
- Effect of Individualized Stimulation Frequency on Working Memory [ Time Frame: Baseline, Immediately After the Intervention ]Overall, the investigators will be assessing whether there is a significant change in working memory performance using neuromodulation at the individual's optimal stimulation frequency versus sub-optimal frequency, as determined by performance during fMRI/ rTMS sessions and rTMS behavioral sessions.
- Working Memory Performance in MRI Sessions [ Time Frame: Baseline, After approx. 1 month, After approx. 2 months ]During rounds of interleaved rTMS with fMRI recordings, participants will be engaging in a working memory task. Online block-wise performance will be evaluated for both speed and accuracy as an indicator of the effect of the neuromodulation train preceding it.
- Working Memory Performance in Behavior Sessions [ Time Frame: Baseline, Immediately after the Intervention ]During each offline working memory rTMS session, participants' speed and accuracy on a working memory task will be evaluated as an indicator of the degree to which the neuromodulation is affecting performance.
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04402294
|United States, Pennsylvania|
|University of Pennsylvania|
|Philadelphia, Pennsylvania, United States, 19104|