Modulation of Brain Oscillations Underlying Working Memory
State-dependent Modulation of Interactions of Theta and Gamma Rhythms in Working Memory
1 other identifier
interventional
32
1 country
1
Brief Summary
This study will use novel transcranial alternating current stimulation (tACS) protocols and electroencephalography (EEG) to modulate and measure brain oscillations that underlie working memory. tACS is a noninvasive method used to modulate the timing and patterns of brain rhythms via weak electric currents passed through electrodes on the scalp.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P25-P50 for not_applicable
Started Jul 2024
Typical duration for not_applicable
1 active site
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
June 20, 2023
CompletedFirst Posted
Study publicly available on registry
June 28, 2023
CompletedStudy Start
First participant enrolled
July 10, 2024
CompletedPrimary Completion
Last participant's last visit for primary outcome
August 31, 2026
ExpectedStudy Completion
Last participant's last visit for all outcomes
March 31, 2027
February 9, 2026
February 1, 2026
2.1 years
June 20, 2023
February 6, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (4)
Working memory accuracy
Accuracy of working memory retrieval during a Delayed Match-to-Sample task will be assessed before and during tACS interventions
2 hours
Working memory accuracy under interference
Accuracy of working memory retrieval during interference conditions of a Delayed Match-to-Sample task will be assessed before and during tACS interventions.
2 hours
Theta-gamma cross-frequency coupling
Cross-frequency coupling between theta band phase and gamma band amplitude will be calculated using the EEG data collected while subjects perform the Delayed Match-to-Sample task before and after tACS interventions.
2 hours
Fronto-parietal theta phase synchronization
Phase synchronization in the theta band between frontal and parietal brain regions will be calculated using the EEG data collected while subjects perform the Delayed Match-to-Sample task before and after the tACS interventions.
2 hours
Study Arms (4)
Theta-nested gamma tACS applied during passive task epochs
EXPERIMENTALParticipants will receive single-session administration of tACS during performance of a working memory task. tACS will be applied during fixation periods between consecutive task trials. EEG will be acquired before and immediately after the intervention.
Theta-nested gamma tACS applied during memory delays
EXPERIMENTALParticipants will receive single-session administration of tACS during performance of a working memory task. tACS will be applied during memory delays. EEG will be acquired before and immediately after the intervention.
Gamma tACS applied during memory delays
EXPERIMENTALParticipants will receive single-session administration of tACS during performance of a working memory task. tACS will be applied during memory delays. The stimulation will be phase locked to the peaks of ongoing theta rhythms of the participant. EEG will be acquired before and immediately after the intervention.
Placebo tACS applied during task performance
PLACEBO COMPARATORParticipants will receive single-session administration of placebo tACS during performance of a working memory task. EEG will be acquired before and immediately after the intervention.
Interventions
Active tACS will be administered over the left dorsolateral prefrontal cortex for approximately 25 minutes.
Placebo tACS will be administered over the left dorsolateral prefrontal cortex for approximately 25 minutes.
Eligibility Criteria
You may qualify if:
- Able to provide informed consent
- Fluent in English.
You may not qualify if:
- History of a neurological/psychiatric disorder
- Current use of psychotropic medications
- Current use of substances and drugs that were shown to affect tES (transcranial electrical stimulation) efficacy (dopamine altering drugs, nicotine, NMDA (N-methyl-D-aspartate) antagonists/agonists, sodium/calcium channel blockers, norepinephrine reuptake inhibitors, GABAergic modulators and selective serotonin reuptake inhibitors)
- Contraindications for tACS (e.g., history of seizures, metallic implants in the head or neck, implanted brain stimulators, vagus nerve stimulators, pacemakers, pregnancy)
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (1)
Martinos Center for Biomedical Imaging
Charlestown, Massachusetts, 02129, United States
Study Officials
- PRINCIPAL INVESTIGATOR
Hamdi Eryilmaz, Ph.D.
Massachusetts General Hospital
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- RANDOMIZED
- Masking
- DOUBLE
- Who Masked
- PARTICIPANT, OUTCOMES ASSESSOR
- Purpose
- BASIC SCIENCE
- Intervention Model
- CROSSOVER
- Sponsor Type
- OTHER
- Responsible Party
- PRINCIPAL INVESTIGATOR
- PI Title
- Assistant Professor
Study Record Dates
First Submitted
June 20, 2023
First Posted
June 28, 2023
Study Start
July 10, 2024
Primary Completion (Estimated)
August 31, 2026
Study Completion (Estimated)
March 31, 2027
Last Updated
February 9, 2026
Record last verified: 2026-02
Data Sharing
- IPD Sharing
- Will not share