Purpose

This study investigates whether transcranial electrical stimulation (tES) delivered during structured language-learning sessions affects the rate and quality of second-language acquisition in adults. Adults who are learning or planning to learn a new language are randomly assigned in equal numbers to receive either active stimulation or sham (placebo) stimulation while completing structured language-learning content. Participants wear a non-invasive transcranial electrical stimulation headset that delivers a low-level electrical current through electrodes resting on the scalp, targeting cortical regions associated with language. Sessions typically last 20 to 30 minutes and may be completed at home or in person at a participating language program. Language proficiency is measured with a standardized assessment before and after the intervention period, with additional app-derived performance metrics and participant-reported measures collected throughout. A follow-up assessment may be conducted up to 12 months after the intervention ends to evaluate whether any observed effects persist. In this study the device is applied as a learning aid in healthy adults. It is not used to diagnose, treat, cure, or prevent any disease.

Conditions

Eligibility

Eligible Ages
Over 18 Years
Eligible Sex
All
Accepts Healthy Volunteers
Yes

Inclusion Criteria

  • Adults aged 18 years or older - Able to understand the consent materials and the informed consent process in English, or in another language for which an IRB-approved consent form is available - Willing and able to participate in structured language-learning activities for the duration of the intervention period - Able to provide written informed consent

Exclusion Criteria

  • History of epilepsy or any seizure disorder - Active skin disease, open wounds, or significant skin irritation at electrode contact sites - Implanted electronic medical devices where stimulation would be contraindicated per device manufacturer guidance or investigator judgment after individual risk assessment - Significant cognitive impairment that would interfere with informed consent or study participation - Any other condition that, in the investigator's judgment, would compromise participant safety or the integrity of the study data

Study Design

Phase
N/A
Study Type
Interventional
Allocation
Randomized
Intervention Model
Parallel Assignment
Intervention Model Description
Two parallel arms, active tES and sham tES, each paired with the same structured language-learning content. Participants are randomized 1:1, with stratification by site or cohort as applicable.
Primary Purpose
Basic Science
Masking
Triple (Participant, Investigator, Outcomes Assessor)
Masking Description
The Sub-Investigator holds the stimulation assignment and is not masked. Assignment is not disclosed to the Principal Investigator until all outcome data are collected and locked and primary analyses are finalized.

Arm Groups

ArmDescriptionAssigned Intervention
Experimental
Active Stimulation
Participants receive active transcranial electrical stimulation delivered through a non-invasive scalp-mounted headset while completing structured language-learning content. Stimulation amplitude and session duration are selected per cohort from the declared parameter envelope, with current ramping at session start and end. Sessions are typically 20 to 30 minutes.
  • Device: Active transcranial electrical stimulation (tES)
    Non-invasive transcranial electrical stimulation delivered by a scalp-mounted headset within the LOTES-2023 limited-output envelope, paired with structured language-learning content. Adult declared range 0 to 4 mA average absolute current, maximum current density 2 mA/cm2 at the electrode contact area, and maximum session duration 60 minutes subject to a 6000 mC per-session total charge limit. Electrodes are placed in standard cephalic or extracephalic montages targeting the left perisylvian region and adjacent association cortex.
Sham Comparator
Sham Stimulation
Participants receive sham stimulation through the same non-invasive scalp-mounted headset while completing the same structured language-learning content. Sham provides the sensory experience of stimulation onset without sustained current delivery. The specific validated sham approach is selected and documented per cohort.
  • Device: Sham transcranial electrical stimulation (tES)
    Sham stimulation delivered by the same scalp-mounted headset, providing the initial cutaneous sensory experience of stimulation onset without sustained current delivery, paired with the same structured language-learning content. The specific validated sham approach is selected per cohort and documented in the corresponding cohort plan.

Recruiting Locations

General Neuro, Inc.
Boston, Massachusetts 02131
Contact:
Alec Sheffield, PhD
617-657-3348
info@generalneuro.com

More Details

Status
Recruiting
Sponsor
General Neuro Inc.

Study Contact

Alec Sheffield, PhD
617-657-3348
alec@generalneuro.com

Detailed Description

The study is a prospective, randomized, double-blind, sham-controlled investigation. Participants are randomized 1:1 to active or sham stimulation, with stratification by site or cohort as applicable. Neither participants nor the research team conducting outcome assessments are aware of assignment during data collection. Stimulation assignment is held by the Sub-Investigator and is not disclosed to the Principal Investigator until all outcome data are collected and locked and primary analyses are finalized. Sessions may be delivered by decentralized at-home administration, on-site administration at partner language programs and educational institutions, or a hybrid of the two. The protocol declares a bounded parameter envelope within which specific stimulation parameters, learning content, partner sites, and assessment instruments may be selected per cohort without protocol amendment. All parameters operate within the LOTES-2023 limited-output standard for transcranial electrical stimulation devices. For adult participants the declared envelope permits 0 to 4 mA average absolute current, a maximum current density of 2 mA/cm2 at the electrode contact area, and a maximum session duration of 60 minutes subject to a 6000 mC total-charge-per-session ceiling. Anticipated session durations are 20 to 30 minutes. Any modality within the transcranial electrical stimulation family may be used, including tDCS, tACS, tRNS, and tPCS. Intended cortical targets are the left perisylvian region and adjacent association cortex, including Broca's area and Wernicke's area. Montages use standard cephalic or extracephalic placements with at least one electrode positioned on the head. Because assessment instruments and specific stimulation parameters are selected per cohort within the declared envelope, each enrollment cohort has a cohort-specific Statistical Analysis Plan finalized and locked prior to unblinding of that cohort.

Notice

Study information shown on this site is derived from ClinicalTrials.gov (a public registry operated by the National Institutes of Health). The listing of studies provided is not certain to be all studies for which you might be eligible. Furthermore, study eligibility requirements can be difficult to understand and may change over time, so it is wise to speak with your medical care provider and individual research study teams when making decisions related to participation.