Phase Locked TRanscranial Electrical EXcitation

Study Overview
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Brief Summary
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Transcranial current stimulation (tCS) has been extensively studied due to its potential of selectively stimulate brain regions in a non-invasive way. However, classic stimulation paradigms are often applied in an open loop configuration, without considering the effects on the underlying brain activity. Recent studies suggest that when alternating current are used, it would be beneficial to phase lock the stimulation to the target brain wave of interest to achieve selective temporal stimulation, allowing for better control over the stimulation effects. This study aims at demonstrating a novel setup that allows for precise stimulation targeted in space and time. To achieve that, a combination of tCS and (EEG phased locked) closed-loop modality are used to obtain the required selectivity.

Official Title
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T-REEX: Phase Locked TRanscranial Electrical EXcitation

Conditions
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Novel Method for Transcranial Brain Stimulation

Intervention / Treatment
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* Device: T-REEX algorithm


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Signed informed consent Age between 18 and 64 Exclusion Criteria: Wounded or particular sensitive skin at areas of investigation. For example, skinrash, discoloration, scars, or open wounds Allergies to adhesive or dry electrodes or silver chloride Pregnant or lactating Any of the following symptoms (fever, tiredness, dry cough, aches and pains, nasal congestion, runny nose, sore throat, diarrhoea) Known neurological disorders Previous epileptic episodes Active implants such as pacemakers or brain stimulators Intracranial metal implants

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 64 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Device Feasibility
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intervention<br>The study is open label all participants get the same intervention | Device: T-REEX algorithm<br>* Phase locked transcranial stimulation.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The phase difference (error) between the estimated phase of EEG activity and the phase of the delivered stimulation at the target locationor EEG readout and tCS stimulation |  | 2 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the amount of phase and/or amplitude change in the brain wave of interest (e.g., 10 Hz alpha activity) resulting from different tCS modalities and stimulation parameters used |  | 2 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Brain stimulation, Closed-loop, Brain activity