Non-Invasive Brain Stimulation

Study Overview
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Brief Summary
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The study focusses on utilizing neuroimaging modalities, including Electroencephalography (EEG) and Functional Magnetic Resonance Imaging (fMRI) to study the impact of non-invasive brain stimulation on the prefrontal cortex during a cognitive task.

Detailed Description
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In this study, a total of 40 subjects will be randomly assigned to 2 groups i.e. experimental and sham. Conventional transcranial direct current stimulation (c-tDCS) and high-definition transcranial direct current stimulation (HD-tDCS) will be used to stimulate the prefrontal cortex of the brain. EEG and fMRI will be collected before, during and after stimulation to understand the impact of stimulation on brain dynamics. The investigators hypothesize that the stimulation of the prefrontal cortex will improve performance during cognitive tasks along with changes in the neural processing detected by neuroimaging modalities.

Official Title
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Effect of Conventional Transcranial Direct Current Stimulation (c-tDCS) and High-definition Transcranial Direct Current Stimulation (HD-tDCS) on the Prefrontal Cortex

Conditions
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Stroke

Intervention / Treatment
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* Device: Transcranial Direct Current Stimulator


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Right Handedness, Age > 18 Exclusion Criteria: History of any other neurological disease, Any psychological or psychiatric disease, Significant visual or auditory impairments, tDCS contraindications including implanted metallic or electronic devices, seizures or convulsions, and pregnancy.

Ages Eligible for Study
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Minimum Age: 18 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: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Stimulation Group<br> | Device: Transcranial Direct Current Stimulator<br>* Transcranial Direct Current Stimulation (tDCS) is a non-invasive brain stimulation device that can excite or inhibit the brain activity depending on the stimulation protocol. It has mainly two variants including conventional c-tDCS and High-Definition HD-tDCS.<br>|
| Sham Comparator: Control Group<br> | Device: Transcranial Direct Current Stimulator<br>* Transcranial Direct Current Stimulation (tDCS) is a non-invasive brain stimulation device that can excite or inhibit the brain activity depending on the stimulation protocol. It has mainly two variants including conventional c-tDCS and High-Definition HD-tDCS.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reaction Time (RT) | Reaction time of the subject during a cognitive task would be a measure to assess changes in performance due to stimulation | 1 hour | 
| Concentration Rate | The percentage of accurate responses during the cognitive task within the stipulated time will be calculated to see an impact on concentration after stimulation | 1 hour | 
| Event related potential latency and amplitude | Changes in latency and amplitude of event related potentials including P300 & N200 would be used as neural marker to understand cognitive processing in the brain. | 1 hour | 
| Functional Magnetic Resonance Imaging (fMRI) | Changes in fMRI connectivity | 1 hour |