Learning and Ear Stimulation

Study Overview
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Brief Summary
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This study aims to determine how non-invasive ear stimulation affects learning. During this study, participants will be asked to complete surveys and come to a lab for about 2.5 hours. Researchers will measure brain waves and other body responses (heart rate), while while the ear is stimulated. Participants also will be asked to complete computer tasks. Because brain activity will be measured, participants will be asked to come to the study with clean, dry hair. The study is at MUSC in Charleston. Participants will be compensated for their time. To be eligible, participants must be 18-65 years old, be able to commit 2.5 hours of time to the study, and be able to wear sensors on their hands, arms, and head and sit quietly at a computer. There are some risks to completing this study. Some questions in the surveys ask about personal thoughts and feelings. The ear stimulation may cause tingling sensations or irritation around the ear. There are no direct benefits to participants. This study will help researchers improve this ear stimulation as a treatment method.

Official Title
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Optimizing Transdiagnostic Non-invasive Vagus Nerve Stimulation to Enhance Learning

Conditions
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Learning, taVNS

Intervention / Treatment
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* Device: transcutaneous auricular vagus nerve stimulation (taVNS) 15 minutes
* Device: taVNS 30 minutes
* Device: taVNS 45 minutes
* Device: taVNS 60 minutes
* Device: taVNS 75 minutes
* Device: taVNS 0 minutes


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: English speaking Non-treatment-seeking community members who do not have a mental health diagnosis and individuals seeking treatment for an anxiety, mood, trauma-related, or obsessive-compulsive disorder. Treatment and non-treatment-seeking community members with anxiety, mood, trauma-related, or obsessive-compulsive disorder or symptoms. Exclusion Criteria: Diagnosis of COVID-19 in the past 14 days Facial or ear pain or recent ear trauma Metal implant devices in the head, heart or neck History of brain stimulation or other brain surgery History of myocardial infarction or arrhythmia, bradycardia Use of B-blockers, antiarrhythmic medication (sodium/potassium/calcium-channel blockers), or blood pressure medications. Active respiratory disorder Personal or family history of seizure or epilepsy or personal use of medications that substantially reduce seizure threshold (e.g., olanzapine, chlorpromazine, lithium). Personal history of head injury, concussion, or self-report of moderate to severe traumatic brain injury Individuals suffering from frequent/severe headaches Individuals with lifetime evidence of severe psychiatric disorder (e.g., schizophrenia) or neurological disorder. Moderate to severe alcohol or substance use disorder. Pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Dose Group 1<br> | Device: transcutaneous auricular vagus nerve stimulation (taVNS) 15 minutes<br>* Sham 60 minutes and taVNS active stimulation for 15 minutes<br>|
| Other: Dose Group 2<br> | Device: taVNS 30 minutes<br>* Sham 45 minutes and taVNS active stimulation for 30 minutes<br>|
| Other: Dose Group 3<br> | Device: taVNS 45 minutes<br>* Sham 30 minutes and taVNS active stimulation for 45 minutes<br>|
| Other: Dose Group 4<br> | Device: taVNS 60 minutes<br>* Sham 15 minutes and taVNS active stimulation for 60 minutes<br>|
| Other: Dose Group 5<br> | Device: taVNS 75 minutes<br>* Sham 0 minutes and taVNS active stimulation for 75 minutes<br>|
| Other: Dose Group 6<br> | Device: taVNS 0 minutes<br>* Sham taVNS 75 minutes<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Heart Rate |  | Baseline to Active Stimulation (10-80 minutes apart) and Baseline to Recovery (90 minutes apart) | 
| Change in Skin Conductance Levels | Galvanic Skin Response measured in micro Siemens (mS) | Baseline to Active Stimulation (10-80 minutes apart) and Baseline to Recovery (90 minutes apart) | 
| Change in P300 Amplitude | Measured for standard versus deviant tones during the Auditory Oddball Task. Oddball will be administered at 3 intervals during stimulation. | Measured at 20-30, 50-60, and 80-90 minutes during stimulation | 
| Pupillometry (Pupil Response) | Tonic Pupil Size and Event-Related Pupil Dilation measured in millimeters (mm) | Baseline to Active Stimulation (10-80 minutes apart) and Baseline to Recovery (90 minutes apart) |