The Effects of taVNS on Inhibitory Control

Study Overview
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Brief Summary
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The main aim of the study is to investigate whether the transcutaneous vagus nerve stimulation(tVNS) improves the ability of inhibitory control in an emotional Go-Nogo task.

Detailed Description
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A randomized, sham-controlled, between-subject design will be employed in this study. A total of 87 healthy subjects will receive either transcutaneous vagus nerve stimulation via tragus or sham stimulation via the earlobe in the left ear. Brain activity and behavioral data for an emotional Go-Nogo task will be recorded and saliva samples will be collected before, during, and after stimulation. Some personal traits will be assessed using different kinds of questionnaires, such as the State-Trait Anxiety Inventory (STAI), Beck's Depression Inventory(BDI), Autism Spectrum Quotient (ASQ) et al.

Official Title
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Transcutaneous Auricular Vagus Nerve Stimulation Improves Inhibitory Control in Emotional Go-Nogo Task

Conditions
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Healthy

Intervention / Treatment
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* Device: Vagus nerve stimulation via tragus
* Device: Sham stimulation via earlobe


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy subjects without past or current psychiatric or neurological disorders Exclusion Criteria: history of head injury; pregnant, menstruating, taking oral contraceptives; medical or psychiatric illness.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 25 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Tragus stimulation<br>Vagus nerve stimulation via tragus | Device: Vagus nerve stimulation via tragus<br>* The device will send stimulus intensity of around 0.5mA via tragus in the left ear (based on participants' subjective report), delivered with a pulse width of 0.5 ms at 25 Hz. Stimulation will be active for 30 seconds, followed by a break of 30 seconds.<br>|
| Sham Comparator: Sham stimulation<br>Sham stimulation via earlobe | Device: Sham stimulation via earlobe<br>* The device will send stimulus intensity of around 0.5mA via the earlobe in the left ear (based on participants' subjective reports), delivered with a pulse width of 0.5 ms at 25 Hz. Stimulation will be active for 30 seconds, followed by a break of 30 seconds.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The ability of inhibitory control in an emotional Go-Nogo task | Analysis the behavioral and brain data recorded during the task | After 30 minutes stimulation | 
| Oxytocin release | Investigating the oxytocin release after taVNS via tragus and earlobe based on saliva samples | within 5 minutes after taVNS via tragus and earlobe |