A Sham-Controlled Cross-Over Study Examining the Effects of Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) on Cognitive Performance and Gender Differences in Healthy Adults
试验速览
- 阶段
- 不适用
- 状态
- 尚未招募
- 发起方
- 入组人数
- 60
- 主要终点
- CogniFit Digital Battery
研究概览
简要总结
This study investigates the effects of transcutaneous auricular vagus nerve stimulation (taVNS) on cognitive performance in healthy adults. The study uses a sham-controlled, cross-over design in which each participant receives both active taVNS and sham stimulation in separate sessions. Each participant completes both conditions (active and sham) in a randomized order using a crossover design. Cognitive performance will be assessed before and after each session using standardized tests. The study also explores whether males and females respond differently to taVNS, in order to identify potential sex-related differences in cognitive outcomes.
详细描述
This randomized, sham-controlled cross-over study investigates the effects of transcutaneous auricular vagus nerve stimulation (taVNS) on cognitive performance, autonomic activity, and psychological state in healthy young adults, with specific attention to sex differences. Because hormonal fluctuations may influence vagal tone and cognitive outcomes, female participants are required to complete their stimulation sessions during the follicular phase (Day 5-10) of the menstrual cycle. Male participants follow the same protocol without timing restrictions.
The study consists of three laboratory visits, scheduled one week apart.
Visit 1 (Baseline Assessments):
Participants provide informed consent and complete a demographic questionnaire, menstrual-cycle verification (for female participants), the Montreal Cognitive Assessment (MoCA), and baseline psychological questionnaires including the State-Trait Anxiety Inventory (STAI) and the Perceived Stress Scale (PSS). Baseline cognitive performance is measured using the CogniFit digital battery.
Visits 2 and 3 (Randomized Cross-Over Stimulation Sessions):
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- Double (Participant, Outcomes Assessor)
盲法说明
Participants will be blinded to whether they receive active or sham stimulation. Outcome measures (CogniFit, HRV, STAI, PSS) are automated or self-administered; outcome assessors will therefore be blinded to condition. The investigator applying stimulation will not be blinded due to device setup requirements.
入排标准
- 年龄范围
- 18 Years 至 30 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Healthy young adults aged 18-30 years
- •Ability to provide informed consent
- •Right-handed participants (to reduce variability in cognitive performance)
- •Normal or corrected-to-normal vision and hearing
- •Female participants tested during the follicular phase of the menstrual cycle (days 5-10) to minimize hormonal effects on cognition and vagal tone
排除标准
- •History of neurological or psychiatric disorders
- •Cardiovascular disease
- •Use of psychoactive medications
- •Substance dependence, including alcohol, illicit drugs, or nicotine
- •Pregnancy or breastfeeding
- •Skin conditions or ear anomalies that interfere with electrode placement
- •Metal implants in the head or neck region
- •History of epilepsy or migraine
研究组 & 干预措施
Active taVNS Stimulation
Active taVNS will be applied bilaterally to the cymba conchae and tragus regions using the VaguStim device. Stimulation will follow standard parameters used in cognitive studies to minimize cardiac side effects. Parameters: biphasic waveform, 25 Hz frequency, 250 μs pulse width, and intensity individually adjusted below the sensory threshold (0.5-4 mA). Each session will last 20 minutes.
干预措施: Active taVNS (Device)
Sham Stimulation
For the sham condition, electrodes will be placed on the earlobe bilaterally, an area not innervated by the vagus nerve, using the same device and parameter settings but without delivering active stimulation. This setup controls for placebo effects.
干预措施: Sham Stimulation (Device)
结局指标
主要结局
CogniFit Digital Battery
时间窗: Day 1 (Visit 1 baseline), Day 8 (Visit 2), and Day 15 (Visit 3) Cognitive testing will occur after stimulation on Day 8 and Day 15.
Cognitive performance will be evaluated using the CogniFit digital cognitive battery, which assesses multiple cognitive domains including attention, working memory, executive functions, and processing speed. The battery will be administered once at baseline (Visit 1). It will be administered again immediately after Active stimulation in Visit 2 and immediately after Sham stimulation in Visit 3. Changes in cognitive scores between baseline and post-stimulation sessions will be compared to determine the acute cognitive effects of active vs. sham taVNS.
次要结局
- State and Trait Anxiety (STAI)(Day 1 (Visit 1 baseline), Day 8 (Visit 2 after stimulation), and Day 15 (Visit 3 after stimulation).)
- Heart Rate Variability (HRV)(Day 8 (Visit 2): 5 minutes before stimulation and 5 minutes after stimulation. Day 15 (Visit 3): 5 minutes before stimulation and 5 minutes after stimulation.)
- Perceived Stress Levels (PSS)(Day 1 (Visit 1 baseline), Day 8 (Visit 2 after stimulation), and Day 15 (Visit 3 after stimulation).)
- Self-Reported Side Effects(Day 8 (Visit 2 after stimulation) and Day 15 (Visit 3 after stimulation))
研究者
Yara Atef Skout
Principal investigator
Bahçeşehir University