Effect of Transcutaneous Auricular Vagus Nerve Stimulation on Food Intake: A Randomized, Double-Blind, Sham-Controlled Crossover Study
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 60
- 试验地点
- 1
- 主要终点
- Difference in Food Intake
研究概览
简要总结
This study tests a new way to help control appetite. Researchers will use a wearable device on the ear. This device sends gentle electrical pulses to a nerve. This is called vagus nerve stimulation.
The main goals of this study are:
- To see if this device helps people eat less.
- To check if it lowers feelings of hunger.
- To measure how it changes responses to food cues.
Healthy adult women will join this study. Each person will have two study visits. At one visit, the device will be turned on. At the other visit, the device will be off. This is a fake or "sham" treatment.
During each visit, researchers will:
- Give a standard meal for 30 minutes.
- Measure how much food each person eats.
- Ask questions about hunger and fullness.
- Use computer tasks to check food cravings.
This study may find a safe, medicine-free way to manage eating habits.
详细描述
Background and Rationale Despite substantial advances in pharmacological treatments for obesity, a considerable proportion of individuals remain non-responsive or intolerant to current medications. This highlights the urgent need for novel, sustainable, and non-pharmacological interventions. Transcutaneous auricular vagus nerve stimulation (taVNS) is an emerging non-invasive electroceutical approach. It targets the vagal afferent pathway to modulate the brain-gut axis, potentially influencing appetite regulation through neurophysiological circuits related to satiety, reward, and interoceptive processing.
Study Protocol and Procedures This study employs a double-blind, sham-controlled, crossover design. Participants will complete two separate experimental visits, separated by a washout period of at least 24 hours to prevent carryover effects. The sequence of the active and sham conditions will be strictly counterbalanced across participants.
During each experimental session, participants will first undergo baseline assessments. Following baseline, the investigational wearable device will be applied to the participant's ear. For the active condition, stimulation will be targeted at the left cymba conchae. The device is programmed with specific technical parameters, including a frequency of 20 Hz, a 50% duty cycle, and an intensity of 1 mA. For the sham condition, the setup will be identical in appearance but will lack the therapeutic electrical dosage to maintain double-blinding for both the investigator and the participant.
The designated stimulation (active or sham) will be delivered continuously for exactly 30 minutes. Concurrently with the stimulation, participants will be presented with a standardized, ad libitum buffet-style test meal. Immediately following the 30-minute eating and stimulation session, participants will engage in a series of computerized cognitive-behavioral tasks and state-assessment surveys designed to capture neurocognitive responses to food cues and interoceptive awareness.
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
- Single (Investigator)
入排标准
- 年龄范围
- 20 Years 至 50 Years（Adult）
- 性别
- Female
- 接受健康志愿者
- 是
入选标准
- •Female participants aged between 20 and 50 years
- •Body Mass Index (BMI) of 20 or higher
- •Individuals who are capable of understanding the study procedures and providing voluntary informed consent
排除标准
- •Presence of implanted metallic or electronic medical devices (e.g., cardiac pacemaker, implantable cardioverter defibrillator (ICD), cardiac stent, deep brain stimulator, or cochlear implant), except for dental implants and artificial joints
- •History of diagnosed psychiatric disorders or current use of psychiatric medications
- •Moderate to severe depression symptoms, defined as a Patient Health Questionnaire-9 (PHQ-9) score of 10 or higher
- •Use of medications or medical interventions that may induce weight changes within the past 3 months
- •Active inflammatory or infectious lesions on the ear (e.g., otitis externa, auricular dermatitis, or active skin infection)
- •Specific dietary habits or restrictions, such as being a vegan or vegetarian
- •Known food allergies
- •Currently pregnant or breastfeeding
- •History of diagnosed diabetes or other endocrine metabolic diseases
- •Any other medical condition, illness, or history that, in the investigator's judgment, would make it difficult for the participant to complete the study or complicate the interpretation of study results
研究组 & 干预措施
Active then Sham
Participants receive a single 30-minute session of active taVNS in the first period. Following a washout period of at least 24 hours to prevent carry-over effects, they return for a second visit to receive a single 30-minute session of sham stimulation.
干预措施: Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) (Device)
Active then Sham
Participants receive a single 30-minute session of active taVNS in the first period. Following a washout period of at least 24 hours to prevent carry-over effects, they return for a second visit to receive a single 30-minute session of sham stimulation.
干预措施: Sham Stimulation (Device)
Sham then Active
Participants receive a single 30-minute session of sham stimulation in the first period. Following a washout period of at least 24 hours, they return for a second visit to receive a single 30-minute session of active taVNS.
干预措施: Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) (Device)
Sham then Active
Participants receive a single 30-minute session of sham stimulation in the first period. Following a washout period of at least 24 hours, they return for a second visit to receive a single 30-minute session of active taVNS.
干预措施: Sham Stimulation (Device)
结局指标
主要结局
Difference in Food Intake
时间窗: During the 30-minute ad libitum meal session in each experimental visit
The amount of food consumed during an ad libitum buffet meal (standardized Gimbap). It is calculated as the difference in the weight of food (grams) consumed between the active taVNS session and the sham stimulation session.
次要结局
- Attentional Bias Toward Food Stimuli(Immediately after the 30-minute stimulation/meal session.)
- custom-developed Interoceptive State Appetite Scale (VAS-100)(Baseline (pre-stimulation) and immediately after the 30-minute stimulation/meal session.)
- Eating-Related Interoceptive Awareness(Immediately after the ad libitum buffet meal and the final VAS-100 appetite assessment in each experimental session.)
- Inhibitory Control Toward Food Cues: False Alarm Rate(Immediately after dot probe task)
- Inhibitory Control Toward Food Cues: d-prime(Immediately after the Dot-probe task)