Investigation of the Neurophysiological and Psychological Aspects of Itch
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 30
- 试验地点
- 2
- 主要终点
- Measuring corticospinal excitability
研究概览
简要总结
The experiment consists of three experimental sessions conducted over a period of two weeks. In the first experimental session, we apply in your hand: either an injection of salt water (7% NaCl) or we apply small needles from the plant mucuna pruriens or histamine (1%). For 10 minutes after this, you are to assess the itch and pain you perceive. We will also apply non-invasive magnetic stimulations to your brain. During the experiment, you should fill in questionnaires. The second and third experimental sessions are conducted in the same way as the first session.
The purpose of this experiment is to investigate the changes appearing in the brain during artificially applied itch and pain corticomotor adaptations.
详细描述
The experiment consists of three experimental sessions conducted over a period of two weeks. The duration of each session is approx. two hours. In the first experimental session, we apply one of three experimental methods in your hand: either an injection of salt water (7% NaCl) or we apply small needles from the plant mucuna pruriens or histamine (1%) Histamine is an itch-provoking substance formed in the human body. For 10 minutes after this, you are to assess the itch and pain you perceive on a scale from 0 to 10, in which 0 is no itch/pain and 10 is worst itch/pain imaginable. We will also apply non-invasive magnetic stimulations to your brain. This is done using a magnetic coil which is held over your head. During the experiment, you should fill in questionnaires about how you experience itch/pain and about your personality. The second and third experimental sessions are conducted in the same way as the first session. However, we will apply one of the other two experimental methods than the one used in the first session (i.e., first session: histamine, second session: plant needles, third session: injection with salt water). The experimental methods will be applied in random order.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 60 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Healthy men and women
- •18-60 years
- •Speak and understand English
排除标准
- •Pregnancy or lactation
- •Drug addiction defined as any use of cannabis, opioids, or other addictive drugs
- •Previous or current history of neurological (e.g. neuropathy), immunological (e.g. asthma, immune deficiencies, arthritis), musculoskeletal (e.g. muscular pain in the upper extremities,), cardiac disorder (e.g., heart stroke), or psychiatric diagnoses (e.g. depression) that may affect the results
- •Current use of medications that may affect the trial, such as antihistamines, antipsychotics, and painkillers, as well as systemic or topical steroids
- •Skin diseases (e.g., atopic dermatitis, pruritus nodularis, eczema, psoriasis)
- •Moles, scars, or tattoos in the area to be treated or tested.
- •Consumption of alcohol or painkillers 24 hours before the study days and between these
- •Acute or chronic pain
- •Unable to pass the "Transcranial Magnetic Stimulation Adult Safety Screen" (subproject 1 and 2)
- •Contraindications to transcranial magnetic stimulation (TMS) application (history of epilepsy, metal implants in head or jaw, etc.) (subproject 1 and 2)
- •Presence of implanted hearing aids or metal implants on the face, including permanent makeup or tattoos (subproject 1 and 2)
- •Participation in other trials within one week of study entry (four weeks in the case of pharmaceutical trials)
- •Lack of ability to cooperate
结局指标
主要结局
Measuring corticospinal excitability
时间窗: post induction (30 minutes)
Transcranial magnetic stimulation (TMS) will be used to evoke motor-evoked potentials (MEPs) in the muscle of interest and cortical responses (TMS-evoked potentials - TEPs) in the motor cortex with a figure-eight-shaped cone coil.
electromyography (EMG) recordings
时间窗: 1 minute after every itch/pain induction
For electromyography (EMG) recordings, two electrodes (Disposable Electrode Pack - AMBU Neuroline 720) will be placed on the muscle belly of the FDI muscle. The reference electrode will be placed on the ulnar styloid process of the left arm.
Numeric rating scales (NRS)
时间窗: 1 minute after every itch/pain induction
NRS are essentially VAS but have tick marks spaced every centimeter so as to create 11-point scale (from 0 to 10). Subject can use these tick marks as a guide when they mark their severity on the scale.
次要结局
- Pain Catastrophizing Scale (PCS).(Baseline)
- Itch Catastrophizing Scale (ICS).(Baseline)
- Learned Helplessness Scale (LHS)(Baseline)
- Positive And Negative Affect Schedule (PANAS)(Baseline)
- The Pittsburg Sleep Quality Index (PSQI)(Baseline)
- Reinforcement Sensitivity Theory - Personality Questionnaire (RST-PQ).(Baseline)
- Depression, Anxiety, Stress Scale (DASS-21)(Baseline)
研究者
Silvia Lo Vecchio
Associate Professor
Aalborg University