Is Nociceptive Processing Evoked by Heat Homeostatically Regulated: A Contact-heat Evoked Potentials Study
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 18
- 试验地点
- 1
- 主要终点
- Contact Heat Evoked Potentials
研究概览
简要总结
Homeostatic plasticity is a mechanism that stabilizes neuronal activity to prevent excessive nervous system excitability. This mechanism can be investigated in humans by applying two blocks of non-invasive brain stimulation, such as transcranial direct current stimulation (tDCS).
In healthy subjects, homeostatic plasticity induction over the primary motor cortex increases the amplitude of motor-evoked potentials after the first block of excitatory tDCS, which then decreases after the second block of excitatory tDCS. However, this mechanism is impaired in chronic and experimental pain, demonstrated by an increase in excitability instead of a reversal.
The role of homeostatic plasticity mechanisms in pain is yet to be unraveled, but homeostatic plasticity may hold an important role in pain development or persistence.
Thus, the aim of this study is to investigate if the cortical nociceptive response reflected by contact heat stimulation (CHEPs) is regulated by homeostatic mechanisms. For this, homeostatic plasticity will be induced in both the primary motor (M1) and sensory cortices (S1). The first research question will explore if the contact heat evoked potentials are homeostatically regulated and if this regulation is occurring locally or globally in the cortex. Additionally, it will be investigated if and how capsaicin-induced nociception interacts and effects the homeostatic response as reflected by CHEPs.
详细描述
Randomized, cross-over study of four 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
- Single (Participant)
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 right-handed men and women aged 18-60 years
- •Speak, read, and understand English or Danish
排除标准
- •Pregnant, breastfeeding, or women in childbearing age not using contraceptive methods
- •Regular use of cannabis, opioids or other drugs (except contraceptives)
- •Current or previous neurologic, musculoskeletal, mental, or other illnesses (e.g. brain or spinal cord injuries, degenerative neurological disorders, epilepsy, major depression, cardiovascular disease, chronic lung disease, etc.)
- •Current or previous chronic or recurrent pain condition (other than low back pain in patients recruited for sub-project 6, and this item does not apply to sub-project 8)
- •Current regular use of analgesic medication or other medication which may affect the trial (including paracetamol and NSAIDs) For subproject 8, chronic low back pain patients may take analgesic medication provided the dosage is stable
- •Open wounds, eczema, scars, or tattoos in the area of the heat stimulation (sub-project 1)
- •Lack of ability to cooperate
- •Recent history of acute pain particularly in the lower limbs (unless related to low back pain in patients included in sub-project 6 or 8)
- •Abnormally disrupted sleep in 24 hours preceding experiment
- •Any medical or other condition (i.e. musculoskeletal, cardiorespiratory, neurological, etc.)
- •Contraindications to TMS application (history of epilepsy, metal implants in head or jaw, etc.)
- •Unable to answer to the "Transcranial Magnetic Stimulation Adult Safety Screen" or tDCS screening questionnaire (see Bilag_v1_06092021)
研究组 & 干预措施
S1 Homeostatic Plasticity-Sham
Sham tDCS C3 FP2
4x4 patch on the dorsum of the hand
干预措施: Homeostatic Plasticity (Sham) (Other)
S1 Homeostatic Plasticity-Pain
Anodal tDCS CP3 1mA FP2 -1mA
4x4 patch on the dorsum of the hand
干预措施: Homeostatic Plasticity (Other)
S1 Homeostatic Plasticity-Pain
Anodal tDCS CP3 1mA FP2 -1mA
4x4 patch on the dorsum of the hand
干预措施: Topical alone (Capsaicin 8% Patch) (Drug)
S1 Homeostatic Plasticity-NoPain
Anodal tDCS C3 1mA FP2 -1mA
4x4 patch on the dorsum of the hand
干预措施: Homeostatic Plasticity (Other)
S1 Homeostatic Plasticity-NoPain
Anodal tDCS C3 1mA FP2 -1mA
4x4 patch on the dorsum of the hand
干预措施: Placebo Patch (Other)
S1 Homeostatic Plasticity-Sham
Sham tDCS C3 FP2
4x4 patch on the dorsum of the hand
干预措施: Placebo Patch (Other)
M1 Homeostatic Plasticity
Anodal tDCS C3 1mA FP2 -1mA
4x4 patch on the dorsum of the hand
干预措施: Homeostatic Plasticity (Other)
M1 Homeostatic Plasticity
Anodal tDCS C3 1mA FP2 -1mA
4x4 patch on the dorsum of the hand
干预措施: Placebo Patch (Other)
结局指标
主要结局
Contact Heat Evoked Potentials
时间窗: 10 minutes after the homeostatic plasticity protocol
Post-HP+10 minutes (Evoked Potentials after stimulus onset from electroencephalographic channels)
次要结局
- Pain Intensity After Stimulation Blocks(0 minutes after the fifth block of CHEP stimulation)
- Presence of Allodynia After Stimulation Blocks(0 minutes after the fifth block of CHEP stimulation)
- Pain Intensity After Stimulation Blocks (0-10)(0 minutes after the second block of CHEP stimulation)
- Pittsburg Sleeping Quality Index(Pre-intervention and pre-patch application)
- BECKS Depression Inventory(Pre-intervention and pre-patch application)
- Positive and Negative Affective Schedule - Short Form(Pre-intervention and pre-patch application)
- State-Trait Anxiety Inventory(Pre-intervention and pre-patch application)
- Pain Catastrophizing Scale(Pre-intervention and pre-patch application)
- Pain intensity (Induced by Capsaicin)(Throughout the experimental session, every 5 minutes and up to 55 minutes after patch application)
研究者
Daniela Montemayor Zolezzi
Principal Investigator
Aalborg University