Validation of a Novel Cortical Biomarker Signature for Pain

Study Overview
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Brief Summary
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The study aims to undertake analytical validation of an brain biomarker in healthy participants experiencing a model of sustained temporomandibular pain. The biomarker could detect participants at greater risk of developing more severe pain.

Detailed Description
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Chronic pain is a major health burden associated with immense economic and social costs. Predictive biomarkers that can identify individuals at risk of developing severe and persistent pain, which is associated with worse disability and greater reliance on opioids, would promote aggressive, early intervention that could halt the transition to chronic pain. The investigative team has uncovered evidence of a unique cortical biomarker signature that predicts pain susceptibility (severity and duration). The biomarker signature combines resting state sensorimotor peak alpha frequency (PAF) measured using electroencephalograph (EEG) and corticomotor excitability (CME) measured using transcranial magnetic stimulation (TMS). This PAF/CME biomarker signature could be capable of predicting the severity of pain experienced by an individual minutes to months in the future, as well as the duration of pain (time to recovery). In the current study, the investigators aim to undertake analytical validation of this biomarker in healthy participants using a standardized model of the transition to sustained myofascial temporomandibular pain (masseter intramuscular injection of nerve growth factor). The investigators will record PAF/CME at multiple time points before and during the development of pain and use online diaries and in-laboratory assessments of pain, sleep, stress, and other psychosocial variables. Specifically, the investigators will test if the biomarker signature predicts an individual's pain sensitivity (high- or low-pain sensitive).

Official Title
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Validation of a Novel Cortical Biomarker Signature for Pain

Conditions
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TMD

Intervention / Treatment
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* Other: Injection of Nerve Growth Factor


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: healthy Exclusion Criteria: unable or refusal to provide written consent presence of any acute pain disorder history or presence of any chronic pain disorder history or presence of any other medical or psychiatric compliant use of opioids or illicit drugs in the past 3 months pregnant or lactating women excessive alcohol use contraindicated for TMS (metal implants, epilepsy)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 44 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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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: Injection of Nerve Growth Factor|Injection of Nerve Growth Factor to the right masseter|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Peak pain intensity from diary ratings | Pain sensitivity | 0 to 30 days following NGF injection | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Average Peak daily pain intensity from from diary ratings | Pain severity | 0 to 30 days following NGF injection | 
| The time between pain onset and complete resolution of pain for two consecutive days | Pain duration | 0 to 30 days following NGF injection |