Pain Beliefs and Intracortical Excitability During Experimental Pain

NCT07688525 | Not Yet Recruiting DMC

• 1 other identifier: 2027-6267
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

Pain can influence the way the motor system functions. However, responses to pain vary widely between individuals, and this variability may be partly related to pain-related beliefs such as kinesiophobia. This study examines whether temporary experimental pain changes intracortical excitability in the motor cortex, and whether this response differs according to baseline kinesiophobia. Healthy adults will complete one experimental session. Motor cortex excitability will first be assessed at baseline using transcranial magnetic stimulation, a non-invasive brain stimulation technique. A topical capsaicin cream will then be applied to the forearm to induce temporary, moderate experimental pain. Once pain is established, the same neurophysiological assessments will be repeated. The main objective is to measure changes in short-interval intracortical inhibition before and during capsaicin-induced pain, with particular attention to whether these changes are associated with baseline kinesiophobia. Secondary objectives are to characterize other markers of motor cortex excitability, including long-interval intracortical inhibition, short-interval intracortical facilitation, intracortical facilitation, and corticospinal excitability assessed using input-output recruitment curves. Pain intensity will be monitored using a visual analog scale to characterize the experimental pain response. Baseline kinesiophobia will be assessed using the Tampa Scale of Kinesiophobia and examined as a factor associated with interindividual variability in neurophysiological responses to experimental pain. The researchers expect that changes in motor cortex excitability during experimental pain will vary between individuals, and that individuals with higher kinesiophobia may show smaller changes in motor cortex excitability during capsaicin-induced pain.

Conditions

Kinesiophobia (Fear of Movement); Experimental Pain

Keywords

Experimental pain; Topical capsaicin; Kinesiophobia; Fear of movement; Motor cortex excitability; Intracortical excitability; Corticospinal excitability; Transcranial magnetic stimulation

Outcome Measures

Primary Outcomes (1)

• Change in Short-Interval Intracortical Inhibition

  Short-interval intracortical inhibition will be assessed using paired-pulse transcranial magnetic stimulation over the primary motor cortex, with electromyographic recordings from the first dorsal interosseous muscle. A subthreshold conditioning stimulus set at 80% of resting motor threshold will be followed by a suprathreshold test stimulus set at 120% of resting motor threshold, with an interstimulus interval of 3 ms. Fifteen conditioned trials will be recorded for this measure. The outcome will be expressed as the change in conditioned motor evoked potential amplitude relative to the unconditioned test response from pre- to post-application of topical capsaicin cream.

  At baseline (before capsaicin cream application); at pain stabilization (after capsaicin cream application)

Secondary Outcomes (5)

• Change in Short-Interval Intracortical Facilitation

  At baseline (before capsaicin cream application); at pain stabilization (after capsaicin cream application)

• Change in Pain Intensity

  From baseline through completion of the experimental session, an average of 2 hours

• Change in Intracortical Facilitation

  At baseline (before capsaicin cream application); at pain stabilization (after capsaicin cream application)

• Change in Long-Interval Intracortical Inhibition

  At baseline (before capsaicin cream application); at pain stabilization (after capsaicin cream application)

• Change from baseline in corticospinal excitability

  At baseline (before capsaicin cream application); at pain stabilization (after capsaicin cream application)

Other Outcomes (2)

• Kinesiophobia

  Baseline

• Pain catastrophizing related to pain

  Baseline

Study Arms (1)

Experimental pain

EXPERIMENTAL

Participants complete one experimental session. Motor cortex excitability is first assessed at baseline using transcranial magnetic stimulation with electromyographic recordings from the first dorsal interosseous muscle. Topical capsaicin cream is then applied to the forearm to induce temporary, moderate experimental pain. Once pain is established, the same neurophysiological assessments are repeated during the pain condition.

Drug: Topical Capsaicin Cream (1%)

Interventions

Topical Capsaicin Cream (1%) DRUG

Topical capsaicin cream (1%) is applied to the forearm to induce temporary, moderate experimental pain. Motor cortex excitability is assessed before and during capsaicin-induced pain using transcranial magnetic stimulation.

Experimental pain

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Aged 18 to 35 years, inclusive
• Healthy
• Able to understand the study information and experimental procedures
• Able to provide informed consent

You may not qualify if:

• History of psychiatric disorders (including intellectual disability or severe cognitive, behavioral, or affective impairment) that could interfere with understanding the study or providing informed consent.
• History of neurological disorders, including epilepsy, stroke, brain or spinal cord surgery, or any neurological disease affecting motor or sensory function.
• Inability to provide informed consent (e.g., dementia, significant hearing impairment, insufficient language proficiency).
• Any pain condition within the past 3 months, regardless of origin.
• Recent musculoskeletal injury or surgery within the past 3 months.
• Contraindications to transcranial magnetic stimulation (TMS), including a history of epilepsy or the presence of intracranial metallic objects, cochlear implants, or other non-removable metallic implants in or near the head.
• Use of analgesic or psychotropic medications.
• Individuals under legal guardianship or curatorship.
• Pregnant or breastfeeding women.
• Presence of a cardiac pacemaker or other implanted electronic medical device.
• Known allergy or previous skin reaction to capsaicin

Sponsors & Collaborators

• Université de Sherbrooke: lead

Study Sites (1)

Université de Sherbrooke - Campus de la santé

Sherbrooke, Quebec, J1H 5H3, Canada

Location

MeSH Terms

Conditions

Kinesiophobia

Condition Hierarchy (Ancestors)

Phobic Disorders; Anxiety Disorders; Mental Disorders

Study Officials

• Guillaume Léonard, Ph.D.

  Université de Sherbrooke

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Guillaume Léonard, Ph.D.

CONTACT

819-821-8000; guillaume.leonard2@usherbrooke.ca

Adrien Nourry

CONTACT

+33611074458; adrien.nourry@usherbrooke.ca

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: June 25, 2026
• First Posted: July 7, 2026
• Study Start: August 1, 2026
• Primary Completion (Estimated): November 30, 2026
• Study Completion (Estimated): December 31, 2026
• Last Updated: July 7, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will not share

Locations

CA (1)