Experimental Pain in Healthy Human SubjectsNCT07325058
Tonic Pain and Transauricular Vagal Nerve Stimulation
A study testing taVNS and Earlobe Stimulation in people with Experimental Pain in Healthy Human Subjects, run by Aalborg University at 1 site in Denmark.
Trial summary
This study aims to explore the effect of burst-taVNS (electric stimulation of the concha cymba) on tonic (capsaicin-induced skin pain) and acute (pressure pain sensitivity) experimental pain and cardioception. Primary outcomes include pain intensity. Read more about this study
- Who is it for?
- Ages 16 to 60 yearsHealthy volunteers can take part
- Conditions the study is for
- Experimental Pain in Healthy Human Subjects
- What is being tested?
- taVNS and Earlobe Stimulation
- Type of treatment
- Medical device
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 36 participants
- Where
- 1 siteDenmark
- Study dates
- 18 Dec 2025to Apr 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 16 to 60 years
- All sexes
- Healthy volunteers accepted
- Child, Adult
Who may be able to join
- Healthy
- Speak and understand English
- 18-60 years old.
Who cannot join
- Pregnant and/or breastfeeding
- Regular use of cannabis, opioids or other drugs
- Current or previous neurologic, musculoskeletal, mental, or other illnesses (e.g., brain or spinal cord injuries, degenerative neurological disorders, major depression, cardiovascular disease, chronic lung disease, etc.)
- Current regular (once or more a week) use of analgesic medication or other medication which may affect the trial (including paracetamol and NSAIDs)
- Recent history of acute pain particularly in the lower limbs
- Abnormally disrupted sleep in 24 hours preceding experiment
Show all 9Show fewer
- Contraindications to electric stimulation application (history of epilepsy, metal implants in head or jaw, etc.)
- Lack of ability to cooperate
- Contraindications for capsaicin including an intolerance chili consumption and burns or wounds to the application site.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Denmark1 site, 1 recruiting
- Recruiting
Center For Neuroplasticity and Pain
Aalborg, 9000
Laura M.R. De Herde, 004593889540, lauramrdh@hst.aau.dk
About this study
Official title: Exploration of the Effect, and Their Duration, of Different Frequency Transcutaneous Auricular Vagal Nerve Stimulation on Sensory Perception.
This study aims to explore the effect of burst-taVNS (electric stimulation of the concha cymba) on tonic (capsaicin-induced skin pain) and acute (pressure pain sensitivity) experimental pain and cardioception. Primary outcomes include pain intensity. Secondary outcomes include sensory thresholds, resting heart rate (EKG), pupillary measurements and conditioned pain modulation.
Read the detailed description
Across 3 visits, each lasting around 2.5hours, burst-taVNS (electrical stimulation of the concha cymba) will be compared to active-control (electrircal stimulation of the earlobe) and sham (no current) stimulation, two gold-standard controls. Assessments of outcomes will occur before capsaicin application and before, twice during and after electrical ear stimulation.
- Being tested
- taVNS, Earlobe Stimulation, Sham (No Treatment)
- Keywords
- cross-over, taVNS
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
taVNSDevice
Two-headed ball-point electrode which is placed in the concha cymba.
Earlobe StimulationDevice
Circular urface adhering electrodes will be attached to either facet of the earlobe.
Sham (No Treatment)Device
Circular surface adhesive electrodes will be placed on either facet of the earlobe. No current will pass through the electrodes.
| Study group | Role | What they receive |
|---|---|---|
| taVNS | Experimental | Bursts of 25Hz occuring for 3.4sec every 29.4sec for 40min. Receives: Device: taVNS |
| Earlobe Stimulation | Active comparator | Bursts of 25Hz occuring for 3.4sec every 29.4sec for 40min. Receives: Device: Earlobe Stimulation |
| Sham | Placebo comparator | No stimulation. Receives: Device: Sham (No Treatment) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Pain Intensity
Capaisin is a topically administered tonic pain model. Stemming from its chilly-origin, pain induced ressembels heat/light burning sensation which increases within 20minute of application to the forearm, before it plateaus. Associated pain can be stopped immediately by applying ice/cold water. Participants will be asked to rate (using a scale from 0 denoting no pain, to 10 denoting maximal pain) the intensity of the pain in 5 min time intervals.
Measured: From when capsaicin is applied to the end of the experiment in 5 min intervals.
Secondary outcomes (6)
Pressure Pain Detection Threshold
Using the computerized pressure pain algometer tool (Nocitech, Aalborg, Denmark), cuffs placed on the calves of participants wll inflate at a consistent rate. Participants are instructed to rate the pain experiences using a visual analogue scale (VAS) and to press a button when the pain becomes intolerable. The VAS ranges from 0 denoting no pain, to 10 denoting maximal pain. Pain detection, namely the kPa where the VAS is at 1cm, and the pain tolerance, namely the kPa when the deflation-button is pressed, will be acquired.
Measured: Before Capsaicin application and at 3 time intervals from when the ear stimulation (taVNS, Active Control or Sham) is applied: before, as the stimulation starts and halfway during (at min 20).
Conditioned Pain Modulation Effect
Using the computerized pressure pain algometer tool (Nocitech, Aalborg, Denmark), cuffs placed on the calves of participants wll inflate at a consistent rate. Whilst participants have a constant pressure applied to their non-dominant leg, they are instructed to rate the pain experienced on the dominant leg as the cuff slowly inflates using a visual analogue scale (VAS) and to press a button when the pain becomes intolerable. The VAS ranges from 0 denoting no pain, to 10 denoting maximal pain. Conditioned pain detection, namely the kPa where the VAS is at 1cm, will be acquired.
Measured: Before Capsaicin application and at 3 time intervals from when the ear stimulation (taVNS, Active Control or Sham) is applied: before, as the stimulation starts and halfway during (at min 20).
Pressure Pain Perception
Trapezius pressure pain perception will be acquired using a handheld pressure algometer (Somedic, Solna, Sweden). Perpendicular to the musle and halfway between the acrominion and the processus spinous vertebrae, the 1cm2 probe will be applied at a constant rate. When particpants first feel pressure pain, they will respond with a button-press.
Measured: Before Capsaicin application and at 3 time intervals from when the ear stimulation (taVNS, Active Control or Sham) is applied: before, as the stimulation starts and halfway during (at min 20).
Pupillary Light Reflex
Using the Neurolight, per pupil, a 3s light reflex will be acquired. This refers to the reflex following the exposure to a light flash.
Measured: Before Capsaicin application and at 3 time intervals from when the ear stimulation (taVNS, Active Control or Sham) is applied: before, as the stimulation starts and halfway during (at min 20).
Electrocardiography
Using a 3-lead system (reference electrode on the clavicle, whilst the other two leads reside on the sternum and V4), resting state electrocardiography will be acquired.
Measured: Before Capsaicin application and at 3 time intervals from when the ear stimulation (taVNS, Active Control or Sham) is applied: before, as the stimulation starts and halfway during (at min 20).
Cardioception Accuracy
The ability to perceive your heart beats is described as cardioception. One means by which to assess this ability is the 'heartbeat couting task'. Herein, using a queue, participants are tasked to count their heartbeats in 3 undislosed and randomized durations (25, 35 and 35s). This value is then compare to the actual number of beats during each time interval, which is acquired via electrocardiography.
Measured: Before Capsaicin application and at 3 time intervals from when the ear stimulation (taVNS, Active Control or Sham) is applied: before, as the stimulation starts and halfway during (at min 20).
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Jan 2026
- Study start18 Dec 2025
- Primary completionMar 2026 (estimated)
- Study completionApr 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Experimental Pain in Healthy Human SubjectsStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- Burst-taVNS, active-control (electrical stimulation of the earlobe) or sham will be administred to the participant on one of the three visits. Order of stimulation condition will be randomly selected and counter-balanced across participants (minding sex at birth).
- Masking
- Triple blind
- Who is masked
- Participant, Investigator, Outcomes assessor
- Enrolment
- 36 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Aalborg University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Laura De Herde, Aalborg University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07325058
- Sponsor's protocol ID
- N-20230022-5
- Status last verified
- Dec 2025
- First submitted
- 16 Dec 2025
- Last updated
- 8 Jan 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided: There is only one researcher working on this project. Information will not be shared.
Study at a glance
From the registry record, last updated by the sponsor on 8 Jan 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Exploration of the Effect, and Their Duration, of Different Frequency Transcutaneous Auricular Vagal Nerve Stimulation on Sensory Perception.
- ClinicalTrials.gov ID
- NCT07325058
- Acronym / sponsor ID
- N-20230022-5
- Keywords
- cross-over, taVNS
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 36 participants (estimated)
- Lead sponsor
- Aalborg UniversityUniversity, hospital or other
- Study start
- 18 Dec 2025 (actual)
- Primary completion
- Mar 2026 (estimated)
- Study completion
- Apr 2026 (estimated)
- First posted
- 8 Jan 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study aims to explore the effect of burst-taVNS (electric stimulation of the concha cymba) on tonic (capsaicin-induced skin pain) and acute (pressure pain sensitivity) experimental pain and cardioception. Primary outcomes include pain intensity. Secondary outcomes include sensory thresholds, resting heart rate (EKG), pupillary measurements and conditioned pain modulation.
Detailed description
Across 3 visits, each lasting around 2.5hours, burst-taVNS (electrical stimulation of the concha cymba) will be compared to active-control (electrircal stimulation of the earlobe) and sham (no current) stimulation, two gold-standard controls. Assessments of outcomes will occur before capsaicin application and before, twice during and after electrical ear stimulation.
Study design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Triple blind (participant, investigator, outcomes assessor)
- Number of arms
- 3
- Model description
- Burst-taVNS, active-control (electrical stimulation of the earlobe) or sham will be administred to the participant on one of the three visits. Order of stimulation condition will be randomly selected and counter-balanced across participants (minding sex at birth).
| Arm | Type | Receives |
|---|---|---|
| taVNS | Experimental | Device: taVNSBursts of 25Hz occuring for 3.4sec every 29.4sec for 40min. |
| Earlobe Stimulation | Active comparator | Device: Earlobe StimulationBursts of 25Hz occuring for 3.4sec every 29.4sec for 40min. |
| Sham | Placebo comparator | Device: Sham (No Treatment)No stimulation. |
Who may qualify
- Ages
- 16 to 60 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Child, Adult
Key inclusion criteria (3 listed)
- Healthy
- Speak and understand English
- 18-60 years old.
Key exclusion criteria (9 listed)
- Pregnant and/or breastfeeding
- Regular use of cannabis, opioids or other drugs
- Current or previous neurologic, musculoskeletal, mental, or other illnesses (e.g., brain or spinal cord injuries, degenerative neurological disorders, major depression, cardiovascular disease, chronic lung disease, etc.)
- Current regular (once or more a week) use of analgesic medication or other medication which may affect the trial (including paracetamol and NSAIDs)
- Recent history of acute pain particularly in the lower limbs
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| taVNSTwo-headed ball-point electrode which is placed in the concha cymba. | Device | taVNS |
| Earlobe StimulationCircular urface adhering electrodes will be attached to either facet of the earlobe. | Device | Earlobe Stimulation |
| Sham (No Treatment)Circular surface adhesive electrodes will be placed on either facet of the earlobe. No current will pass through the electrodes. | Device | Sham |
Primary outcome
Pain Intensity
Time frame: From when capsaicin is applied to the end of the experiment in 5 min intervals.
Capaisin is a topically administered tonic pain model. Stemming from its chilly-origin, pain induced ressembels heat/light burning sensation which increases within 20minute of application to the forearm, before it plateaus. Associated pain can be stopped immediately by applying ice/cold water. Participants will be asked to rate (using a scale from 0 denoting no pain, to 10 denoting maximal pain) the intensity of the pain in 5 min time intervals.
6 secondary outcomes
Pressure Pain Detection Threshold
Time frame: Before Capsaicin application and at 3 time intervals from when the ear stimulation (taVNS, Active Control or Sham) is applied: before, as the stimulation starts and halfway during (at min 20).
Conditioned Pain Modulation Effect
Time frame: Before Capsaicin application and at 3 time intervals from when the ear stimulation (taVNS, Active Control or Sham) is applied: before, as the stimulation starts and halfway during (at min 20).
Pressure Pain Perception
Time frame: Before Capsaicin application and at 3 time intervals from when the ear stimulation (taVNS, Active Control or Sham) is applied: before, as the stimulation starts and halfway during (at min 20).
Pupillary Light Reflex
Time frame: Before Capsaicin application and at 3 time intervals from when the ear stimulation (taVNS, Active Control or Sham) is applied: before, as the stimulation starts and halfway during (at min 20).
Electrocardiography
Time frame: Before Capsaicin application and at 3 time intervals from when the ear stimulation (taVNS, Active Control or Sham) is applied: before, as the stimulation starts and halfway during (at min 20).
Cardioception Accuracy
Time frame: Before Capsaicin application and at 3 time intervals from when the ear stimulation (taVNS, Active Control or Sham) is applied: before, as the stimulation starts and halfway during (at min 20).
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 8 Jan 2026.
- Individual participant dataSharing planned: Undecided. There is only one researcher working on this project. Information will not be shared.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing taVNS and Earlobe Stimulation in people with Experimental Pain in Healthy Human Subjects, run by Aalborg University at 1 site in Denmark.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 8 Jan 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Denmark. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Each site lists its own contact: choose the nearest one under Trial locations. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Pain Intensity (time frame: From when capsaicin is applied to the end of the experiment in 5 min intervals.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 8 Jan 2026.