FibromyalgiaLight BulbNCT07825792
Light Bulb Stimuli to Reduce Chronic Pain
A study testing S-Cone Stimulating Chromatic Light and Equal-Energy White Light in people with Fibromyalgia and Musculoskeletal Pain, run by University of North Carolina, Chapel Hill at 1 site in United States.
Trial summary
This pilot randomized, double-blind, crossover clinical trial will evaluate the feasibility and preliminary efficacy of chromatic (colored) light exposure for reducing pain severity and pain sensitivity in adults with fibromyalgia or chronic widespread pain and fatigue. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Fibromyalgia, Musculoskeletal Pain
- What is being tested?
- S-Cone Stimulating Chromatic Light and Equal-Energy White Light
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 40 participants
- Where
- 1 siteUnited States
- Study dates
- 21 Sep 2026to 1 Jan 2028
- 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 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Adults ≥ 18 years of age.
- Individuals who have been diagnosed with fibromyalgia or suffer from chronic widespread pain and fatigue.
- An average pain severity ≥4 on the 0-10 NRS over the month prior to enrollment.
- Pain symptoms present for 3 months or longer.
- Pain must be present in 4 out of 5 body regions.
- A score of ≥7 on the Widespread pain index (WPI) and ≥5 on the symptom severity scale (SSS), or 4-6 on the WPI and ≥9 on the SSS in the 2016 Fibromyalgia Questionnaire.
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- Willingness to adjust light levels in home environment so that the illumination (measured in lux) provided by the light bulbs is twice the ambient room illumination (also measured in lux).
- Willingness to use study lightbulbs for 2 consecutive hours a day for 7 consecutive days according to study specifications for both conditions (total of 14 days using lightbulbs)
- Alert and oriented, and able to provide informed consent
- Ability to read and speak English to complete validated questionnaires.
Who cannot join
- Vision disorders or conditions resulting in severe vision impairment or blindness
- Individuals with self-report of color blindness, uveitis or cataracts.
- Prisoner Status
- Pregnancy
- History of photosensitivity or sensitivity to scintillating (mildly flickering) light.
- History of seizure disorder.
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- Individuals living in households with people who have a history of seizure disorders.
- Analgesic treatment plan changes anticipated in the next 3 months (surgery, analgesic medication changes, injections, pain procedures, etc.).
- Other history or condition that would, in the investigator's judgment, indicate that the individual would highly likely be non-compliant with the study or unsuitable for the study
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site
University of North Carolina at Chapel Hill
Chapel Hill, North Carolina, 27514
Matt Mauck, MD, PhD, 919-966-5136, matt_mauck@med.unc.edu
About this study
Official title: Chromatic Retinal Stimulation to Reduce Chronic Pain and Pain Sensitivity Using Light Bulbs: A Pilot Randomized Crossover Trial
This pilot randomized, double-blind, crossover clinical trial will evaluate the feasibility and preliminary efficacy of chromatic (colored) light exposure for reducing pain severity and pain sensitivity in adults with fibromyalgia or chronic widespread pain and fatigue. Participants will complete daily symptom surveys throughout the study and undergo patient-reported outcome assessments and quantitative sensory testing at multiple timepoints.
Participants will be randomized to receive either S-cone stimulating chromatic light or equal-energy white light for 2 hours daily over a 7-day treatment period. Following a 1-week washout, participants will cross over to the alternate condition. Outcomes will examine feasibility, changes in pain severity, pain interference, and measures of pain sensitivity. Total study duration is approximately 35 days.
Read the detailed description
This pilot, randomized, double-blind, crossover clinical trial is designed to evaluate the feasibility of administering a chromatic light intervention and to explore its effects on pain severity and pain sensitivity in adults with fibromyalgia or chronic widespread pain and fatigue.
Following informed consent and enrollment, baseline assessments will be performed which will include demographic and health questionnaires, validated patient-reported outcome measures, and quantitative sensory testing (QST), including assessments of conditioned pain modulation, temporal summation, and pressure pain threshold.
Participants will then be randomly assigned to one of two treatment sequences:
S-cone stimulating chromatic light during Treatment Period 1 followed by equal-energy white light during Treatment Period 2.
Equal-energy white light during Treatment Period 1 followed by S-cone stimulating chromatic light during Treatment Period 2.
The study utilizes commercially available "TUO" programmable light bulbs that deliver pre-programmed light spectra. Participants will receive study equipment, including five programmed light bulbs, portable lamps, and an illuminometer to verify that the intervention light intensity is at least twice the ambient room illumination. Participants will use the assigned light condition for 2 hours daily, ideally between 5:00 a.m. and 10:00 a.m., for 7 consecutive days while engaging in normal daily activities.
At the end of the first treatment period, participants will return for repeat patient-reported outcome assessments and quantitative sensory testing. Participants will then complete a 1-week washout period during which no light intervention is administered, although daily symptom surveys will continue. Following washout, participants will cross over to the alternate light condition and complete a second 7-day treatment period identical to the first.
After completion of the second treatment period, participants will undergo final intervention assessments, return study equipment, and enter a 1-week follow-up period with continued daily symptom monitoring. At the final study visit, participants will complete follow-up questionnaires and optional quantitative sensory testing.
The primary objective is to determine the feasibility and acceptability of delivering chromatic light therapy for 2 hours daily across two treatment periods. Secondary objectives include evaluating whether chromatic light exposure reduces chronic pain severity and pain sensitivity to a greater extent than an equal-energy white light control condition. Approximately 40 participants will be enrolled, and total participation time will be approximately 35 days. Risks associated with the intervention are expected to be minimal and primarily include potential light sensitivity or discomfort and standard risks related to data confidentiality.
- Conditions
- Fibromyalgia, Musculoskeletal Pain
- Being tested
- S-Cone Stimulating Chromatic Light, Equal-Energy White Light
- Keywords
- Fibromyalgia, Musculoskeletal Pain, Analgesia
- Medical subject headings
- Fibromyalgia, Musculoskeletal Pain, Agnosia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
S-Cone Stimulating Chromatic LightDevice
Participants receive exposure to S-cone stimulating chromatic light delivered via programmed TUO light bulbs. Light is administered for 2 hours daily for 7 consecutive days, ideally between 5:00 a.m. and 10:00 a.m.. Participants use the light in their home environment while engaging in normal daily activities. Light intensity is maintained at a minimum of twice the ambient room illumination using an illuminometer provided by the study. This intervention is designed to selectively stimulate short-wavelength-sensitive (S-cone) photoreceptors.
Equal-Energy White LightDevice
Participants receive exposure to a light that appears equal-energy white that flickers along the L/M axis delivered via programmed TUO light bulbs. Light is administered for 2 hours daily for 7 consecutive days, ideally between 5:00 a.m. and 10:00 a.m. Participants use the light in their home environment while engaging in normal daily activities. Light intensity is maintained at a minimum of twice the ambient room illumination using an illuminometer provided by the study. This intervention serves as the control condition for comparison with the S-cone stimulating chromatic light intervention.
| Study group | Role | What they receive |
|---|---|---|
| S-cone stimulating chromatic light first followed by equal-energy white light | Experimental | Participants randomized to this sequence will receive S-cone stimulating chromatic light during the first treatment period, followed by equal-energy white (flickering along the L/M axis) light during the second treatment period. Each treatment period consists of 2 hours of daily light exposure for 7 consecutive days, ideally between 5:00 a.m. and 10:00 a.m., delivered using programmed "TUO" light bulbs. The two treatment periods are separated by a 1-week washout period. Participants complete daily symptom surveys, patient-reported outcome measures, and quantitative sensory testing throughout the study. Receives: Device: S-Cone Stimulating Chromatic Light; Device: Equal-Energy White Light |
| Equal-energy white light first followed by S-cone stimulating chromatic light | Experimental | Participants randomized to this sequence will receive equal-energy white light (flickering along the L/M axis) during the first treatment period, followed by S-cone stimulating chromatic light during the second treatment period. Each treatment period consists of 2 hours of daily light exposure for 7 consecutive days, ideally between 5:00 a.m. and 10:00 a.m., delivered using programmed "TUO" light bulbs. The two treatment periods are separated by a 1-week washout period. Participants complete daily symptom surveys, patient-reported outcome measures, and quantitative sensory testing throughout the study. Receives: Device: S-Cone Stimulating Chromatic Light; Device: Equal-Energy White Light |
What is being measured
The primary outcome is the main question the study is designed to answer.
Percentage of participants completing follow-up visits after each intervention period
Feasibility will be assessed by percentage of participants completing follow-up visits after each intervention period.
Measured: Throughout study participation (35 days)
Percentage of daily flash surveys completed during the two 7-day stimulation periods
Feasibility will be assessed by percentage of daily flash surveys completed during the two 7-day stimulation periods (14 eligible survey time points).
Measured: Throughout the two 7-day stimulation periods (14 eligible survey timepoints during active treatment period)
Percentage of prescribed light stimulation sessions completed based on participant self-report
Feasibility will be assessed by percentage of prescribed light stimulation sessions completed based on participant self-report.
Measured: Throughout the two 7-day stimulation periods (14 eligible survey timepoints during active treatment period)
Secondary outcomes (4)
Pain Intensity
Pain severity will be measured using an 11-point Numeric Rating Scale (NRS), where 0 represents no pain and 10 represents the worst pain imaginable. Mean pain scores following S-cone stimulating light and equal-energy white light conditions will be compared.
Measured: Baseline, post-treatment period 1 (Day 14), post-treatment period 2 (Day 28), and follow-up (Day 35)
Pressure Pain Threshold
Pressure pain threshold will be assessed using a pressure algometer applied to the trapezius muscle. Outcomes will be recorded in kilograms of force per square centimeter (kgf/cm^2). Higher values indicate greater pain tolerance and reduced pain sensitivity.
Measured: Baseline, post-treatment period 1 (Day 14), and post-treatment period 2 (Day 28).
Temporal Summation
Temporal summation will be assessed using a 256 millinewton (mN) pinprick stimulator. Pain intensity ratings following a single stimulus and a train of 10 repetitive stimuli will be used to quantify central pain facilitation. Lower temporal summation values indicate reduced pain sensitivity.
Measured: Baseline, post-treatment period 1 (Day 14), and post-treatment period 2 (Day 28).
Conditioned Pain Modulation
Conditioned pain modulation will be calculated as the difference in pressure pain threshold measured before and after a conditioning cold-water stimulus. Greater increases in pressure pain threshold following conditioning indicate more effective endogenous pain inhibition.
Measured: Baseline, post-treatment period 1 (Day 14), and post-treatment period 2 (Day 28).
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted17 Sep 2026
- Study start21 Sep 2026 (estimated)
- Primary completion1 Jan 2028 (estimated)
- Study completion1 Jan 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for FibromyalgiaStudies 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
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Triple blind
- Who is masked
- Participant, Investigator, Outcomes assessor
- Enrolment
- 40 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of North Carolina, Chapel Hill
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Matt Mauck, MD, PhD, Principal investigator, UNC Chapel Hill School of Medicine
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07825792
- Sponsor's protocol ID
- 24-1180
- Acronym
- Light Bulb
- Status last verified
- Sep 2026
- First submitted
- 11 Sep 2026
- Last updated
- 17 Sep 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 17 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Chromatic Retinal Stimulation to Reduce Chronic Pain and Pain Sensitivity Using Light Bulbs: A Pilot Randomized Crossover Trial
- ClinicalTrials.gov ID
- NCT07825792
- Acronym / sponsor ID
- Light Bulb / 24-1180
- Conditions
- Fibromyalgia, Musculoskeletal Pain
- Keywords
- Fibromyalgia, Musculoskeletal Pain, Analgesia
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 40 participants (estimated)
- Lead sponsor
- University of North Carolina, Chapel HillUniversity, hospital or other
- Study start
- 21 Sep 2026 (estimated)
- Primary completion
- 1 Jan 2028 (estimated)
- Study completion
- 1 Jan 2028 (estimated)
- First posted
- 17 Sep 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 pilot randomized, double-blind, crossover clinical trial will evaluate the feasibility and preliminary efficacy of chromatic (colored) light exposure for reducing pain severity and pain sensitivity in adults with fibromyalgia or chronic widespread pain and fatigue. Participants will complete daily symptom surveys throughout the study and undergo patient-reported outcome assessments and quantitative sensory testing at multiple timepoints.
Participants will be randomized to receive either S-cone stimulating chromatic light or equal-energy white light for 2 hours daily over a 7-day treatment period. Following a 1-week washout, participants will cross over to the alternate condition. Outcomes will examine feasibility, changes in pain severity, pain interference, and measures of pain sensitivity. Total study duration is approximately 35 days.
Detailed description
This pilot, randomized, double-blind, crossover clinical trial is designed to evaluate the feasibility of administering a chromatic light intervention and to explore its effects on pain severity and pain sensitivity in adults with fibromyalgia or chronic widespread pain and fatigue.
Following informed consent and enrollment, baseline assessments will be performed which will include demographic and health questionnaires, validated patient-reported outcome measures, and quantitative sensory testing (QST), including assessments of conditioned pain modulation, temporal summation, and pressure pain threshold.
Participants will then be randomly assigned to one of two treatment sequences:
S-cone stimulating chromatic light during Treatment Period 1 followed by equal-energy white light during Treatment Period 2.
Equal-energy white light during Treatment Period 1 followed by S-cone stimulating chromatic light during Treatment Period 2.
The study utilizes commercially available "TUO" programmable light bulbs that deliver pre-programmed light spectra. Participants will receive study equipment, including five programmed light bulbs, portable lamps, and an illuminometer to verify that the intervention light intensity is at least twice the ambient room illumination. Participants will use the assigned light condition for 2 hours daily, ideally between 5:00 a.m. and 10:00 a.m., for 7 consecutive days while engaging in normal daily activities.
At the end of the first treatment period, participants will return for repeat patient-reported outcome assessments and quantitative sensory testing. Participants will then complete a 1-week washout period during which no light intervention is administered, although daily symptom surveys will continue. Following washout, participants will cross over to the alternate light condition and complete a second 7-day treatment period identical to the first.
After completion of the second treatment period, participants will undergo final intervention assessments, return study equipment, and enter a 1-week follow-up period with continued daily symptom monitoring. At the final study visit, participants will complete follow-up questionnaires and optional quantitative sensory testing.
The primary objective is to determine the feasibility and acceptability of delivering chromatic light therapy for 2 hours daily across two treatment periods. Secondary objectives include evaluating whether chromatic light exposure reduces chronic pain severity and pain sensitivity to a greater extent than an equal-energy white light control condition. Approximately 40 participants will be enrolled, and total participation time will be approximately 35 days. Risks associated with the intervention are expected to be minimal and primarily include potential light sensitivity or discomfort and standard risks related to data confidentiality.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Triple blind (participant, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| S-cone stimulating chromatic light first followed by equal-energy white light | Experimental | Device: S-Cone Stimulating Chromatic Light, Device: Equal-Energy White LightParticipants randomized to this sequence will receive S-cone stimulating chromatic light during the first treatment period, followed by equal-energy white (flickering along the L/M axis) light during the second treatment period. Each treatment period consists of 2 hours of daily light exposure for 7 consecutive days, ideally between 5:00 a.m. and 10:00 a.m., delivered using programmed "TUO" light bulbs. The two treatment periods are separated by a 1-week washout period. Participants complete daily symptom surveys, patient-reported outcome measures, and quantitative sensory testing throughout the study. |
| Equal-energy white light first followed by S-cone stimulating chromatic light | Experimental | Device: S-Cone Stimulating Chromatic Light, Device: Equal-Energy White LightParticipants randomized to this sequence will receive equal-energy white light (flickering along the L/M axis) during the first treatment period, followed by S-cone stimulating chromatic light during the second treatment period. Each treatment period consists of 2 hours of daily light exposure for 7 consecutive days, ideally between 5:00 a.m. and 10:00 a.m., delivered using programmed "TUO" light bulbs. The two treatment periods are separated by a 1-week washout period. Participants complete daily symptom surveys, patient-reported outcome measures, and quantitative sensory testing throughout the study. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (10 listed)
- Adults ≥ 18 years of age.
- Individuals who have been diagnosed with fibromyalgia or suffer from chronic widespread pain and fatigue.
- An average pain severity ≥4 on the 0-10 NRS over the month prior to enrollment.
- Pain symptoms present for 3 months or longer.
- Pain must be present in 4 out of 5 body regions.
Key exclusion criteria (9 listed)
- Vision disorders or conditions resulting in severe vision impairment or blindness
- Individuals with self-report of color blindness, uveitis or cataracts.
- Prisoner Status
- Pregnancy
- History of photosensitivity or sensitivity to scintillating (mildly flickering) light.
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 |
|---|---|---|
| S-Cone Stimulating Chromatic LightParticipants receive exposure to S-cone stimulating chromatic light delivered via programmed TUO light bulbs. Light is administered for 2 hours daily for 7 consecutive days, ideally between 5:00 a.m. and 10:00 a.m.. Participants use the light in their home environment while engaging in normal daily activities. Light intensity is maintained at a minimum of twice the ambient room illumination using an illuminometer provided by the study. This intervention is designed to selectively stimulate short-wavelength-sensitive (S-cone) photoreceptors. | Device | Equal-energy white light first followed by S-cone stimulating chromatic light, S-cone stimulating chromatic light first followed by equal-energy white light |
| Equal-Energy White LightParticipants receive exposure to a light that appears equal-energy white that flickers along the L/M axis delivered via programmed TUO light bulbs. Light is administered for 2 hours daily for 7 consecutive days, ideally between 5:00 a.m. and 10:00 a.m. Participants use the light in their home environment while engaging in normal daily activities. Light intensity is maintained at a minimum of twice the ambient room illumination using an illuminometer provided by the study. This intervention serves as the control condition for comparison with the S-cone stimulating chromatic light intervention. | Device | Equal-energy white light first followed by S-cone stimulating chromatic light, S-cone stimulating chromatic light first followed by equal-energy white light |
Primary outcome
Percentage of participants completing follow-up visits after each intervention period
Time frame: Throughout study participation (35 days)
Feasibility will be assessed by percentage of participants completing follow-up visits after each intervention period.
Percentage of daily flash surveys completed during the two 7-day stimulation periods
Time frame: Throughout the two 7-day stimulation periods (14 eligible survey timepoints during active treatment period)
Feasibility will be assessed by percentage of daily flash surveys completed during the two 7-day stimulation periods (14 eligible survey time points).
Percentage of prescribed light stimulation sessions completed based on participant self-report
Time frame: Throughout the two 7-day stimulation periods (14 eligible survey timepoints during active treatment period)
Feasibility will be assessed by percentage of prescribed light stimulation sessions completed based on participant self-report.
4 secondary outcomes
Pain Intensity
Time frame: Baseline, post-treatment period 1 (Day 14), post-treatment period 2 (Day 28), and follow-up (Day 35)
Pressure Pain Threshold
Time frame: Baseline, post-treatment period 1 (Day 14), and post-treatment period 2 (Day 28).
Temporal Summation
Time frame: Baseline, post-treatment period 1 (Day 14), and post-treatment period 2 (Day 28).
Conditioned Pain Modulation
Time frame: Baseline, post-treatment period 1 (Day 14), and post-treatment period 2 (Day 28).
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 17 Sep 2026.
- Individual participant dataSharing planned: No
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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.
Matt Mauck, MD, PhD principal investigator
UNC Chapel Hill School of Medicine
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing S-Cone Stimulating Chromatic Light and Equal-Energy White Light in people with Fibromyalgia and Musculoskeletal Pain, run by University of North Carolina, Chapel Hill at 1 site in United States.
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 10 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: opening soon, as of the sponsor's last update on 17 Sep 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 United States. 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. 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?
Contact Matthew Mauck, MD, PhD (919-966-5136, matt_mauck@med.unc.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Percentage of participants completing follow-up visits after each intervention period (time frame: Throughout study participation (35 days)). The study lists 3 primary outcomes in all. 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 17 Sep 2026; AzTrials last refreshed its copy on 1 Nov 2026.