Recruiting

tACS

Sponsor:

The Cleveland Clinic

Code:

NCT07791966

Conditions

Complex Regional Pain Syndrome (CRPS)

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

transcranial alternating current stimulation (tACS)

transcranial alternating current stimulation (tACS)

Study Details

Brief summary:

Pain avoidance helps with survival. However, chronic pain patients often avoid valued life activities fearing onset or exacerbation of pain. Hence, pain avoidance no longer protects, but reduces quality of life. The goal of this clinical trial is to learn if non-invasive brain stimulation technique called transcranial alternating current stimulation (tACS) impact pain avoidance behavior in chronic pain patients. tACS is a way to gently stimulate the brain using a small, portable device. It sends an extremely weak, continuous alternating current through the scalp. Participants will either get real tACS or a fake (sham) version. Real tACS will stimulate the brain in the alpha frequency (8-12 Hz) which has been found to influence pain avoidance behavior, whereas sham tACS will stimulate the brain in a different frequency that is not known to influence avoidance behavior. The main questions it aims to answer are:

Does tACS alter the way chronic pain patients confront pain in terms of avoidance behavior? How does tACS impact brain signals related to pain avoidance behavior?

Participants will:

1. fill out self-administered questionnaires asking about their medication use, personality and temperament, mood, including anxiety and depression, current pain level, and any disability you have due to your pain.
2. perform of a pain avoidance task before, during and after 'real' tACS or 'sham' tACS. They may also be asked to stay quiet before, during and after tACS. During this period, we will scan the brain using a neuroimaging device called Magnetoencephalography (MEG). Additionally, Electroencephalography (EEG) brain signals will also be collected using electrodes affixed to the scalp. We may also measure Skin conductance response (SCR) and electrocardiography (EKG) using electrodes affixed to the skin.
3. also get a T1 MRI if they do not have an implanted SCS, DRG, intrathecal pump, or other similar device that are not MRI compatible.

Conditions

Complex Regional Pain Syndrome (CRPS)

Study ID

NCT07791966

Start date

Oct 1, 2026

Status verified date

Aug, 2026

Completion date

Dec, 2028

Anticipated

Primary completion date

Aug 31, 2028

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • Age 18 years or older
  • Diagnosed with Complex Regional Pain Syndrome (CRPS) Type I or II, based on Budapest criteria
  • 6 months or more of medically refractory severe pain
  • Average daily pain for past 30 days >= 5 on 0-10 scale
  • Presence of allodynia and/or hyperalgesia
  • Lower extremity CRPS: bilateral or unilateral pain
  • Not concurrently treated with neurostimulation therapies such as spinal cord stimulators (SCS)
  • Absence of co-occurring severe psychiatric disorders (PHQ-9<19 and/or GAD-7<14)

Exclusion Criteria:

  • Age under 18 years, pregnant women of any age
  • Any co-occurring pain diagnosis that might confound with allodynia/hyperalgesia resulting from CRPS reflecting a malfunction in sensory processing within the CNS.
  • Less than six months of medically refractory pain
  • Average daily pain for past 30 days <5 on 0-10 scale
  • Absence of allodynia and/or hyperalgesia
  • Concurrent neurostimulation therapies such as SCS
  • Severe disorders or conditions (e.g., cardiovascular, liver issues), terminal illness
  • PHQ-9>19 and/or GAD-7>14 (severe depression/anxiety)

Study Design

Enrollment

30 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: alpha frequency tACS

active comparator: gamma frequency tACS

Interventions

transcranial alternating current stimulation (tACS)

Real tACS will stimulate the brain in the individual alpha frequency (8-12 Hz) measured from baseline MEG

transcranial alternating current stimulation (tACS)

active control tACS will stimulate the brain at 40Hz

Primary outcome measure

  • magnitude of alpha frequency band power [ Time Frame: Periprocedural ]

Central Contacts and Locations

Central contacts

Raghavan Gopalakrishnan

2164459322gopalar@ccf.org

Locations

Cleveland Clinic

Recruiting

Cleveland, Ohio, United States, 44195

Contacts

Raghavan Gopalakrishnan

800-223-2273gopalar@ccf.org

More Information

Sponsor

The Cleveland Clinic

Last update posted

Aug 28, 2026

Last verified

Aug, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by The Cleveland Clinic on 2026-08-28.