Clinical Trial Finder

Inclusion Criteria:

• - Age (18-88 years) - English speaker (written and spoken) - Temporal Mandibular Disorder (TMD) for at least 3 months.

Exclusion Criteria:

• - Present or past degenerative neuromuscular disease.

• - Cardiovascular, neurological diseases, pulmonary abnormalities, kidney disease, liver disease, history of cancer within past 3 years.

• - Cervical pain other than TMD related (e.g. stenosis, radiculopathy) - Any personal (or family first degree) history of mania, schizophrenia, or other psychoses.

• - Severe psychiatric condition (e.g., schizophrenia, bipolar disorders, autism) leading to hospitalization within the last 3 years.

• - Use of antidepressants, ADHD medication, non-over-the-counter painkillers, methadone, benzodiazepines, barbiturates, and/or narcotics during the past 3 months.

• - Lifetime alcohol/drug dependence or alcohol/drug abuse in the past 3 months.

• - Pregnancy or breastfeeding.

• - Color-blindness.

• - Pain in jaw or temple in last 3 months due to toothache or infection.

• - Any facial trauma that has occurred in the last 6 weeks.

• - History of severe facial trauma in the last 3 months.

• - Impaired or uncorrected hearing.

• - Conditions that would interfere with the VR mask placement (e.g. trauma, burn, infection) - Known history of severe motion sickness.

• - High blood pressure or symptomatic low blood pressure.

• - History of fainting.

• - History of angioedema.

- Failed drug test (testing for opiates, cocaine, methamphetamines, amphetamines, and THC)

Virtual reality (VR) has been seen as an intervention for alleviating clinical chronic (and acute) pain. An approach to pain management utilizing VR presents opportunities for reducing pain and suffering by using immersive, aesthetic, and multisensory stimulation. Investigator will analyze the behavioral and neural mechanisms of active VR against sham VR as two methods that investigate descending pain modulation. Thus, the central hypothesis is that those who respond to placebos will likely respond to active VR. If VR-induced analgesia depends upon the release of endogenous opioids. In this project, the investigators will determine the effects of VR at the neural and clinical levels directly for TMD participants, inviting participants from an existing Colloca Lab-based cohort phenotyped for diagnosis, grade, and low/high impact pain profiles and prospective TMD participants in collaboration with Johns Hopkins University. These participants have agreed to be recontacted for further research. Investigator will determine the role of the opioid tone (AIM1). In Aim 1, the investigators will determine the role of the endogenous opioid tone for VR-induced hypoalgesia in TMD participants using VR, tonic painful stimuli, and naloxone given intranasally with established mu-opioid receptor occupancy to determine how the opioid tone shapes VR-induced hypoalgesia.

Arms

Active Comparator: Naloxone

NARCAN® Naloxone Nasal Spray will be used to determine how the opioid tone shapes VR-induced hypoalgesia. Participants will be stratified for sex and then randomized to naloxone (The dose of naloxone will be 4 mg, so 0.1 mL of 40 mg/ml naloxone solution given intranasally) or saline (0.1 mL 0.9% sodium chloride intranasally), respectively. Investigators, staff, and participants will be blinded to the treatment options.

Sham Comparator: Saline

Saline group, where participants will be given saline solution (4mg) via an identical spray device. Participants will be stratified for sex and then randomized to saline arm (The dose of saline will be (0.1 mL 0.9% sodium chloride intranasally), respectively. Investigators, staff, and participants will be blinded to the treatment options.

Other: Natural History

Natural history group, where participants will not be given any drugs. Participants will be stratified for sex and then randomized to the Natural History group.

Interventions

Behavioral: - Active Virtual Reality

Participants will be assigned to an immersive VR environment.

Behavioral: - sham Virtual Reality

Participants will be assigned to a sham VR environment without the immersive experience.

Other: - No Intervention

Participants will experience tonic pain tolerance tests without exposure to any environments.

Drug: - Naloxone

4mg of Naloxone will be administered (0.1 mL of 40 mg/ml naloxone solution given intranasally). A random allocation sequence will be independently generated by the UM Pharmacy. The Principal investigator will call for each experiment.

Other: - Saline

Intranasal Normal Saline (0.1 mL 0.9% sodium chloride) will be administered shortly before beginning the fMRI experiment. A random allocation sequence will be independently generated by the UM Pharmacy. The Principal investigator will call for each experiment.

Other: - Natural history

Participants will not be provided Naloxone or Saline.