Neural Correlates of Hypoalgesia Driven by Observation

Summary

Placebo effects held an ambivalent place in health care for at least two centuries. On the one hand, placebos are traditionally used as controls in clinical trials to correct for biases and the placebo response is viewed as an effect to be factored out in order to isolate and accurately measure the effects of the treatment. On the other hand, there is scientific evidence that placebo effects represent fascinating psychoneurobiological events involving the contribution of distinct central nervous as well as peripheral physiological mechanisms that influence pain perception and clinical pain symptoms and substantially modulate the response to pain therapeutics. Therefore, placebo effects have shifted from being a challenge for clinical trials to a resource to trigger the reduction of pain based on endogenous mechanisms that can be activated in the brain to promote hypolagesia, self-healing, and well-being. This is relevant in acute pain settings given that chronic opioid users die within approximately 2.5 years of being prescribed their first opioid medication to treat acute pain.

The overall hypothesis is that observational learning influences neural pain modulation and cognition systems, including processes associated with mentalizing (the ability to cognitively understand mental states of others), empathy (the ability to share an emotional experience), and expectancy (the anticipation of a benefit). The objective is to determine the brain mechanisms of observationally-induced analgesia using brain mapping approaches that target changes in blood oxygenation and oscillatory activity in the brain, thus enabling investigators to draw inferences about the localization and extent of neurobiological activation underlying hypoalgesia driven by observation. Therefore, the investigators designed innovative experiments using pharmacological fMRI, EEG, and combined EEG-fMRI measurements.

Conditions

• Pain
• Virtual Reality
• Placebo

Interventions

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.

Sponsors & Collaborators

• University of Maryland, Baltimore

  lead OTHER

Principal Investigators

• Luana Colloca, MD/PhD/MS · University of Maryland Baltimore School of Nursing

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

TRIPLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

65 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2021-11-01

Primary Completion

2025-12-31

Completion

2025-12-31

FDA Drug

Yes

Countries

• United States

Study Locations