Vasopressin and Pain Perception in the Brain

Summary

The feeling of pain is not just a sensory experience, but is also influenced by emotions, beliefs and expectations, making pain a highly subjective experience. This is evident in clinical practice, where the behavior of the physician and the treatment context can strongly influence the pain experience of patients. Research has shown that patients' expectation that a treatment will reduce pain influences individual perception of pain, even if the treatment has no active ingredient. The expectancy-induced analgesia emerges due to a modulation of the individual pain experience of patients by an engagement of endogenous inhibitory systems in the central nervous system.

The development of expectancy-induced analgesia can be generated in several ways. The investigators have previously demonstrated that social information and observational learning (e.g. the patient observes analgesia in another person receiving a treatment) can lead to expectancy-induced analgesia and pain reduction. However, the neural mechanisms (mechanisms in the brain) of how these expectancies are acquired and the neural mechanisms of analgesia induced by observational learning are unknown.

The investigators recently established a procedure to investigate neural mechanisms of observational learning in placebo analgesia. Here the investigators propose to investigate the influence of vasopressin, a neurotransmitter that is important for social interaction, on observational learning.

The investigators will use functional magnetic resonance imaging (fMRI), a non-invasive method, to investigate neural activity in humans. Participants will either receive vasopressin or saline with a nasal spray. During fMRI scanning, participants will then undergo an observational learning phase, where the study participants will learn the experience of analgesia in another person through a video, and a testing phase, where participants will perceive painful stimulations with the same cues as the observational phase. The comparison of the vasopressin group and the saline group will allow us to investigate how vasopressin influences behavioral effects of observational learning on pain perception as well as its effect on the neural processing of observational learning.

A better understanding of how the human brain processes observationally-induced analgesia would allow us to improve the therapeutic context of pain treatments by increasing the contextual factors which help patients cope with pain.

Conditions

• Acute Pain

Interventions

DRUG

Arginine vasopressin

Intranasal vasopressin will be administered shortly before the fMRI experiment.

OTHER

Saline

Intranasal saline will serve as a placebo for participants in the Saline Arm

BEHAVIORAL

Observational learning

During the observational learning intervention, participants will learn the experience of analgesia in another person via a video. Participants will learn the analgesia nature of the placebo cream and the neutral nature of the control cream.

OTHER

fMRI data aquisition

All participants from the intranasal vasopressin and intranasal saline groups will go through a fMRI data acquisition to obtain the brain structural, brain resting-states and functional MRI scans.

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

DOUBLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

65 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2018-09-17

Primary Completion

2026-06-30

Completion

2026-12-31

FDA Drug

Yes

Countries

• United States

Study Locations