Brain Imaging and Pain: Analysis of Placebo Analgesia

Study Overview
=================
Brief Summary
-----------------
This study examines the brain activation associated with placebo pain reduction.

Detailed Description
-----------------
This study is a basic science study of the mechanisms of placebo analgesia in asymptomatic healthy individuals. Each participant receives a baseline pain testing session, followed by a conditioning paradigm that results in expectation of pain relief and conditioning. They then undergo functional magnetic resonance imaging during either placebo (conditioned analgesia) or baseline. To examine order effects and habituation, the participants also either undergo a repeated placebo or a repeated baseline. The primary dependent measures in the study are the fMRI determined regions of interest, in a network of brain areas associated with pain processing. The anticipated outcome of the study is the alteration of network connectivity between sensory, affective, evaluative areas of the brain associated with placebo. Because this is not a traditional clinical trial, there are not traditional efficacy criteria, rather the outcomes are changes in brain function from manipulations of patient expectation and classical conditioning.

Official Title
-----------------
Brain Imaging and Pain: Analysis of Placebo Analgesia

Conditions
-----------------
Brain Imaging of Placebo Analgesia

Intervention / Treatment
-----------------
* Other: Placebo Instructions
* Other: Control condition


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: at least 18 years of age english speaking Exclusion Criteria: pain condition pregnant

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Placebo<br>Asymptomatic control participants receive Natural History and Placebo instructions in a within-subject design. There are no patients, or active agents in this study. It is not a Clinical Trial. | Other: Placebo Instructions<br>* There is no intervention in this study. It is not a Clinical Trial. The study is an investigation of the neural basis of placebo analgesia.<br>|
| Active Comparator: Control condition<br>The control condition represents a no-intervention, repeated baseline control, since the active intervention in this study is placebo. | Other: Control condition<br>* This protocol represents an investigation of the neural mechanisms of placebo analgesia. As such, it does not represent the traditional clinical trial design. Instead the active intervention is a placebo, and the comparison condition is a no-intervention control.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Brain Imaging Results | This outcomes represents the neural network underpinnings of the placebo analgesic response. It is the result of a network analysis using structural equation modeling of fMRI determined brain activations. | 2 weeks from baseline |