Interactions Between Placebo Effects and Mindful Awareness State

NCT07108101 | Not Yet Recruiting

• 1 other identifier: 467254
• Study Type: interventional
• Target: 120
• Locations: 1 country
• Sites: 1

Brief Summary

In this experiment,the investigators study the effects of interpersonally induced placebo effects and a mindful awareness induction on negative affect. Specifically, it will be examining the effects of interpersonally induced placebo effects (sham tDCS vs. control) and a mindful awareness induction (mindful state vs. control), as well as their interaction. Each group will undergo fMRI scanning and physiological recording will performing the Multimodal Negative Affect Task (MNAT).

Conditions

Placebo Effect; Mindfulness; Pain; Transcranial Direct Current Stimulation (tDCS)

Outcome Measures

Primary Outcomes (3)

• Pain Ratings

  Participants report subjective pain experience after each trial on a well-validated Generalized Linear Magnitude scale (GLMS) with anchors of "No pain" and "Most intense pain imaginable". Raw units are on a 0-180 scale.

  3-10 sec post-stimulus throughout testing sessions, with all sessions complete within 1 month

• Subjective fear ratings

  Participants report subjective fear experience after each trial on a well-validated Generalized Linear Magnitude scale (GLMS) with anchors of "No fear" and "Most intense fear imaginable"

  3-10 sec post-stimulus throughout testing sessions, with all sessions complete within 1 month

• Cognitive effort ratings

  Participants report cognitive effort experience after each trial on a well-validated Generalized Linear Magnitude scale (GLMS) with anchors of "No effort" and "Most effort imaginable"

  3-10 sec post-stimulus throughout testing sessions, with all sessions complete within 1 month

Secondary Outcomes (1)

• Electrodermal autonomic responses to painful heat, fear-related images and cognitive effort.

  Peri-stimulus throughout testing sessions, with all sessions complete within 1 month

Study Arms (4)

mindfulness (session 1)+ real tdcs, sham tdcs (session 2)

EXPERIMENTAL

Assigned to the mindfulness group in session 1. Will experience real tdcs, followed by sham tdcs for session 2.

Behavioral: tDCS stimulation (sham); Behavioral: tDCS stimulation (real); Behavioral: Mindful state induction

mindfulness (session 1) + sham tcds, real tdcs (session 2)

EXPERIMENTAL

Assigned to the mindfulness group in session 1. Will experience sham tdcs, followed by real tdcs for session 2.

Behavioral: tDCS stimulation (sham); Behavioral: tDCS stimulation (real); Behavioral: Mindful state induction

no mindfulness (session 1) + real tdcs, sham tcds (session 2)

EXPERIMENTAL

Assigned to the no-mindfulness control group in session 1. Will experience real tdcs, followed by sham tdcs for session 2.

Behavioral: tDCS stimulation (sham); Behavioral: tDCS stimulation (real); Behavioral: No minfulness induction

no mindfulness (session 1) + sham tdcs, real tdcs (session 2)

EXPERIMENTAL

Assigned to the no-mindfulness control group in session 1. Will experience sham tdcs, followed by real tdcs for session 2.

Behavioral: tDCS stimulation (sham); Behavioral: tDCS stimulation (real); Behavioral: No minfulness induction

Interventions

tDCS stimulation (sham) BEHAVIORAL

Participants will receive sham tDCS stimulation in a 20 minute long task. Targets will be fitted with the tDCS stimulation electrode cap and instructed that they will receive 20 minutes of tDCS stimulation for the task. Sham tDCS will target the motor cortex at 2mA for 15 sec at the beginning of the session, and then the stimulator will turn off. The participant will then sit for the remaining time of the session with the electrode cap on their heads but turned off and not delivering stimulation. All participants will receive sham tDCS stimulation (n=120).

mindfulness (session 1) + sham tcds, real tdcs (session 2); mindfulness (session 1)+ real tdcs, sham tdcs (session 2); no mindfulness (session 1) + real tdcs, sham tcds (session 2); no mindfulness (session 1) + sham tdcs, real tdcs (session 2)

tDCS stimulation (real) BEHAVIORAL

In their second session, participants will receive real tDCS stimulation in a 20 minute long task. Targets will be fitted with the tDCS stimulation electrode cap and instructed that they will receive 20 minutes of tDCS stimulation for the task. Real tDCS stimulation will target the motor cortex at 2mA for 20 minutes (full duration of task). All participants will receive real tDCS stimulation (n=120).

mindfulness (session 1) + sham tcds, real tdcs (session 2); mindfulness (session 1)+ real tdcs, sham tdcs (session 2); no mindfulness (session 1) + real tdcs, sham tcds (session 2); no mindfulness (session 1) + sham tdcs, real tdcs (session 2)

Mindful state induction BEHAVIORAL

Experimenters trained in high-competence and high-warmth will train Group 1 participants on mindful state induction (n=60). Participants will undergo two stages for this training: 1) pain education to increase beliefs in endogenous brain regulatory capacities; and 2) the Stanford Hypnotic Induction Profile (HIP) test of hypnotizability and hypnotic induction of a relaxed state receptive to suggestion. In Stage 1, participants will receive education that pain and affect are processes designed to protect the body from danger, which are transmitted rapidly and automatically to the brain. In Stage 2, participants are (a) seated in an upright, alert posture; and (b) receive suggestions that the ability to attend to and discriminate affective perceptions is achievable and that suppressing attention to the body and focusing on the task will allow them to perform optimally under pressure. Mindful state induction will only be explicitly instructed during session 1 for Group 1 participants.

mindfulness (session 1) + sham tcds, real tdcs (session 2); mindfulness (session 1)+ real tdcs, sham tdcs (session 2)

No minfulness induction BEHAVIORAL

Participants in the No-mindfulness group will go through comparable stages but with different instructions. In the first stage, they will receive education about pain and affect as protective processes of the body. In the second stage, they will be seated in an upright, alert posture and receive suggestions to focus on the task and suppress attention to the body.

no mindfulness (session 1) + real tdcs, sham tcds (session 2); no mindfulness (session 1) + sham tdcs, real tdcs (session 2)

Eligibility Criteria

• Age: 18 Years - 55 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

* No self-reported current or history of depression, bipolar disorder, or other psychiatric diagnosis * No self-reported current seizure disorder (i.e., seizure within past 10 years), or history of stroke or other major neurological diagnosis that can cause cognitive impairment * No self-reported current chronic pain, or acute pain within three months of the study period * No current migraine disorder (i.e., 15 headache days or more in 1 month) * No use of central nervous system-effective medication or other medication for neurological/psychiatric treatment * No self-reported substance abuse within the last six months * No contraindication to MRI or tDCS (e.g., pregnancy, claustrophobia, pacemakers, ear/cochlear implants, shrapnel injuries, clips, or other ferromagnetic/electrical objects/devices, diagnosed brain abnormality such as tumor, or skin lesions on the scalp.) * No contraindications for induced pain (e.g., no heart disease, high blood pressure, heart surgery, heart problems of any kind, severe asthma, respiratory problems of any kind, fibromyalgia, Raynaud's Syndrome or Disease, chronic pain, diabetes) * Participants must be capable of performing experimental tasks (e.g., are able to read), are fluent or native speakers of English * Participants must be able to tolerate the maximum level of thermal pain stimuli (for thermal stimuli)

Contact the study team to discuss eligibility requirements. They can help determine if this study is right for you.

Sponsors & Collaborators

• Trustees of Dartmouth College: lead

Study Sites (1)

Dartmouth College

Hanover, New Hampshire, 03755, United States

Location

MeSH Terms

Conditions

Pain

Interventions

salicylhydroxamic acid

Condition Hierarchy (Ancestors)

Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Tor Wager, Ph.D.

  Dartmouth College

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Tor Wager, Ph.D.

CONTACT

6036462196; tor.d.wager@dartmouth.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Diana L. Taylor Distinguished Professor

Study Record Dates

• First Submitted: May 25, 2025
• First Posted: August 6, 2025
• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): June 1, 2028
• Study Completion (Estimated): November 30, 2028
• Last Updated: August 6, 2025

Record last verified: 2025-07

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)