Transcranial Direct Current Stimulation and Modulation of Affect and Pain

NCT06989749 | Recruiting

• 1 other identifier: STUDY00032315
• Study Type: interventional
• Target: 50
• Locations: 1 country
• Sites: 1

Brief Summary

This double-blind randomized crossover study aims to examine the effects of left primary motor cortex (M1) tDCS on evoked thermal pain perception, pain-related decision making, and placebo effects by manipulated pain and monetary offers accepted by others. The investigators plan to collect data for up to 50 participants who undergo four separate sessions: an initial pain calibration session and three experimental sessions with either anodal, cathodal, or sham tDCS. Each session includes pain testing before and after a single tDCS protocol (either anodal, cathodal, or sham), a pain-monetary decision-making task, and social placebo pain tests. All tasks following tDCS will take place inside the MR scanner. The investigators hypothesize that anodal M1 tDCS will decrease pain ratings, and that cathodal tDCS will increase them, both relative to the sham condition. The investigators will also examine the effects of M1 tDCS on social decision-making to examine whether it affects participants' valuation of pain and their altruistic behavior, as well as how these same factors impact pain sensation in the placebo task. The investigators hypothesize that participants will behave hyperaltruistically during the decision-making task, and that the same factors that influence choice will also impact pain perception in the same context.

Conditions

We Are Not Studying a Disease or Condition

Keywords

transcranial direct current stimulation; experimental pain; pain-related decision-making; social placebo effects

Outcome Measures

Primary Outcomes (1)

• Pain Visual Analogue Scale

  Self-reported pain level following each thermal stimulus, measured on a visual analog scale. 0-100 scale with 0 indicating no pain and higher values indicating more pain.

  3-10 sec post-stimulus throughout testing sessions, on average complete within 1 month

Study Arms (1)

Within-person Crossover

OTHER

This within-person crossover study involves a single arm, where each participant experiences an initial pain calibration session, followed by three full study sessions involving anodal, cathodal, or sham tDCS interventions. Only one intervention type (anodal, cathodal, or sham) is applied per session, in a randomized and double-blind fashion.

Other: Anodal tDCS; Other: Cathodal tDCS; Other: Sham tDCS

Interventions

Anodal tDCS OTHER

Transcranial direct current stimulation (tDCS) is an experimental manipulation of brain circuitry using electrical current applied to the scalp. The equipment is commercially available (StarStim8, Neuroelectrics, Spain) and marketed for experimental research on brain function. Current is applied at 2 mA for 20 minutes. Electrodes are placed on the C3 and FP2 regions. There is a 30-second ramp-up and 30-second ramp-down of stimulation for each tDCS condition to minimize any discomfort during stimulation. In the anodal condition, real tDCS stimulation enters from the C3 electrode, and exits at the FP2 electrode.

Also known as: Anodal Transcranial Direct Current Stimulation

Within-person Crossover

Cathodal tDCS OTHER

Transcranial direct current stimulation (tDCS) is an experimental manipulation of brain circuitry using electrical current applied to the scalp. The equipment is commercially available (StarStim8, Neuroelectrics, Spain) and marketed for experimental research on brain function. Current is applied at 2 mA for 20 minutes. Electrodes are placed on the C3 and FP2 regions. There is a 30-second ramp-up and 30-second ramp-down of stimulation for each tDCS condition to minimize any discomfort during stimulation. In the cathodal condition, real tDCS stimulation enters from the FP2 electrode, and exits at the C3 electrode.

Also known as: Cathodal Transcranial Direct Current Stimulation

Within-person Crossover

Sham tDCS OTHER

This is the sham (or placebo) tDCS intervention. The tDCS device is applied for one minute, for a 30-second ramp-up and 30-second ramp-down of stimulation.

Also known as: Sham Transcranial Direct Current Stimulation

Within-person Crossover

Eligibility Criteria

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

You may qualify if:

• ages 18-55
• Participants must be capable of performing experimental tasks (e.g., are able to read)
• Fluent or native speakers of English

You may not qualify if:

• 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)
• No history of stroke or other major neurological diagnosis.
• 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).

Sponsors & Collaborators

• Trustees of Dartmouth College: lead

Study Sites (1)

Dartmouth College

Hanover, New Hampshire, 03755, United States

RECRUITING

MeSH Terms

Interventions

Transcranial Direct Current Stimulation

Intervention Hierarchy (Ancestors)

Electric Stimulation Therapy; Therapeutics; Convulsive Therapy; Psychiatric Somatic Therapies; Behavioral Disciplines and Activities; Electroshock; Psychological Techniques

Central Study Contacts

Tor Wager D Principal Investigator, PhD

CONTACT

603-646-2196; Tor.D.Wager@Dartmouth.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Masking Details: Participants were blind to the tDCS type applied in each session. Personnel interacting directly with the study subjects are blind to the tDCS type in each session (Commonly known as "double blind"). Personnel analyzing data collected from the study are blind to the tDCS type applied in each session. Participants are blind to the exact temperatures (in Celsius) used in the study. Participants are blind to the temperatures received at the end of the decision making task.
• 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 8, 2025
• First Posted: May 25, 2025
• Study Start: September 9, 2023
• Primary Completion (Estimated): September 1, 2026
• Study Completion (Estimated): September 1, 2026
• Last Updated: May 25, 2025

Record last verified: 2025-05

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)