Skip to main content
OpenTrials
Completed

NCT Number: NCT03102710

Neuromodulation of Lidocaine and Capsaicin Cream Effects on Pain Experience

The aim of this study is to use a brain stimulation tool called transcranial direct current stimulation (tDCS) to investigate the analgesic (reducing sensitivity to pain) effects of lidocaine cream and the hyperalgesic (increasing sensitivity to pain) effects of capsaicin cream using a neutral cream as a control. tDCS stimulation has been shown to temporarily influence the way the stimulated part of the brain functions. With this method, the involvement of specific parts of the brain can be investigated in the working of the brain as a whole.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

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

Age range

21 year–50 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Massachusetts General Hospital

Charlestown, Massachusetts, 02129, United States

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Right handed healthy male and female adults aged 21-50
  • No contraindications to fMRI scanning
  • At least a 10th grade English-reading level; English can be a second language provided that the patients feel they understand all the questions used in the assessment measures.

Exclusion criteria

  • Current or past history of major medical, neurological, or psychiatric illness
  • Claustrophobia
  • History of head trauma
  • Instability of responses to experimental pain
  • Non-fluent speaker of English
  • Presence of any contraindications to fMRI scanning. For example: cardiac pacemaker, metal implants, fear of closed spaces, pregnancy
  • History of alcohol/substance abuse

Treatment and study plan

Transcranial direct current stimulation (tDCS)

Device

tCDS safely applies a weak electrical current to your scalp using two sponge electrodes that look like flat circular pads. The pads will be held in place on your head with a neoprene cap. The pads will be attached to a generator that will send a weak stimulus to your scalp. This current influences the way that your brain cells work. When the stimulus starts, you might feel a tingling sensation underneath the electrode pads. That sensation is not painful and goes away in seconds.

Lidocaine cream

Other

Lidocaine cream will be applied on the arm to reduce pain sensitivity (analgesia).

Capsaicin cream

Other

Capsaicin cream will be applied on the arm to increase pain sensitivity (hyperalgesia).

control cream

Other

A neutral cream will be applied on the arm as a control.

Primary outcomes

  1. Comparison of Functional Connectivity Changes of the DLPFC Before and After tDCS Stimulation

    Time frame: up to 2 weeks

    We investigated the effects of cathodal (inhibition) and anodal (enhancement) tDCS on rDLPFC functional connectivity (FC) with the supplementary motor area (SMA) and anterior insula. Higher Fisher Z-scores represent greater resting-state functional connectivity.

  2. fMRI Resting States Functional Connectivity Changes During Pain Stimulation

    Time frame: up to 2 weeks

    We measured changes in blood oxygen level-dependent (BOLD) activity in the brain during pain stimulation. In the outcome measure data table, "placebo contrast" indicates lidocaine - neutral and "nocebo contrast" indicates capsaicin - neutral.

Secondary outcomes

  1. Gracely Sensory Scale Pain Rating Changes in Response to Lidocaine and Capsaicin Creams and tDCS

    Time frame: up to 2 weeks

    The Gracely Sensory Scale allows participants to rate the intensity of heat pain stimuli on a scale from 0 to 20, with 0 indicating no pain sensation and 20 indicating extremely intense pain. The outcome measure data table shows mean pain ratings for the lidocaine, capsaicin, and neutral creams after enhancement, inhibition, or sham tDCS stimulation.

Sponsors and collaborators

Lead sponsor

Massachusetts General Hospital

Other

Registry information

Official study title

Neuromodulation of Placebo and Nocebo Effects

Important dates

Study start
2016
Primary completion
2019
Study completion
2019
First posted
Apr 6, 2017
Registry last updated
Jul 7, 2020

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.