Neuromodulation of Lidocaine and Capsaicin Cream Effects on Pain Experience

Mass General Brigham

Status: Completed

Conditions: Pain

Treatments: Other: Control cream; Device: transcranial direct current stimulation (tDCS); Other: Capsaicin cream; Other: Lidocaine cream

Study type: Interventional

Funder types: Other

Identifiers

NCT03102710

2015P000685

Details and patient eligibility

About

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.

Enrollment: 103 patients

Sex: All

Ages: 21 to 50 years old

Volunteers: Accepts Healthy Volunteers

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

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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103 participants in 3 patient groups

tDCS Enhancement

Experimental group

Description:

In this group, the transcranial direct current stimulation (tDCS) stimulates the areas of the brain being examined in this study to increase their activity.

Treatment:

Device: transcranial direct current stimulation (tDCS)

Other: Control cream

Other: Lidocaine cream

Other: Capsaicin cream

tDCS Inhibition

Experimental group

Description:

In this group, the transcranial direct current stimulation (tDCS) inhibits the areas of the brain being examined in this study to decrease their activity.

Treatment:

Device: transcranial direct current stimulation (tDCS)

Other: Control cream

Other: Lidocaine cream

Other: Capsaicin cream

Sham tDCS

Sham Comparator group

Description:

Sham transcranial direct current stimulation (tDCS) does not provide real stimulation though you will not know this until your debriefing at the end of the study. Sham will be used to determine if the results of this study are due to the tDCS or other reasons.

Treatment:

Device: transcranial direct current stimulation (tDCS)

Other: Control cream

Other: Lidocaine cream

Other: Capsaicin cream