Effects of Non Invasive Brain Stimulation During Prolonged Experimental Pain

Effects of Non Invasive Brain Stimulation on Experimental Pain

Non invasive brain stimulation (NIBS) of the primary motor cortex (M1) through transcranial direct current stimulation (tDCS) has been widely investigated in research and clinical settings in order to modulate brain plasticity and improve clinical pain. Interestingly, newly developed paradigms i.e. tDCS of the resting state motor network have proved higher modulatory effects in terms of corticospinal excitability when compared to traditional M1 tDCS.

However, little is known about the effects of tDCS on the frequency changes of alpha oscillations (alpha peaks).

Interestingly, previous studies show a correlation between reduced frequencies of alpha peaks during 1-hour experimental pain in comparison to baseline.

The present study aims to investigate the effects of tDCS of the resting state motor network on the frequency and power of alpha peaks during prolonged experimental pain during 24 hours.

Study Overview

• Status: Completed
• Conditions: Pain; Prolonged Experimental Pain
• Intervention / Treatment: Device: Transcranial direct current stimulation (tDCS) of the resting state motor network

Detailed Description

There is evidence that chronic pain alters the frequency of alpha peaks. Specifically, recent studies showed a correlation between decreased frequency of alpha peaks and perceived pain. Furthermore, a correlation was found between high pain sensitivity and slower alpha oscillations during prolonged pain during 1 hour.

To date, the effects of prolonged experimental pain during 24 hours on brain oscillations has not been explored. Moreover, it is unknown whether non invasive brain stimulation (NIBS) through transcranial direct current stimulation (tDCS) can revert these pain-related feature.

It is hypothesized that prolonged pain during 24 hours will reduce the frequency of alpha peaks and tDCS of the resting state motor network will revert it to baseline values.

Furthermore, it is thought that decreased frequency of alpha peaks will be correlated with perceived pain intensity on Day 1 (before receiving the first tDCS session).

• Study Type: Interventional
• Enrollment (Actual): 44
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Denmark
  • Nordylland
    • Aalborg, Nordylland, Denmark, 9000
      • Aalborg University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 21 years to 50 years (ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Right-handed healthy men and women in the age 21-50 years who speak and understand English

Exclusion Criteria:

• Lack of ability to cooperate
• History of chronic pain or current acute pain
• Pregnancy
• Drug addiction defined as the use of cannabis, opioids or other drugs
• Present and previous neurologic, musculoskeletal or mental illnesses
• Chili allergies
• Current use of medications that may affect the trial
• Contraindications to rTMS application (history of epilepsy, metal implants in head or jaw, etc.)
• Failure to pass the questionnaire for tDCS

Study Plan

How is the study designed?

Design Details

• Primary Purpose: BASIC_SCIENCE
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: TRIPLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
ACTIVE_COMPARATOR: Active tDCS of the resting state motor network; The active comparator is the Active tDCS group. The active tDCS will target the resting-state motor network and will apply a distributed direct current during the whole session. (The TIME during the direct current is applied is the only difference with Sham tDCS) Each tDCS session lasts 20 minutes and applies a total current of 4mA.	Device: Transcranial direct current stimulation (tDCS) of the resting state motor network; Transcranial direct current stimulation (tDCS) delivers a low intensity current of up to 4 mA per session through small and circular shaped electrodes applied over the scalp. This induces a weak but focal electrical field that may modify the excitability of the underlying cortical target in a polarity and activity dependent fashion.
SHAM_COMPARATOR: Sham tDCS of the resting state motor network; This study has a parallel design and 2 groups: Active tDCS and Sham tDCS. Sham tDCS applies a standard sham protocol consisting of ramping up and down during 30 seconds at the beginning and at the end of each tDCS session. Each tDCS session lasts 20 minutes and applies a total current of 4mA.	Device: Transcranial direct current stimulation (tDCS) of the resting state motor network; Transcranial direct current stimulation (tDCS) delivers a low intensity current of up to 4 mA per session through small and circular shaped electrodes applied over the scalp. This induces a weak but focal electrical field that may modify the excitability of the underlying cortical target in a polarity and activity dependent fashion.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Frequency of alpha peaks	The frequency of alpha peaks will be extracted through electroencephalography (EEG) in the sensorimotor areas (Central-Parietal) of the brain. It is hypothesized that the frequency of alpha peaks will be reduced due to prolonged pain. It is expected that tDCS of the resting state motor network will revert the frequency to baseline values or even higher.	24 hours
Perceived pain intensity	Perceived pain intensity will be rated in a 0-10 Numerical rating scale (NRS): 0 no pain and 10 worst pain imaginable. Prolonged pain will increase perceived pain intensity. It is expected that active tDCS will not be able to reduce perceived pain intensity in comparison to sham tDCS.	24 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Amplitude of alpha peak	Similar to the primary outcome, the amplitude of the alpha peak will be extracted through EEG in the sensorimotor area. It is expected that prolonged pain will be able to reduce the amplitude of alpha peaks and tDCS will increase it back to baseline values or even higher.	24 hours
Power of alpha oscillations	Spectral analysis will be performed on alpha activity and it is expected that this outcome will be reduced by prolonged pain and tDCS of the resting state motor network will be able to normalize it.	24 hours

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Amplitude of Mu-oscillations during motor imagery	Amplitude of Mu-oscillations will be extracted from EEG during motor imagery tasks (abduction-adduction of index finger). It is expected that prolonged pain and motor imagery will produce a desynchronization of Mu-oscillations and on the contrary active tDCS will be able to synchronize it back similar to pain-free state.	24 hours

Collaborators and Investigators

• Sponsor: Aalborg University

Study record dates

Study Major Dates

• Study Start (ACTUAL): February 1, 2020
• Primary Completion (ACTUAL): July 30, 2020
• Study Completion (ACTUAL): July 30, 2020

Study Registration Dates

• First Submitted: January 27, 2020
• First Submitted That Met QC Criteria: January 27, 2020
• First Posted (ACTUAL): January 29, 2020

Study Record Updates

• Last Update Posted (ACTUAL): November 20, 2020
• Last Update Submitted That Met QC Criteria: November 19, 2020
• Last Verified: November 1, 2020

More Information

Terms related to this study

• Other Study ID Numbers: N-20180092

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No