Effects of Transcranial Magnetic Stimulation (TMS) and Stimulus Controllability on Pain Perception

Medical University of South Carolina (MUSC)

Status: Completed

Conditions: Chronic Pain

Treatments: Device: Receiver Role Real TMS; Device: Receiver Role Sham TMS; Device: Operator Role Sham TMS; Device: Operator Role Real TMS; Device: All Participants Operator Role

Study type: Interventional

Funder types: Other

Identifiers

NCT01030133

Borckardt_19079

Details and patient eligibility

About

Although transcranial magnetic stimulation (TMS) is now considered a minimal risk intervention, is approved for the treatment of depression, and is widely used around the world, little is known about mechanisms of action of prefrontal rTMS for depression or pain. There is some evidence that the prefrontal cortex is involved in perception of control and may moderate the effects of perceived controllability on emotional reactivity to painful stimuli. The present study aims to investigate the effects of prefrontal rTMS and perceived controllability on pain perception in healthy adults.

Full description

Transcranial magnetic stimulation (TMS) is a minimally invasive brain stimulation technology that can focally stimulate the brain of an awake individual.1,2 A localized pulsed magnetic field transmitted through a figure-8 coil (lasting only microseconds) is able to focally stimulate the cortex by depolarizing superficial neurons3,4 which induces electrical currents in the brain.5 If TMS pulses are delivered repetitively and rhythmically, the process is called repetitive TMS (rTMS).

rTMS over the prefrontal cortex has been shown to produce temporary analgesic effects in healthy adults using laboratory pain methods and in patients with chronic pain of various etiologies. However, little is known about mechanisms of action.

Evidence from functional MRI studies suggests that participants' perceived controllability over pain stimuli is associated with decreased pain experience and decreased activation of cortical and subcortical areas involved with pain perception.6 Perceived controllability may involved prefrontal cortical circuits and may be involved in inhibition of limbic system responses to painful stimuli.

To date, no studies have investigated the interaction between prefrontal TMS and perceived controllability on pain perception in healthy adults. Building on extensive pilot work and experience in the area of laboratory pain assessment and TMS in the Brain Stimulation Laboratory at MUSC, the investigators propose to investigate the effects of perceived controllability and prefrontal TMS on pain perception in healthy adults. This study may help determine whether TMS can be used to stimulate a cortical area thought to be involved in perceived controllability, thus enhancing one's sense of controllability and thereby substantially reduce pain intensity and unpleasantness.

Although transcranial magnetic stimulation (TMS) is now considered a minimal risk intervention, is approved for the treatment of depression, and is widely used around the world, little is known about mechanisms of action of prefrontal rTMS for depression or pain. There is some evidence that the prefrontal cortex is involved in perception of control and may moderate the effects of perceived controllability on emotional reactivity to painful stimuli. The present study aims to investigate the effects of prefrontal rTMS and perceived controllability on pain perception in healthy adults.

Enrollment: 28 patients

Sex: All

Ages: 18 to 75 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• 18-75 years of age

Exclusion criteria

• history of seizures or epilepsy
• family history of seizures
• history of chronic pain conditions
• current depression
• anxiety disorders
• taking any medications shown to lower seizure threshold
• metal implants above the waist
• pregnant
• brain tumors or lesions
• pacemaker

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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28 participants in 3 patient groups

Real TMS

Active Comparator group

Description:

Participants in the real Transcranial Magnetic Stimulation (TMS) group will receive real stimulation across all interventions; the operator role Real TMS and receiver role Real TMS. rTMS will be used to stimulate the left prefrontal cortex using two Neuronetics TMS machines with figure-8, iron core coils at 10Hz and at 110% of resting motor threshold \[5 second trains following each trial (25 trials per visit)\].

Treatment:

Device: Receiver Role Real TMS

Device: Operator Role Real TMS

Sham TMS

Sham Comparator group

Description:

Participants in the sham Transcranial Magnetic Stimulation (TMS) group will receive sham stimulation across all interventions; the operator role Sham TMS and receiver role Sham TMS. Sham Stimulation involves 5 second trains of 10Hz rTMS in pairs alternating between real TMS and eSham TMS (randomly ordered). All sham treatment will be delivered with a specially designed, manufacture-provided sham TMS coil that looks and sounds identical to a real TMS coil but no magnetic current is transferred to the participant.

Treatment:

Device: Operator Role Sham TMS

Device: Receiver Role Sham TMS

All Participants Operator Role

Other group

Description:

All participants in Operator Role (Receiving real or sham TMS)

Treatment:

Device: Operator Role Sham TMS

Device: All Participants Operator Role

Device: Operator Role Real TMS