Predicting Pain Response to Transcranial Direct Current Stimulation for Phantom Limb Pain in Limb Amputees

Inclusion criteria

• Able to provide informed consent to participate in the study.
• Subject is older than 18 years.
• 3 months of phantom limb pain (experienced regularly for at least once a week) after the amputated limb has completely healed.
• Average pain of at least 4 on a numeric rating scale in the previous week (NRS; ranging from 0 to 10).
• If the subject is taking any medications, dosages must be stable for at least 2 weeks prior to the enrollment of the study.

Exclusion criteria

• Pregnancy or trying to become pregnant in the next 2 months.
• History of alcohol or drug abuse within the past 6 months as self-reported.
• Presence of the following contraindication to transcranial direct current stimulation Ferromagnetic metal in the head (e.g., plates or pins, bullets, shrapnel) Implanted head electronic medical devices (e.g., cochlear implants)
• Head injury resulting in loss of consciousness for at least 30 min or pos-traumatic amnesia for greater than 24 hours, as self-reported
• Unstable medical conditions (e.g. uncontrolled diabetes, uncompensated cardiac issues, heart failure or chronic obstructive pulmonary disease).
• Uncontrolled Epilepsy
• Suffering from severe depression (as defined by a score of >30 in the Beck Depression Inventory).*
• History of unexplained fainting spells or loss of consciousness as self-reported during the last 2 years.
• History of neurosurgery, as self-reported.