The left dorsolateral prefrontal cortex (DLPFC) is involved in the experience and modulation of pain, and may be an important node linking pain and cognition. Repetitive transcranial magnetic stimulation (rTMS) to the left DLPFC can reduce chronic and experimental pain. However, whether left DLPFC rTMS can influence the development of chronic pain is unknown. Using repeated intramuscular injection of nerve growth factor to induce the development of sustained muscle pain (lasting weeks), 30 healthy individuals were randomized to receive 5 consecutive daily treatments of active or sham left DLPFC rTMS, starting before the first nerve growth factor injection on day 0. Muscle soreness and pain severity were collected daily for 14 days and disability on every alternate day. Before the first and 1 day after the last rTMS session, anxiety, depression, affect, pain catastrophizing, and cognitive performance on the attention network test were assessed. Left DLPFC rTMS treatment compared with sham was associated with reduced muscle soreness, pain intensity, and painful area (P < 0.05), and a similar trend was observed for disability. These effects were most evident during the days rTMS was applied lasting up to 3 days after intervention. Depression, anxiety, pain catastrophizing, and affect were unchanged. There was a trend toward improved cognitive function with rTMS compared with sham (P = 0.057). These data indicate that repeated left DLPFC rTMS reduces the pain severity in a model of prolonged muscle pain. The findings may have implications for the development of sustained pain in clinical populations.
Repetitive transcranial magnetic stimulation of left dorsolateral prefrontal cortex, compared with sham stimulation, reduces pain development in a long-lasting model of muscle pain.
aDepartment of Neural and Pain Sciences, University of Maryland School of Dentistry, Baltimore, MD, United States
bCenter to Advance Chronic Pain Research, University of Maryland, Baltimore, Baltimore, MD, United States
cDepartment of Health Science and Technology, Center for Neuroplasticity and Pain (CNAP), SMI, The Faculty of Medicine, Aalborg University, Aalborg, Denmark
dBrain Rehabilitation and Neuroplasticity Unit (BRAiN-u), Western Sydney University, School of Science and Heath, Sydney, Australia
Corresponding author. Address: Department of Neural and Pain Sciences, University of Maryland School of Dentistry, 650 W. Baltimore St, 8 South, Baltimore, MD 21201, United States. Tel.: 410 706 3476. E-mail address: email@example.com (D.A. Seminowicz).
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Received May 09, 2018
Received in revised form July 01, 2018
Accepted July 17, 2018