Transcranial Direct Current Stimulation of the Dorsolateral Prefrontal Cortex Alters Emotional Modulation of Spinal Nociception

Peter Maxwell Slepian; Christopher R France; Jamie L Rhudy; Brian C Clark

doi:10.1016/j.jpain.2020.10.007

Transcranial Direct Current Stimulation of the Dorsolateral Prefrontal Cortex Alters Emotional Modulation of Spinal Nociception

J Pain. 2021 May;22(5):509-519. doi: 10.1016/j.jpain.2020.10.007. Epub 2020 Nov 27.

Authors

Peter Maxwell Slepian¹, Christopher R France², Jamie L Rhudy³, Brian C Clark⁴

Affiliations

¹ Department of Anesthesia and Pain Management, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada; Department of Psychology, York University, Toronto, Ontario, Canada; Department of Psychology, Ohio University, Porter Hall, Athens, Ohio. Electronic address: maxwell.slepian@uhn.ca.
² Department of Psychology, Ohio University, Porter Hall, Athens, Ohio.
³ Department of Psychology, University of Tulsa, Lorton Hall, Tulsa, Oklahoma.
⁴ Department of Biomedical Sciences, Ohio University, Grosvenor Hall, Athens, Ohio.

PMID: 33253818
DOI: 10.1016/j.jpain.2020.10.007

Abstract

Emotion has a strong modulatory effect on pain perception and spinal nociception. Pleasure inhibits pain and nociception, whereas displeasure facilitates pain and nociception. Dysregulation of this system has been implicated in development and maintenance of chronic pain. The current study sought to examine whether emotional modulation of pain could be altered through the use of transcranial direct current stimulation (tDCS) to enhance (via anodal stimulation) or depress (via cathodal stimulation) cortical excitability in the dorsolateral prefrontal cortex. Thirty-two participants (15 female, 17 male) received anodal, cathodal, and sham tDCS on three separate occasions, followed immediately by testing to examine the impact of pleasant and unpleasant images on pain and nociceptive flexion reflex (NFR) responses to electrocutaneous stimulation. Results indicated that tDCS modulated the effect of image content on NFR, F(2, 2175.06) = 3.20, P= .04, with the expected linear slope following anodal stimulation (ie, pleasant < neutral < unpleasant) but not cathodal stimulation. These findings provide novel evidence that the dorsolateral prefrontal cortex is critical to emotional modulation of spinal nociception. Moreover, the results suggest a physiological basis for a previously identified phenotype associated with risk for chronic pain and thus a potentially new target for chronic pain prevention efforts. PERSPECTIVE: This study demonstrated that reduction of dorsolateral prefrontal cortical excitability by transcranial direct current stimulation attenuates the impact of emotional image viewing on nociceptive reflex activity during painful electrocutaneous stimulation. This result confirms there is cortical involvement in emotional modulation of spinal nociception and opens avenues for future clinical research.

Keywords: Emotion; Pain; Pain modulation, Transcranial direct current stimulation, Nociceptive flexion reflex.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Cortical Excitability / physiology*
Emotional Regulation / physiology*
Female
Humans
Male
Nociception / physiology*
Pain Measurement
Pattern Recognition, Visual / physiology
Prefrontal Cortex / physiology*
Reflex / physiology*
Spinal Cord / physiology*
Transcranial Direct Current Stimulation
Young Adult