Photo Credit: iStock.com/AlexanderFord

Research shows that a home-based, self-directed EEG neurofeedback intervention may improve corneal neuropathic pain severity and interference in adults.

A home-based, self-directed electroencephalogram (EEG) neurofeedback intervention may improve pain severity and pain interference in adults with corneal neuropathic pain (CNP), according to study results published online in The Journal of Pain.

“The findings support the potential effects of this intervention in reducing pain severity across four participants when comparing the baseline phase to the intervention phase, as well as to both the first follow-up and the 5-week follow-up phases,” wrote corresponding author Negin Hesam-Shariati, PhD, of the University of New South Wales, and study coauthors. “Improvements in pain interference were observed only when comparing the baseline phase to the 5-week post-intervention phase.”

Multiple‑Baseline Study Design

The researchers employed a rigorous multiple‑baseline, single‑case experimental design across four phases: baseline, intervention, immediate follow‑up, and five‑week follow‑up. Four adults with clinically confirmed CNP completed daily pain assessments. Baseline durations were staggered (7, 10, 14, and 17 days) to strengthen causal inference, after which participants underwent 20 neurofeedback sessions over a four-week period.

“The multiple‑baseline design estimates the effect of an intervention by demonstrating that any observed changes in the outcome measures are systematically aligned with the initiation of the intervention,” the authors explained.

Neurofeedback Protocol

The intervention consisted of five rounds of neurofeedback games, each lasting approximately 2 minutes, designed to suppress theta and high-beta activity while reinforcing the sensorimotor rhythm.

“Throughout the neurofeedback games, participants were instructed to minimize physical movement and employ the recommended mental strategies to regulate the targeted bands to receive positive visual feedback from the games,” the researchers wrote. “The recommended strategies included positive thinking, focusing on game features, and practicing breathing exercises. These techniques help participants to relax, modulate their brain activity, and make conscious or below-awareness links between their used mental strategies and the visual feedback from the games.”

Primary Outcomes

The researchers reported a medium effect on pain severity and pain interference across participants between their baseline and 5-week follow-up. On an individual level, three participants experienced significant improvement in pain severity and interference between baseline and 5-week follow-up. Visual inspection of graphed data also indicated reductions in pain severity and pain interference, although they were not considered clinically meaningful.

Implications & Recommendations

“This single‑case experimental design study raises the possibility that the intervention may improve pain severity and interference for some individuals,” the team concluded, adding, “Variability in outcomes highlights the need for future research to better understand individual responses and optimize the intervention effect.”