The analgesic effect of EEG neurofeedback for people with chronic pain: A systematic review and meta-analysis

Electroencephalographic (EEG) neurofeedback has been utilised to regulate abnormal brain activity associated with chronic pain. In this systematic review, we synthesised the evidence from randomised controlled trials (RCTs) to evaluate the effect of EEG neurofeedback on chronic pain using random effects meta-analyses. Additionally, we performed a narrative review to explore the results of non-randomised studies. The quality of included studies was assessed using Cochrane risk of bias tools, and the GRADE system was used to rate the certainty of evidence. Ten RCTs and 13 non-randomised studies were included. The primary meta-analysis on nine eligible RCTs indicated that although there is low confidence, EEG neurofeedback may have a clinically meaningful effect on pain intensity in short-term. Removing the studies with high risk of bias from the primary meta-analysis resulted in moderate confidence that there remained a clinically meaningful effect on pain intensity. We could not draw any conclusion from the findings of non-randomised studies, as they were mostly non-comparative trials or explorative case series. However, the extracted data indicated that the neurofeedback protocols in both RCTs and non-randomised studies mainly involved the conventional EEG neurofeedback approach, which targeted reinforcing either alpha or sensorimotor rhythms and suppressing theta and/or beta bands on one brain region at a time. A post-hoc analysis of RCTs utilising the conventional approach resulted in a clinically meaningful effect estimate for pain intensity. Although there is promising evidence on the analgesic effect of EEG neurofeedback, further studies with larger sample sizes and higher quality of evidence are required.