Systematic Review and Meta-Analysis on the Effects of Neurofeedback Training of Theta Activity on Working Memory and Episodic Memory in Healthy Population

The main purpose of this study was to investigate the effects of neurofeedback training (NFT) of theta activity on working memory (WM) and episodic memory (EM) in healthy participants via a systematic review and meta-analysis. A total of 337 articles obtained from electronic databases were assessed; however, only 11 articles met the criteria for meta-analysis after manually screening and eliminating unnecessary studies. A meta-analysis calculating the Hedges’ g effect size metric with 95% confidence intervals using random effects models was employed. Heterogeneity was estimated using I(2) statistics. Theta NFT is effective in improving memory outcomes, including WM with a Hedges’ g of 0.56 [0.10; 1.02] (I(2) = 62.9% and p = 0.02), and EM with a Hedges’ g of 0.62 [0.13; 1.10] (I(2) = 42.04% and p = 0.01). Overall, the results suggest that theta NFT seems to be useful as nonpharmacological/adjunct training to improve WM and EM in healthy participants.