Efficacy of neurofeedback training for improving attentional performance in healthy adults: A systematic review and meta-analysis

Figures

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  Fig. 1.. PRISMA flowchart of article search and inclusion.

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  Fig. 2.. Qualitative assessment of NFT studies included in the qualitative synthesis. (A) Histogram of publication year. (B) Subset(s) of attentional performance assessed in NFT studies. (C) Channels recorded for EEG-based NFT. (D) Frequency band(s) targeted to modulate in EEG-based NFT studies. Single and multiple indicate that a band was modulated by intervening single and multiple band(s), respectively. Abbreviations: E, Executive function; S, Spatial orientation; A, Arousal; SMR, sensorimotor rhythm.

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  Fig. 3.. Risk-of-bias assessment for each study considered for the meta-analysis. The red, yellow, and green symbols in each domain column indicate high, unclear, and low risk of bias, respectively. In the overall column, red, yellow, and green indicate high, moderate, and low risk of bias, respectively. Based on this analysis, two studies (red in the overall column) were eliminated from the meta-analysis.

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  Fig. 4.. Funnel plot showing the standardized mean differences from all experimental results included in the meta-analysis. The relative symmetry suggests low risk of publication bias.

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  Fig. 5.. Forest plot of NFT efficacy for improving attentional performance. (A) Overall effect size estimate. (B–E) Estimated effect sizes for each subtype of attentional performance (B), type of outcome measures (C), type of brain activity targeted for NFT (D), and type of control (E). The squares are the means and error bars are the 95% confidence intervals of estimated effect sizes comparing NFT to control conditions.