Table 1.
Neurofeedback training protocol details.
| Study | Data for section 1.2 and Figure 3B | Data for section 1.3 | Data for section 1.4 | |||
|---|---|---|---|---|---|---|
| Target | Training | Neurofeedback run periods and timing | Feedback | Instructed strategies | Regulation (total time) | |
| Aranyi et al. (2016) | Bilateral dlPFC asymmetry | 1 session/1 practice run, 8 real runs/1 trial, 1 day of training | 15 s rest/3 s instruction/40 s mental counting baseline/10 s rest/3 s instruction/40 s regulation/7 s rest | Immediate visual feedback, engagement (e.g., gaze, smile) of virtual agent | Express positive feelings toward the agent in order to capture its interest | 6 min |
| Barth et al. (2016) | PFC | 8 sessions/1 run/12 trials/ 30 s/8 days over 2 weeks | 30 s relaxation (deactivation)/30 s regulation (activation) | Immediate visual feedback of all channels (color-coded) | Not reported | 48 min |
| Fujimoto et al. (2017) | SMA | 1 session real and 1 session sham NF/16 trials/5 s/2 days | 8–15 s rest/5 s regulation | Immediate visual feedback, height and color of vertical bar | No strategies instructed | 80 s |
| Hosseini et al. (2016) | dlPFC | 4 sessions NF during verbal working memory task/1 run/80 trials/4 days over 2 weeks | 8–10 s working memory trial (encoding and retention)/2 s test/6–8 s rest and feedback presentation | Delayed feedback, line plot displaying changes during previous ten trials | Meta-cognitive strategies | 48 min |
| Hudak et al. (2017) | Bilateral dlPFC/IFG | 8 sessions/2 runs NF/12 trials/1 run transfer/8 trials/session 1–4: 50/50%, session 5–8: 80/20% activation/deactivation trials/8 days over 2 weeks | 20 s rest (5 s baseline)/30 s regulation/2 s reward | Immediate visual feedback, virtual classroom scenario: brightness of the lighting in the classroom, reinforcement after each trial | No strategies instructed | 96 + 32 min transfer |
| Hudak et al. (2018) | Bilateral dlPFC/IFG | 30 sessions/2 runs NF/12 trials/1 run transfer/8 trials/50/50% activation/deactivation trials/30 days over 12–49 weeks, 3 weeks intermission after session 15 | 30 rest (5 s baseline)/30 s regulation/2 s reward | Immediate visual feedback was presented via commercial EEG-NF system (moving objects and 2 s reinforcement) | Not reported | 360 + 120 min transfer |
| Kanoh et al. (2011) | Left sensorimotor cortex | 5 sessions/6 runs/5 trials/ 20 s/5 days of training | 40–43 s rest/20 s up-regulation | Immediate visual feedback (length of white bar) | Motor imagery of right hand | 50 min |
| Kimmig et al. (2018) | Bilateral dlPFC/IFG | 15 sessions/2 runs NF/12 trials/1 run transfer/8 trials/75/25% up-/downregulation/15 days over 5–9 weeks, from 7th session: distractor background pictures with fear-related contents | 30 s rest (5 s baseline)/30 s regulation/2 s reward | Immediate visual feedback, moving dot, and reinforcement “Well done!,” anxiety-related or neutral background pictures from 7th session onwards | Not reported | 180 + 60 min transfer |
| Kinoshita et al. (2016) | Bilateral frontal pole cortex | 1 session/6 runs (2 runs real/2 runs sham NF/2 runs transfer) 18 trials/1 day of training | 16 s rest/10 s up-regulation | Immediate visual feedback (blue bar) | Memory, executive functions, and verbal fluency strategies suggested | 6 min real + 6 min transfer |
| Kober et al. (2014) | Motor cortex asymmetry | 8 sessions/2 runs/40 trials/8 different days | 7–11 s rest/6–8 s regulation | Immediate visual feedback, moving dot + numerical score continuously updated | Kinesthetic motor imagery | ~75 min |
| Kober et al. (2015) | Bilateral IFG | 7 sessions/1 run/25 trials/7 different days | 27–33 s rest/17–23 s up-regulation | Immediate visual feedback, moving dot + numerical score continuously updated | Motor imagery | ~58 min |
| Kober et al. (2018) | Bilateral IFG | 1 session/1 run/20 trials/1 day (also NF during rest, but instructed to relax and bring signal back to baseline) | 30 s rest/17–23 s regulation | Immediate visual feedback (color-coded on a schematic head model) | Kinesthetic motor imagery | ~7 min |
| Lapborisuth et al. (2017) | Left motor cortex | 1 session/8 runs (motor imagery and execution)/4 runs with NF/4 runs without/6 trials | 15 s rest/15 s up-regulation | Immediate visual feedback of all channels on a color-coded topographic image | Motor imagery/motor execution | 6 min |
| Lee et al. (2015) | Sensory motor cortex | 1 session, 2 runs, 1 run treadmill walking without NF, 1 run with NF | 15 s rest/10 s up-regulation | Immediate visual feedback (red bar) | Not reported | 100 s |
| Li et al. (2019) | Right lateral OFC | 1 session, 1 run 6–10 trials to learn strategy, 4 real training runs/4 trials/one day/10–30 min break in between | 25 s rest/25 s up-regulation | Immediate visual feedback, animation: “Lift a stone in front of a beach landscape” | No specific strategies instructed | ~9–11 min |
| Liu et al. (2016) | Frontal and temporal face processing regions | 5 sessions/2 runs/1 run: functional localizer/4 trials morphing faces/1 run training/10 trials, 5 days over 5 weeks | 30 s rest/house-matching 20 s/face-matching (up-regulation) 28 s/2s feedback/reward display | Delayed feedback, points displayed after each trial, points were later converted to cash | No specific strategies instructed | ~23 min |
| Marx et al. (2015) | Bilateral dlPFC/IFG | 12 sessions/2 runs NF/12 trials/1 run transfer/8 trials, 50/50% activation/deactivation trials, 12 days within 4–6 weeks | 25 s rest (5 s baseline)/30 s regulation/2 s reward | Immediate visual feedback was presented via commercial EEG-NF system (moving objects and 2 s reinforcement) | Not reported | 144 + 48 min transfer |
| Mihara et al. (2012) | Left premotor cortex | 1 session real/1 session sham NF/15 trials/1 day | 8–15 s rest/5 s regulation | Immediate visual feedback, height and color of vertical bar | Kinesthetic motor imagery | 75 s |
| Mihara et al. (2013) | Ipsilesional premotor cortex | 6 sessions/32 trials/6 days over 2 weeks/10 min motor imagery training without NF before each session | 8–15 s rest/5 s regulation | Immediate visual feedback, height and color of vertical bar | Kinesthetic motor imagery | 16 min |
| Narita (2015) | Left PFC | 2 sessions/7 runs/6 trials/2 days over 1 week? (but not clearly reported) | 15 s rest/30 s regulation | Immediate visual feedback, color of monitor | Not reported | ~42 min |
| Trambaiolli et al. (2018) | Frontal and occipital networks | 1 session/2 runs classifier training/2 runs NF/11 trials (5) trials real, 3 trials fixed, 3 trials random feedback (neutral and positive affect conditions) | 5 s fixation cross/2 s instruction/30 s positive or neutral affect condition/self-paced self-evaluation | Immediate visual feedback, amorphous figure | Imagine positive personal experiences | 5 min |
| Weyand et al. (2015) | Bilateral PFC | 16 sessions/3 runs/20–22 trials (up- and down-regulation)/15 sessions within 3 weeks, last session 10 days later/session 1–5: select strategy/session 6–10: practice strategies/session 11–15: stop strategies, use desire to regulate/session 16: follow-up | 20 s rest/17 s regulation | Immediate visual feedback, color-coded topographic image, ball that rises and falls, and game feedback | Yes, specific strategies instructed | 277 min |
dlPFC, dorsolateral prefrontal cortex; EEG, electroencephalography; IFG, inferior frontal gyrus; NF, neurofeedback; OFC, orbitofrontal cortex; PFC, prefrontal cortex; SMA, supplementary motor area.