RESUMO
EEG neurofeedback (EEG-NFB) is a promising tool for the treatment of depressive disorders. However, many methods for the presentation of neurobiological reactions are available and it is widely unknown which of these feedback options are preferrable. Moreover, the influence of motivation on NFB training success is insufficiently studied. This study analyzed the efficacy of a novel EEG protocol (FC3/Pz) based on findings for NFB in depression. The role of four feedback options (Rumination, Anxiety, Meditation Master, Moving Art) from the NFB software "Brain Assistant" and motivation in EEG-based NFB performance was studied. Regarding "Anxiety" and "Rumination" visual feedback was used to evoke emotions; reinforcement (both negative and positive operant conditioning) was continuous. Regarding "Meditation Master" visual feedback was combined with continuous positive reinforcement. Regarding "Moving Art" 20-min calm nature films with neutral character were used; both visual and auditive feedback were applied. The reinforcement was positive and continuous. 13 healthy participants completed 15 EEG sessions over four months combining simultaneous frontal (aims: reduction of theta-, alpha- and high beta-activity, increase of low and mid beta-activity) and parietal training (aims: reduction of theta-, alpha 1-, mid and high beta-activity, increase of alpha 2- and low beta-activity). We observed significantly more pronounced percentage change in the expected direction for Anxiety than Moving Art (mean difference = 3.32; p = 0.003). The association between motivation and performance was non-significant. Based on these results we conclude that feedback with both negative and positive operant conditioning and emotion evoking effects should be preferred.
