[Comparison of learning and concentration effects of "knowledge of results (KR)" in alpha-wave feedback training]

Effects of KR on biofeedback have conventionally been limited by learning factor. The effects of feedback on an increase in EEG alpha have been believed to be so limited as well. However, the effects of KR are also believed to include factors such as motivation and concentration. In this study, the tendencies for alpha rhythm to change were analysed and compared under 3 different KR conditions in order to demonstrate the existence of the later factors. Effects of two parameters, alpha index and microvolt integral value, were also compared. The KR conditions consisted of three types with regard to an increase in alpha rhythm: true-KR, false-KR, and mixed-KR. Ten female college students underwent the feedback task for 10 minutes under each condition. It was shown that (1) the degree of achievement and temporal profile under three KR conditions demonstrated the involvement of learning factor as well as motivation and concentration factors, and (2) alpha index showed the effects of learning, motivation and concentration in KR more distinctly than the microvolt integral value.