Objective and Subjective Evaluation of Neurofeedback Trainings in Nonclinical Individuals

Neurofeedback training aims to teach self-regulation through signals derived from neural activity. In children with attention-deficit hyperactivity disorder, neurofeedback generally focuses on increasing the power of either the beta1 (15–18 Hz) or the sensory motor rhythm (12–15 Hz), while decreasing the power of other frequency bands. The purpose of this study was to evaluate the efficacy of objective and subjective measures for assessing the effects of neurofeedback training in nonclinical adults. We evaluated the effects of eight sessions of beta1 and sensory motor rhythm neurofeedback training in nonclinical adults using objective measures (i.e., event-related potential components during a flanker task) and subjective measures (i.e., Student Behavior Checklist). Sixteen adults were divided into beta1 and sensory motor rhythm training groups. An event-related potential component, N2, was enhanced at post-training compared with pre-training periods. Moreover, we observed enhanced N2 in the beta1 group, suggesting that improved attentional function influenced the N2 component. Conversely, we found no differences in the Student Behavior Checklist between the pre- and post-training periods for either group. These findings demonstrate that subjective measures were not sufficient to uncover the effects of eight neurofeedback training sessions. Thus, we suggest that objective measures, such as event-related potential components, be used to evaluate the effects of neurofeedback training.