Alpha Down-Regulation Neurofeedback_Its Effects on Short Term Memory and Learning Predictors

Abstract

Regulation of brain activity by neurofeedback training has been widely applied in treatment of human psychological disorders, improvement of human cognitive performance and recently enhancement of brain-computer interfaces (BCIs) performance. Nevertheless, different people possess different ability in learning how to regulate the brain activity by neurofeedback. On the other hand, no study has investigated whether the same EEG feature but with different training direction has the reverse effects on some performance. Regarding alpha neurofeedback, it has been demonstrated that up-regulation alpha neurofeedback has positive effects on short term memory enhancement and more interestingly that resting alpha activity can predict learning ability in up-regulation alpha neurofeedback. However, it is unknown whether down-regulation alpha neurofeedback has side effects on short term memory and whether the learning ability in this neurofeedback can be predicted by resting alpha activity. Thus, this project was concentrated on the investigation on: 1) whether multi-session neurofeedback training can decrease alpha activity and its effects on other EEG bands; 2) whether resting alpha (or other frequency bands) can predict the learning ability in alpha down-regulation neurofeedback training; 3) Whether this neurofeedback training has side effects in cognitive test of short term memory.

A total of 19 subjects performed 10 sessions of individualized alpha down-regulation neurofeedback training and real-time EEG indices in baseline tests and training sessions were recorded. 14 out of total 19 subjects could decrease the training parameter, their individual alpha band (IAB), over training sessions. The learning ability was assessed by four indices. It was found that five EEG indices (IAB, HIAB, alpha, beta and individual theta) from initial baseline before neurofeedback training (BL1) can predict the learning ability in alpha down-regulation neurofeedback training. The finding of predictors would be beneficial in looking for crux of and preventing frustration from non-learners. Moreover, it would help to improve the efficiency in further neurofeedback studies and enhance the performance for learners. In terms of the cognitive performance, no significant change in short term memory was observed before and after the alpha down-regulation neurofeedback training, indicating that this type of training has no side effects in short term memory.