The time-course of alpha neurofeedback training effects in healthy participants.

The time-course of alpha neurofeedback training (NFT) was investigated in 18 healthy participants who received 15 sessions of training (eyes open), each consisting of three training periods (data are from Van Boxtel et al., 2012). Here we report on the within- and between-session training effects using multilevel analyses. Over sessions, total alpha power (8-12 Hz) increased up to the tenth session, after which low alpha power (8-10 Hz) remained at the same level, while high alpha power (10-12 Hz) decreased. Within each training session, total alpha power increased from the first to the second period, and then decreased again. This decrease, however, was caused by a decrease in high alpha power only; low alpha power remained up to the end of training. These effects are discussed in terms of attention and motivation, and suggest different trainability for low and high alpha power.