Intensive-neurofeedback Protocol for Children With ADHD: A Proof-of-concept Study Comparing iAPF-personalized and Standard Theta-beta-ratio Training

The first aim of this clinical trial is to test the feasibility and signal validity of a new approach to neurofeedback training (NF) using intensive EEG-based theta-beta NF for children with ADHD in the context of NF camps during school holidays. The second aim is to compare the efficacy of two neurofeedback protocols in reducing ADHD symptoms. Previous study results highlight that children with ADHD frequently show increased Theta-Beta-Ratios (TBR) in the qEEG, probably associated with attention difficulties, which may be ameliorated following neurofeedback training. However, the current state of research shows heterogenous findings regarding the efficacy of standard TBR NF for children with ADHD. Further study results suggest that personalized NF training protocols, based on the individual alpha peak frequency (iAPF), may be more effective in reducing ADHD symptoms than standardized ones. Therefore, in this proof-of-concept study of children with ADHD a standard TBR NF protocol is compared with an iAPF-personalized TBR NF (iAPF-TBR NF) protocol (based on the previously obtained iAPF). The study is designed as a randomized controlled intervention trial (RCT) with three assessment points (pre \[T1\], post \[T2\] and 6-month follow-up \[T3\]). Primary endpoints include the reduction of ADHD symptoms assessed by parent-, teacher- and self-report questionnaires. Furthermore, it is hypothesized that NF training is associated with better performance in a sustained attention and executive function test and a reduced TBR in qEEG, particularly following iAPF-TBR NF. The main questions are: * Is it feasible to train groups of up to 12 children with two sessions NF per day for an eight-day-period during their school holidays? * Does iAPF-TBR NF provide a valid neuromodulatory signal compared to the standard-TBR-NF protocol? Do the frequency boundaries demonstrate spectral stability across the 16 training sessions? * Does the personalized iAPF-TBR NF training reduce ADHD symptoms measured immediately after the training more than standard-TBR-NF training? (comparison T2-T1) * Does the personalized iAPF-TBR NF training reduce ADHD symptoms measured 6 months after the NF training more than standard TBR-NF training? (comparison T3-T1) * Does the reduction in ADHD symptoms measured immediately after the NF-training persist until the 6-month follow-up? Do possible differences between iAPF-TBR NF training and standard TBR NF training remain? (comparison T3-T2) Post-hoc analyses of the courses are carried out. In addition, selectivity analyses will be carried out for clinical subgroups (e.g. different ADHD profiles)