Slow cortical potentials neurofeedback in children with ADHD: comorbidity, self-regulation and clinical outcomes 6 months after treatment in a multicenter randomized controlled trial.

Despite sizeable short-term effects of neurofeedback (NF) therapy on attention-deficit and hyperactivity disorder (ADHD), longer-term clinical, comorbidity and self-regulation outcomes are less systematically studied. The aim of this largest NF follow-up to date was to evaluate these outcomes 6 months after NF compared to a semi-active control to disentangle specific from unspecific sustained effects. We performed a multicenter, randomized, parallel, controlled, clinical, superiority trial in five German university outpatient departments. Participants were eligible if they fulfilled DSM-IV-TR criteria for ADHD and were aged from 7 to 9 years. Participants were randomly assigned (1:1-ratio) to 25 sessions of slow cortical potential (SCP)-NF or electromyogram biofeedback (EMG-BF). Participants were not blinded, since they received instructions according to each treatment setting. Primary outcomes were parent ratings of ADHD. The trial was registered, number ISRCTN761871859. Both groups showed improvement of ADHD symptoms compared to baseline at 6-months follow-up with large effect sizes for SCP-NF (d = 1.04) and EMG-BF (d = 0.85), but without group differences. When analyzing all assessments (pre-test, post-test-1, post-test-2 and follow-up), a group-by-time interaction emerged (p = 0.0062), with SCP-NF showing stable improvement following treatment but EMG-BF showing a relapse from post-test-1 to post-test-2, and subsequent remission at follow-up. Six months after the end of treatment, improvement after SCP-NF remained large and stable. However, the lack of group differences at follow-up suggests shared specific and unspecific effects contributing to this clinical outcome. Our correlational results indicate specificity of SCP-NF for selected subscales after training, but not at follow-up.

BDNF Val66Met and reward-related brain function in adolescents: role for early alcohol consumption.

Changes in reward processing have been identified as one important pathogenetic mechanism in alcohol addiction. The nonsynonymous single nucleotide polymorphism in the brain-derived neurotrophic factor (BDNF) gene (rs6265/Val66Met) modulates the central nervous system activity of neurotransmitters involved in reward processing such as serotonin, dopamine, and glutamate. It was identified as crucial for alcohol consumption in healthy adults and, in rats, specifically related to the function in the striatum, a region that is commonly involved in reward processing. However, studies in humans on the association of BDNF Val66Met and reward-related brain functions and its role for alcohol consumption, a significant predictor of later alcohol addiction, are missing. Based on an intermediate phenotype approach, we assessed the early orientation toward alcohol and alcohol consumption in 530 healthy adolescents that underwent a monetary incentive delay task during functional magnetic resonance imaging. We found a significantly lower response in the putamen to reward anticipation in adolescent Met carriers with high versus low levels of alcohol consumption. During reward feedback, Met carriers with low putamen reactivity were significantly more likely to orient toward alcohol and to drink alcohol 2 years later. This study indicates a possible effect of BDNF Val66Met on alcohol addiction-related phenotypes in adolescence.