Comparing tomographic EEG neurofeedback and EMG biofeedback in children with attention-deficit/hyperactivity disorder.

Two types of biofeedback (BF), tomographic electroencephalogram (EEG) neurofeedback (NF) and electromyographic biofeedback (EMG-BF), both with phasic and tonic protocols, were compared for treatment effects and specificity in attention-deficit/hyperactivity disorder (ADHD). Thirteen children with ADHD trained their brain activity in the anterior cingulate cortex (ACC), and twelve trained activity of arm muscles involved in fine motor skills. In each training session, resting state 24-channel EEG and training performances were recorded. Both groups showed similar behavioral improvements and artifact reduction in selected conditions, with no significant advantages despite medium effect sizes on primary outcomes for NF. Only the EMG-BF group, however, showed clear improvement in training regulation performance, and specific motor coordination effects. The NF group tended to present individual normalization of trained frequency bands in the ACC during rest across training. The results provide evidence for some specific effects in our small sample, albeit only to a small extent.

Maurizio S ，Liechti MD ，Heinrich H ，Jäncke L ，Steinhausen HC ，Walitza S ，Brandeis D ，Drechsler R ... -  《-》

Differential EMG biofeedback for children with ADHD: a control method for neurofeedback training with a case illustration.

Maurizio S ，Liechti MD ，Brandeis D ，Jäncke L ，Drechsler R ... -  《-》

First clinical trial of tomographic neurofeedback in attention-deficit/hyperactivity disorder: evaluation of voluntary cortical control.

Tomographic neurofeedback (tNF) training was evaluated as a treatment for attention-deficit/hyperactivity disorder (ADHD). To investigate the specificity of the treatment, outcomes were related to learning during tNF. Thirteen children with ADHD trained over 36 lessons to regulate their brain activity in the anterior cingulate cortex (ACC) using both theta-beta frequency and slow cortical potential (SCP) protocols. Thirty-channel electroencephalogram (EEG) was used to calculate low-resolution electromagnetic tNF and to assess the course of the training. Pre- and post-assessments included questionnaires, tests of attention, EEG recordings, and cognitive event-related potentials. Despite behavioural improvement and EEG artefact reduction, only partial learning was found for ACC parameters. Successful regulation was observed only for a simple feedback variant of SCP training, but with ACC-specific effects. Over training, resting EEG analysis indicated individual frequency normalisation rather than unidirectional changes across subjects. These results indicate that clinical improvement after ACC-tNF training can parallel artefact reduction without substantial learning of improved cortical control. However, individual normalisation of resting EEG activity and partial SCP control proved possible in this specific brain region affected in ADHD using tNF. Further studies are needed to clarify which critical aspects mediate region-specific learning in neurofeedback. This study is the first to systematically investigate tNF in children suffering from a psychiatric disorder.

Liechti MD ，Maurizio S ，Heinrich H ，Jäncke L ，Meier L ，Steinhausen HC ，Walitza S ，Drechsler R ，Brandeis D ... -  《-》

EMG biofeedback training in adult attention-deficit/hyperactivity disorder: An active (control) training?

The present study aimed at revealing neurophysiological effects induced by electromyography (EMG) based biofeedback, considered as a semi-active control condition in neurofeedback studies, in adult attention-deficit/hyperactivity disorder (ADHD) patients. 20 adult ADHD patients trained their muscle activity in the left and right supraspinatus muscle over the course of 30 EMG biofeedback sessions. Changes induced by the EMG feedback were evaluated at a clinical and neurophysiological level; additionally, the relation between changes in EEG activity recorded at the vertex over the training course and changes of symptom severity over the treatment course were assessed in order to investigate the mechanisms underlying clinical effects of EMG biofeedback. Participants showed significant behavioral improvements on a self-rating scale. There was a significant increase in alpha power, but no significant changes in the delta frequency range; changes in the theta and beta frequency range were not significant after adjustment for multiple comparisons. No statistically significant correlation was found between changes in EEG frequency bands and changes in ADHD symptoms. The current results assessed by means of a single-electrode EEG constitute a starting point regarding a clearer understanding of mechanisms underlying clinical effects of EMG biofeedback. Although we did not reveal systematic effects induced by EMG feedback on brain activity it remains an open question whether EMG biofeedback induces changes in brain regions or parameters we did not gather in the present study (e.g. motor cortex).

Barth B ，Mayer K ，Strehl U ，Fallgatter AJ ，Ehlis AC ... -  《-》

Distinct EEG effects related to neurofeedback training in children with ADHD: a randomized controlled trial.

Gevensleben H ，Holl B ，Albrecht B ，Schlamp D ，Kratz O ，Studer P ，Wangler S ，Rothenberger A ，Moll GH ，Heinrich H ... -  《-》