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Contains fulltext : 247442.pdf (Publisher’s version ) (Open Access) Background: Attention-deficit/hyperactivity disorder is characterized by neurobiological heterogeneity, possibly explaining why not all patients benefit from a given treatment. As a means to select the right treatment (stratification), biomarkers may aid in personalizing treatment prescription, thereby increasing remission rates. Methods: The biomarker in this study was developed in a heterogeneous clinical sample (N=4249), and first applied to two large transfer datasets, a priori stratifying young males (

Attention-deficit/hyperactivity disorder (ADHD) is characterized by neurobiological heterogeneity, possibly explaining why not all patients benefit from a given treatment. As a means to select the right treatment (stratification), biomarkers may aid in personalizing treatment prescription, thereby increasing remission rates.The present study introduces a clinically interpretable and actionable, age- and sex-standardized biomarker based on individual alpha peak frequency (iAPF) assessed during resting-state electroencephalography (EEG). The biomarker was developed in a heterogeneous sample (N=4249), and stratifies patients with a higher iAPF to Methylphenidate (MPH; N=336) and those with a lower iAPF to Neurofeedback (NFB; N=136), resulting in a predicted gain in normalized remission of 17-30%. Blinded out-of-sample validation studies for MPH (N=58) and NFB (N=96) corroborated these findings, yielding a predicted gain in stratified normalized remission of 36% and 29%, respectively.These findings suggest that acknowledging neurobiological heterogeneity can inform stratification of patients to their individual best treatment and enhance remission rates.

Contains fulltext : 240290.pdf (Publisher’s version ) (Open Access) 1 p.

Background. This study reports on a new method for golf performance enhancement employing personalized real-life neurofeedback during golf putting. Method. Participants (n = 6) received an assessment and three real-life neurofeedback training sessions. In the assessment, a personal event-locked electroencephalographic (EEG) profile at FPz was determined for successful versus unsuccessful putts. Target frequency bands and amplitudes marking optimal prefrontal brain state were derived from the profile by two raters. The training sessions consisted of four series of 80 putts in an ABAB design. The feedback in the second and fourth series was administered in the form of a continuous NoGo tone, whereas in the first and third series no feedback was provided. This tone was terminated only when the participants EEG met the assessment-defined criteria. In the feedback series, participants were instructed to perform the putt only after the NoGo tone had ceased. Results. From the personalized event-locked EEG profiles, individual training protocols were established. The interrater reliability was 91%. The overall percentage of successful putts was significantly larger in the second and fourth series (feedback) of training compared to the first and third series (no feedback). Furthermore, most participants improved their performance with feedback on their personalized EEG profile, with 25% on average. Conclusions. This study demonstrates that the "zone" or the optimal mental state for golf putting shows clear recognizable personalized patterns. The learning effects suggest that this real-life approach to neurofeedback improves learning speed, probably by tapping into learning associated with contextual conditioning rather than operant conditioning, indicating perspectives for clinical applications. © 2007 by The Haworth Press.

Contains fulltext : 72797.pdf (Publisher’s version ) (Closed access) Background. Operant conditioning of one's slow cortical potential (SCP) or sensorimotor rhythm (SMR) can be used to control epilepsy or to manipulate external devices, as applied in BCI (Brain-Computer Interface). A commonly accepted view that both SCP and SMR are reflections of central arousal suggests a functional relationship between SCP and SMR networks. Method. The operant conditioning of SCP or SMR was tested with a single electroencephalographic (EEG) channel wireless biofeedback system. A series of trainings taught 19 participants to control SCP or SMR over vertex during 20 neurofeedback sessions. Each session consisted of 96 trials to decrease cortical arousal (SCP positivity/SMR enhancement) and 64 trials to increase cortical arousal (SCP negativity/SMR suppression). In each trial, participants were required to exceed an individual threshold level of the feedback parameter relative to a 500-msec prefeedback baseline and to hold this level for 2 sec (SCP) or 0.5 sec (SMR) to obtain reinforcement. Results. Ten of the 19 participants achieved control over their EEG. In the SCP-trained group, 4 of 9 participants increased the differentiation between their SCP responses on positivity-required versus negativity-required trials. SMR suppression and enhancement was achieved by 3 and 4 of the 10 SMR-trained participants. The SMR-trained responders did not show differentiation in their SMR responses, but did show a differentiation in their SCP response—while trained on SMR. Conclusions. The results showed the proposed method was successful to teach control of SCP or SMR. Bidirectional control was very difficult to achieve with the present SMR training procedure. SCP positivity and SMR enhancement were easier to learn. The results suggest that SMR training modulates excitability thresholds in the striatal-thalamocortical motor loop, whereas changes in the loop's excitability thresholds by SCP training do not affect the thalamic bursting that underlies the SMR. 18 p.

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Aims: QEEG and neuropsychological tests were used to investigate the underlying neural processes in dyslexia. Methods: A group of dyslexic children were compared with a matched control group from the Brain Resource International Database on measures of cognition and brain function (EEG and coherence). Results: The dyslexic group showed increased slow activity (Delta and Theta) in the frontal and right temporal regions of the brain. Beta-1 was specifically increased at F7. EEG coherence was increased in the frontal, central and temporal regions for all frequency bands. There was a symmetric increase in coherence for the lower frequency bands (Delta and Theta) and a specific right-temporocentral increase in coherence for the higher frequency bands (Alpha and Beta). Significant correlations were observed between subtests such as Rapid Naming Letters, Articulation, Spelling and Phoneme Deletion and EEG coherence profiles. Discussion: The results support the double-deficit theory of dyslexia and demonstrate that the differences between the dyslexia and control group might reflect compensatory mechanisms. Integrative Significance: These findings point to a potential compensatory mechanism of brain function in dyslexia and helps to separate real dysfunction in dyslexia from acquired compensatory mechanisms.

Item does not contain fulltext New treatments for Alzheimer's disease require early detection of cognitive decline. Most studies seeking to identify markers of early cognitive decline have focused on a limited number of measures. We sought to establish the profile of brain function measures which best define early neuropsychological decline. We compared subjects with subjective memory complaints to normative controls on a wide range of EEG derived measures, including a new measure of event-related spatio-temporal waves and biophysical modeling, which derives anatomical and physiological parameters based on subject's EEG measurements. Measures that distinguished the groups were then related to cognitive performance on a variety of learning and executive function tasks. The EEG measures include standard power measures, peak alpha frequency, EEG desynchronization to eyes-opening, and global phase synchrony. The most prominent differences in subjective memory complaint subjects were elevated alpha power and an increased number of spatio-temporal wave events. Higher alpha power and changes in wave activity related most strongly to a decline in verbal memory performance in subjects with subjective memory complaints, and also declines in maze performance and working memory reaction time. Interestingly, higher alpha power and wave activity were correlated with improved performance in reverse digit span in the subjective memory complaint group. The modeling results suggest that differences in the subjective memory complaint subjects were due to a decrease in cortical and thalamic inhibitory gains and slowed dendritic time-constants. The complementary profile that emerges from the variety of measures and analyses points to a nonlinear progression in electrophysiological changes from early neuropsychological decline to late-stage dementia, and electrophysiological changes in subjective memory complaint that vary in their relationships to a range of memory-related tasks. 26 p.

The scores of 78 bulimia nervosa (BN) patients and 67 general psychiatric outpatients on the Revised Eating Disorder Inventory (EDI-2) were compared in a multivariate discriminant analysis. The bulimia scale was found to correctly classify 97 per cent of all cases. Of the EDI-2 scales thought to be not directly related to food and weight, only interoceptive awareness (IA) and asceticism (AS) showed discriminative validity. Three eating-related items were found to account for the discriminative value of the IA scale, and the new AS scale was found to be a discriminative extension of the EDI.

A wide variety in outcome criteria hinders comparison of results between smoking cessation studies. Three important methodological issues are discussed: analysis of data of participants who drop out of therapy, treatment of missing data, and repeated use of significance tests. These issues determine to a great extent the results of evaluation studies. In general, they are of interest to all researchers of addiction who study the effects of interventions. Several ways to decide on these issues and the consequences of these decisions are considered. Little consensus exists about the criterion for dropout. It is concluded that a dropout criterion is a burden rather than a help. A better criterion would be the number of sessions present. Few satisfying techniques exist to handle the problem of missing data. Evaluation studies need to set a priori standards to counter the increased risk of a Type I error, caused by the repeated use of significance tests. Reviewers need to be aware of the variety in data treatment before comparing results.