The Relative Efficacy of Connectivity Guided and Symptom Based EEG Biofeedback for Autistic Disorders

Behavioral effect of mismatch negativity neurofeedback on foreign language learning

Listening is critical for foreign language learning. Listening difficulties can occur because of an inability to perceive or recognize sounds while listening to speech, whereas successful listening can boost understanding and improve speaking when learning a foreign language. Previous studies in our laboratory revealed that EEG-neurofeedback (NF) using mismatch negativity event-related brain potential successfully induced unconscious learning in terms of auditory discrimination of speech sounds. Here, we conducted a feasibility study with a small participant group (NF group and control group; six participants each) to examine the practical effects of mismatch negativity NF for improving the perception of speech sounds in a foreign language. Native Japanese speakers completed a task in which they learned to perceive and recognize spoken English words containing the consonants "l" or "r". Participants received neurofeedback training while not explicitly attending to auditory stimuli. The results revealed that NF training significantly improved the proportion of correct in discrimination and recognition trials, even though the training time for each word pair was reduced to 20% of the training time reported in our previous study. The learning effect was not affected by training with three pairs of words with different vowels. The current results indicate that NF resulted in long-term learning that persisted for at least 2 months.

The Effectiveness of Neurofeedback Therapy as an Alternative Treatment for Autism Spectrum Disorders in Children

Abstract. Findings for the effectiveness of neurofeedback in autism spectrum disorder are found to be inconsistent. Therefore, this review comprehensively and systematically reviewed literature on the effectiveness of neurofeedback for the treatment of autism spectrum disorders in children. A systematic search of Embase, Medline, Web of Science, PsycINFO, Cochrane, and Google Scholar was carried out in October 2017 to find relevant papers. We selected full journal articles that reported neurofeedback as a treatment for autism in children (0–17 years). The search yielded 587 articles and we included 20 references with a total of 443 participants. Ninety-four percent of nonrandomized controlled and experimental trials concerning neurofeedback for autism spectrum disorders found positive results. The evidence for effectiveness of neurofeedback therapy was even more robust when only randomized controlled studies were considered. Although there are only a few randomized controlled studies, results support effectiveness of neurofeedback for autism spectrum disorder, including long-term positive effects. In the future, optimal treatment protocols have to be developed to guide clinicians in their neurofeedback treatment. In conclusion, neurofeedback seems to be an alternative treatment for autism spectrum disorders, with space for improvement.

Changes in EEG Recordings in COVID-19 Patients as a Basis for More Accurate QEEG Diagnostics and EEG Neurofeedback Therapy: A Systematic Review

INTRODUCTION AND PURPOSE

The SARS-CoV-2 virus is able to cause abnormalities in the functioning of the nervous system and induce neurological symptoms with the features of encephalopathy, disturbances of consciousness and concentration and a reduced ability to sense taste and smell as well as headaches. One of the methods of detecting these types of changes in COVID-19 patients is an electroencephalogram (EEG) test, which allows information to be obtained about the functioning of the brain as well as diagnosing diseases and predicting their consequences. The aim of the study was to review the latest research on changes in EEG in patients with COVID-19 as a basis for further quantitative electroencephalogram (QEEG) diagnostics and EEG neurofeedback training. Description of the state of knowledge: Based on the available scientific literature using the PubMed database from 2020 and early 2021 regarding changes in the EEG records in patients with COVID-19, 17 publications were included in the analysis. In patients who underwent an EEG test, changes in the frontal area were observed. A few patients were not found to be responsive to external stimuli. Additionally, a previously non-emerging, uncommon pattern in the form of continuous, slightly asymmetric, monomorphic, biphasic and slow delta waves occurred.

CONCLUSION

The results of this analysis clearly indicate that the SARS-CoV-2 virus causes changes in the nervous system that can be manifested and detected in the EEG record. The small number of available articles, the small number of research groups and the lack of control groups suggest the need for further research regarding the short and long term neurological effects of the SARS-CoV-2 virus and the need for unquestionable confirmation that observed changes were caused by the virus per se and did not occur before. The presented studies described non-specific patterns appearing in encephalograms in patients with COVID-19. These observations are the basis for more accurate QEEG diagnostics and EEG neurofeedback training.

19 Channel Z-Score and LORETA Neurofeedback: Does the Evidence Support the Hype?

Neurofeedback is a well-investigated treatment for ADHD and epilepsy, especially when restricted to standard protocols such as theta/beta, slow cortical potentials and sensori-motor rhythm neurofeedback. Advances in any field are welcome and other techniques are being pursued. Manufacturers and clinicians are marketing ‘superior’ neurofeedback approaches including 19 channel Z-score neurofeedback (ZNFB) and 3-D LORETA neurofeedback (with or without Z-scores; LNFB). We conducted a review of the empirical literature to determine if such claims were warranted. This review included the above search terms in Pubmed, Google scholar and any references that met our criteria from the ZNFB publication list and was restricted to group based studies examining improvement in a clinical population that underwent peer review (book chapters, magazine articles or conference presentations are not included since these are not peer reviewed). Fifteen relevant studies emerged with only six meeting our criterion. Based on review of these studies it was concluded that empirical validation of these approaches is sorely lacking. There is no empirical data that supports the notion that 19-channel z-score neurofeedback is effective or superior. The quality of studies for LNFB was better compared to ZNFB and some suggestion for efficacy was demonstrated for ADHD and Tinnitus distress. However, these findings need to be replicated, extended to other populations and have yet to show any “superiority.” Our conclusions continue to emphasize the pervasive lack of evidence supporting these approaches to neurofeedback and the implications of this are discussed.

Attention, Executive Function, Behavior, and Electrocortical Function, Significantly Improved With 19-Channel Z-Score Neurofeedback in a Clinical Setting: A Pilot Study

OBJECTIVE

Neurofeedback (NF) is gaining recognition as an evidence-based intervention grounded in learning theory, and 19-channel z-score NF (19ZNF) is a new NF model. This pilot study sought to evaluate the efficacy of 19ZNF in a clinical setting.

METHOD

Outcome measures framed groups such that 19ZNF was evaluated, as it relates to the neuropsychological constructs of attention ( n = 10), executive function ( n = 12), behavior ( n = 14), and electrocortical functioning ( n = 21). One-tailed t tests compared pre-post difference scores.

RESULTS

For all pre-post comparisons, the direction of change was in the predicted direction, and differences were statistically significant ( p = .000 to p = .008, effect sizes 1.29 to 3.42).

CONCLUSION

Results suggest 19ZNF improved attention, executive function, behavior, and electrocortical function. This study provides beginning evidence of 19ZNF's efficacy, adds to what is known about 19ZNF, and offers an innovative approach for using quantitative electroencephalographic (QEEG) metrics as outcome measures.

Four Channel Multivariate Coherence Training: Development and Evidence in Support of a New Form of Neurofeedback

As the field of neurofeedback and neuromodulation grows, trends toward using neurofeedback to treat problems of brain dysfunction have emerged. While the use of connectivity based fMRI guided neurofeedback has shown itself to be efficacious, the expense related to the treatment calls for a more practical solution. The use of QEEG guided neurofeedback in the treatment has shown promise as an emerging treatment. To date, EEG based neurofeedback approaches have used technology with limited sophistication. We designed a new form of neurofeedback that uses four channels of EEG with a multivariate calculation of coherence metrics. Following a mathematical presentation of this model, we present findings of a multi-site study with clinical subjects with various diagnoses. We compared this form of multivariate coherence neurofeedback to the more standard two channel coherence training. Findings showed that there was a significant difference between the groups with four channel multivariate coherence neurofeedback leading to greater changes in EEG metrics. Compared to two channel coherence training, four channel multivariate coherence neurofeedback led to a greater than 50% change in power and 400% in coherence values per session. The significance of these findings is discussed in relation to complex calculations of effective connectivity and how this might lead to even greater enhancements in neurofeedback efficacy.

Child attachment and sensory regulation in psychiatric clinic-referred preschoolers

BACKGROUND

Individuals with sensory regulation disorders present with many difficulties in terms of managing emotions, behavior, and motor control. Children with such difficulties are often referred to psychiatric clinics for assessment of their behavioral and emotional problems. Few studies have investigated the role of environmental factors on sensory dysfunctions, and none have specifically studied its association with child attachment in a clinical sample.

OBJECTIVE

In this cross-sectional study, we examined the association between sensory regulation and child attachment among preschoolers referred to a psychiatric clinic.

METHOD

A sample of 60 preschoolers and their mothers were recruited through a child psychiatric clinic. Child attachment was assessed with the gold standard separation-reunion procedure for preschoolers. Parents completed the sensory profile, which assesses the presence of child hypersensitivity (sensitivity and avoidant scale) and hyposensitivity (sensory seeking and registration scale).

RESULTS

Data showed that 57% of the children were presented with clinical symptoms of sensory regulation. In addition, 53% of the children were classified insecure behaviorally disorganized or insecure disorganized controlling. In particular, results revealed that children classified as insecure disorganized controlling were significantly more likely to show hypersensitivity avoidance and sensory-seeking behaviors.

CONCLUSION

This study underscores the importance of the parent-child relationship for children with sensory regulation difficulties.

Relative Power of Specific EEG Bands and Their Ratios during Neurofeedback Training in Children with Autism Spectrum Disorder

Neurofeedback is a mode of treatment that is potentially useful for improving self-regulation skills in persons with autism spectrum disorder. We proposed that operant conditioning of EEG in neurofeedback mode can be accompanied by changes in the relative power of EEG bands. However, the details on the change of the relative power of EEG bands during neurofeedback training course in autism are not yet well explored. In this study, we analyzed the EEG recordings of children diagnosed with autism and enrolled in a prefrontal neurofeedback treatment course. The protocol used in this training was aimed at increasing the ability to focus attention, and the procedure represented the wide band EEG amplitude suppression training along with upregulation of the relative power of gamma activity. Quantitative EEG analysis was completed for each session of neurofeedback using wavelet transform to determine the relative power of gamma and theta/beta ratio, and further to detect the statistical changes within and between sessions. We found a linear decrease of theta/beta ratio and a liner increase of relative power of gamma activity over 18 weekly sessions of neurofeedback in 18 high functioning children with autism. The study indicates that neurofeedback is an effective method for altering EEG characteristics associated with the autism spectrum disorder. Also, it provides information about specific changes of EEG activities and details the correlation between changes of EEG and neurofeedback indexes during the course of neurofeedback. This pilot study contributes to the development of more effective approaches to EEG data analysis during prefrontal neurofeedback training in autism.

Neurofeedback and its possible relevance for the treatment of Tourette syndrome

Neurofeedback is an increasingly recognized therapeutic option in various neuropsychiatric disorders to treat dysfunctions in cognitive control as well as disorder-specific symptoms. In this review we propose that neurofeedback may also reflect a valuable therapeutic option to treat executive control functions in Gilles-de-la-Tourette syndrome (GTS). Deficits in executive control functions when ADHD symptoms appear in GTS likely reflect pathophysiological processes in cortico-thalamic-striatal circuits and may also underlie the motor symptoms in GTS. Such executive control deficits evident in comorbid GTS/ADHD depend on neurophysiological processes well-known to be modifiable by neurofeedback. However, so far efforts to use neurofeedback to treat cognitive dysfunctions are scarce. We outline why neurofeedback should be considered a promising treatment option, what forms of neurofeedback may prove to be most effective and how neurofeedback may be implemented in existing intervention strategies to treat comorbid GTS/ADHD and associated dysfunctions in cognitive control. As cognitive control deficits in GTS mostly appear in comorbid GTS/ADHD, neurofeedback may be most useful in this frequent combination of disorders.

Neuromodulation integrating rTMS and neurofeedback for the treatment of autism spectrum disorder: an exploratory study

Autism spectrum disorder (ASD) is a pervasive developmental disorder characterized by deficits in social interaction, language, stereotyped behaviors, and restricted range of interests. In previous studies low frequency repetitive transcranial magnetic stimulation (rTMS) has been used, with positive behavioral and electrophysiological results, for the experimental treatment in ASD. In this study we combined prefrontal rTMS sessions with electroencephalographic (EEG) neurofeedback (NFB) to prolong and reinforce TMS-induced EEG changes. The pilot trial recruited 42 children with ASD (~14.5 years). Outcome measures included behavioral evaluations and reaction time test with event-related potential (ERP) recording. For the main goal of this exploratory study we used rTMS-neurofeedback combination (TMS-NFB, N = 20) and waitlist (WTL, N = 22) groups to examine effects of 18 sessions of integrated rTMS-NFB treatment or wait period) on behavioral responses, stimulus and response-locked ERPs, and other functional and clinical outcomes. The underlying hypothesis was that combined TMS-NFB will improve executive functions in autistic patients as compared to the WTL group. Behavioral and ERP outcomes were collected in pre- and post-treatment tests in both groups. Results of the study supported our hypothesis by demonstration of positive effects of combined TMS-NFB neurotherapy in active treatment group as compared to control WTL group, as the TMS-NFB group showed significant improvements in behavioral and functional outcomes as compared to the WTL group.

Neurorehabilitation of social dysfunctions: a model-based neurofeedback approach for low and high-functioning autism

Autism Spectrum Disorder (ASD) is an increasingly prevalent condition with core deficits in the social domain. Understanding its neuroetiology is critical to providing insights into the relationship between neuroanatomy, physiology and social behaviors, including imitation learning, language, empathy, theory of mind, and even self-awareness. Equally important is the need to find ways to arrest its increasing prevalence and to ameliorate its symptoms. In this review, we highlight neurofeedback studies as viable treatment options for high-functioning as well as low-functioning children with ASD. Lower-functioning groups have the greatest need for diagnosis and treatment, the greatest barrier to communication, and may experience the greatest benefit if a treatment can improve function or prevent progression of the disorder at an early stage. Therefore, we focus on neurofeedback interventions combined with other kinds of behavioral conditioning to induce neuroplastic changes that can address the full spectrum of the autism phenotype.

Brain-computer interface game applications for combined neurofeedback and biofeedback treatment for children on the autism spectrum

Individuals with autism spectrum disorder (ASD) show deficits in social and communicative skills, including imitation, empathy, and shared attention, as well as restricted interests and repetitive patterns of behaviors. Evidence for and against the idea that dysfunctions in the mirror neuron system are involved in imitation and could be one underlying cause for ASD is discussed in this review. Neurofeedback interventions have reduced symptoms in children with ASD by self-regulation of brain rhythms. However, cortical deficiencies are not the only cause of these symptoms. Peripheral physiological activity, such as the heart rate and its variability, is closely linked to neurophysiological signals and associated with social engagement. Therefore, a combined approach targeting the interplay between brain, body, and behavior could be more effective. Brain–computer interface applications for combined neurofeedback and biofeedback treatment for children with ASD are currently nonexistent. To facilitate their use, we have designed an innovative game that includes social interactions and provides neural- and body-based feedback that corresponds directly to the underlying significance of the trained signals as well as to the behavior that is reinforced.

Neurofeedback training produces normalization in behavioural and electrophysiological measures of high-functioning autism

Autism spectrum disorder (ASD) is a neurodevelopmental condition exhibiting impairments in behaviour, social and communication skills. These deficits may arise from aberrant functional connections that impact synchronization and effective neural communication. Neurofeedback training (NFT), based on operant conditioning of the electroencephalogram (EEG), has shown promise in addressing abnormalities in functional and structural connectivity. We tested the efficacy of NFT in reducing symptoms in children with ASD by targeting training to the mirror neuron system (MNS) via modulation of EEG mu rhythms. The human MNS has provided a neurobiological substrate for understanding concepts in social cognition relevant to behavioural and cognitive deficits observed in ASD. Furthermore, mu rhythms resemble MNS phenomenology supporting the argument that they are linked to perception and action. Thirty hours of NFT on ASD and typically developing (TD) children were assessed. Both groups completed an eyes-open/-closed EEG session as well as a mu suppression index assessment before and after training. Parents filled out pre- and post-behavioural questionnaires. The results showed improvements in ASD subjects but not in TDs. This suggests that induction of neuroplastic changes via NFT can normalize dysfunctional mirroring networks in children with autism, but the benefits are different for TD brains.

Computational model of excitatory/inhibitory ratio imbalance role in attention deficit disorders

Impairments in attentional behaviors, including over-selectivity, under-selectivity, distractibility and difficulty in shift of attention, are widely reported in several developmental disorders, including autism. Uncharacteristic inhibitory to excitatory neuronal number ratio (IER) and abnormal synaptic strength levels in the brain are two broadly accepted neurobiological disorders observed in autistic individuals. These neurobiological findings are contrasting and their relation to the atypical attentional behaviors is not clear yet. In this paper, we take a computational approach to investigate the relation of imbalanced IER and abnormal synaptic strength to some well-documented spectrum of attentional impairments. The computational model is based on a modified version of a biologically plausible neural model of two competing minicolumns in IT cortex augmented with a simple model of top-down attention. Top-down attention is assumed to amplify (attenuates) attended (unattended) stimulus. The inhibitory synaptic strength parameter in the model is set such that typical attentional behavior is emerged. Then, according to related findings, the parameter is changed and the model's attentional behavior is considered. The simulation results show that, without any change in top-down attention, the abnormal inhibitory synaptic strength values--and IER imbalance- result in over-selectivity, under-selectivity, distractibility and difficulty in shift of attention in the model. It suggests that the modeled neurobiological abnormalities can be accounted for the attentional deficits. In addition, the atypical attentional behaviors do not necessarily point to impairments in top-down attention. Our simulations suggest that limited changes in the inhibitory synaptic strength and variations in top-down attention signal affect the model's attentional behaviors in the same way. So, limited deficits in the inhibitory strength may be alleviated by appropriate change in top-down attention biasing. Nevertheless, our model proposes that this compensation is not possible for very high and very low values of the inhibitory strength.

Intranasal oxytocin modulates EEG mu/alpha and beta rhythms during perception of biological motion

Oxytocin (OT) plays a determining role in social and pair bonding in many vertebrates and increasing evidence suggests it is a social hormone also in humans. Indeed, intranasal administration of OT modulates several social cognitive processes in humans. Electrophysiological studies in humans associated the suppression of EEG in the mu/alpha and beta bands with perception of biological motion and social stimuli. It has been suggested that mu and beta suppression over sensory-motor regions reflects a resonance system in the human brain analogous to mirror neurons in the monkey. We therefore hypothesized that OT, a social hormone, would enhance this suppression, hence, for the first time, link the action of this neuropeptide with a human correlate of mirror neuron activity. Twenty-four students were administered 24 IU of OT or placebo intranasally in a robust, double-blind within-subject design. 45 min later participants were shown a point-light display of continuous biological motion of a human figure's walk. In the 8-10 Hz (low alpha/mu band) and in the 15-25 Hz beta band, a significant main effect of treatment showed that suppression was significantly enhanced in the OT versus the placebo conditions and that this suppression was widespread across the scalp. These results are a first step linking OT to the modulation of EEG rhythms in humans, suggesting that OT may have a role in allocating cortical resources to social tasks partly mediated by mirror neuron activity.

Neurofeedback for autistic spectrum disorder: a review of the literature

There is a need for effective interventions to address the core symptoms and problems associated with autistic spectrum disorder (ASD). Behavior therapy improves communication and behavioral functioning. Additional treatment options include psychopharmacological and biomedical interventions. Although these approaches help children with autistic problems, they may be associated with side effects, risks or require ongoing or long-term treatment. Neurofeedback is a noninvasive approach shown to enhance neuroregulation and metabolic function in ASD. We present a review of the literature on the application of Neurofeedback to the multiple problems associated with ASD. Directions for future research are discussed.