Modulation of Intrinsic Brain Connectivity by Implicit Electroencephalographic Neurofeedback

The effects of neurofeedback training on behavior and brain functional networks in children with autism spectrum disorder

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder with an unclear pathogenesis to date. Neurofeedback (NFB) had shown therapeutic effects in patients with ASD. In this study,we analyzed the brain functional networks of children with ASD and investigated the impact of NFB targeting the beta rhythm training on these networks. The Autism Behavior Checklist (ABC) and Social Response Scale (SRS) were employed to evaluate the effects of NFB training on the behavioral abilities of children with ASD. We compared the differences in static and dynamic brain functional networks between ASD and Typically Developing (TD) children, also explored the changes in these networks in ASD children after 20 sessions of NFB training. The Weighted Phase Lag Index (wPLI) was used to construct static functional networks, and the Fuzzy Entropy (FuzzyEn) algorithm was further employed to measure the complexity of static functional connectivity and construct dynamic functional networks. This allowed the analysis of functional connectivity and fluctuations in the static functional networks of ASD and TD children, as well as the time variability of the dynamic functional networks. Additionally, the study explored the changes in brain functional networks and behavioral scales before and after NFB training. Results from behavioral scales indicated significant improvements in cognitive, communication, language, and social scores in ASD children following NFB intervention. EEG analysis revealed that static functional connectivity was lower, connectivity variability was higher, and temporal variability was greater in ASD children compared to TD children. Following NFB training, increased functional connectivity, reduced connectivity variability in the Delta frequency band, and decreased temporal variability were observed in ASD children. The results revealed abnormalities in both static and dynamic functional networks in children with ASD, with NFB training showed potential to modulate these networks. While our results showed that NFB training can assist participants in regulating connectivity and temporal variability in specific brain regions, robust evidence for its effectiveness in alleviating core symptoms of ASD remained limited.

Role of the insula in rTMS response for depression

BACKGROUND

The insula has a significant impact on interoception and depression. This study aims to explore the role of the insula in mediating treatment responses to high-frequency repetitive transcranial magnetic stimulation (rTMS) targeting the left dorsolateral prefrontal cortex (DLPFC).

METHODS

Twenty-five patients with either bipolar disorder (BD, n = 15) or major depressive disorder (MDD, n = 10) were recruited. All subjects were aged between 20 and 70, with a minimum score of 18 on the 24-item Hamilton Rating Scale for Depression (HDRS-24). Each patient received 12 sessions of rTMS treatment using a figure-eight-shaped coil at 10 Hz high-frequency stimulation intensity, targeted to the left DLPFC. Resting-state functional magnetic resonance imaging was conducted before and after the rTMS treatment to assess changes in insula-seeded functional connectivity.

RESULTS

Both BD and MDD patients experienced significant reductions in depressive symptoms following rTMS therapy. The respective response rates at weeks 4, 8 and 12 were 64.0 %, 64.0 % and 68.0 % and remission rates were 40.0 %, 36.0 % and 44.0 %. Decreases in functional connectivity between the right anterior insula and right calcarine were significantly larger in the remitters than in the non-remitters (p = 0.013). Additionally, a higher baseline functional connectivity between the right anterior insula and right superior temporal gyrus correlated with better treatment outcome.

LIMITATIONS

The small sample size of 25 participants is small.

CONCLUSION

Our findings highlight the potential role of the insula in depression and suggest that insula-seeded functional connectivity could serve as a predictive biomarker for rTMS efficacy.

Alexithymia: Toward an Experimental, Processual Affective Science with Effective Interventions

Alexithymia is a multi-dimensional personality trait involving difficulty identifying feelings, difficulty describing feelings, and an externally oriented thinking style. Poor fantasy life is debated as another facet. For over 50 years, the alexithymia literature has examined how alexithymia-related disturbances in perceiving and expressing feelings contribute to mental and physical disorders. We review the current understanding of alexithymia-including its definition, etiology, measurement, and vulnerabilities for both mental and physical illness-and its treatment. We emphasize the importance of further experimental and processual affective science research that (a) emphasizes facet-level analysis toward an understanding of the nuanced bases of alexithymia effects on neural, cognitive, and behavioral processes; (b) distinguishes between emotion deficits and emotion over-responding, including when over-responding is functional; and (c) clarifies when and how impairments occur for neutral and positively valenced information or contexts. Taken as a whole, a clarification of these issues will provide clear directions for effective and tailored alexithymia interventions.

Neurofeedback Recuperates Cognitive Functions in Children with Autism Spectrum Disorders (ASD)

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impaired social interaction, verbal and nonverbal communication, and behaviors or interests. Besides behavioral, psychopharmacological and biomedical interventions there is increasing evidence of non-invasive treatments like neurofeedback (NFB) that can improve brain activity. In this study, we have investigated whether NFB can improve cognitive functions in children with ASD. Thirty-five children with ASD (7-17 years) were selected by purposive sampling. The subjects underwent 30 sessions of NFB training for 20 min over 10 weeks' period. Psychometric tests i.e. Childhood Autism Rating Scale (CARS), IQ scoring and Reward sensitivity tests were administered at baseline. Pre and post NFB intervention assessment of executive functions, working memory and processing speed were done by NIH Toolbox Cognition Batteries. Friedman test revealed that children showed a statistically significant improvement in the NIH Tool Box cognitive assessments, including the Flankers Inhibitory Control and Attention Test (Pre-test = 3.63, Post-test = 5.22; p = 0.00), the Dimensional Change Card Sorting Test (Pre-test = 2.88, Post-test = 3.26; p = 0.00), the Pattern Comparison Processing Speed Test (Pre-test = 6.00, Post-test = 11:00; p = 0.00) and the List Sorting Working Memory Test (Pre-test = 4.00, Post-test = 6:00; p = 0.00), and displayed a trend of improvement at 2-month follow-up (Flankers Inhibitory Control and Attention Test (Post-test = 5.11 ± 2.79, Follow-Up = 5.31 ± 2.67; p = 0.21), the Dimensional Change Card Sorting Test (Post-test = 3.32 ± 2.37, Follow-Up = 3.67 ± 2.35; p = 0.054), the Pattern Comparison Processing Speed Test (Post-test = 13.69 ± 9.53, Follow-Up = 14.42 ± 10.23 p = 0.079) and the List Sorting Working Memory Test (Post-test = 6.17 ± 4.41, Follow-Up = 5.94 ± 4.03; p = 0.334). Our findings suggest NFB intervention for 10 weeks produce improvement in executive functions (Inhibitory Control and Attention and Cognitive Flexibility), Processing Speed and Working Memory in ASD Children.

The potential of infra-low frequency neurofeedback training in peak performance: The first double-blinded placebo-controlled longitudinal study in healthy adults

Infra-low frequency neurofeedback training (ILF-NFT) has shown promise in addressing cognitive and affective distress symptoms across a range of psychiatric disorders. This study tested ILF-NFT's effects in a double-blinded, placebo-controlled longitudinal context in healthy psychology students. Across five weeks, forty-two healthy psychology students (aged 18-35) were randomly allocated into two groups, receiving ten sessions of 30 minutes of active and sham ILF-NFT. Dependent variables were measured before, following, and two months after the intervention and were comprised of: heartrate variability assessments as a measure of stress resilience; digit span, n-back, trail making and go-no-go task measures of executive functioning performance; and SCL-90-R, WHOQOL-Bref, and peak performance measures of subjective self-report. Statistical analysis was performed using an ANCOVA and compared across groups correcting for baseline differences and multiple comparisons. ANCOVA analyses revealed no significant differences across active and placebo groups in any dependent variables, when correcting for multiple comparisons. Thus, the remaining analyses focused on questionnaire correlations. Here, significant correlations were observed between the novel peak performance questionnaire with the SCL-90-R and WHOQOL-Bref, confirming its construct and retest validity. Despite several methodological limitations, including a potential type-2 error, this study highlights limited effects of ILF-NFT in healthy volunteers. Future research should thus focus on clinically driven experimental designs to explore ILF-NFT's potential in psychiatric contexts. Further research utilization of the novel peak performance questionnaire is recommended for measures of peak performance.

Gait Training-Based Motor Imagery and EEG Neurofeedback in Lokomat: A Clinical Intervention With Complete Spinal Cord Injury Individuals

Robotic systems, such as Lokomat® have shown promising results in people with severe motor impairments, who suffered a stroke or other neurological damage. Robotic devices have also been used by people with more challenging damages, such as Spinal Cord Injury (SCI), using feedback strategies that provide information about the brain activity in real-time. This study proposes a novel Motor Imagery (MI)-based Electroencephalogram (EEG) Visual Neurofeedback (VNFB) system for Lokomat® to teach individuals how to modulate their own μ (8-12 Hz) and β (15-20 Hz) rhythms during passive walking. Two individuals with complete SCI tested our VNFB system completing a total of 12 sessions, each on different days. For evaluation, clinical outcomes before and after the intervention and brain connectivity were analyzed. As findings, the sensitivity related to light touch and painful discrimination increased for both individuals. Furthermore, an improvement in neurogenic bladder and bowel functions was observed according to the American Spinal Injury Association Impairment Scale, Neurogenic Bladder Symptom Score, and Gastrointestinal Symptom Rating Scale. Moreover, brain connectivity between different EEG locations significantly ( [Formula: see text]) increased, mainly in the motor cortex. As other highlight, both SCI individuals enhanced their μ rhythm, suggesting motor learning. These results indicate that our gait training approach may have substantial clinical benefits in complete SCI individuals.

Integrated use of biofeedback and neurofeedback techniques in treating pathological conditions and improving performance: a narrative review

In recent years, the scientific community has begun tо explore the efficacy оf an integrated neurofeedback + biofeedback approach іn various conditions, both pathological and non-pathological. Although several studies have contributed valuable insights into its potential benefits, this review aims tо further investigate its effectiveness by synthesizing current findings and identifying areas for future research. Our goal іs tо provide a comprehensive overview that may highlight gaps іn the existing literature and propose directions for subsequent studies. The search for articles was conducted on the digital databases PubMed, Scopus, and Web of Science. Studies to have used the integrated neurofeedback + biofeedback approach published between 2014 and 2023 and reviews to have analyzed the efficacy of neurofeedback and biofeedback, separately, related to the same time interval and topics were selected. The search identified five studies compatible with the objectives of the review, related to several conditions: nicotine addiction, sports performance, Autism Spectrum Disorder (ASD), and Attention Deficit Hyperactivity Disorder (ADHD). The integrated neurofeedback + biofeedback approach has been shown to be effective in improving several aspects of these conditions, such as a reduction in the presence of psychiatric symptoms, anxiety, depression, and withdrawal symptoms and an increase in self-esteem in smokers; improvements in communication, imitation, social/cognitive awareness, and social behavior in ASD subjects; improvements in attention, alertness, and reaction time in sports champions; and improvements in attention and inhibitory control in ADHD subjects. Further research, characterized by greater methodological rigor, is therefore needed to determine the effectiveness of this method and the superiority, if any, of this type of training over the single administration of either. This review іs intended tо serve as a catalyst for future research, signaling promising directions for the advancement оf biofeedback and neurofeedback methodologies.

Self-regulation training for people with knee osteoarthritis: a protocol for a feasibility randomised control trial (MiNT trial)

Introduction

Knee osteoarthritis (OA) is a chronic secondary musculoskeletal pain condition resulting in disability, reduced quality of life, and high societal costs. Pain associated with knee OA is linked to increased sensitivity in sensory, cognitive, and emotional areas of the brain. Self-regulation training targeting brain functioning related to pain experience could reduce pain and its associated disability. Self-regulatory treatments such as mindfulness meditation (MM) and electroencephalography neurofeedback (EEG-NF) training improve clinical outcomes in people with knee OA. A feasibility clinical trial can address factors that could inform the design of the full trial investigating the effectiveness of self-regulation training programmes in people with knee OA. This clinical trial will evaluate the feasibility, safety, acceptability, experience and perceptions of the self-regulatory training programmes.

Methods

The proposed feasibility trial is based on a double-blind (outcome assessor and investigators), three-arm (MM usual care, EEG-NF + usual care and usual care control group) randomised controlled parallel clinical trial. Participants with knee OA will be recruited from the community and healthcare practices. A research assistant (RA) will administer both interventions (20-min sessions, four sessions each week, and 12 sessions over three successive weeks). Feasibility measures (participant recruitment rate, adherence to interventions, retention rate), safety, and acceptability of interventions will be recorded. An RA blinded to the group allocation will record secondary outcomes at baseline, immediately post-intervention (4th week), and 3 months post-intervention. The quantitative outcome measures will be descriptively summarised. The qualitative interviews will evaluate the participants' experiences and perceptions regarding various aspects of the trial, which includes identifying the barriers and facilitators in participating in the trial, evaluating their opinions on the research procedures, such as their preferences for the study site, and determining the level of acceptability of the interventions as potential clinical treatments for managing knee OA. Māori participant perceptions of how assessment and training practices could be acceptable to a Māori worldview will be explored. The interviews will be audio-recorded and analysed thematically.

Discussion

This trial will provide evidence on the feasibility, safety, and acceptability of the MM and EEG-NF training in people with knee OA, thus informing the design of a full randomised clinical control trial.

[Neurofeedback in the treatment of cognitive impairment in patients with early cerebral small vessel disease]

OBJECTIVE

To compare the effectiveness of neurofeedback (NFB) at infra-low and alpha frequencies in the treatment of cognitive impairment in patients with early cerebral small vessel disease (cSVD).

MATERIAL AND METHODS

The study included 71 patients (average age 52.8±6.3 years, men 15%, women 85%) with early cSVD and 21 healthy volunteers (average age 53.2±4.8 years, men 29%, women 71%). All participants were assessed for clinical manifestations and cognitive functions, brain MRI, and EEG. cSVD patients were randomized by an envelope method with double-blind placebo control. Three groups of neurofeedback were formed: infra-low waves (n=25), alpha waves (n=22), simulated neurofeedback using EEG (placebo) (n=24). Fifteen sessions of 30 minutes were conducted 2-5 times a week. The cognitive profile and EEG were assessed immediately and 6-8 weeks after completion of the neurofeedback course.

RESULTS

Patients with early cSVD had subjective (65%) and moderate (35%) cognitive impairment with predominant deviations in the components of executive brain functions (EBF). Neurofeedback using infra-low waves significantly improved EBF in the components of productivity, switching and inhibition, non-verbal delayed memory immediately after the course, maintaining the effect for at least 6-8 weeks, which was accompanied by an increase in the power (μB2) of the alpha rhythm in the occipital regions. Neurofeedback using alpha waves showed improvement in the Stroop test (interference index) in the delayed period.

CONCLUSION

In patients with early cSVD and deterioration of EBF, it is preferable to conduct biofeedback neurotraining at infra-low frequencies to treat cognitive impairment and create a cognitive reserve. An increase in the power of the alpha rhythm in the occipital regions during the course can be considered a prognostic marker of its effectiveness.

Infra-Low-Frequency Neurofeedback Treatment in Dysthymia: A Case Study

Depression is one of the most common mental disorders worldwide. Dysthymia, a long-lasting form of depressive disorder that is also known as persistent depressive disorder (PDD) with pure dysthymic syndrome according to the Diagnostical and Statical Manual of Mental Disorders (DSM-5), is characterised by being difficult to treat. The most prominent therapeutic approaches in treating dysthymia are pharmacotherapy and psychotherapy, but recent studies also demonstrate the success of neurofeedback in treating individuals with depressive disorders. However, infra-low-frequency (ILF) neurofeedback, the main new neurofeedback protocol, lacks empirical evidence, and there is no evidence that it can treat dysthymia. This case report investigates the ILF neurofeedback method in a male patient with dysthymia. After 45 sessions of ILF neurofeedback combined with ILF synchrony, a decrease in symptom severity was found on assessment after treatment, and these results remained consistent at a low level at a 6-month follow-up. Additionally, the patient reported benefits on interpersonal and cognitive levels and in daily life situations. This study should incentivise further investigations into using ILF neurofeedback to treat dysthymia and all variations of depressive disorders.

Does combined training of biofeedback and neurofeedback affect smoking status, behavior, and longitudinal brain plasticity?

Introduction: Investigations of biofeedback (BF) and neurofeedback (NF) training for nicotine addiction have been long documented to lead to positive gains in smoking status, behavior and to changes in brain activity. We aimed to: (a) evaluate a multi-visit combined BF/NF intervention as an alternative smoking cessation approach, (b) validate training-induced feedback learning, and (c) document effects on resting-state functional connectivity networks (rsFCN); considering gender and degree of nicotine dependence in a longitudinal design. Methods: We analyzed clinical, behavioral, and electrophysiological data from 17 smokers who completed five BF and 20 NF sessions and three evaluation stages. Possible neuroplastic effects were explored comparing whole-brain rsFCN by phase-lag index (PLI) for different brain rhythms. PLI connections with significant change across time were investigated according to different resting-state networks (RSNs). Results: Improvements in smoking status were observed as exhaled carbon monoxide levels, Total Oxidative Stress, and Fageström scores decreased while Vitamin E levels increased across time. BF/NF promoted gains in anxiety, self-esteem, and several aspects of cognitive performance. BF learning in temperature enhancement was observed within sessions. NF learning in theta/alpha ratio increase was achieved across baselines and within sessions. PLI network connections significantly changed across time mainly between or within visual, default mode and frontoparietal networks in theta and alpha rhythms, while beta band RSNs mostly changed significantly after BF sessions. Discussion: Combined BF/NF training positively affects the clinical and behavioral status of smokers, displays benefit in smoking harm reduction, plays a neuroprotective role, leads to learning effects and to positive reorganization of RSNs across time. Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT02991781.

Neurofeedback in patients with frontal brain lesions: A randomized, controlled double-blind trial

Background

Frontal brain dysfunction is a major challenge in neurorehabilitation. Neurofeedback (NF), as an EEG-based brain training method, is currently applied in a wide spectrum of mental health conditions, including traumatic brain injury.

Objective

This study aimed to explore the capacity of Infra-Low Frequency Neurofeedback (ILF-NF) to promote the recovery of brain function in patients with frontal brain injury.

Materials and methods

Twenty patients hospitalized at a neurorehabilitation clinic in Switzerland with recently acquired, frontal and optionally other brain lesions were randomized to either receive NF or sham-NF. Cognitive improvement was assessed using the Frontal Assessment Battery (FAB) and the Test of Attentional Performance (TAP) tasks regarding intrinsic alertness, phasic alertness and impulse control.

Results

With respect to cognitive improvements, there was no significant difference between the two groups after 20 sessions of either NF or sham-NF. However, in a subgroup of patients with predominantly frontal brain lesions, the improvements measured by the FAB and intrinsic alertness were significantly higher in the NF-group.

Conclusion

This is the first double-blind controlled study using NF in recovery from brain injury, and thus also the first such study of ILF NF. Although the result of the subgroup has limited significance because of the small number of participants, it accentuates the trend seen in the whole group regarding the FAB and intrinsic alertness (p = 0.068, p = 0.079, respectively). We therefore conclude that NF could be a promising candidate promoting the recoveryfrom frontal brain lesions. Further studies with larger numbers of patients and less lesion heterogeneity are needed to verify the usefulness of NF in the neurorehabilitation of patients with frontal brain injury (NCT02957695 ClinicalTrials.gov).

Infra-Low Frequency Neurofeedback: A Systematic Mixed Studies Review

Introduction

Neurofeedback training is increasingly applied as a therapeutic tool in a variety of disorders, with growing scientific and clinical interest in the last two decades. Different Neurofeedback approaches have been developed over time, so it is now important to be able to distinguish between them and investigate the effectiveness and efficiency characteristics of each specific protocol. In this study we intend to examine the effects of Neurofeedback based on slow brain activity, the so-called Infra-Low Frequency (ILF) training a recently developed methodology that seems promising for the regulation of the central nervous system.

Aims

With this review we intend to summarize the currently existing literature on ILF-Neurofeedback, examine its quality and formulate indications about the clinical effectiveness of ILF-Neurofeedback.

Methods

Literature search was first conducted according to PRISMA principles, described, and then assessed using the MMAT appraisal tool. 18 well-documented studies of ILF-Neurofeedback training in human subjects were picked up and analyzed. Reports include group interventions as well as single case studies.

Results

Research data indicates good potential for ILF-Neurofeedback to influence brain activity and neurovegetative parameters. From the clinical profile, a salient common observation is a high level of individualization as a specific characteristic of ILF-Training: this feature seems to correlate with effectiveness of ILF-Neurofeedback, but also poses a challenge for researchers in terms of producing controlled and comparable findings; according to this point, some recommendation for future research on ILF-Neurofeedback are proposed. In conclusion, ILF-neurofeedback shows great potential for application for all those conditions in which the regulation of brain activity and neurophysiological processes are crucial. Further research will make it possible to complete the available data and to have a broader overview of its possible applications.

Effectivity of ILF Neurofeedback on Autism Spectrum Disorder-A Case Study

Autism spectrum disorder (ASD) is a neural and mental developmental disorder that impacts brain connectivity and information processing. Although application of the infra-low frequency (ILF) neurofeedback procedure has been shown to lead to significant changes in functional connectivity in multiple areas and neuronal networks of the brain, rather limited data are available in the literature for the efficacy of this technique in a therapeutic context to treat ASD. Here we present the case study of a 5-year-old boy with ASD, who received a treatment of 26 sessions of ILF neurofeedback over a 6-month period. A systematic and quantitative tracking of core ASD symptoms in several categories was used to document behavioral changes over time. The ILF neurofeedback intervention decreased the average symptom severity of every category to a remarkable degree, with the strongest effect (80 and 77% mean severity reduction) for physical and sleep symptoms and the lowest influence on behavioral symptoms (15% mean severity reduction). This case study is representative of clinical experience, and thus shows that ILF neurofeedback is a practical and effective therapeutic instrument to treat ASD in children.

Enhancing Brain Connectivity With Infra-Low Frequency Neurofeedback During Aging: A Pilot Study

Aging is associated with decreased functional connectivity in the main brain networks, which can underlie changes in cognitive and emotional processing. Neurofeedback is a promising non-pharmacological approach for the enhancement of brain connectivity. Previously, we showed that a single session of infra-low frequency neurofeedback results in increased connectivity between sensory processing networks in healthy young adults. In the current pilot study, we aimed to evaluate the possibility of enhancing brain connectivity during aging with the use of infra-low frequency neurofeedback. Nine females aged 52 ± 7 years with subclinical signs of emotional dysregulation, including anxiety, mild depression, and somatoform symptoms, underwent 15 sessions of training. A resting-state functional MRI scan was acquired before and after the training. A hypothesis-free intrinsic connectivity analysis showed increased connectivity in regions in the bilateral temporal fusiform cortex, right supplementary motor area, left amygdala, left temporal pole, and cerebellum. Next, a seed-to-voxel analysis for the revealed regions was performed using the post- vs. pre-neurofeedback contrast. Finally, to explore the whole network of neurofeedback-related connectivity changes, the regions revealed by the intrinsic connectivity and seed-to-voxel analyses were entered into a network-based statistical analysis. An extended network was revealed, including the temporal and occipital fusiform cortex, multiple areas from the visual cortex, the right posterior superior temporal sulcus, the amygdala, the temporal poles, the superior parietal lobule, and the supplementary motor cortex. Clinically, decreases in alexithymia, depression, and anxiety levels were observed. Thus, infra-low frequency neurofeedback appears to be a promising method for enhancing brain connectivity during aging, and subsequent sham-controlled studies utilizing larger samples are feasible.

Infra-Low Frequency Neurofeedback in Tension-Type Headache: A Cross-Over Sham-Controlled Study

Primary headaches are highly prevalent and represent a major cause of disability in young adults. Neurofeedback is increasingly used in the treatment of chronic pain; however, there are few studies investigating its efficacy in patients with headaches. We report the results of a cross-over sham-controlled study on the efficacy of neurofeedback in the prophylactic treatment of tension-type headache (TTH). Participants received ten sessions of infra-low frequency electroencephalographic neurofeedback and ten sessions of sham-neurofeedback, with the order of treatments being randomized. The study also included a basic psychotherapeutic intervention — a psychoeducational session performed before the main study phases and emotional support provided throughout the study period. The headache probability was modeled as a function of the neurofeedback and sham-neurofeedback sessions performed to date. As a result, we revealed a strong beneficial effect of neurofeedback and no influence of the sham sessions. The study supports the prophylactic use of infra-low frequency neurofeedback in patients with TTH. From a methodological point of view, we advocate for the explicit inclusion of psychotherapeutic components in neurofeedback study protocols.

Therapeutic Effect of Infra-Low-Frequency Neurofeedback Training on Children and Adolescents with ADHD

In this observational study the outcomes of an EEG-based infra-low-frequency (ILF) neurofeedback intervention on patients with attention deficit (hyperactivity) disorder (ADHD) are presented. The question is addressed whether this computer-aided treatment, which uses a brain-computer-interface to alleviate the clinical symptoms of mental disorders, is an effective non-pharmaceutical therapy for ADHD in childhood and adolescence. In a period of about 15 weeks 196 ADHD patients were treated with about 30 sessions of ILF neurofeedback in an ambulant setting. Besides regular evaluation of the severity of clinical symptoms, a continuous performance test (CPT) for parameters of attention and impulse control was conducted before and after the neurofeedback treatment. During and after the therapy, the patients did not only experience a substantial reduction in the severity of their ADHD-typical clinical symptoms, but also their performance in a continuous test procedure was significantly improved for all examined parameters of attention and impulse control, like response time, variability of reaction time, omission errors and commission errors. In a post neurofeedback intervention assessment 97% of patients reported improvement in symptoms of inattention, hyperactivity or impulsivity. Only 3% of the patients claimed no noticeable alleviation of ADHD-related symptoms. These results suggest that ILF neurofeedback is a clinically effective method that can be considered as a treatment option for ADHD and might help reducing or even avoiding psychotropic medication.

Training the Conductor of the Brainwave Symphony: In Search of a Common Mechanism of Action for All Methods of Neurofeedback

There are several different methods of neurofeedback, most of which presume an operant conditioning model whereby the subject learns to control their brain activity in particular regions of the brain and/or at particular brainwave frequencies based on reinforcement. One method, however, called infra-low frequency [ILF] neurofeedback cannot be explained through this paradigm, yet it has profound effects on brain function. Like a conductor of a symphony, recent evidence demonstrates that the primary ILF (typically between 0.01–0.1 Hz), which correlates with the fluctuation of oxygenated and deoxygenated blood in the brain, regulates all of the classic brainwave bands (i.e. alpha, theta, delta, beta, gamma). The success of ILF neurofeedback suggests that all forms of neurofeedback may work through a similar mechanism that does not fit the operant conditioning paradigm. This chapter focuses on the possible mechanisms of action for ILF neurofeedback, which may be generalized, based on current evidence.

Infra-Low Frequency Neurofeedback in the Treatment of Patients With Chronic Eating Disorder and Comorbid Post-Traumatic Stress Disorder

The treatment of patients suffering from an eating disorder and a comorbid post-traumatic stress disorder is challenging and often leads to poor outcomes. In a randomized control trial, we evaluated to what extent adding Infra-Low Frequency (ILF) neurofeedback could improve symptom reduction within an established inpatient treatment program. In a randomized two-group design, patients suffering from an eating disorder (anorexia nervosa, bulimia nervosa, or binge eating disorder) and comorbid post-traumatic stress disorder (N = 36) were examined while attending an inpatient treatment program in a clinic for psychosomatic disorders. The intervention group received ILF neurofeedback in addition to regular therapy, while the control group received “media-supported relaxation” as a placebo intervention. At the beginning and at the end of their treatment, all participants completed the Eating Disorder Examination-Questionnaire (EDE-Q) as a measure of eating disorder psychopathology and the Impact of Event Scale-Revised (IES-R) in order to assess symptoms of post-traumatic stress. Changes in EDE-Q and IES-R scores over time served as primary outcomes as well as an increase in body mass index in underweight patients. Secondary outcomes were the perceived benefit of the received intervention, global assessment of psychological treatment success, and complications in the course of treatment. Statistical evaluation was carried out with repeated measurement analysis of variance for the primary outcomes and with t-tests and Fisher’s exact test for the secondary outcomes. Our results indicate better treatment outcomes in the ILF neurofeedback group with regard to trauma-associated avoidance as well as with regard to restraint eating and increase in body weight. Furthermore, patients who had received ILF neurofeedback rated the intervention they received and, in tendency, their overall treatment more positively and they experienced fewer complications in the course of treatment. ILF neurofeedback is very well accepted by patients and seems to provide a relevant additional benefit in some aspects of symptom reduction. Findings confirm the feasibility of embedding this treatment approach in an inpatient setting and support the case for a larger study for greater statistical power.

Clinical Trial Registration: “Infra-Low Frequency Neurofeedback training in the treatment of patients with eating disorder and comorbid post-traumatic stress disorder”; German Clinical Trials Registry (https://www.drks.de; Identifier: DRKS00027826).