Infralow Frequencies Research Articles

The Impact of Neurofeedback Training on Cognitive Abilities Assessed by the Wechsler Intelligence Scale for Children-Revised in Children with Attention Deficit: A Randomized Single-Blind Sham-Controlled Study.

This study aims to investigate the effects of a neurofeedback system on cognitive skills, as measured by the Wechsler Intelligence Scale for Children-Revised (WISC-R), in a cohort of 100 children aged 8 to 12 who were diagnosed with attention deficit. A randomized single-blind sham control group design was employed, with 50 participants assigned to the experimental group receiving neurofeedback training and 50 participants assigned to the sham group receiving simulated training. Participants were selected through random sampling from individuals seeking assistance at a specialized education center over the course of one year (May 2021-2022). Pre- and post-test WISC-R assessments were administered to both groups to evaluate participants' mental performance. The experimental group underwent a total of 60 sessions of quantitative electroencephalography-based infralow frequency neurofeedback training, with half-hour sessions conducted three days a week over a five-month period. The post-test WISC-R was administered at the end of the sixth month. The results revealed significant differences between the pre- and post-training test scores, specifically in terms of verbal IQ, picture arrangement, performance IQ, and total IQ (p = 0.016, p = 0.001, p < 0.001, and p = 0.002, respectively), when comparing the differences between the two groups. These findings indicate a notable improvement in performance IQ, total IQ, and a reduction in attention deficits among the neurofeedback group based on the WISC-R assessments. Future studies should consider employing larger sample sizes, including appropriate control groups, and conducting long-term follow-ups to further elucidate the clinical significance of these results.

Effect of Infra Low Frequency (ILF) neurofeedback training on EEG in children with autism spectrum disorders.

To investigate whether Infra-low frequency Neurofeedback (ILF-NFB) training can improve brain electrical activity in children with autism spectrum disorders ASD. This single arm pre and post intervention study was carried out at IBMS (Institute of Basic Medical Sciences), Khyber Medical University, Peshawar and Shaheed Zulfiqar Ali Bhutto Medical University (SZABMU), Islamabad from January 2021 to December 2022. A purposive sampling technique was used. Thirty-five ASD children (male=24; female=11; 7-17 years) were provided with 30 sessions of infra low frequency (ILF) neurofeedback training for 15-20 minutes, during 10 weeks. Childhood Autism Rating Scale (CARS) scoring was done and electroencephalogram (EEG) activity was compared before and after ILF-NF training sessions. Around 62.9% participants had mild-moderate autism and 37.1% had severe autism. Wilcoxon Signed rank test revealed a significant decline in delta (Pre-test=47.31±19.22, Post-test=22.07±6.83; p=<0.001), theta (Pre-test=24.75±16.62, Post-test=12.37±3.59; p=<0.001) and alpha (Pre-test=12.01±9.81, Post-test=4.03±1.61; p=< 0.001) waves. Mann Whitney U test exhibited no significant gender differences in EEG pattern before and after neurofeedback except in theta waves (p=0.03) before the intervention. Decline in delta, theta, beta and alpha waves propose that ILF-NF training can be effective in improving the EEG activity. ILF-NFB can be perceived as a valuable non-invasive, non-pharmacological intervention for improving EEG pattern via reintegration of brain activity resulting in increased the attention and focus, enhanced mental stability and cognitive engagement.

ОСОБЛИВОСТІ ПОБУДОВИ ІМПЕДАНСОМЕТРИЧНИХ КАНАЛІВ ДЛЯ РОБОТИ НА НИЗЬКИХ ТА ІНФРАНИЗЬКИХ ЧАСТОТАХ

The features of the low and infra-low frequency ranges of harmonic measurement signals, as well as the properties of the investigated objects, which must be taken into account during the construction of impedance measuring channels, are determined. To combine the necessary metrological characteristics of such channels (accuracy, speed, immunity), an approach is used, consisting in analog-to-digital conversion of signals received from sensors, and subsequent application of digital methods of their processing. Options for implementing this approach using digital methods for determining the amplitude of sinusoidal signals were considered and analyzed, among which the most promising ones were selected for metrological support of impedance measurements at low and infra-low frequencies. The perspective of using parallel-serial analog-digital conversion of an informative signal with its continuous integration at these frequencies is shown. Conclusions were made and recommendations were given regarding the use of the considered methods taking into account the properties of the measurement objects. References 16.

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.

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

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). 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. 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. 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.

The impact of ILF neurofeedback on inhibitory control in high-functioning adolescents with autism spectrum disorder: Preliminary evidence of a randomized controlled trial

Background Individuals with Autism Spectrum Disorder (ASD) often exhibit impairments in inhibitory control, which can impact their cognitive functioning. This study aimed to investigate the effectiveness of Infra-Low Frequency (ILF) neurofeedback in improving inhibitory control among high-functioning adolescents with ASD. Methods A single-blind, two-armed randomized controlled trial was conducted with 24 adolescents with ASD randomly divided into two groups (active and sham; n = 12 per group). Both groups participated in 15 sessions of one-hour ILF neurofeedback, three times per week. The ILF neurofeedback protocol was applied to the active group, while the sham group received an inactive intervention. Outcomes were measured at the pretest, post-test, and follow-up stages. Results ILF neurofeedback significantly improved inhibitory control in adolescents with ASD, as indicated by improvements in behavioral measures and absolute power analysis. The most significant differences were observed in alpha, theta, and gamma waves located in the central areas of the left gyrus. However, no significant effect was observed at the follow-up level on either behavioral measures or absolute power. Conclusion The results suggest that ILF neurofeedback is effective in improving inhibitory control in high-functioning adolescents with ASD. This non-invasive intervention has the potential to improve inhibitory control in this population. However, future research is needed to determine the long-term effects of ILF neurofeedback.

Mechanisms of Current Transition in High Compensated Silicon Samples with Zinc Nanoclusters

This article presents experimental results on the study of the current-voltage characteristics of strongly compensated n- and p-type silicon samples diffusion-doped with zinc at a temperature of 80 K. The current-voltage characteristics of the studied samples contain both sublinear and superlinear sections. Several (up to eight) characteristic areas were found, the number of which depends on the degree of illumination, temperature, and electrical resistivity of the sample. Under certain conditions, there is an alternation of sections of the current-voltage characteristic with negative differential conductivity of the N- and S-type, behind which current instabilities with an infra-low frequency are observed. The appearance of sections of the current-voltage characteristic with a quadratic dependence is explained by the presence of fast and slow recombination centers associated with zinc nanoclusters, and sublinear sections are explained in terms of the theory of the "injection depletion effect". The formation of nanoclusters with the participation of zinc ions was confirmed by atomic force microscopy studies.

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.

The Changes of the Infra-Slow EEG Fluctuations of the Brain Potentials under Influence of Infra-Low Frequency Neurofeedback

This study presents a comparison of the effect on EEG electrical activity in the range of infraslow frequencies of two methods: infra-low frequency EEG biofeedback and heart rate variability training. The study involved 17 healthy subjects aged 21 to 50 years with minor symptoms of a physiological or psychological nature, who did not have a history of neurological or psychiatric diseases. To evaluate the results of the training, we analyzed the spectral power of slow EEG oscillations during the performance of the attention test (Visual Go/NoGo), recorded before and after twenty sessions of biofeedback. Both the subjective assessment of the physiological and psychological state and the results of the visual test showed more pronounced positive changes under the influence of EEG biofeedback compared to the cases of heart rate variability training. A significant increase in the amplitudes of oscillations in the infraslow EEG range was observed only after EEG biofeedback.

Frequency Response of a Ferroelectric Composite Synthesized from Cellulose Nanoparticles and Rochelle Salt

The study provides frequency spectra of several electrophysical parameters of dielectric permittivity, dielectric loss tangent, conductivity, electrical impedance and electric modulus to explore the frequency response at low and infralow frequencies (10−2–106 Hz) for the ferroelectric composite synthesized from cellulose nanoparticles and Rochelle salt. The experimental results confirmed the main contribution of conductivity into the frequency response with the presence of two relaxation processes. The first one was related to the intrinsic relaxation inside the composite while the second one was caused by the influence of electrode effects. Besides, the significant dispersion of dielectric permittivity obeying Maxwell-Wagner-Sillars mechanism has also been detected.

Infra-low frequency neurofeedback and insomnia as a model of CNS dysregulation.

This paper will review what is conventionally known of sleep homeostasis and focus on insomnia as a primary manifestation of brain dysregulation, whether as a solitary symptom or as part of a larger syndrome such as post-traumatic stress disorder, PTSD. It will discuss in brief behavioral/mindfulness treatments that have been used to treat neurologic diseases, as this is germane to the phenomenology of neurofeedback (NF). It will explore how neurofeedback may work at the subconscious level and cover the current clinical experience of the effectiveness of this technique in the treatment of insomnia. It will conclude with a case presentation.

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

BackgroundFrontal 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.ObjectiveThis 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 methodsTwenty 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.ResultsWith 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.ConclusionThis 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).

МІНІМІЗАЦІЯ ВИПАДКОВОЇ ПОХИБКИ ЦИФРОВОГО МЕТОДУ ВИМІРЮВАННЯ АМПЛІТУДИ СИНУСОЇДАЛЬНОГО СИГНАЛУ

The errors of measuring the amplitude of sinusoidal signals by the method based on calculating the sum of the ratios of digital samples of instantaneous signal values to the sines of the phase angles corresponding to the sampling moments are investigated. A mathematical expression for determining the total random measurement error using the values of the parameters of the error components is obtained. It is shown that there is a minimum value of the total random measurement error as a function of the number of instantaneous signal values taken into account. The method of reducing the level of random error to the desired level is given. The method can be used to create metrological support for measuring the parameters of electrical signals at low and infralow frequencies, including industrial frequency. Ref. 7, fig. 4, table.

Infra-low frequency neurofeedback in application to Tourette syndrome and other tic disorders: A clinical case series.

We describe our clinical experience in treating patients with Tourette syndrome and other tic disorders using infra-low frequency neurofeedback (ILF NF), often in conjunction with cognitive behavior therapy. Following a narrative description of our approach, we present outcome data for 100 successive cases. Many of the children and adolescents that we have treated since 2005 did not derive sufficient benefit from standard treatment for Tourette syndrome and other tic disorders. In our clinical experience, based on extensive before- and after- testing and symptom tracking, this patient group derived significant additive benefit from complementary neurofeedback treatment. The majority of trainees attained a higher level of functioning and were able to live up to their potential in a way they were not able to prior to neurofeedback treatment.

Managing Intractable Symptoms of Parkinson's Disease: A Nonsurgical Approach Employing Infralow Frequency Neuromodulation.

Managing Intractable Symptoms of Parkinson's Disease: A Nonsurgical Approach Employing Infralow Frequency Neuromodulation.

Elastic and dielectric responses of VDF70/Tr30 near ferroelectric phase transition

The infra-low frequency elastic modulus and the complex dielectric permittivity of vinylidene fluoride trifluoroethylene VDF70/Tr30, are studied within the temperature range of 20 ÷ 140 °C. The experimental results are used to determine the temperature dependence of order parameter η near the Curie temperature (T c). It is revealed that spontaneous polarization P s and spontaneous strain xs are linearly coupled. The dielectric dispersion, due to the relaxation dynamics of polar microregions in the vicinity of the T c, is found. The average relaxation time follows the Arrhenius law with activation energy depending on temperature.

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.

Documenting the Impact of Infra Low Frequency Neurofeedback on Underserved Populations With Complex Clinical Presentations.

There is a crisis in mental health. The demand for services is huge; the efficacy of current services is lacking, and the traditional path to developing effective treatments is not working. This paper describes an approach based on implementing infra low frequency (ILF) neurofeedback in agencies that work with the underserved and collecting data on client’s concerns, behavior, quality of life and cognitive performance. We also track session-by-session changes in client concerns and their relation to ILF neurofeedback protocols. Results are reviewed for over 300 clients who have been seen in such agencies. Limitations and future directions are discussed for this model.

Use of Novel Concussion Protocol With Infralow Frequency Neuromodulation Demonstrates Significant Treatment Response in Patients With Persistent Postconcussion Symptoms, a Retrospective Study.

IntroductionConcussion is a growing public health concern. No uniformly established therapy exists; neurofeedback studies report treatment value. We use infralow frequency neuromodulation (ILF) to remediate disabling neurological symptoms caused by traumatic brain injury (TBI) and noted improved outcomes with a novel concussion protocol. Postconcussion symptoms (PCS) and persistent postconcussion symptoms (PPCS; >3 months post head injury) are designated timelines for protracted neurological complaints following TBI. We performed a retrospective study to explore effectiveness of ILF in PCS/PPCS and investigated the value of using this concussion protocol.MethodPatients with PCS/PPCS seen for their first neurology office visit or received their first neurofeedback session between 1 August 2018 and 31 January 2021 were entered. Outcomes were compared following treatment as usual (TAU) vs. TAU with ILF neurotherapy (TAU+ILF). The study cohort was limited to PPCS patients; the TAU+ILF group was restricted further to PPCS patients receiving at least 10 neurotherapy sessions. Within the TAU+ILF group, comparisons were made between those who trained at least 10 sessions using concussion protocol (TAU+ILF+CP) and those who trained for at least 10 sessions of ILF regardless of protocol (TAU+ILF-CP).ResultsAmong our resultant PPCS cohort (n = 59) leading persistent neurological complaints were headache (67.8%), memory impairment (57.6%), and brain fog (50.8%). PPCS patients in TAU+ILF+CP (n = 25) demonstrated greater net (p = 0.004) and percent (p = 0.026) improvement of symptoms compared to PPCS subjects in TAU (n = 26). PPCS patients in TAU+ILF-CP (n = 8) trended toward significant symptom improvements compared to TAU, and TAU+ILF+CP trended toward greater efficacy than TAU+ILF-CP.ConclusionPPCS patients who received TAU+ILF+CP demonstrated significantly greater improvement as a group when compared to TAU. When used as an integrative modality to treatment as usual in managing patients with PPCS, ILF neuromodulation with use of concussion protocol provided significant symptom improvements.

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.