Z-Score Neurofeedback and Heart Rate Variability Training for Adults and Children with Symptoms of Attention-Deficit/Hyperactivity Disorder: A Retrospective Study

Heart Rate Variability Biofeedback Intervention Programme to Improve Attention in Primary Schools

The importance of attentional capacity for academic performance is highlighted by the increasing demands placed on students during primary school. Between the ages of 7 and 12, there is an evolutionary improvement in attentional capacity and the school environment is considered an appropriate setting in which to develop programmes to improve attention. Heart rate variability is an appropriate indicator of attentional capacity. For all these reasons, a heart rate variability biofeedback intervention focused on breathing was developed and implemented to improve attention. The intervention consisted of two phases. In the first phase, the school teachers were trained to develop the intervention; in the second, students received five individual sessions from their teachers. In each individual session, they learned to breathe to increase their heart rate variability. A total of 272 girls and 314 boys (N = 586) aged 7-12 years participated in the programme. To study the impact of the intervention on three primary school age groups, the attention of Control and Experimental groups was assessed before and after the implementation of the programme. According to the data obtained, despite developmental improvements, the students who participated in the programme showed an increase in heart rate variability and an improvement in attentional capacity, with a greater impact on the first cycle of primary school. The usefulness of heart rate variability biofeedback interventions in improving attention in primary school is discussed and arguments for their use in children are presented.

A systematic review of the utility of continuous performance tests among adults with ADHD

OBJECTIVE

The clinical utility of continuous performance tests (CPTs) among adults with attention-deficit/hyperactivity disorder (ADHD) has increasingly been brought under question. Therefore, the objective of this study was to systematically review the literature to investigate the clinical utility of various commercially available CPTs, including the Conner's Continuous Performance Test (CCPT), Test of Variables of Attention (TOVA), Gordon Diagnostic System (GDS), and Integrated Visual and Auditory Continuous Performance Test (IVA) in the adult ADHD population.

METHODS

This systematic review followed the a priori PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Articles were gathered from PsycINFO, PsycARTICLES, Academic Search Complete, and Google Scholar on 11 April 2022. Sixty-nine articles were included in the final review. Risk of bias was assessed using the National Institute of Health Quality Assessment Took for Observational Cohort and Cross-Sectional Studies.

RESULTS

Most articles demonstrated high risk of bias, and there was substantial heterogeneity across studies. Overall, the reviewed CPTs appeared to have limited diagnostic utility and classification accuracy. Although many studies showed differing scores between adults with ADHD and comparison groups, findings were not consistent. Characteristics of CPT performances among adults with ADHD were mixed, with little consistency and no evidence of a clear profile of performances; however, CCPT commission errors appeared to have the most utility when used a treatment or experimental outcome measure, compared to other CCPT scores.

CONCLUSION

Overall, CPTs should not be used in isolation as a diagnostic test but may be beneficial when used as a component of a comprehensive assessment.

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.

A review of recent treatments for adults living with attention-deficit/hyperactivity disorder

Background

Attention-deficit/hyperactivity disorder (ADHD) is a neuro-developmental disorder prevalent among children and adults. Adults living with ADHD can experience significant distress affecting their daily functioning on emotional, physical, interpersonal, familial and financial levels. Intervention programmes may be a way to mitigate these challenges.

Aim

This review identified good evidence-based intervention studies for adults with ADHD and described the usefulness of these interventions.

Method

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, articles were searched from 2009 to 2019 across four medical- and psychological-focused electronic databases using EBSCOhost. All articles selected for the review's thematic meta-synthesis were appraised by attaining a threshold score of at least 61%, using the Smith-Franciscus-Swartbooi appraisal tool. Two autonomous reviewers engaged in the review process. The study adhered to all ethical principles pertaining to systematic review practice.

Results

Forty studies were identified for summation, including pharmacological, non-pharmacological and neuro-stimulation approaches. Most interventions used a multimodal approach. Results indicated the most effective stimulant and non-stimulant as methylphenidate and atomoxetine, respectively. Effective non-pharmacological approaches to treatment were identified as cognitive-behavioural treatment, mindfulness-based approaches, psycho-education and dialectical-focused therapies. Bright light treatment and neurofeedback were reported as the most efficacious neuro-stimulatory methods.

Conclusion

Pharmacological and non-pharmacological approaches, as well as neuro-stimulation or a blend of these approaches were acknowledged as the most effective recent modalities in the treatment of adult ADHD.

Contribution

This review reported on the most current approaches to treat adult ADHD. This will facilitate a better understanding and informed decisions with regard to dealing with adult ADHD.

Technologies to support the diagnosis and/or treatment of neurodevelopmental disorders: A systematic review

In recent years, there has been a great interest in utilizing technology in mental health research. The rapid technological development has encouraged researchers to apply technology as a part of a diagnostic process or treatment of Neurodevelopmental Disorders (NDDs). With the large number of studies being published comes an urgent need to inform clinicians and researchers about the latest advances in this field. Here, we methodically explore and summarize findings from studies published between August 2019 and February 2022. A search strategy led to the identification of 4108 records from PubMed and APA PsycInfo databases. 221 quantitative studies were included, covering a wide range of technologies used for diagnosis and/or treatment of NDDs, with the biggest focus on Autism Spectrum Disorder (ASD). The most popular technologies included machine learning, functional magnetic resonance imaging, electroencephalogram, magnetic resonance imaging, and neurofeedback. The results of the review indicate that technology-based diagnosis and intervention for NDD population is promising. However, given a high risk of bias of many studies, more high-quality research is needed.

Evaluation of Sympathetic and Parasympathetic Tone and Reactivity in Adolescents with Specific Learning Disorder (Dyslexia)

OBJECTIVES

To evaluate the autonomic function in specific learning disorder (SLD) and comorbid SLD attention-deficit hyperactivity disorder (SLD-ADHD).

METHODS

A cross-sectional study was conducted in a tertiary care hospital with 20 adolescent subjects each of confirmed SLD, SLD-ADHD, and healthy control (mean age 15.32 y). Heart-rate variability and autonomic-function tests were carried out using standard protocols.

RESULTS

Heart-rate variability parameters, viz., mean RR interval, number of RR intervals which differ by ≥ 50 ms (NN50), percentage NN50, standard deviation of differences between adjacent RR intervals, root square of mean of the sum of the squares of differences between adjacent RR intervals, coefficient of variance and absolute power of high-frequency band (HF) recorded apparently lower levels in SLD and SLD-ADHD as compared to healthy control indicating lower parasympathetic tone. Whereas, higher absolute power of low- frequency band (LF) in SLD and SLD-ADHD than healthy control indicated enhanced sympathetic activity. Higher LF/HF and lower SD1/SD2 ratios in SLD and SLD-ADHD than healthy control indicated higher sympathetic tone over parasympathetic tone. Values of autonomic-function tests such as E:I ratio, change in heart rate during deep-breathing test, 30:15 ratio, and Valsalva ratio showed a decrease in SLD and SLD-ADHD as compared to healthy control implying reduction in parasympathetic reactivity. Increased values for rise in diastolic blood pressure in the isometric handgrip test and cold pressor test recorded in SLD as compared to healthy control, revealed the increased sympathetic reactivity.

CONCLUSION

Overall, results of heart-rate variability and autonomic-function tests imply dysregulation of sympathetic and parasympathetic activities with sympathetic dominance in SLD and SLD-ADHD.

Is heart rate variability biofeedback useful in children and adolescents? A systematic review

BACKGROUND

Heart rate variability (HRV) is considered as an index of both physical and emotional health, and biofeedback aiming to increase the level of HRV has demonstrated extensive beneficial effects. Although HRV biofeedback is commonly and reliably applied in adults, the use of this technique, alone or in addition to other treatments, in children and adolescents has not been widely explored to date.

METHODS

This systematic review following PRISMA guidelines covers all human studies using HRV biofeedback in children and adolescents. A literature search was conducted in PsycINFO, PubMed and Scopus, and a standardized methodological quality assessment was performed.

RESULTS

Results showed the efficiency of HRV biofeedback sessions with children and adolescents to reduce physical and mental health-related symptoms and enhance well-being.

CONCLUSIONS

These findings underline the therapeutic value of using HRV biofeedback as a complement to more conventional behavioural and cognitive interventions to help children to manage stress and/or pain. Capitalizing on the identified strengths and shortcomings of available results, we propose research avenues as well as evidence-based clinical guidelines for using HRV biofeedback in clinical paediatric settings.

Slow Cortical Potential Versus Live Z-score Neurofeedback in Children and Adolescents with ADHD: A Multi-arm Pragmatic Randomized Controlled Trial with Active and Passive Comparators

Neurofeedback (NF) as a treatment for Attention Deficit Hyperactivity Disorder (ADHD) has been evaluated in several trials, but the specificity and generalizability of effects remain unclear. This four-arm randomized controlled trial evaluated the efficacy of Slow Cortical Potential (SCP; standard NF protocol) and Live Z-score (LZS; non-standard NF protocol) delivered in high-frequency format (five sessions per week during five weeks), compared to Working-memory training (WMT; active comparator) and Treatment-as-usual (TAU; passive comparator). N = 202 children/adolescents aged 9 to 17 years with ADHD participated. The primary outcome measure was multi-report (self-, teacher-, and parent-report) ADHD core symptoms on the Conners-3, assessed at baseline, posttreatment, and 6-months follow-up. Data were analyzed using a linear mixed model. Between-group differences were scarce and did not show a distinct pattern. Superiority of LZS over TAU at endpoint were observed for teacher-rated measures only, while significant differences between SCP and TAU were restricted to posttreatment measurements. Contrary to our expectations, LZS outperformed SCP at endpoint for teacher-rated hyperactivity (-5.37; 95% CI: -10.14 to -0.60; p = .028; d = -.36) and overall ADHD symptoms (-2.20; -4.18 to -0.22; p = .030; d = -.41). There was no indication that either form of NF was superior to WMT. No severe adverse events were reported during the trial, whereas transient stress-related problems were quite frequent. Overall, the results from this pragmatic trial do not provide convincing support for broad implementation of NF in child and adolescent psychiatric services. Future research should try to clarify for whom and under what circumstances NF might be a viable treatment option.

Does Heart Rate Variability Biofeedback Enhance Executive Functions Across the Lifespan? A Systematic Review

The scope of this systematic review was to summarize the existing literature on the effects of heart rate variability biofeedback (HRV-BF) on executive functions (EFs) across the lifespan. Specifically, it aimed to investigate the factors that may affect the efficacy of HRV-BF interventions, such as the study population, duration and intensity of the intervention, or the technical equipment. This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies that measured and presented at least one EF were included. We included controlled and uncontrolled trials involving clinical and general populations. From the initial list of 137 papers, 16 final studies were reviewed, with 777 participants. Fifty-six percent of the studies included in this review reported significant positive effects of HRV-BF intervention on at least one EF. Attention was the domain that most often benefited from the intervention. The majority of EF improvements (78%) occurred in studies that addressed patient populations or individuals that may present particular profiles: individuals exposed to stress, professional athletes, war veterans, children and adults with ADHD, and clinical older patients. The remaining studies (22%) that reported significant improvements focused on the general population. Efficacy was neither related to the duration or intensity of the intervention nor related to the technical equipment. Overall, our review shows that HRV-BF may be beneficial (a) to increase attentional skills, inhibition, and working memory and (b) when targeting more vulnerable individuals or individuals with particular profiles. However, further development of standardized, controlled protocols and consistent reporting of effect sizes may contribute to establishing the relevance of HRV-BF biofeedback interventions within the field of cognitive enhancement.

Individual Alpha Peak Frequency, an Important Biomarker for Live Z-Score Training Neurofeedback in Adolescents with Learning Disabilities

Learning disabilities (LDs) have an estimated prevalence between 5% and 9% in the pediatric population and are associated with difficulties in reading, arithmetic, and writing. Previous electroencephalography (EEG) research has reported a lag in alpha-band development in specific LD phenotypes, which seems to offer a possible explanation for differences in EEG maturation. In this study, 40 adolescents aged 10–15 years with LDs underwent 10 sessions of Live Z-Score Training Neurofeedback (LZT-NF) Training to improve their cognition and behavior. Based on the individual alpha peak frequency (i-APF) values from the spectrogram, a group with normal i-APF (ni-APF) and a group with low i-APF (li-APF) were compared in a pre-and-post-LZT-NF intervention. There were no statistical differences in age, gender, or the distribution of LDs between the groups. The li-APF group showed a higher theta absolute power in P4 (p = 0.016) at baseline and higher Hi-Beta absolute power in F3 (p = 0.007) post-treatment compared with the ni-APF group. In both groups, extreme waves (absolute Z-score of ≥1.5) were more likely to move toward the normative values, with better results in the ni-APF group. Conversely, the waves within the normal range at baseline were more likely to move out of the range after treatment in the li-APF group. Our results provide evidence of a viable biomarker for identifying optimal responders for the LZT-NF technique based on the i-APF metric reflecting the patient’s neurophysiological individuality.

Z-score neurofeedback, heart rate variability biofeedback, and brain coaching for older adults with memory concerns

BACKGROUND

The three-month, multi-domain Memory Boot Camp program incorporates z-score neurofeedback (NFB), heart rate variability (HRV) biofeedback, and one-on-one coaching to teach memory skills and encourage behavior change in diet, sleep, physical fitness, and stress reduction.

OBJECTIVE

This prospective trial evaluates the Memory Boot Camp program for adults ages 55 to 85 with symptoms of Mild Cognitive Impairment (MCI) and subjective memory complaints.

METHODS

Participants were evaluated via the Montreal Cognitive Assessment (MoCA), NeuroTrax Global Cognitive Score, measures of anxiety, depression, sleep, quality of life, quantitative electroencephalography (QEEG), and HRV parameters at four timepoints: baseline, pre-program, post-program, and follow-up. The trial included a three-month waiting period between baseline and pre-program, such that each participant acted as their own control, and follow-up took place six months after completion of the program.

RESULTS

Participants' MoCA scores and self-reported measures of anxiety, depression, sleep quality, and quality of life improved after treatment, and these changes were maintained at follow-up. Physiological changes in HRV parameters after treatment were not significant, however, breathing rate and QEEG parameters were improved at post-program and maintained at follow-up. Finally, participants' improvement in MoCA score over the treatment period was correlated with their improvement in two brain oscillation parameters targeted by the z-score NFB protocol: relative power of delta and relative power of theta.

CONCLUSIONS

Trial results suggest that the Memory Boot Camp program is a promising treatment strategy for older adults with symptoms of MCI and subjective memory complaints.

Updates in technology-based interventions for attention deficit hyperactivity disorder

PURPOSE OF REVIEW

Technological advancement has led to the development of novel treatment approaches for attention deficit hyperactivity disorder (ADHD). This review aims to review recent studies which employ the use of technology to treat ADHD, with particular focus on studies published during a 1-year period from February 2019 to February 2020.

RECENT FINDINGS

Most recent studies involved children aged 12 years and below. Interventions included cognitive training through games, neurofeedback and a combination of several approaches. More novel approaches included trigeminal nerve stimulation and brain-computer interface, and studies had utilized technology such as X-box Kinect and eye tracker. There was a shift towards delivering intervention at home and in school, enabled by technology. The study outcomes were variable and mainly included executive functioning measures and clinical ratings. These interventions were generally safe with few reported adverse events.

SUMMARY

Technology has enabled interventions to be delivered outside of the clinic setting and presented an opportunity for increased access to care and early intervention. Better quality studies are needed to inform on the efficacy of these interventions.