This systematic review looked at 587 journal articles that reported using neurofeedback as a treatment for autism. From these studies, ninety-four percent of nonrandomized controlled and experimental trials observed positive results and long-term positive effects.

Autism spectrum disorder is characterized by abnormal function in core social brain regions. In this repeated-measured design clinical trial, 15 autism spectrum disorder patients were enrolled in a 5-session training program of real-time functional magnetic resonance imaging neurofeedback targeting facial emotion expressions processions, using the posterior superior temporal sulcus as region-of-interest. Participants modulated the activity in this region-of-interest over multiple sessions. Participants were able to control their own brain activity in this social brain region, with positive clinical and neural effects. 

Neurofeedback (NFB) is a means through which participants can have voluntary control on their brain waves being expressed on the EEG. Forty-two autistic children received a NFB therapy aiming at improving their cognitive abilities. Neurofeedback succeeded in decreasing children’s high theta/beta ratio by inhibiting theta activity and intensifying beta activity over different sessions. Following therapy, the children’s cognitive functions were found to show comparative improvement compared to pre-treatment assessment on a range of different tasks. Auxiliary improvements were found in their social, thought and attention domains.

In this article, a neurofeedback protocol using slow cortical potentials (SCPs) was utilized on 41 male adolescents with ASD to determine if neurofeedback could reduce core symptomatology of ASD. The experimental group underwent 24 EEG -based training sessions, while the active control group underwent a conventional treatment - clinical counselling. Core autistic symptomatology was measured at six different time points during the interventions. Konicar et al. found improvements in core ASD symptomatology in the experimental group while only seeing slight improvement in the control group. As well, continuous decreases in delta power along with increases in alpha power were also found. These analyses suggest that SCP neurofeedback has a positive impact on individuals with ASD and that behavioural and neural changes related to neurofeedback training are complex and non-linear.

Brezis et al. hypothesized that the intervention of biofeedback would decrease participants’ anxiety and autism symptoms, and increase their self-awareness, self-determination, and empathy. Fourteen adults with ASD, residing in assisted living, were provided with 16 weekly half-hour contemplative-biofeedback sessions with non-professional trainers, in which they learned to reduce their arousal levels through combined biofeedback and contemplative techniques, and apply those to everyday life. Data was collected both pre- and post- intervention, to determine changes in participants’ self awareness, self-determination, anxiety, autism symptoms, and empathy. Participants were capable of successfully improving their physiological arousal levels on the biofeedback setup, indicating feasibility of the technique. Further, initial indications for reduction in autism symptoms and increased self-determination were found. Qualitative reports found participants applied the techniques in many real-life situations, and these had far-ranging effects on their emotional regulation, work and social motivation, and self-determination.

Postural control is a fundamental part of human development as it allows us to stand, walk, play, and interact with our environment. Some individuals with autism spectrum disorder (ASD) have difficulties with postural stability. This study wanted to observe the effects of visual-based biofeedback training on improving balance challenges in those with ASD. Twenty-nine youth between the ages of 7 to 17 with ASD completed a 6-week biofeedback-based videogame for balance training. The authors aimed to (1) report session-by-session balance changes, (2) determine whether balance-training changes would be seen outside of the game, (3) the characteristics of participants who benefited the most from training, and (4) record the subjective training experience of the participants and their families. Participants showcased training-related balance improvements with postural-sway improvements seen outside of typical training. Participants with less severe repetitive behaviours and better starting balance appeared to have benefited the most out of biofeedback-based balance training. These results demonstrate the association between neurofeedback and balance improvements in youths with ASD.

Autism has been characterized by atypical task-related brain activation and functional connections, coinciding with socio-communicative abilities. However, evidence of the brain’s experience-dependent plasticity suggests that abnormal activity patterns may be reversed with treatment. Datko et al. (2018) examined the effects of ≥20h of sensorimotor mu-rhythm-based neurofeedback training (NFT) in children with high-functioning autism spectrum disorders (ASD) and a matched control group of typically developing children (ages 8-17). During a functional magnetic resonance imaging imitation and observation task, the ASD group showed increased activation in regions of the human mirror neuron system following the Neurofeedback training, as part of a significant interaction between group (ASD vs. controls) and training (pre- vs. post-training). These changes were positively correlated with behavioural improvements in the ASD participants, indicating that mu-rhythm Neurofeedback may be beneficial to individuals with ASD.

In this paper Kouijzer et al. (2009) study the long-term results of neurofeedback treatment in the same group of children with ASD after 12 months. The study indicated the maintenance of improvement of executive functions and social behaviour after 12 months in comparison with the immediate outcomes. 

Impaired facial processing may be a contributing factor to social dysfunction in certain individuals with autism spectrum disorder (ASD). Previous studies show potential in using an EEG-based and fMRI-based neurofeedback therapy to help individuals with ASD learn to regulate regional brain activity thus reducing symptoms of impaired facial processing. This study wanted to investigate the effectiveness of functional near-infrared spectroscopy (fNIRS)- based neurofeedback training in children with ASD. Four subjects participated in this study; two participants with ASD and two that were typically developing (TD). One ASD and TD participant underwent five sessions of fNIRS based neurofeedback training and the other ASD and TD participant received sham-feedback therapy. All participants engaged in a facial-identity training program where they received implicit reinforcement based on their brain activity and behavioral performance. Results of the study showed that after five sessions, both the ASD and TD participant that received fNIRS-NFB therapy showed more improvement in facial recognition performance compared to the participants receiving sham-feedback. This improvement was even more prominent in the participant with ASD. Overall, fNIRS-based neurofeedback could help to enhance therapeutic intervention in children with ASD.

Autism Spectrum Disorder (ASD) is a group of neurodevelopmental disorders with  impairments in social communication and repetitive/restrictive behaviors.  The purpose of this semi-experimental study is to investigate the effectiveness of Neurofeedback therapy in regulating neuro and metabolic functions in the brain that contribute to these ASD symptoms. 26 children with ASD performed 40 sessions of Neurofeedback therapy and their brain wave activity was recorded before and after the intervention using EEG/ERP 19 channels. The results of the study showed that the average Theta (low frequency) power decreased and there was no difference in the Gamma power (high frequency.) Overall, their findings show that Neurofeedback training has the potential to improve Theta brain wave activity which can in turn lead to better social communication in children with ASD.

Some characteristics of autism include deficits in communication, social interaction and a limited range of interests with repetitive actions. Various abnormalities in the brains of individuals with autism have been documented. Patterns of hyper- and hypo- connectivity have been identified with the use of QEEG which may be malleable to the effects of neurofeedback. In this study, the researchers compared the results of two previously published controlled studies that examined the effectiveness of neurofeedback in the treatment of autism. They looked at whether a symptom based approach or a connectivity guided based approach was more effective. They found that connectivity guided neurofeedback showed a greater reduction on different subscales of the Autism Treatment Evaluation Checklist (ATEC). Overall this study suggests that a treatment approach guided by QEEG based connectivity may be more effective in the treatment of autism as it allows for targeting and improvement of abnormal connectivity patterns in the brains of individuals with autism. 

Autism spectrum disorder (ASD) is characterized by abnormal visual processing of human faces. This deficit has been associated with hypoactivation of the fusiform face area (FFA). The aim of the present study was to train participants with ASD to achieve up-regulation of the FFA using rtfMRI-NF, to investigate the neural effects of FFA up-regulation in ASD. Five subjects with ASD participated as part of the experimental group and received contingent feedback to up-regulate bilateral FFA. Two control groups, each one with three participants with typical development (TD), underwent the same protocol: one group with contingent feedback and the other with sham feedback. Whole-brain and functional connectivity analysis using each fusiform gyrus as independent seeds were carried out. The results show that individuals with TD and ASD can achieve FFA up-regulation with contingent feedback. RtfMRI-NF in ASD produced more numerous and stronger short-range connections among brain areas of the ventral visual stream and an absence of the long-range connections to insula and inferior frontal gyrus, as observed in TD subjects.

This study explored practitioners perceptions of a neuro-feedback intervention in treating children with Autism Spectrum Disorder’s (ASD). Informants were a convenience sample of ten South African neuro-feedback practitioners registered with the Health Professions Council of South Africa (HPCSA). The data on their views on neuro-feedback treatment efficacy, with children with ASD, were collected by means of semi-structured in-depth interviews. Thematic analysis of the data suggest practitioners to perceive neuro-feedback treatment to enhance the social, mood, behaviour, academic life, and family functioning of children with ASD. Additionally, the practitioners perceived neuro-feedback treatment to assist in reducing anxiety among children with ASD.

Neurofeedback training approaches were investigated to improve behavior, cognition and emotion regulation in children with ASD. Thirteen children with ASD completed pre-/post-assessments and 16 NFT-sessions. The NFT was based on a game that encouraged social interactions and provided feedback based on imitation and emotional responsiveness. Bidirectional training of EEG mu suppression and enhancement (8-12 Hz over somatosensory cortex) was compared to the standard method of enhancing mu. Children learned to control mu rhythm with both methods and showed improvements in (1) electrophysiology: increased mu suppression, (2) emotional responsiveness: improved emotion recognition and spontaneous imitation, and (3) behavior: significantly better behavior in every-day life. Thus, these NFT paradigms improve aspects of behavior necessary for successful social interactions.

Previous studies examined the ability of low cost commercial headsets that can read brainwave patterns however there is limited research on how effective this is in concrete healthcare scenarios. To ensure that the neurofeedback therapy has great usability and user experience, the researchers have developed a Brain Computer Interface called FarmerKeeper that uses the subjects’ attention to control a runner video game. In the current study, 26 children with severe autism participated in a 10-week deployment study using the FarmerKeeper BCI. The pre and post-assessment evaluation showed that all children with ASD improved in their attention, attentional control and sustained attention. Furthermore, two of the children no longer showed attention impairments. These results show the potential benefits of using BCI video games in healthcare scenarios. 

The purpose of this study was to improve executive control in children with Autism Spectrum Disorder (ASD) using neurofeedback treatment. Seven ASD children received Neurofeedback (NFB) treatment and were compared to a waiting list control group who did not receive treatment. The results of the study showed that NFB reduced the children’s heightened theta/beta ratio by inhibiting theta activation and enhancing beta activation. After the treatment, the children’s executive control improved greatly relative to pre-treatment assessment on a variety of executive function tasks. Furthermore, there were improvements in children’s social, communicative and typical behavior compared to the control group. This study shows support for the potential use of neurofeedback to alleviate some of the basic executive function impairments in children with ASD.

The purpose of this study was to examine the effectiveness of Neurofeedback Therapy (NFT) in reducing symptoms in children with ASD by training the mirror neuron system (MNS) through the modulation of EEG mu rhythms. The MNS was their target of training as it provides a neurobiological substrate for understanding concepts in social cognition that are relevant to behavioral and cognitive deficits observed in ASD. The study consisted of two groups, ASD children and  typically developing (TD) children that underwent thirty sessions of NFT where they completed an eyes-open/-closed EEG session and a mu suppression index assessment before and after training. The parents also completed a questionnaire regarding their children’s pre- and post- training behavior. The results of the study showed improvements in the ASD children but not in the TD children. These results suggest that neuroplastic changes induced by the NFT can help to normalize any dysfunctional mirroring networks in children with autism.

Previous studies have found abnormal connectivity patterns between resting state networks in Autism Spectrum Disorder (ASD) but traditional treatments are limited and do not address the atypical network structure. The current study used real-time fMRI neurofeedback to train three brain nodes in participants with ASD where the abnormal connectivity correlated with symptom severity. The results of the study found that the training protocol produced significantly large, long-term changes in correlations at the network level and whole brain analysis found that the greatest changes were fixed on the areas that were being trained. These changes were not found in the control group. Furthermore, after training, the changes in ASD resting state connectivity were correlated to changes in behavior suggesting that neurofeedback therapy can be used to directly alter complex, clinically relevant network connectivity patterns such as those found in individuals with ASD. 

Two electrophysiological studies tested the hypothesis that operant conditioning of my rhythms via neurofeedback training can renormalize mu suppression, an index of mirror neuron activity, and improve behaviour in children diagnosed with autism spectrum disorders (ASD). In Study 1, eight high-functioning ASD participants were assigned to placebo or experimental groups before 10 weeks of training of the mu frequency band (8–13 Hz). Following training, experimental participants showed decreased mu power and coherence, increased sustained attention ability, and improved scores on subscales of the ATEC compared to the placebo group. Both groups showed improvement in imitation ability. In Study 2, 19 high-functioning ASD children underwent a similar procedure with verified diagnoses, a modified double-blind protocol, and training of the high mu band (10–13 Hz). The results showed decreases in amplitude but increases in phase coherence in mu rhythms and normalization of mu rhythm suppression in experimental participants compared to placebo. Furthermore, like Study 1, participants showed improvements in sustained attention and in ATEC scores but no improvements in imitation following training. This suggests that training of the mu rhythm can be effective in producing changes in EEG and behavior in high-functioning ASD children, but does not affect imitation behavior per se.

The researchers in this study wanted to explore, in depth, the changes of the relative power of EEG bands during prefrontal neurofeedback (NFB) training for individuals with autism spectrum disorder (ASD). The study consisted of 18 high functioning children with autism who completed 18 weekly sessions of NFB. The training program 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. The results of the study found a linear decrease of theta/beta ratio and a linear increase of relative power of gamma activity. They were also able to collect information about specific changes of EEG activity and correlations between changes of EEG and NFB indexes during training. This study indicates that prefrontal EEG training in neurofeedback mode can be an effective method of modifying EEG characteristics associated with ASD.

This study aimed to investigate the use of neurofeedback (NFB) to modulate brain activity resulting in behavior modification in children with autism spectrum disorder (ASD). 34 children with ASD were randomized into an active group that received NFB (via the Mente device) and a control group (via a sham device) Both groups completed training each morning for 45 minutes over a 12 week home based trial without any other interventions. To measure the effectiveness of the treatment, each participant completed a Pre and Post ASD questionnaire, qEEG assessment and a posturography test. The results of the study showed significant changes in several outcome measures for participants that received the NFB treatment but these changes were not detected in the control group. This study suggests that a short 12 week NFB training program using the Mente Autism device can result in significant changes in brain activity, sensorimotor behavior and overall behavior in children with ASD.

The researchers in this study wanted to investigate the effects of heart rate variability biofeedback (HRV-BFB), a method used to improve self-regulation of the autonomic nervous system (ANS), combined with Mu Synchrony neurofeedback (MRS-NFB) on individuals with Autism Spectrum Disorder. 15 children with ASD were assigned to either an HRV-BFB group (Group 1)  or a combined HRV-BFB + MRS-NFB group  (Group 2). Pre- and post-assessments were taken through EEG, HRV and parent-reported behaviors. The results of the study showed that group 1 had significant pre-post improvements in emotion regulation and social behavior while group 2 showed improvements in emotional lability and autistic behaviors. Group 2 also showed significant improvements in vagal tone indices of HRV over time. Group 1 showed an increase in mu suppression post training while Group 2 showed a decrease in mu suppression post training. These results suggest that using a combined approach of HRV-BFB + MRS-NFB may be more effective in enhancing HRV which can help to improve self regulation in children with ASD.

This study examined the effect of EEG neurofeedback on 6 male and 6 female patients with autism spectrum disorder. Each subject received 24 sessions of neurofeedback training over 3 months. Before and after the intervention, psychological data for measuring co-occurring psychopathological symptoms as well as behavioral data for measuring cognitive flexibility and emotion recognition abilities were recorded. No significant differences were found after the neurofeedback training protocol. There were also no significant sex differences found, but females reported slightly greater improvement than males on total symptoms. 

Autism Spectrum Disorder (ASD) requires immediate attention globally because the prevalence has increased in recent years. This paper is a preliminary case study in which a neurofeedback technique was used on an 8 year-old child with Asperger’s to determine its efficacy in reducing his pathological symptoms. The neurofeedback training aimed to enhance the sensorimotor rhythm (SMR) wave, inhibit the theta wave, and also inhibit the high beta wave. The training aimed to improve the boy’s behaviour, emotional expression, and language comprehension. After 20 sessions of neurofeedback, an improvement in sociability and speech/language was observed using the Autism Treatment Evaluation Checklist as well as the parent’s report. This provides important evidence for neurofeedback training in improving symptoms associated with Asperger’s. 

This paper reviews the symptoms of Asperger's Syndrome and highlights research findings with an emphasis on brain differences. Single channel assessment at CZ reveals patterns similar to those found in ADHD. Using 19-channel data, significant differences (z-scores > 2) were found in the amplitude of both slow waves (excess theta and/or alpha) and fast waves (beta) at various locations. Differences from the norm were most often found in mirror neuron areas (frontal, temporal and temporal-parietal). Low Resolution Electromagnetic Tomography Analysis suggested the source of the abnormal activity was most often the anterior cingulate. Other areas involved included the amygdala, uncus, insula, hippocampal gyrus, parahippocampal gyrus, fusiform gyrus, and the orbito-frontal and/or ventromedial areas of the prefrontal cortex. Correspondence between symptoms and the functions of the areas found to have abnormalities is evident and those observations are used to develop a rationale for using Neurofeedback. Porges' polyvagal theory is used to emphasize the need to integrate NFB with biofeedback (BFB), particularly heart rate variability training. We term this emerging understanding the Systems Theory of Neural Synergy. The name underscores the fact that NFB and BFB influence dynamic circuits and emphasizes that, no matter where we enter the nervous system with an intervention, it will seek its own new balance and equilibrium.

This paper summarizes a review of neurofeedback (NFB) training with 150 clients with Asperger’s Syndrome (AS) and 9 clients with Autistic Spectrum Disorder (ASD) seen over a 15 year period (1993–2008). The main objective was to investigate whether neurofeedback (NFB) made a significant difference in clients diagnosed with AS. Clients received 40–60 sessions of NFB, which was combined with training in metacognitive strategies and, for most older adolescent and adult clients, with BFB of respiration, electrodermal response, and heart rate variability. For the majority of clients, feedback involved decreasing slow wave activity (3–7 Hz), decreasing beta spindling (23 and 35 Hz), and increasing fast wave activity termed sensorimotor rhythm (SMR) (12–15 or 13–15 Hz). The most common initial montage was referential placement at the vertex (CZ) for children and at FCz (midway between FZ and CZ) for adults, referenced to the right ear. Metacognitive strategies relevant to social understanding, spatial reasoning, reading comprehension, and math were taught when the feedback indicated that the client was relaxed, calm, and focused. Significant improvements were found on measures of attention, core symptoms, achievement, and intelligence. The average gain for the Full Scale IQ score was 9 points. The positive outcomes of decreased symptoms of Asperger’s and ADHD (including a decrease in difficulties with attention, anxiety, aprosodias, and social functioning) plus improved academic and intellectual functioning, provided preliminary support for the use of neurofeedback as a helpful component of effective intervention in people with AS.

Contingent negative variation (CNV) is an indicator of attention and expectancy-related processes in the brain. An abnormal CNV amplitude has been found in neurodevelopmental disorders, but its role as a potential biomarker of autism spectrum disorder (ASD) remains unclear. This randomized controlled trial investigated how CNV changes following neurofeedback training. 21 adolescents with ASD underwent 24 sessions of slow cortical potential (SCP) neurofeedback training, and an ASD control group and received treatment as usual. CNV waveforms were obtained from a continuous performance test (CPT), which all adolescents performed before and after the corresponding 3-month long training period. The authors found that impulsivity moderates the effects of neurofeedback training on CNV. In the control group, the average CNV amplitude decreased or did not change after treatment as usual. In the experimental group, the CNV change depending on the severity of comorbid impulsivity symptoms. The average CNV amplitude of participants with low impulsivity scores decreased markedly, whereas the average CNV amplitude of participants with high impulsivity increased. The degree of impulsivity seemed to play a crucial role in CNV alterations following neurofeedback training.

This study investigated the effectiveness of neurofeedback for Autism with a broad range of assessments and physiological measures of brain functioning. 37 patients with ASD underwent 20 sessions of neurofeedback.. Improved ratings of ASD symptoms reflected an 89% success rate. Statistical analyses revealed significant improvement in the group who received Neurofeedback compared to a wait list control group. Other major findings included a 40% reduction in core ASD symptomatology, and 76% of the experimental group had decreased hyper-connectivity. Reduced cerebral hyperconnectivity was associated with positive clinical outcomes in this population. In all cases of reported improvement in ASD symptomatology, positive treatment outcomes were confirmed by neuropsychological and neurophysiological assessment. Evidence from multiple measures has demonstrated that neurofeedback can be an effective treatment for ASD. In this population, a crucial factor in explaining improved clinical outcomes in the experimental group may be the use of assessment-guided neurofeedback to reduce cerebral hyperconnectivity. 

This is a case study of a 5-year-old boy with ASD, who received a treatment of 26 sessions of infra-low frequency (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.

There is no specific cure for autism, therefore therapeutic guidelines are directed to improve the quality of life of people with autism by reducing symptoms and increasing functioning. During 2010 and 2011, neurofeedback training was administered to 10 children between the ages of 4-7, diagnosed as autism spectrum disorder (highly functional) with an unspecified impairment of speech development and trouble communicating. Treatment evaluation was done using changes in functioning estimates provided by parents, teachers, therapists’ and all other experts that were monitoring the child before, during and after the treatment, and using changes in electrophysiology. It was found that most changes were observed in behaviour (less aggressive, more cooperation, better communication), attention span and sensory motor skills. Further, based on the assessment provided by parents, teachers, therapists and other experts, all children accomplished a certain degree of improvement in their level of daily functioning. 

EEG-biofeedback has been reported to decrease autism spectrum disorder (ASD) symptoms, however previous studies did not control for nonspecific effects of EEG-biofeedback or distinguish participants who succeeded in influencing their own EEG activity. Therefore, the present study evaluated the effects of EEG-biofeedback in ASD in a randomized pretest-posttest control group design with blinded active comparator and a six month follow-up. Thirty-eight participants were randomly assigned to the EEG-biofeedback, skin conductance (SC)-biofeedback or waiting list group. EEG- and SC- biofeedback were similar and participants were blinded to the type of feedback they received. It was found that 54% of participants significantly reduced delta and/or theta power during EEG-biofeedback sessions and were identified as EEG-regulators. Amongst these EEG-regulators, no statistically significant reductions in ASD symptoms were observed. However, they demonstrated significant improvement in cognitive flexibility compared to participants who managed to regulate SC. No nonspecific effects of EEG-biofeedback were found. Overall, it was found that EEG-biofeedback is an effective too to regulate EEG activity and has specific effects on cognitive flexibility, though it did not result in any significant reductions in ASD symptoms.