Neurofeedback as a therapy component for Autism Spectrum Disorders (ASD)
What is ASD?
Autism Spectrum Disorder (ASD) is a profound developmental disorder that begins in (early) childhood. Diagnostic criteria include deficits in social communication and interaction, limited repetitive behavioral patterns such as inflexible holding on to routines and hyper-/ or hypoactivity to sensory stimuli. Functions of speech, visual spatial skills and movement coordination are often affected by developmental limitations or delays. The term spectrum disorder indicates that different forms of autistic disorders can be distinguished, especially early childhood autism, atypical autism and Asperger syndrome.
Indicating a prevalence for ASD is not trivial, as there is no uniform approach or criteria, and numbers are not available for all regions worldwide. It may be possible to estimate a prevalence of approximately 1.5% for ASD in industrialized countries (see literature 1). The clinical appearance of ASD changes considerably over the life span from infancy to adulthood, both in core symptoms and compensation strategies.
Neurofeedback as an option in a multimodal therapy approach
Neurofeedback can be used as a block of therapy for those affected by the autism spectrum. Recent research into the neurophysiology of autism spectrum disorders has shown that autistic individuals have different connectivity networks and specific regions of hyper- and hypo-connectivity than healthy subjects in comparison with a control group (see literature 2). Other theories, such as those on altered mirror neuron activity, or hypotheses on the Theory of Mind and the Polyvagal Theory, also emphasize neurological differences for patients with ASD.
The effect of Neurofeedback is alteration of dysregulated brain activity. It is known from studies that patterns of resting EEG and evoked potentials in patients with ASD differ from those of healthy populations. The effect of neurofeedback on the brain has been confirmed in a recently published study. The functional connectivity (communication between neurons) in the brains of subjects was examined by fMRI before and after a 30-minute neurofeedback session. After the neurofeedback session, an increased connectivity of neurons in the brain was found (see literature 3). From these results it can be deduced, among other things, that neurofeedback not only has a positive effect on the symptoms of illnesses but can also cause effects in the brain and thus possibly change connectivity patterns in the long term, such as those that occur in chronic pain. These results support the hypothesis of neurofeedback as a method of improving the self-regulating capacity of the brain.
State of Research: Neurofeedback in Autism Spectrum Disorders
Due to the functional neuroanatomical abnormalities in patients with ASD, neurofeedback can be an effective treatment method for reducing the symptoms of dysregulation (see literature 4). This hypothesis is strengthened in a controlled study, in which ASD patients had a reduction of cerebral hyper-connectivity after 20 sessions of Neurofeedback as well as a significant reduction of the symptoms by the treatment (see literature 5). It is also shown that neurofeedback in combination with other treatment methods is a possibility to improve the patients' performance (see literature 6). A follow-up study shows that 12 months after the Neurofeedback treatment, the obtained improvements are still present (see literature 7), which indicates that Neurofeedback not only helps with the current symptoms, but it also helps the brain to improve the executive functions.
Previous work (literature 8) and a recent review of the existing literature concludes that neurofeedback is a promising treatment for autism and cites the evaluation of numerous studies and case reports (see literature 9). However, it is also noted that further studies, particularly controlled and randomized studies, should be conducted to evaluate further details of treatment conditions.
Literature
1. Fombonne, E. Editorial: The rising prevalence of autism. J. Child Psychol. Psychiatry Allied Discip. 59, 717–720 (2018).
2. Holiga, Š. et al. Patients with autism spectrum disorders display reproducible functional connectivity alterations. Sci. Transl. Med. 11, (2019).
3. Dobrushina, O. R. et al. Modulation of Intrinsic Brain Connectivity by Implicit Electroencephalographic Neurofeedback. Front. Hum. Neurosci. 14, 1–13 (2020).
4. Thompson, L., Thompson, M. & Reid, A. Functional neuroanatomy and the rationale for using EEG biofeedback for clients with Asperger’s syndrome. Appl. Psychophysiol. Biofeedback 35, 39–61 (2010).
5. Coben, R. & Padolsky, I. Assessment-Guided Neurofeedback for Autistic Spectrum Disorder. J. Neurother. 11, 37–41 (2008).
6. Knezevic, B., Thompson, L. & Thompson, M. Pilot Project to Ascertain the Utility of Tower of London Test to Assess Outcomes of Neurofeedback in Clients with Asperger’s Syndrome. J. Neurother. Investig. Neuromodulation 14, 3–19 (2010).
7. Kouijzer, M. E. J., de Moor, J. M. H., Gerrits, B. J. L., Buitelaar, J. K. & van Schie, H. T. Long-term effects of neurofeedback treatment in autism. Res. Autism Spectr. Disord. 3, 496–501 (2009).
8. Coben, R., Linden, M. & Myers, T. E. Neurofeedback for autistic spectrum disorder: A review of the literature. Appl. Psychophysiol. Biofeedback 35, 83–105 (2010).
9. Van Hoogdalem, L. E., Feijs, H. M. E., Bramer, W. M., Ismail, S. Y. & Van Dongen, J. D. M. The Effectiveness of Neurofeedback Therapy as an Alternative Treatment for Autism Spectrum Disorders in Children: A Systematic Review. J. Psychophysiol. (2020). doi:10.1027/0269-8803/a000265