Neurofeedback for Autistic Spectrum Disorders: Promising Results in a Small Sample

On January 23, 2009, by Christopher Fisher, PhD

Autistic Spectrum Disorders (ASD) are characterized by significant deficits in social skills, attention/concentration, and communication, as well as emotional, cognitive, and behavioral impairments. Examples include Autism, Asperger’s Disorder, and Pervasive Developmental Disorder Not Otherwise Specified.  I am not aware of any treatment that can “cure” ASD. Current therapies focus on symptom reduction, behavioral and social skills training, and quality of life enhancements.

Readers not familiar with neurofeedback will want to might want to first review Neurofeedback: Brainwave Therapy to better understand the current report.

Kouijzer et al. (2009)* investigated the effects of neurofeedback in a group of 12 male and 2 female children (ages 8-12 years with a average age of 10.1) diagnosed with Pervasive Developmental Disorder, Not Otherwise Specified. Seven of 14 participants underwent neurofeedback training (“experimental group”), while the remaining persons  received no treatment (“wait-list control group” or just “control group”).  Experimental groups are often compared to control groups in research to help control for experimental confounds (variables that can seriously jeopardize the results of  study),  placebo effects (the effects of participants belief that their health will improve even if given a sham treatment), and to determine the magnitude of a treatment.    A non-randomized, pre-test/post-test design (the same set of tests were given before and after the experiment) was used. Wait-list control and experimental participants were “matched.”   Matched designs attempt to make comparisons between subjects who are judged to be more or less equivalent in the variables under investigation.  For example, an experimenter might “match” subjects with similar levels of depression when testing a new  anti-depressant so that the actual effects of the drug can more accurately estimated.

This part gets a little more technical. Based on previous research, Kouijzer et al. developed an argument that neurofeedback might improve abnormal theta-to-beta ratios in persons with ASD.  Specifically, the researchers hypothesized that a classic neurofeedback protocol called “SMR training”  (inhibit frequencies less than 10Hz and enhance 12-15 Hz [often called “low beta” or “SMR”] along the cerebral motor strip using a 2 channel, C3/C4 protocol), might improve executive functioning (attention/concentration, mental flexibility, speed and efficiency, and goal setting) and communication abilities. (NOTE: see an updated on the protocol used in this study in the comments section below).  Don’t worry about the frequency bands and names – just know that specific electrical energy of the brain was either enhanced or inhibited. The researchers reasoned and cited existing evidence that SMR training activates an important region of the brain called the anterior cingulate cortex that is responsible for cognitive and emotional regulation (a deficit in Autistic Spectrum Disorders). It is worth noting that elevated theta-to-beta ratios can occur in and are believed by some to be a defining feature of the EEG in attention deficit hyperactivity disorder (ADHD).

Outcome measures included executive, social, and neurophysiological (QEEG) levels of functioning.  All persons in the experimental group received 40 neurofeedback sessions (this is a fairly average amount of sessions in my experience).  The researchers reported impressive results following the completion of neurotherapy. Experimental group participants realized statistically significant improvements in the following areas: sustained auditory selective attention (30%), inhibition of verbal responses (55%), inhibition of motor responses (15%), set shifting (57%), concept generalization (50%), and planning ability (37%). Significant improvements were also found in communication (17%), general communication (14%), social interaction (16%), and typical behavior (9%). Percentages reflect improvement in the experimental group at their post-assessment compared to their pre-assessment.

No statistically significant improvements were found in areas of verbal and visual memory and sustained attention; however, the authors’ noted that many of the participants did not exhibit deficits in these areas at the start of the study.   Additionally, the post-QEEG (brainmap) did not show statistically meaningful changes when compared to the control group despite obvious treatment benefits. A current debate exists in the field regarding pre-post QEEGs and the factors that can account for changes or lack thereof.  This is a highly technical discussion that I will not address in this report.

The fact that Kouijzer et al. obtained significant results with a relatively small number of participants suggests large treatment effect sizes (the magnitude of the treatment) with limited variability of test scores (participants had similar gains) following neurofeedback. One potential confound includes that participants’ IQ fell in the average range, which may not be representative of some persons with ASD. The researchers reported, however, a wide range of IQ scores in the experimental and control groups (73-111 and 82-199, respectively).

Part 2 of this research investigates whether treatment gains realized in the current study were maintained 1 year later. Part 2 of this article is posted below..

*Kouijzer, M., de Moor, J., Gerrits, B., Congedo, M., van Schie, H. (2009). Neurofeedback improves executive functioning in children with autism spectrum disorders. Research in Autism Spectrum Disorders, 3, 145-162.

A One Year FollowUp od Neurofeedback for Austic Spectrum Disorders

On January 31, 2009, by Christopher Fisher, PhD

This current report extends the initial findings of  “Neurofeedback For Autistic Spectrum Disorders: Promising Results In A Small Sample” to a 1 year follow-up of the same participants with Autism Spectrum Disorders (ASD).  Recall from the initial study that participants with ASD experienced statistically meaningful improvements in a variety of executive functioning, social, and behavioral areas following 40 neurotherapy sessions.

For clarity, “pre-test”  or “post-test” scores refer to the initial report.  “Follow-up” scores refer to the 1 year follow-up study cited below.  Also, readers may want to review the first report for detailed information on the specific treatment gains realized after neurotherapy before reading this current article.

Kouizzer et al. (in press)* re-administered the identical Autism, cognitive, and psychosocial tests used in the original study to determine if symptom improvement persisted for 1 year following neurotherapy.  No significant performance decreases were found in executive functioning scores at follow-up compared to post-test.  Moreover, “auditory selective attention” continued to improve at statistically significant rates since the completion of the last study, and “inhibition of motor responses” nearly reached significance for continued improvement 1 year later.  Overall, the data suggests that all initial gains in executive function were maintained 1 year later, and that some areas of executive function may develop further after neurotherapy.

Similarly, gains in general communication, communication, social interaction, and typical behavior were maintained at 1 year follow-up when compared to post-test scores.   Compared to pre-test scores, participants exhibited statistically meaningful improvement in non-verbal communication skills (new finding) at follow-up, while improvements in general communication were no longer realized (an additional new finding).

In summary, 40 sessions of neurotherapy produced lasting improvements (i.e., 1 year) in a variety of executive functions, social and communication skills, and positive behaviors.

I need to also mention that all too often long-term follow-up data is neglected in neurofeedback research for various reasons, including time and financial investments; consequently, Kouijzer et al.’s efforts are certainly praise worthy.  In fact, the field of neurofeedback needs many more quality studies that include long-term follow up to achieve mainstream acceptance and to be eligible for insurance coverage.

One final note that may interest neurotherapists:  The researchers clearly stated that neurofeedback comprised a single channel C4 theta/SMR protocol.  This effectively clarifies questions I raised about the actual protocol used in this research.



*Kouijzer, M., de Moor, J., Gerrits, B., Buitelaar, J., & van Schie, H. (In Press). Long-term effects of neurofeedback treatment in autism.  Research in Autism Spectrum Disorders.