A comprehensive set of treatment outcome measures was collected on each child one year after treatment had begun. These measures included: 1) parent and teacher ratings of inattentive and hyperactive/impulsive behavior using the Attention Deficit Disorder Evaluation Scale (ADDES), a widely used standardized behavior rating scale; 2) the children's scores on the TOVA; and 3) the children's Attention Index score, based on a QEEG scan. Each measure was collected twice: once when participants were still on medication and a second time after they had been off medication for an entire week.
The authors predicted that children in both groups would show behavioral improvements and "normalized" TOVA results when medication treatment was still in place, and would not differ from each other in terms of overall results. They also predicted that the improvements for the neurofeedback group would be significantly better upon the second outcome assessment, when the children were no longer receiving medication. (This prediction was based on prior research suggesting that neurofeedback training can yield sustained reductions in ADHD symptoms while medication-induced improvements typically last only as long as the child is on medication.) Finally, researchers expected that only children who received neurofeedback would show normalized Attention Index scores on the QEEG.
Outcomes when children were still on medication
As predicted, TOVA scores at the first outcome assessment were well within the normal range for both groups. In contrast to expectations, parent and teacher ratings of ADHD symptoms remained in the clinical range for children who had not received neurofeedback. For participants whose treatment included neurofeedback, however, parent and teacher ratings of ADHD symptoms were all in the normal range and were significantly better than ratings for the other participants. These results are shown below. (Note: Scores below 7 are considered to indicate significant difficulty. The numbers reported represent the average score for each group.)
Similar results were obtained on the outcome measures taken after the children had been without medication for an entire week. As before, children whose treatment had not included neurofeedback continued to show significant ADHD symptoms according to parent and teacher ratings. In addition, the TOVA results for these participants fell in the clinical range on 3 of the 4 subscales.
In contrast, parent and teacher ratings of the neurofeedback group all remained within the normal range, as did their TOVA results. Furthermore, the QEEG scan showed that the average Attention Index score for the neurofeedback group was also within the normal range, indicating that the cortical slowing characteristic of ADHD that was present at the beginning of treatment was no longer evident. As expected, the average Attention Index scores for participants not receiving neurofeedback continued to indicate significant cortical slowing.
Summary and Implications
These results provide compelling evidence that incorporating neurofeedback into a comprehensive treatment approach for ADHD can yield important benefits. As discussed above, only the participants whose treatment included attention training via neurofeedback showed behavioral improvement upon follow up, and these benefits were evident even after medication was discontinued. These children were doing substantially better --according to both parents and teachers--than participants who had not received neurofeedback. In addition, the pattern of cortical slowing that is found in many individuals with ADHD, and which is specifically targeted by neurofeedback, was no longer evident. This suggests that the gains associated with neurofeedback training cannot be attributed to the placebo effect, but instead reflect meaningful changes in EEG activity.
This is a very impressive set of findings. As with any study, however, it is important to recognize it's inherent limitations. First, it is surprising that no significant gains in parent and teacher ratings were obtained for the non-neurofeedback group, even when medication treatment was still in place. Recently published results from the MTA study document substantial benefits from medication treatment alone, and in combination with behavioral interventions, over a 14-month period. Based on these results, as well as results from other studies, improved symptom ratings from parents and teachers would have been anticipated. Because the same treatments were delivered to participants who also received neurofeedback, this does not call into question the incremental gains associated with neurofeedback. However, it does raise the question of whether such incremental gains would have been detected if the benefits provided by the other intervention components were as expected.
Several other cautions need to be noted. Because random assignment to treatment conditions was not feasible, one cannot rule out the possibility that parents who opted to include neurofeedback in their child's treatment were a more highly motivated group of parents, and this is why their children did better. After all, this was a time-consuming and expensive addition. The fact that there was no differential attendance in parent counseling sessions between the two groups mitigates these concerns, however. In addition, the EEG changes revealed by the QEEG scan make it unlikely that enhanced parent motivation alone could explain the differential treatment results. This is because these better results were associated with documented changes in neurophysiological processes known to be associated with ADHD, and it seems implausible that parents' motivation, or other extraneous factors , could have produced such changes.
Finally, it is important to emphasize that neurofeedback was delivered as part of a comprehensive treatment plan that included three other components. There is thus no basis for determining whether neurofeedback alone would have yielded positive results. And, although gains were sustained beyond the active use of medication, it is unclear whether these gains would persist without ongoing intervention. These issues would be important to address in subsequent research.
These cautions notwithstanding, this is an important study that makes a significant contribution to establishing a clear place for attention training using neurofeedback in the treatment of ADHD. One hopes that subsequent studies building on this impressive piece of work, and which incorporate important controls such as random assignment that were not possible in this investigation, will soon be forthcoming.