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EEG Biofeedback Training for Hyperactivity,
Attention Deficit Disorder, Specific Learning Disabilities,
and Other Disorders
Siegfried Othmer, Ph.D., and Susan F. Othmer
March, 1989
Page 3 of 5
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 Ongoing Clinical Work with EEG Biofeedback
The protocol discussed above, namely reinforcement of 12-15 Hz (SMR) or of the beta spectral band (15-20 Hz), with simultaneous inhibition of low frequency, typically 4-7 Hz, has been used extensively in clinical settings. For research purposes, experimental methodology in a clinical setting suffers from the fact that controlled studies are not generally possible with paying patients. In particular, it is not professional to subject such patients to contingency reversals or non-contingent feedback, or to some other test of placebo or non-specific effects. On the other hand, the data are numerous, and hence gain a certain credibility from the sheer weight of evidence. These continuing clinical evaluations are summarized briefly in the following, to the extent that we are aware of them.
 Epilepsy
The technique has been used extensively over the years for drug refractory and other cases of epilepsy. Some users have adopted the strategy of reinforcing beta (e.g. 15-18 Hz) instead of SMR (12-15 Hz), with apparently equivalent results. Also, reinforcement strategies have been changed to enhance the rate of task acquisition. Reduction or elimination of anticonvulsant medication has been possible in numerous cases. The acquisition of the new EEG pattern also appears to be permanent in many cases, although some patients will return for refresher sessions on a bi-monthly basis.
The technique has also shown itself to be helpful for other consequences of epilepsy, such as the emotional, social and cognitive deficits. With respect to psychosocial aspects, results were mixed in the recent Lantz and Sterman study. We may speculate that the SMR-enhancement protocol may be more effective with a motor symptomatology, and that psychosocial performance can be expected to improve in cases where there is limbic system involvement. In the latter case, the enhancement of low beta (15-18 Hz) may be a preferable training goal.
Hyperactivity and Attention Deficit Disorder
Clinical experience in the treatment of hyperactivity and attention deficit disorder, as well as specific learning disabilities, extends to about 2000 children. Residual type (adult) attention deficit disorder has been successfully treated as well. As in the case of epilepsy, training has been done preferentially with the most challenging cases, namely those which are not adequately managed with medication, and those presenting behavioral problems (conduct disorder). In some clinical settings, the experimental protocol has shifted to the exclusive training of the 15-18 Hz spectral band, to the exclusion of the SMR. The symptoms of hyperactivity subside readily in either case, although a rigorous comparative study would be of interest. The success of this strategy tends to imply that inadequate arousal and poor desynchronization of the cortex may underlie both the attentional and the motor deficits. (On the other hand, perhaps one should not overemphasize the distinction, since typical filters will not exhibit high rejection of the neighboring band.) Whereas some degree of treatment success is reasonably predictable for these conditions, training may extend to 50 or more sessions. A significant effect of beta enhancement training (concurrent with theta suppression) on conduct disorder has been observed by several practitioners.
Variations of the "standard" paradigm of training to enhance 12-15 Hz or 15-18 Hz amplitudes with simultaneous inhibition of excess 4-7 Hz have also been reported by other clinical workers. Tansey trained to augment SMR with audio feedback to the patient. He also employed a midline placement for the electrode, rather than over sensorimotor cortex. In an early reported study, both EMG and EEG biofeedback were evaluated with one patient. EMG biofeedback was used successfully to reduce motoric activity level to below that previously achieved with Ritalin. Further, ADD was no longer diagnosable after the EMG training. Subsequent SMR enhancement training effected remediation of the developmental reading disorder, and the child's ocular instability (Tansey, 1983).
Learning Disabilities and Dyslexia
EEG biofeedback has now been evaluated in realistic settings in two separate studies: first, that of the Lubars in Tennessee schools (already referred to), and second, a study by J. Carter and H. Russell in Texas schools (See Lubar, 1989). In the former, training was carried out by resource teachers or school psychologists. In the Texas study, indications were that left hemisphere beta enhancement led to improvements in verbal IQ, as measured by the WISC-R, whereas beta enhancement of the right hemisphere led to improvement in the performance measures of the WISC.
Tansey has also evaluated the training for specific learning disabilities, i.e. those apparently unrelated to attentional deficits. In those cases (4) in which the verbal and performance IQ (WISC-R) differed by more than 15 points, EEG training effected an improvement by no less than 60% in the lower of the two scores. This demonstrated 1) that midline placement is effective in training either hemisphere, and 2) that the training effects preferential remediation of deficits (Tansey, 1985).
In a recent study (Tansey, 1990), 24 learning disabled children were given EEG training and evaluated with the WISC-R. Here the training paradigm included inhibition of excessive 7 Hz amplitudes via verbal cues. Eleven of the subjects had been diagnosed neurologically impaired, eleven were judged perceptually impaired, and two were diagnosed with ADD. Training sessions were conducted weekly for 30 minutes. The average number of training sessions was 28. The average increase in verbal IQ was found to be 16 points, in performance IQ 19 points, and in full scale IQ, 19 points. When either verbal or performance was in deficit with respect to the other by more than 12 points, the improvement in IQ scores for the area in deficit was twice that of the other.
The available evidence suggests that the EEG biofeedback technique has an impact on certain specific learning disabilities, while others remain relatively unaffected. Some cases of dyslexia, for example, respond readily to training, while others remain resistant. The large variety of brain lesions which could be responsible for these specific deficits may account for this variability in response to training. The evidence is tantalizing, and demanding of more rigorous study. The use of the technique for learning disabilities constitutes perhaps its most widespread application at the present time. However, much of this work has not been published.
Sleep Disorders
There is a close connection of the entire history of EEG biofeedback for control of epilepsy with the study of sleep disorders. The identification of the SMR rhythm with sleep spindles has already been referred to. It was also noted that enhancing the SMR rhythm by means of biofeedback training resulted in more normal, peaceful sleep in individuals referred for treatment of seizure disorders and those referred for other conditions such as primary unipolar depression. In clinical studies, the effectiveness of SMR and low-beta training for treatment of insomnia has been demonstrated.
Treatment for hyperactivity in young children will often lead to the early report that sleep walking, night terrors, bedwetting, bruxism (teeth grinding), and sleep-talking or walking have stopped. Treatment for depression will often lead to the report that quality of sleep is improved.
Minor Traumatic Brain Injury
The EEG biofeedback technique appears to be quite effective in recovering function in cases of minor brain injury, particularly in those cases where the organic damage is relatively minor and diffuse (e.g. ischemia or anoxia), and may not even be discernible by conventional imaging techniques. Examples of brain injury where the EEG training has been effective include concussion, whiplash, central nervous system infection, chemical CNS injury, stroke, and cerebral palsy. Clinical experience now extends to more than 500 cases of closed head injury.
The chronic effects of concussion appear to be subject to remediation by EEG training. These include headaches, dizziness, fatigue, poor concentration and memory, irritability, mood swings, insomnia, poor hearing and vision, slurred speech, anxiety and depression. It will not have escaped notice that a number of the other conditions discussed, such as epilepsy and hyperactivity, may be caused by minor closed head injury as well. The prominence of birth trauma in the medical histories of children referred for hyperactivity, ADD, and learning disabilities renders it only too likely that these conditions are frequently attributable to this mechanism of brain injury. (This is not to deny the manifest contribution of heredity.) Hence, the story of EEG biofeedback is to a large extent the story of minor brain injury in its inclusive sense.
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