A CONTROLLED STUDY OF
THE EFFECTS OF EEG BIOFEEDBACK
ON COGNITION AND BEHAVIOR OF CHILDREN
WITH ATTENTION DEFICIT
AND LEARNING DISABILITIES
Michael Linden, Ph.D.; Thomas Habib, Ph.D. Vesna Radojevic, Ph.D.
Mission Psychological Consultants
Attention Deficit Disorder (ADD) is the most common psychiatric disorder of childhood. This disorder is estimated to impact approximately 5-10 percent of all children. Learning Disabilities (LD) have been described in the literature since the onset of formal education began. Recently, a biological basis for ADD and LD was postulated. These disorders are currently believed to be inherited. Together with the associated disorders of Hyperactivity (ADHD), and Oppositional Defiant Disorder (ODD), it is estimated that almost 20 percent of all children are affected. The ramifications of these disorders are widespread, encompassing academic performance, difficulties with parenting, and poor peer relationships.
EEG Biofeedback treatment for Attention Deficit Disorders with or without hyperactivity and Learning Disabilities has emerged as an important component in enhancing attention, cognitive functioning and behavior. Reports by several researchers of significant increases in IQ scores, grades and educational test scores suggest promise for this new procedure (Lubar, 1992, 1984; Tansey, 1991, 1990, 1983). However, all of the previous studies of EEG Biofeedback treatment with children lack appropriate control conditions and suffer from extremely small sample sizes.
The current study utilized a two group experimental design, an EEG Biofeedback treatment was compared to a waiting list control group, in order to evaluate the effects of EEG Biofeedback training. Eighteen children diagnosed with ADD, ADHD or LD, according to DSM-III-R criteria and lowa-Conners Behavior Rating Scales, between the ages of 5 and 15 were randomly assigned to one of the two groups. None of the subjects in either condition received psychotherapy or pharmacological treatment during their participation in the study. All subjects were measured at pretreatment and posttreatment on a battery of tests including measures of intellectual functioning (Kaufman-Brief Intelligence Test/K-BIT Kaufman & Kaufman 1990) and parental behavioral reports of inattention, hyperactivity, aggressive and defiant behaviors (SNAP Rating Scale; Swanson, Nolan & Pelham, 1981 and Iowa-Conners Rating Scale, Milich, Loney & Landau, 1982).
The treatment group (N=9) received 40 sessions, twice weekly of EEG Biofeedback. The EEG Biofeedback consisted of computerized Autogenic A620 and Biocomp instrumentation using a bipolar placement at CZ and Pz The EEG Biofeedback protocol reinforced the enhancement of Beta brain waves (16-20 Hz) and the suppression of Theta brain waves (4-8 Hz) Muscle tension artifact (EKG) was also suppressed as part of this training protocol. The control waiting list group (N=9) received no EEG Biofeedback treatment. The EEG brain waves were shaped based on the individual subject's performance.
Multivariate analysis of variance (MANOVA) and analysis of variance (ANOVA) were conducted on the pretreatment dependent measures of IQ, ADD, ADHD, and ODD behavior. The MANOVA and ANOVA were not significant, reflecting that all of the dependent measures were similar across the conditions at pretreatment. In addition, the demographic variable of age was examined with ANOVA and chi-square, and again the two groups did not significantly vary on any of the dependent or demographic variables indicating that the groups were equivalent at entry into the study on these variables.
At posttreatment the experimental group demonstrated a significant mean increase Composite IQ of nine points greater than the control group (p<.05; see Table 1). The treatment group also significantly reduced inattentive behaviors as rated by parents (p<.05); see Table 2). No significant differences were found for hyperactive or aggressive and defiant behaviors. However, hyperactive behaviors declined in the experimental group to within normal limits after treatment and aggressive-defiant behaviors also decreased more than in the control group Furthermore, the subjects in the experimental group diagnosed with only LD had an average IQ increase of 20 points. However the number of LD subjects was not large enough to reach statistical significance. Since there were several dependent measures in this study, the risk of Type 1 error is greater, and the results should be interpreted with caution.
TABLE 1: Means and Standard Deviations for K-BIT IQ
Changes Pre and Post EEG Biofeedback Treatment
Experimental Group Control Group
M SD M SD
Pre 101.1 26.2 99.1 13.2
Post 110.4 * 21.2 100.0 10.1
TABLE 2: Means for Pre and Post Parent Ratings of
Inattentive, Hyperactive and Aggressive-Defiant Behaviors
Inattention 11.33 8.11* 12.00 12.44
Hyperactivity 8.56 4.77 9.83 9.00
Aggressive/ 5.66 3.00 8.45 7.45
The results of this study lend support to previous research studies of Lubar (1984 1976) and Tansey (1991, 1990, 1983) for the effectiveness of EEG Biofeedback as a treatment for ADD and LD children. This study included a larger sample size than most of the previous studies: large enough to have adequate power to evaluate significant differences in IQ and inattentive behavior. The current study also utilized better controls including: 1) a control group which received no treatment of any kind 2) consistent bandpasses of EEG biofeedback (Beta/Theta), 3) the same length of treatment (number of sessions), and 4) reliable multiple dependent measures to assess improvement.
The significant improvements in intellectual functioning as measured by increases in IQ scores, may be the result of the treatment having an impact on the subjects' ability to attend and concentrate, hence enhancing performance on the subtests which comprise the K-BIT rather than actually increasing their intellectual potential. The findings of this initial controlled study of EEG Biofeedback effect on ADD and LD children are quite promising, even though the cognitive (IQ) increases are smaller than the previously reported findings in non-controlled studies.
The application of EEG Biofeedback may prove to be an important new treatment component for Attention Deficit Disorder and Learning Disabled children. Further research utilizing double-blind placebo designs and larger sample size are needed to support and replicate the finding. In addition, larger sample sizes are needed to determine if this treatment protocol is more effective with children having only ADD, LD or a combination of ADD, ADHD and LD.
Communication should be addressed to:
Michael K. Linden, Ph.D.
ADD Treatment Centers
30270 Rancho Viejo Road, Suite C
San Juan Capistrano, CA 92675
4199 Campus Drive, Suite 550
Irvine, CA 92612
701 Palomar Airport Road, 3rd Floor
Carlsbad, CA 92009