Assessing attention deficit hyperactivity disorder via quantitative electroencephalography: An initial validation study.

Abstract

Spectral analysis of the electrophysiological output at a single, midline prefrontal location (the vertex) was conducted in 482 individuals, ages 6-30 years old, to test the hypothesis that cortical slowing in the prefrontal region can serve as a basis for differentiating patients with attention deficit hyperactivity disorder (ADHD) from nonclinical control groups. Participants were classified into 3 groups (ADHD, inattentive; ADHD, combined; and control) on the basis of the results of a standardized clinical interview, behavioral rating scales, and a continuous performance test. Quantitative electroencephalographic (QEEG) findings indicated significant maturational effects in cortical arousal in the prefrontal cortex as well as evidence of cortical slowing in both ADHD groups, regardless of age or sex. Sensitivity of the QEEG-derived attentional index was 86%; specificity was 98%. These findings constituted a positive initial test of a QEEG-based neurometric test for use in the assessment of ADHD.

Neurofeedback for ADHD

“…In addition, the theta/alpha and theta/beta ratios have been claimed to be reliable measures differentiating ADHD and control children. 19 Meanwhile, several studies using cluster analysis have reported distinct EEG-defined subgroups within their ADHD samples, 20,21 comprising among others a cortical hypoarousal subtype (increased relative theta and theta/beta ratio), a subtype indicative of a maturational lag, and a hyperarousal subtype (excess of beta activity). Because of more recent results, however, doubt has been cast on claims that the theta and beta ratio may serve as simple and reliable QEEG markers for ADHD, which has led to a major paradigm shift toward neurophysiologic subtyping.…”

The Effect of Psycho-Educational Therapy on Electroencephalographic Biofeedback Scores in Attention Deficit Hyperactivity Disorder

“…To our knowledge, only few neurofeedback studies focus on brain activity modification itself and EEG data are rarely available. Initial values for Theta/Beta ratio at first session were not similar to those reported by Monastra et al in 1999 for a group of ADHD children of the same age (Monastra et al, 1999). In this study, authors used a Theta/Beta value that was at least 1.5 SD higher than the value reported for normal age peers as a cutoff point for ADHD diagnosis.…”

“…In some studies focusing on neurofeedback methodology, it was observed that when electrodes were fixed frontally, where more theta and less beta activity in patients with ADHD is found, then artifacts by eye movements may be a significant risk (Mann et al, 1992;Lubar et al, 1995;Chabot & Serfontein, 1996). For this reason it is suggested that electrodes are placed in a more central position at C3f (= halfway between C3 and F3) and C4f (= halfway between C4 and F4) (Monastra et al, 1999). In the current study electrodes were positioned at C3 or C4 positions (a bit posteriorly in relation to the positions described previously), whereas in the study of Song et al Theta/Beta ratios were recorded in all 30 regions defined by the International 10/20 system but not over C3-C4 or C3f-C4f (Song et al, 2005;Monastra et al, 1999).…”

“…For this reason it is suggested that electrodes are placed in a more central position at C3f (= halfway between C3 and F3) and C4f (= halfway between C4 and F4) (Monastra et al, 1999). In the current study electrodes were positioned at C3 or C4 positions (a bit posteriorly in relation to the positions described previously), whereas in the study of Song et al Theta/Beta ratios were recorded in all 30 regions defined by the International 10/20 system but not over C3-C4 or C3f-C4f (Song et al, 2005;Monastra et al, 1999). A second explanation may be the difference in the methodology used and more precisely in the calculation of the mean Theta/Beta ratio.…”

The European ADHD Guidelines Group replies:

“…For instance, the developmental stability of EEG frequency band alterations in ADHD from childhood into adulthood have been questioned 11,38,39 , while the most commonly observed ADHD effects with regard to evoked brain responses relate to early rather than later components not targeted in current neurofeedback protocols. Therefore, the rationale for theta-beta feedback have been very critically discussed (e.g., 9,40 ).…”