A Meta-analysis of Quantitative EEG Power Associated With Attention-Deficit Hyperactivity Disorder

Abstract

A meta-analysis was performed on quantitative EEG (QEEG) studies that evaluated attention-deficit hyperactivity disorder (ADHD) using the criteria of the DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 4th edition). The nine eligible studies (N = 1498) observed QEEG traits of a theta power increase and a beta power decrease, summarized in the theta/beta ratio with a pooled effect size of 3.08 (95% confidence interval, 2.90, 3.26) for ADHD versus controls (normal children, adolescents, and adults). By statistical extrapolation, an effect size of 3.08 predicts a sensitivity and specificity of 94%, which is similar to previous results 86% to 90% sensitivity and 94% to 98% specificity. It is important to note that the controlled group studies were often with retrospectively set limits, and that in practice the sensitivity and specificity results would likely be more modest. The literature search also uncovered 32 pre-DSM-IV studies of ADHD and EEG power, and 29 of the 32 studies demonstrated results consistent with the meta-analysis. The meta-analytic results are also supported by the observation that the theta/beta ratio trait follows age-related changes in ADHD symptom presentation (Pearson correlation coefficient, 0.996, P = 0.004). In conclusion, this meta-analysis supports that a theta/beta ratio increase is a commonly observed trait in ADHD relative to normal controls. Because it is known that the theta/beta ratio trait may arise with other conditions, a prospective study covering differential diagnosis would be required to determine generalizability to clinical applications. Standardization of the QEEG technique is also needed, specifically with control of mental state, drowsiness, and medication.

The Cerebellum in Emotion Regulation: A Repetitive Transcranial Magnetic Stimulation Study

“…One of the possible reasons for this absence may be found in a recent meta-analysis which suggests that EEG ratios reflect stable trait-like properties and are less sensitive to state-related changes [48]. Clearly, more research is necessary to elucidate the exact contributions of state and trait properties of electric brain activity to the EEG ratios and the assumed relation with emotion regulation.…”

Electrophysiological biomarkers of diagnosis and outcome in neurodevelopmental disorders

“…Over the following decade, several studies supportive of the link between ADHD and the TBR were published by a handful of research groups, several of which had scientific conflicts of interest. In 2006, Snyder and Hall [28] published a meta-analysis that claimed an effect size of 3.08 for the TBR in ADHD, which they suggested was predictive of sensitivity and specificity of 94%. They subsequently published an empirical study that reported 87% sensitivity, 94% specificity, and 89% overall accuracy for ADHD diagnosis that was relatively invariant according to psychiatric comorbidity, developmental level (child, adolescent), sex, and racial group [29].…”

Baseline EEG theta/beta ratio and punishment sensitivity as biomarkers for feedback-related negativity (FRN) and risk-taking

“…These findings point towards a relation between baseline theta/beta ratio and behavioral inhibition, such that people with high theta/beta ratios are more impulsive and tend to take higher risks. This idea is all the more interesting since increased theta/beta ratio and theta power are common features of attention-deficit/hyperactivity disorder (ADHD; Clarke et al, 2002b, di Michele et al, 2005, Snyder and Hall, 2006, a condition that is characterized by impulsivity and risk taking (Ernst et al, 2003, Masunami et al, 2009, Sonuga-Barke et al, 2008.…”

“…It has been suggested that high theta/beta ratio mainly reflects increased power in the theta band (di Michele, Prichep et al 2005;Snyder and Hall, 2006). Rodent studies show that theta EEG is generated for a large part in the septo-hippocampal system (Vertes and Kocsis, 1997).…”