The Role of Quantitative Electroencephalogram in the Diagnosis and Subgrouping of Attention-Deficit/Hyperactivity Disorder

Abstract

Attention-deficit/hyperactivity disorder (ADHD) leads to functional decline in academic performance, interpersonal relationships, and development in school-aged children. Early diagnosis and appropriate intervention can significantly reduce the functional decline caused by ADHD. Currently, there is no established biological marker for ADHD. Some studies have suggested that various indicators from the quantitative electroencephalogram (QEEG) may be useful biological markers for the diagnosis of ADHD. Until the 2010s, theta/beta ratio (TBR) was a biomarker candidate for ADHD that consistently showed high diagnostic value. However, limitations of TBR have recently been reported. Studies have demonstrated that phase-amplitude coupling, especially theta phase-gamma amplitude coupling, are related to cognitive dysfunction and may assist in the diagnosis of ADHD. As yet, the underlying mechanism is not clearly established, and the clinical efficacy of these biomarkers needs to be proven through well-controlled studies. Based on the heterogeneous characteristics of ADHD, subgrouping through QEEG plays a key role in diagnosis and treatment planning. Sophisticated, welldesigned studies and meta-analyses are necessary to confirm these findings.

Beta–Gamma Phase-Amplitude Coupling as a Non-Invasive Biomarker for Parkinson’s Disease: Insights from Electroencephalography Studies

“…This supports the crucial role CFC has in linking relevant brain regions, which results in sensory information integration and neural computation required in tasks such as attention, learning, working memory, and memory consolidation [ 20 , 43 , 44 ]. PAC is a means of sequence encoding, storage, retrieval of information, and communication between local networks, as well as macroscale systems in the brain [ 45 ].…”

Variations in Theta/Beta Ratio and Cognitive Performance in Subpopulations of Subjects with ADHD Symptoms: Towards Neuropsychological Profiling for Patient Subgrouping

“…The analysis of their performance in the working memory test revealed no difference between the ADHD and the control groups ( Figure 1 A); however, there was high heterogeneity in the performance of the group with ADHD symptoms. It is known that ADHD presents high etiological diversity, as well as variation in the neurophysiological correlates of this disorder, in different studies [ 21 , 25 , 26 , 27 ]. Therefore, we assessed whether our ADHD subjects were indeed heterogeneous through their performance in a working memory test.…”

“…There are articles reporting the classification of ADHD patients based on their qEEG [ 25 , 26 , 27 ]. Our work suggests that different neurophysiological correlates also imply different cognitive affectation in ADHD patients.…”

“…Various studies report an increased theta/beta ratio in children and adolescents with ADHD [ 2 ]. However, this approach is not always optimal, and due to the heterogeneity found in the neurophysiological correlates of ADHD, some groups have proposed the idea of subgrouping ADHD patients according to their brain activity [ 25 ]. For example, a study performed on Thai children with ADHD reports different subgroups of patients considering the analysis of theta-relative power based on their brain mapping performance.…”

State of the art and new directions of Quantitative Electroencephalography use in Differential Diagnosis of ADHD

“…Thus, although it does not constitute a diagnostic test per se for ADHD (Adamou et al, 2020), the QEEG could play a relevant role in its differential diagnosis, as well as other tests (Chiarenza, 2021;Lenartowicz & Loo, 2014;McVoy et al, 2019), and provide clinical information relevant to the patient's approach (Loo & Makeig, 2012). In addition, several studies have found patterns (Arns et al, 2008;Bong & Kim, 2021;del Campo et al, 2012) using the EEG spectral analyses that could -or could not-be considered as the electroencephalographic endophenotypes of ADHD and that, despite not having a clear diagnostic utility, would have a classificatory and even a prognostic utility. (Arns, 2012b;Arns & Olbrich, 2014;Slater et al, 2022).…”