STATES OF WAKEFULNESS, MENTATION AND CONSCIOUSNESS ARE ACCOMPANIED BY THE CHARACTERISTIC ELECTRICAL ACTIVITY OF THE THALAMOCORTICAL MECHANISMS OF THE HUMAN BRAIN

This study explores the electrical activity of the thalamocortical system in the human brain during states of wakefulness, relaxation, and cognitive effort. Using non-invasive electroencephalography (EEG), we examined the dynamics of brain waves, particularly the alpha rhythm (8-13 Hz), and its variations during mental tasks. We introduced a novel metric, Quotus alpha (Qa), to quantify the asymmetry and slope of alpha waves. Our research included 26 participants across diverse groups: healthy adults, individuals with neurological abnormalities, and children diagnosed with ADHD. Results revealed distinct patterns of alpha wave asymmetry, with steeper left-sided slopes during cognitive tasks, correlating with increased mental effort and altered delta activity. These patterns differed notably between adults and children, suggesting developmental and functional distinctions in thalamocortical processing. The findings support the role of iterative thalamocortical interactions in cognitive processes, emphasizing their adaptability and complexity. In healthy adults, alpha dynamics reflected higher cognitive performance and recruitment of neural resources. Conversely, the atypical EEG patterns observed in children with ADHD and individuals with neurological conditions highlight potential diagnostic and therapeutic implications. This study enhances our understanding of the neural underpinnings of attention, cognition, and neurodevelopmental disorders while providing new methodological insights into EEG analysis.