The ratio between frontal resting state EEG power in the theta and beta frequency bands (theta/beta ratio, TBR) was first associated with attention deficit hyperactivity disorder (ADHD) and later... Show moreThe ratio between frontal resting state EEG power in the theta and beta frequency bands (theta/beta ratio, TBR) was first associated with attention deficit hyperactivity disorder (ADHD) and later linked to various psychological functions and cognitive/emotional processes that rely on executive cognitive control. The aim of this thesis was to further investigate TBR as a potentially useful marker for executive/attentional control, particularly when studying threat selective attention and uncontrolled thoughts. It was found that high TBR was associated with more attention to mild than high threat and low threat-interference in visual-spatial tasks containing emotional information. TBR was also negatively related to self-reported attentional control. Frontal TBR was moreover significantly higher during uncontrolled thought compared to controlled thought and this effect was also found for functional connectivity of the ‘executive control network’, which was also correlated to the controlled versus uncontrolled thought effect on TBR. However, no evidence was found to suggest that TBR can be manipulated using Neurofeedback training. These findings provide clear indications of the neuropsychological functional nature of TBR and further support the notion that TBR reflects connectivity in brain networks involved in executive control processes. Show less
