In the realm of cognitive science, the quest to understand cognitive control has persisted for decades. Traditional notions of cognitive control have focused on inhibition through the prefrontal... Show moreIn the realm of cognitive science, the quest to understand cognitive control has persisted for decades. Traditional notions of cognitive control have focused on inhibition through the prefrontal cortex, but this dissertation challenges that perspective with a more comprehensive framework: The Metacontrol State Model (MSM). The MSM proposes that cognitive control emerges from the interplay between two opposing systems – one promoting flexibility and the other promoting persistence. These systems interact to shape our cognitive processing styles, thereby influencing our ability to effectively regulate our actions. This dissertation explores questions such as why individuals exhibit differences in cognitive control capacity and how state-related changes and trait-related predispositions impact cognitive control function. The overarching goal of this dissertation is to empirically test the MSM model and shed light on the factors that influence cognitive control. Through a series of experiments, it seeks to understand how altered states of consciousness, achieved through meditation techniques or serotonergic psychedelics, affect the balance between intentional and habitual processes. Additionally, it examines the extent to which individual trait biases serve as trans-diagnostic markers in various psychopathologies. This work comprises a literature review and six empirical articles. By integrating theory and empirical research, this dissertation takes us on a journey into the intricate world of cognitive control, shaping our understanding of how it influences our lives. Show less