ORCID
http://orcid.org/0000-0003-0406-9024
Date of Award
Summer 8-15-2021
Degree Name
Doctor of Philosophy (PhD)
Degree Type
Dissertation
Abstract
Mindfulness training (MT) has been shown to be a promising psychological intervention that systematically fosters attention, awareness, and self-control capacities. Initial evidence has also suggested the utility of MT for enhancing cognitive function, yet mixed results regarding its cognitive benefits are observed, suggesting the need for more rigorous investigation. In particular, prior literature has not clarified the mechanism of action by which MT exerts its beneficial effects on cognitive function, given that most MT studies have examined cognitive function with a scattered selection of tasks, and without a coherent theoretical framework that can systematically explain potential cognitive improvement and their relation to brain functional changes. The current study aims to address these critical research gaps through a powerful discordant twin design with functional magnetic resonance imaging (fMRI), the first ever to be employed in MT research, to systematically evaluate MT effects on cognitive function and their neural mechanisms in both resting and task states. Importantly, this design not only reduces the potentially confounding control-group differences (monozygotic twins share the same genes), but also allow for stronger causal inferences on the mechanisms and effects of MT than previous studies that used poorly matched controls or no controls. The study had three specific aims. First, to examine the cognitive effects of MT with a comprehensive and theoretically-driven task battery that assesses general cognitive control capacity, as well as two modes of cognitive control (proactive and reactive) (Aim 1). Second, to exploit recent advances in network neuroscience in investigating the effects and mechanisms of MT at the level of large-scale brain networks during resting state (Aim 2). Third, to apply a novel multivariate pattern similarity approach in order to explore potential changes in neural activation patterns during cognitive task performance, comparing across twins to understand the neurocognitive effects of MT. The behavioral task performance provided some evidence of an improvement in proactive control function with medium effect sizes in the MT group. Furthermore, greater resting state within-network functional connectivity and integration were detected in the cinguolo-opercular/salience network associated with cognitive control in the MT group relative to the control group. Finally, within-person neural activation pattern similarity during cognitive task performance was lower in the MT group than in the control group, indicating putative systematic changes in the brain’s response to increased cognitive control demand after MT. Taken together, the results of this small-scale yet comprehensive investigation provide initial support for an enhancement in cognitive control function following MT in both brain and behavior, with some evidence suggesting a bias toward increased proactive control. Critically, these findings advance the understanding of MT effects and mechanisms on cognitive control and inform future investigations, development, optimization, and implementation of mindfulness training programs to enhance cognitive control both in public and in scientific domains.
Language
English (en)
Chair and Committee
Todd S. Braver
Committee Members
Deanna M. Barch, Ryan Bogdan, Joshua J. Jackson, Eric J. Lenze,
Recommended Citation
Tang, Rongxiang, "Examining Mindfulness Training Effects and Mechanisms on Cognitive Control" (2021). Arts & Sciences Electronic Theses and Dissertations. 2538.
https://openscholarship.wustl.edu/art_sci_etds/2538