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Date of Award
Doctor of Philosophy (PhD)
Motivational incentives play a central role in human decision-making and the pursuit of behavioral and cognitive task goals [1,2]. Moreover, the ability to integrate diverse incentives to modulate goal pursuit is essential for healthy cognitive function. A potential mechanism of motivational influence may be via cognitive control, the set of processes that coordinate and regulate cognition and action based on currently maintained goals [3,4]. However, it is currently unknown whether and how different types of incentives are combined in the brain to modulate cognitive control, and how this putative integrated value signal influences goal-directed behavior. In the current functional magnetic resonance imaging (fMRI) study, we utilized an innovative incentive integration task paradigm that establishes dissociable and additive effects of liquid (e.g., juice, neutral, saltwater) and monetary incentives on cognitive task performance, and applied innovative fMRI analysis approaches to elucidate the neural mechanisms that underlie the interaction between motivational and cognitive control process. First, we applied univariate parcel-based approaches to test whether a priori regions of interest (e.g., ventromedial prefrontal cortex, striatum, dorsal anterior cingulate cortex) represented the integrated value of the ‘bundled incentives’, and whether these regions were also associated with variability in cognitive task performance (Aim 1). Second, we applied representational similarity analysis – an innovative multivariate approach – to test whether and how the combined values from diverse motivational incentives are represented in the similarity of neural patterns in fMRI BOLD activity (Aim 2). Moreover, we aimed to examine whether such multivariate approaches were more sensitive to motivational incentive effects compared to univariate approaches, or alternatively provided complementary information to the univariate results in motivational incentive effects. This is the first study, to our knowledge, that investigates the neural mechanisms underlying whether and how value integration of primary/consummatory and secondary/abstract incentives in a cognitive control context guide goal-directed behavior. Importantly, these results provide critical knowledge into the basic neural mechanisms underlying interactions between motivational incentive integration and cognitive control, which can inform subsequent hypotheses about neuromodulatory influences (e.g., dopamine) in such interactions, as well as inform key predictions about targeted neural mechanisms in age-related changes in motivation-cognition interactions as well as maladaptive motivational processes in psychopathology (e.g., depression, addiction).
Chair and Committee
Todd Braver, Deanna Barch, Ryan Bogdan, Camillo Padoa-Schioppa,
Yee, Debbie, "Neural Mechanisms of Motivational Incentive Integration and Cognitive Control" (2019). Arts & Sciences Electronic Theses and Dissertations. 1969.
Available for download on Wednesday, November 04, 2020