Influence of frontal theta oscillation during conflicting Pavlovian bias
by Laura Fürst
Date of Examination:2025-01-29
Date of issue:2025-01-27
Advisor:Prof. Dr. Andrea Antal
Referee:Prof. Dr. Andrea Antal
Referee:PD Dr. Andreas Neef
Files in this item
Name:Fuerst_Laura_eDiss.pdf
Size:5.89Mb
Format:PDF
This file will be freely accessible after 2025-02-26.
Abstract
English
Pavlovian biases influence learning and decision-making by shaping action initiation and suppression but vary among individuals and are not always advantageous. The prefrontal cortex plays a key role in resolving conflicts between competing motivational systems, with midfrontal theta oscillations serving as a marker of prefrontal control. However, the exact mechanisms of this regulation remain unclear. This study used two experimental phases with continuous EEG recordings. In Phase 1, participants learned active and passive choices within probabilistic reward and punishment contexts, separating model-free (Pavlovian bias) and model-based (prefrontal control) systems. Phase 2 introduced a forced-choice task to evaluate Pavlovian biases in learned value. Behavioral results showed the best performance in the Go-to-Win condition and the worst in the NoGo-to-Win condition, with poorer performance on Pavlovian conflicting cards. EEG analysis revealed increased theta power associated with Pavlovian conflict, independent of action and reinforcement demands, and a negative correlation between theta peak frequency and task accuracy. These findings highlight the role of theta oscillations in regulating Pavlovian biases and suggest theta power as a marker for prefrontal control in decision-making. This work provides a foundation for future studies on theta oscillations using non-invasive brain stimulation techniques.
Keywords: EEG; Pavlovian bias; frontal theta