In everyday life, our behaviour is often guided by two interacting forces. On the one hand, we are driven by fast, automatic impulses that push us toward things that feel rewarding and away from things that feel unpleasant. This “autopilot” system helps us react quickly, but it can also lead us to act against our own goals — like reaching for cake when we had planned to eat healthily. On the other hand, we have a more deliberate system that allows us to think ahead, weigh consequences, and make goal-directed choices. Much of human behaviour arises from the interaction between these two systems, which sometimes work together but often come into conflict. This thesis studies how these automatic and goal-directed processes shape our decisions. Using experimental tasks, it shows how cues linked to reward or punishment can influence our actions even when they are irrelevant, and how this effect depends on brain chemistry and cognitive capacity. These findings help explain why people sometimes feel like they are acting on “autopilot,” and why resisting temptation can be so difficult. Understanding this balance between impulse and control has important implications for everyday behaviour, as well as for conditions such as addiction and compulsive habits.
Ping Chen obtained her Master’s degree in Education from South China Normal University in 2019. She then began her PhD within the Motivational & Cognitive Control group led by Roshan Cools, co-supervised by Hanneke den Ouden. Her doctoral research investigated the role of dopamine and working memory in reward motivation and cognitive control. Ping was also actively involved in science communication, contributed blog posts to Donders Wonders and promoted research through the Computational Neuropsychiatry Nijmegen Platform. As part of her PhD, she undertook a 6-month research visit to Ghent University, working with Tom Verguts and Senne Braem, with a focus on computational modelling. Since 2024, she has been working as a Research Fellow with Jennfier Cook at the University of Birmingham.