Robin Vloeberghs (KU Leuven) – Sequential effects in decision-making and decision confidence.
(with Anne Urai)

Our daily life is permeated with decisions. Prominent computational models formalize decision-making as a process of evidence accumulation which is terminated once a boundary is reached. These models assume fixed parameters over the course of a block or a condition, and trial-by-trial changes are considered noise. However, decisions are not isolated events with unchanged dynamics when stimuli are repeatedly presented; decision policies are affected by previous experience in specific ways. Most prominently, decision-making is characterized by choice history biases, a behaviorally observed tendency to repeat (or alternate) previous responses in two-alternative forced-choice tasks. Currently, it remains unclear how such history biases can be understood within an evidence accumulation model. In the current project, I will investigate which mechanism underlies choice history bias, and its modulation by contextual factors such as decision confidence. In addition, I will relate these modeling findings to neural mechanisms using EEG recordings. Collectively, results from this project will form a solid basis for a more dynamic view on decision-making, whereby decisions reach further than the current sensory input.