Individual differences in neurophysiological correlates of post-response adaptation: A model-based approach

The cognitive control system continuously monitors actions and adapts to enhance task performance and prevent errors. More pronounced amplitudes of early neurophysiological response monitoring signals, such as error-related negativity (ERN) and correct-related negativity (CRN), have been linked to increased response caution and heightened attention to task-relevant features in subsequent trials. However, it remains unclear whether these population-level effects accurately capture adaptive processes at the individual level. This information is crucial for assessing the generalizability of findings, as effects significant at the population level may be driven by only a small subset of participants. Using Bayesian hierarchical drift diffusion modeling on behavioral and EEG data from four datasets, we found robust population-level associations between ERN amplitude and adaptive behaviors but also identified substantial individual variability. The relationship between ERN amplitude and response caution was highly context-dependent, varying across individuals, datasets, and conditions. In contrast, the association between ERN amplitude and attentional focus was more consistent, though influenced by traits related to negative affect. Our results emphasize the importance of considering individual differences to better understand the neural mechanisms underlying adaptive behavior.