The time course of task 2 response activation in dual-tasking: Modeling results, interindividual differences, and...

In dual-task experiments, overlapping response characteristics of two successive tasks affect performance not only in Task 2 but also in Task 1. This observation is termed the backward crosstalk effect and is often explained by activated Task 2 response information influencing Task 1 response selection. In the present study, we describe and evaluate three diffusion models that specify Task 2 response activation as either linear, asymptotic, or pulse-like. Formal model comparisons and a parameter recovery suggest that linear Task 2 response activation is most accurate for most individuals. However, we also highlight the potential role of individual differences, as a pulse-like Task 2 response activation function may better describe a subset of individuals. Finally, we provide practical recommendations for researchers on how to fit the backward crosstalk effect in the larger context of dual-tasking. (PsycInfo Database Record (c) 2025 APA, all rights reserved).