Temporal aspects of two types of backward crosstalk in dual-tasks: An analysis of continuous mouse-tracking data

A common explanation for processing limitations in dual-tasking is the existence of a bottleneck during response selection, meaning that the selection of responses can only occur serially for different tasks. However, a large body of data shows that features of a (secondary) Task 2 can already influence the processing of a (primary) Task 1. Such effects are referred to as backward crosstalk effects (BCEs). In the present study, two types of such BCEs were investigated: the compatibility-based BCE, which depends on the dimensional (often spatial) overlap between task features, and a BCE based on a go/no-go task in Task 2 (no-go BCE). Joining a line of research that suggests different mechanisms for these two types of BCEs, we investigated them using a mouse-tracking setup. Time continuous analyses revealed that the compatibility-based BCE triggered a spatial activation of the Task 2 response early during Task 1 processing, whereas the no-go BCE triggered an inhibitory effect in the case of a no-go Task 2, which spills over to Task 1 execution. This occurred, however, earlier in the time course than expected. The results are discussed with regard to recent models of dual-task processing.