Disentangling stimulus and response compatibility as potential sources of backward crosstalk

Jeff Miller,Tobias Rieger

doi:10.3758/s13414-020-02039-6

Abstract

In two experiments (N= 60 each), we investigated the locus of backward crosstalk effects in dual tasking. Specifically, we embedded the typical flanker task within a dual-task paradigm by assigning stimulus-response (S-R) rules to the flankers. In Experiment 1, participants were instructed to first respond to the center letter and only respond to the flanker if the center was a no-go stimulus (i.e., prioritized processing paradigm). Mapping condition was varied between-subjects to be either matched (i.e., same S-R rule for flankers as for center letters), reversed (i.e., opposite S-R rule for flankers), or neutral (i.e., different letters for flankers with separate S-R rules). The results indicated that the backward crosstalk effect was mainly driven by a stimulus-based compatibility, as indicated by a significant S2−R1 compatibility effect in the matched and reversed conditions, with little change in this effect between the matched and reversed conditions. Experiment 2 replicated and extended these findings to a psychological refractory period paradigm. The present findings suggest that in the matched and reversed conditions, there was only one S-R rule active at a time.

Highlights

Background taskRT2 and PE2An ANOVA with the between-subject factor mapping condition was run for RT2
In the neutral mapping condition, there is no S2−R1 compatibility as the flanker letters are always drawn from a different letter set than the center letters—for this condition, we refer to the R2−R1 compatibility
Using an extended psychological refractory period (PRP) approach with three tasks that were less related than the two tasks in our present research, Janczyk et al (2018) argued that backward crosstalk effect” (BCE) are located at the central response selection stage of processing. This idea would be consistent with the present conclusions, because we argue that the combined results of the matched and reversed conditions contradict the idea of a separate stage generating response activation associated with a later task, and the findings in the neutral condition of Experiment 2 seem to contradict pure response selection bottleneck (RSB) accounts with non-overlapping response selection stages of the two tasks

Summary

Introduction

Background taskRT2 and PE2An ANOVA with the between-subject factor mapping condition was run for RT2. Post hoc pairwise comparisons revealed significant differences between all three conditions (ps < .014). Note that it is not possible to examine effects on R2 of the match between R1 and R2 (i.e., forward compatibility) in the PP paradigm, because any trial with an R2 in the PP paradigm necessarily followed a no-go S1. Such effects will be examined in Experiment 2 using the PRP paradigm, . Post-hoc pairwise comparisons revealed a significant effect between the matched condition (9.9%) and the reversed condition (18.1%), p < .001, and between the neutral (12.6%) and the reversed condition, p = .015.

Results

Discussion

Conclusion