The Loci of Stroop Interference and Facilitation Effects With Manual and Vocal Responses

Abstract

Several accounts of the Stroop task assume that the Stroop interference effect has several distinct loci (as opposed to a single response locus). The present study was designed to explore whether this is the case with both manual and vocal responses. To this end, we used an extended form of the Stroop paradigm (Augustinova et al., 2018b) that successfully distinguishes between the contribution of the task vs. semantic vs. response conflict to overall Stroop interference. In line with past findings, the results of Experiment 1 yielded an important response modality effect: the magnitude of Stroop interference was substantially larger when vocal responses were used (as opposed to key presses). Moreover, the present findings show that the response modality effect is specifically due to the fact that Stroop interference observed with vocal responses results from the significant contribution of task, semantic, and response conflicts, whereas only semantic and response conflicts clearly significantly contribute to Stroop interference observed with manual responses (no significant task conflict was observed). This exact pattern was replicated in Experiment 2. Also, and importantly, Experiment 2 also investigated whether and how the response modality effect affects Stroop facilitation. The results showed that the magnitude of Stroop facilitation was also larger when vocal as opposed to manual responses were used. This was due to the fact that semantic and response facilitation contributed to the overall Stroop facilitation observed with vocal responses, but surprisingly, only semantic facilitation contributed with manual responses (no response facilitation was observed). We discuss these results in terms of quantitative rather than qualitative differences in processing between vocal and manual Stroop tasks, within the framework of an integrative multistage account of Stroop interference (Augustinova et al., 2018b).

The effect of high-frequency rTMS of the left dorsolateral prefrontal cortex on the resolution of response, semantic and task conflict in the colour-word Stroop task

“…This finding is somewhat surprising given that previous studies employing similar parameters demonstrate a reduction in RTs on incongruent trials (Li et al 2017 ; Vanderhasslet et al 2006 ). Nevertheless, in contrast to these studies we maximised response conflict in our experiment by employing a pure block design (Hasshim and Parris 2018 ) and a vocal response (Augustinova et al 2019 ). Thus, our data might indicate that facilitation of the left DLPFC leads to a decrease in RTs except when response conflict is high.…”

An fMRI Study of Response and Semantic Conflict in the Stroop Task

“…It is notable that few studies have attempted to decompose Stroop effects into their components. Stroop interference for example has been shown to comprise conflict at a variety of different levels of processing (Augustinova et al, 2019; Ferrand et al, 2019; for a review see Parris, Hasshim, Wadsley, Augustinova, and Ferrand, under review). Doing so not only refines our understanding of the mechanisms of selective attention but also has the potential to elucidate the functions of associated brain regions.…”

Stroop interference is a composite phenomenon: Evidence from distinct developmental trajectories of its components

“…Lété & Fayol, ; Ziegler et al, for this type of endeavor in psycholinguistic children’s studies). These results also (2) invite researchers to preferentially use vocal responses especially when the composite nature of Stroop interference is under scrutiny (see also Augustinova & Ferrand, ; Augustinova, Parris, & Ferrand, for discussions of this issue in adult studies). Another implication of considerable methodological importance is that (3) in order to avoid any conclusions about the (early) developmental trajectory of inhibition (i.e.…”