Effects of acoustic warning signal intensity in the control of visuospatial interference

Previous studies have reported increased interference when a task-irrelevant acoustic warning signal preceded the target presentation in cognitive tasks. However, the alerting-congruence interaction was mostly observed for tasks measuring Flanker and Simon interferences but not for Stroop conflict. These findings led to the assumption that warning signals widen the attentional focus and facilitate the processing of irrelevant spatial characteristics. However, it is not clear whether these effects are because of the temporal information provided by the warning signal or because of their alerting effects. Based on these findings, and on the open question about the nature of the warning signal intervention on visuospatial interferences, we decided to test the impact of the warning signal on the processing of irrelevant spatial features, by using a procedure suitable for measuring both Simon and spatial Stroop interferences. We also manipulated the intensity of the warning signal to study the effect of the task-irrelevant characteristics of warning signals in visuospatial interferences. For the Simon conflict, results demonstrated an increased interference provoked by the presence (Experiment 1) and intensity (Experiment 2) of warning signals. In contrast, neither the presence nor the intensity of warning signals affected the spatial Stroop interference. Overall, these findings suggest that the impact of warning signals primarily depends on the processing of irrelevant spatial attributes and on the type of conflict (e.g., spatial stimulus-response interference in Simon vs. stimulus-stimulus interference in spatial Stroop). In general, acoustic warning signals facilitate the automatic response activation, but their modulatory effect depends on the task setting involved.

Language dominance predicts cognate effects and inhibitory control in young adult bilinguals

Determining bilingual status has been complicated by varying interpretations of what it means to be bilingual and how to quantify bilingual experience. We examined multiple indices of language dominance (self-reported proficiency, self-reported exposure, expressive language knowledge, receptive language knowledge, and a hybrid), and whether these profiles related to performance on linguistic and cognitive tasks. Participants were administered receptive and expressive vocabulary tasks in English and Spanish, and a nonlinguistic spatial Stroop task. Analyses revealed a relation between dominance profiles and cognate and nonlinguistic Stroop effects, with somewhat different patterns emerging across measures of language dominance and variable type (continuous, categorical). Only a hybrid definition of language dominance accounted for cognate effects in the dominant language, as well as nonlinguistic spatial Stroop effects. Findings suggest that nuanced effects, such as cross-linguistic cognate effects in a dominant language and cognitive control abilities, may be particularly sensitive to operational definitions of language status.

Bilinguals as “experts”? Comparing performance of mono- to bilingual individuals via a mousetracking paradigm

The question of whether bilingualism conveys a broader advantage in executive functions has recently been controversially discussed, with the empirical findings presenting a complex pattern of positive and null results. Here we present results from three standard tasks measuring executive functions (Flanker; Simon; Spatial Stroop) in which we compared performance of English monolingual to Chinese–English bilingual young adults. Participants provided responses via movement of a computer mouse rather than the conventional key presses, which provides a rich signal of the unfolding response dynamics. Clear differences between bi- and monolinguals emerged, with the former providing more ‘efficient’ responses than the latter. Results are discussed regarding the extent to which these results can be characterised as a genuine “bilingual advantage”.