Location-specific attentional control is also possible in the Simon task

The location-specific proportion congruence effect: Are left/right locations special?

People reactively adjust attentional control based on the history of conflict experiences at different locations resulting in location-specific proportion compatibility (LSPC) effects. Weidler et al. (2022, Journal of Experimental Psychology: Human Perception and Performance, 48[4], 312-330) found that LSPC effects were larger when stimuli were presented on the horizontal axis (i.e., locations to left and right of fixation) compared with the vertical axis (i.e., locations above and below fixation). They proposed and provided initial evidence suggesting left/right locations may represent a special design feature that leads to stronger LSPC effects (i.e., horizontal precedence account). However, their use of horizontally oriented flanker stimuli, which required participants to traverse through the distracting flankers to select the central target selectively in the horizontal axis condition, may have contributed to the horizontal advantage they observed (i.e., gaze path account). The present study tested competing predictions of these two accounts. Experiment 1 used vertically oriented flanker stimuli and compared the findings with Weidler et al. The LSPC effect was larger for vertically oriented stimuli on the vertical axis, and horizontally oriented stimuli on the horizontal axis, supporting the gaze path account. Experiment 2 used flanker stimuli that required participants to traverse through distracting flankers regardless of the axis on which stimuli were presented. The LSPC effect was equivalent between the vertical axis and horizontal axis conditions. These results further supported the gaze path account and suggest that the critical design feature for amplifying LSPC effects is not left/right locations per se, but rather use of stimuli/axis combinations that encourage processing of the distractor dimension.

Motor demands influence conflict processing in a mouse-tracking Simon task

Previous studies have shown incorrect motor activation when making perceptual decisions under conflict, but the potential involvement of motor processes in conflict resolution is still unclear. The present study tested whether the effects of distracting information may be reduced when anticipated motor processing demands increase. Specifically, across two mouse-tracking Simon experiments, we manipulated blockwise motor demands (high vs. low) by requiring participants to move a mouse cursor to either large versus small (Experiment 1) or near versus far (Experiment 2) response boxes presented on the screen. We reasoned that participants would increase action control in blocks with high versus low motor demands and that this would reduce the distracting effect of location-based activation. The results support this hypothesis: Simon effects were reduced under high versus low motor demands and this modulation held even when controlling for time-varying fluctuations in distractor-based activation via distributional analyses (i.e., delta plots). Thus, the present findings indicate that anticipation of different motor costs can influence conflict processing. We propose that the competition between distractor-based and target-based activation is biased at premotor and/or motor stages in anticipation of motor demands, but also discuss alternative implementations of action control.

The dominance of item learning in the location-specific proportion congruence paradigm

Prior research has shown that various cues are exploited to reactively adjust attention, and such adjustments depend on learning associations between cues and proportion congruence. This raises the intriguing question of what will be learned when more than one cue is available, a question that has implications for understanding which cue(s) will dominate in guiding reactive adjustments. Evidence from a picture-word Stroop task demonstrated that item learning dominated over location learning in a location-specific proportion congruence (LSPC) paradigm, a pattern that may explain the difficulty researchers have faced in replicating and reproducing the LSPC effect. One goal was to reproduce this pattern using a non-overlapping two-item set design that more closely matched prior studies, and another goal was to examine generalisability of the pattern to two other tasks. Using a prime-probe, colour-word Stroop task (Experiment 1), and a flanker task (Experiment 2), we again found clear dominance of item learning. In Experiment 3, we attempted to disrupt item learning and promote location learning by using a counting procedure that directed participants' attention to location. Once again, we found the same pattern of item dominance. In addition, in none of the experiments did we find evidence for conjunctive (location-item) learning. Collectively, the findings suggest item learning is neither design- or task-specific; rather, it is robust, reliable, and not easily disrupted. Discussion centres on factors dictating dominance of item- over location-based adjustments and implications for the broader literature on LSPC effects.

Beyond mean reaction times: Combining distributional analyses with processing stage manipulations in the Simon task

We combined analyses of reaction time (RT) distributions with experimental manipulations of different processing stages (perception, decision, motor execution) in a Simon task to investigate which changes in Simon effects could be explained entirely by fading irrelevant response activation. Consistent with fading activation accounts, the Simon effect on mean RT was usually smaller for conditions with slower responses (Expts. 1-3 but not Expt. 4), and delta plot analyses revealed that it was always smaller for the slower responses within each condition. Critically, however, these analyses also revealed that some experimental manipulations produced upward or downward shifts in the RT delta plots, thus altering the Simon effect on mean RT in ways that could not be explained by fading activation. The results demonstrate the power of combining RT distributional analyses with experimental manipulations to reveal mechanisms contributing to the Simon effect that would not be revealed using only mean RT. We consider alternatives to fading activation accounts of decreasing delta plots and discuss the contribution of different cognitive stages in modulating Simon effects.

Context affects implicit learning of spatial bias depending on task relevance

Recent studies on the probability cueing effect have shown that a spatial bias emerges toward a location where a target frequently appears. In the present study, we explored whether such spatial bias can be flexibly shifted when the target-frequent location changes depending on the given context. In four consecutive experiments, participants performed a visual search task within two distinct contexts that predicted the visual quadrant that was more likely to contain a target. We found that spatial attention was equally biased toward two target-frequent quadrants, regardless of context (context-independent spatial bias), when the context information was not mandatory for accurate visual search. Conversely, when the context became critical for the visual search task, the spatial bias shifted significantly more to the target-frequent quadrant predicted by the given context (context-specific spatial bias). These results show that the task relevance of context determines whether probabilistic knowledge can be learned flexibly in a context-specific manner.

The transfer of location-based control requires location-based conflict

It is well supported that stimulus-driven control of attention varies depending on the degree of conflict previously encountered in a given location. Previous research has further shown that control settings established in conflict-biased locations can transfer to nearby unbiased items. However, these spatial transfer effects have only been shown using incompatible flanking arrows (i.e., stimuli that trigger spatial information) to elicit conflict in a flanker task. Here we examine the generalizability of transfer of control by examining if it can occur across a range of tasks. We employ a classic Stroop task (Experiment 1), a spatially segregated Stroop task (Experiment 2), and a spatial Stroop task (Experiment 3). Location-specific proportion compatibility effects were observed in all variations of the Stroop task tested; however, transfer to unbiased items occurred only in the spatial Stroop task in Experiment 3. This suggests that the transfer of cognitive control settings within spatial categories may occur only in tasks where the source of conflict is spatial, as arises in tasks with arrow and direction word stimuli.

Cortical and subcortical contributions to context-control learning

"Cognitive control" describes our ability to strategically bias information processing in line with internal goals. Traditionally, research has focused on delineating the sources of top-down biasing, implicating the lateral prefrontal cortex. The past two decades, however, have seen increasing interest in the regulation of control, that is, how learning processes guide the context-sensitive application of top-down biasing. Here, we review and synthesize recent research into the cognitive and neural mechanisms of this type of "context-control learning". We first discuss a fast-growing cognitive psychology literature documenting how specific cognitive control states can become associated with, and subsequently triggered by, contextual cues. We then review neuroimaging studies that speak to the neural substrates of contextual adjustments in control, with a particular focus on recent work that explicitly modeled context-control learning processes. We conclude that these studies suggest an important subcortical extension of the traditional frontal control network, as they indicate a key role for the caudate nucleus in forming associations between contextual cues and appropriate control settings.