Congruency sequence effect without feature integration and contingency learning

Generalization of sequence effects from conflict to cueing tasks

Cognitive control has been investigated in attentional conflict tasks for a long time. One representative phenomenon of adaptive cognitive control in these tasks is the congruency sequence effect (CSE), which means that a previous conflict will lead to reduced congruency effects at the current moment, reflecting increased control of attention toward the task at hand. One debating question is whether CSE can generalize between different conditions. Since a similar phenomenon (i.e., validity sequence effect, VSE) has been found in spatial cueing tasks, this study investigated whether the two sequential effects could generalize between each other. A cross-task sequence effect is found from previous flanker trials to current cueing trials when the task sets of the two tasks are either very similar or sufficiently dissimilar, and this C-VSE effect is influenced by the response mode of the experimental design. In addition, the VSE between trial n-2 and trial n is eliminated by the existence of an intermediate flanker trial, but the CSE between trial n-2 and trial n is still significant even with an intermediate cueing trial. Possible explanations of these findings are discussed. The findings suggest a close connection between orienting and executive control processes in attention networks and provide a new perspective and method for investigating the potential mechanisms of cognitive control.

Transfer of cognitive control adjustments within and between speakers

Congruency effects in conflict tasks are typically larger after congruent compared to incongruent trials. This congruency sequence effect (CSE) indicates that top-down adjustments of cognitive control transfer between processing episodes, at least when controlling for bottom-up memory processes by alternating between stimulus-response (S-R) sets in confound-minimised designs. According to the control-retrieval account, cognitive control is bound to task-irrelevant context features (e.g., stimulus position or modality) and retrieved upon subsequent context feature repetitions. A confound-minimised CSE should therefore be larger when context features repeat rather than change between two trials. This study tested this prediction for a more abstract contextual stimulus feature, speaker gender. In two preregistered auditory prime-probe task experiments, participants classified colour words spoken by a female or male voice. Across both experiments, we found confound-minimised CSEs that were not reliably affected by whether the speaker gender repeated or changed. This indicates that speaker transitions have virtually no influence on the transfer of control adjustments in the absence of S-R repetitions. By contrast, when allowing for bottom-up memory processes by repeating the S-R set, CSEs were consistently larger when the speaker gender repeated compared to changed. This suggests that speaker transitions can in principle influence transfer between processing episodes. The discrepancy also held true when considering learning and test episodes separated by an intervening episode. Thus, the present findings call for a refinement of the control-retrieval account to accommodate the role of more abstract contextual stimulus features for the maintenance of memory traces in auditory conflict processing.

A spatial version of the Stroop task for examining proactive and reactive control independently from non-conflict processes

Conflict-induced control refers to humans' ability to regulate attention in the processing of target information (e.g., the color of a word in the color-word Stroop task) based on experience with conflict created by distracting information (e.g., an incongruent color word), and to do so either in a proactive (preparatory) or a reactive (stimulus-driven) fashion. Interest in conflict-induced control has grown recently, as has the awareness that effects attributed to those processes might be affected by conflict-unrelated processes (e.g., the learning of stimulus-response associations). This awareness has resulted in the recommendation to move away from traditional interference paradigms with small stimulus/response sets and towards paradigms with larger sets (at least four targets, distractors, and responses), paradigms that allow better control of non-conflict processes. Using larger sets, however, is not always feasible. Doing so in the Stroop task, for example, would require either multiple arbitrary responses that are difficult for participants to learn (e.g., manual responses to colors) or non-arbitrary responses that can be difficult for researchers to collect (e.g., vocal responses in online experiments). Here, we present a spatial version of the Stroop task that solves many of those problems. In this task, participants respond to one of six directions indicated by an arrow, each requiring a specific, non-arbitrary manual response, while ignoring the location where the arrow is displayed. We illustrate the usefulness of this task by showing the results of two experiments in which evidence for proactive and reactive control was obtained while controlling for the impact of non-conflict processes.

Preparation and persistence of deploying attention to locations or stimulus structures: Evidence from intermixed probe trials

Attention can be directed to the global or local level of a visual stimulus (i.e., Navon figure). Previous studies yielded reliable trial-to-trial level switch costs (i.e., worse performance when responding to the other level than on a previous trial), even though level cueing effects indicated anticipatory deployment of attention to the upcoming target level. To investigate the interplay of attentional preparation and persistence, we applied a probe trial method assumed to ensure a high degree of preparation for the upcoming target level and minimizing stimulus-specific proactive interference. Mirroring previous findings obtained in the domain of spatial attention, we found evidence for anticipatory attentional focusing on global/local target levels but not for persistence of the attentional set adopted on the previous trial. In a second experiment, we prevented preparation for upcoming attentional demands (in both global-local and spatial attention tasks). This resulted in the modulation of performance (in critical probe trials) by the attentional demands of the predecessor trial. Together, our findings demonstrate sensitivity of the probe trial method for attentional persistence and raise the possibility that such persistence can be completely eliminated by sufficiently strong preparation for the attentional demands of the following trial.

The neural dynamics of conflict adaptation induced by conflict observation: Evidence from univariate and multivariate analysis

Conflict adaptation can be expressed as greater performance (shorter response time and lower error rate) after incongruent trials when compared to congruent trials. It has been observed in designs that minimize confounding factors, i.e., feature integration, contingency learning, and temporal learning. Our current study aimed to further elucidate the temporal evolution mechanisms of conflict adaptation. To address this issue, the current study employed a combination of behavioral, univariate, and multivariate analysis (MVPA) methods in a modified color-word Stroop task, where half of the trials required button presses (DO trials), and the other half only required observation (LOOK trials). Both behavioral and the ERP results (N450 and SP) in the LOOK-DO transition trials revealed significant conflict adaptation without feature integration, contingency learning, and temporal learning, providing support for the conflict monitoring theory. Furthermore, during the LOOK trials, significant Stroop effect in the N450 and SP components were observed, indicating that conflict monitoring occurred at the stimulus level and triggered reactive control adjustments. The MVPA results decoded the congruent-incongruent and incongruent-incongruent conditions during the conflict adjustment phase but not during the conflict monitoring phase, emphasizing the unique contribution of conflict adjustment to conflict adaptation. The current research findings provided more compelling supporting evidence for the conflict monitoring theory, while also indicating that future studies should employ the present design to elucidate the specific processes of conflict adaptation.

Normal congruency sequence effects in psychopathology: A behavioral and electrophysiological examination using a confound-minimized design

Clinical studies of adaptive control emphasize the role disruptions in control play in psychopathology. However, many studies used confound-laden designs and examined only one type of psychopathology. Recent studies of event-related potentials (ERPs) suggest that robust congruency sequence effects (CSEs)-a popular index of adaptive control-appear in confound-minimized designs. Thus, the present study sought to determine whether a confound-minimized CSE paradigm could identify adaptive control dysfunction in people with major depressive disorder (MDD), generalized anxiety disorder (GAD), and obsessive-compulsive disorder (OCD). We predicted that participants with MDD and GAD would show smaller ERP CSEs and that participants with OCD would show larger ERP CSEs than healthy controls. Data from 44 people with GAD, 51 people with MDD, 31 people with OCD, and 56 healthy comparison participants revealed normal CSEs as indexed by response times (RTs) and ERPs in the psychopathology groups. Moreover, psychiatric symptoms did not moderate these CSEs. Finally, we observed a strong mean-variance relationship in RT CSEs, such that participants with stronger post-recruitment of control in mean RT scores showed the most consistent post-conflict responses (i.e., the least intraindividual variability). These findings suggest that prior findings from confound-laden tasks indicating altered CSEs in psychopathology stem from processes that are unrelated to adaptive control. Future research should employ experimental designs that isolate these processes to advance our understanding of abnormal CSEs in psychopathology.

Reactive control in suicide ideators and attempters: An examination of the congruency sequence effect in cognitive and emotional Simon tasks

Reactive control is the cognitive ability to adjust thoughts and behaviors when encountering conflict. We investigated how this ability to manage conflict and stress distinguishes suicidal from nonsuicidal individuals. The hypothesis was that suicidal individuals would show poorer reactive control when faced with conflict generated by emotional than neutral stimuli. Hence, individuals with a lifetime history of suicide ideation or attempt and nonsuicidal controls were tested in cognitive and emotional Simon tasks. We examined the congruency sequence effect (CSE) in the Simon tasks as an indication of the efficiency of reactive control in resolving conflict. Whereas controls demonstrated significant CSEs in both tasks, suicide attempters showed a significant CSE in the cognitive task but not in the emotional task. Suicide ideators, on the other hand, displayed marginally significant CSEs in both tasks. Comparing groups with pairwise comparison demonstrated that the difference in CSE was significant only in the emotional task between attempters and controls. Our findings of attempters' inefficiency in adjusting reactive control during the emotional task reflect cognitive inflexibility in coping with conflicting situations during which suicidal individuals become vulnerable to suicide attempts in states of negative emotion.

The role of task-relevant and task-irrelevant information in congruency sequence effects: Applying the diffusion model for conflict tasks

In conflict tasks, such as the Simon, Eriksen flanker, or Stroop task, the congruency effect is often reduced after an incongruent compared to a congruent trial: the congruency sequence effect (CSE). It was suggested that the CSE may reflect increased processing of task-relevant information and/or suppression of task-irrelevant information after experiencing an incongruent relative to a congruent trial. In the present study, we contribute to this discussion by applying the Diffusion Model for Conflict tasks (DMC) framework in the context of CSEs to flanker and Simon tasks. We argue that DMC independently models the task-relevant and task-irrelevant information and thus is a first good candidate for disentangling their unique contributions. As a first approach, we fitted DMC conjointly or separately to previously congruent or incongruent trials, using four empirical flanker and two Simon data sets. For the flanker task, we fitted the classical DMC version. For the Simon task, we fitted a generalized DMC version which allows the task-irrelevant information to undershoot when swinging back to zero. After considering the model fits, we present a second approach, where we implemented a cognitive control mechanism to simulate the influence of increased processing of task-relevant information or increased suppression of task-irrelevant information. Both approaches demonstrate that the suppression of task-irrelevant information is essential to create the typical CSE pattern. Increased processing of task-relevant information, however, could rarely describe the CSE accurately.

A diffusion model for the congruency sequence effect

Two-choice reaction tasks for which stimuli differ on irrelevant and relevant dimensions (e.g., Simon, flanker, and Stroop tasks) show congruency effects. The diffusion model for conflict tasks (DMC) has provided a quantitative account of the mechanisms underlying decisions in such conflict tasks, but it has not been applied to the congruency sequence effect (CSE) for which the congruency on the prior trial influences performance on the current trial. The present study expands analysis of the reaction time (RT) distributions reflected by delta plots to the CSE, and then extends the DMC to simulate the results. With increasing RT: (1) the spatial Simon effect was almost unchanged following congruent trials but initially became smaller and finally reversed following incongruent trials; (2) the arrow-based Simon effects increased following both congruent and incongruent trials, but more so for the former than the latter; (3) the flanker congruency effect varied quadratically following congruent trials but increased linearly following incongruent trials. These results were modeled by the CSE-DMC, extended from the DMC with two additional assumptions: (1) feature integration influences only the controlled processes; (2) following incongruent trials, the automatic process is weakened. The results fit better with the CSE-DMC than with two variants that separately had only one of the two additional assumptions. These findings indicate that the CSEs for different conflict tasks have disparate RT distributions and that these disparities are likely due to the controlled and automatic processes being influenced differently for each trial sequence.

Common and unique neural mechanisms of social and nonsocial conflict resolving and adaptation

Humans often need to deal with various forms of information conflicts that arise when they receive inconsistent information. However, it remains unclear how we resolve them and whether the brain may recruit similar or distinct brain mechanisms to process different domains (e.g. social vs. nonsocial) of conflicts. To address this, we used functional magnetic resonance imaging and scanned 50 healthy participants when they were asked to perform 2 Stroop tasks with different forms of conflicts: social (i.e. face-gender incongruency) and nonsocial (i.e. color-word incongruency) conflicts. Neuroimaging results revealed that the ventral lateral prefrontal cortex was generally activated in processing incongruent versus congruent stimuli regardless of the task type, serving as a common mechanism for conflict resolving across domains. Notably, trial-based and model-based results jointly demonstrated that the dorsal and rostral medial prefrontal cortices were uniquely engaged in processing social incongruent stimuli, suggesting distinct neural substrates of social conflict resolving and adaptation. The findings uncover that the common but unique brain mechanisms are recruited when humans resolve and adapt to social conflicts.

Both task-irrelevant and task-relevant information trigger reactive conflict adaptation in the item-specific proportion-congruent paradigm

Adapting attention flexibly is a fundamental ability of the human control system. In the color-word Stroop task, for example, congruency effects are typically smaller for colors and words that appear mainly in incongruent stimuli (mostly-incongruent items) than for colors and words that appear mainly in congruent stimuli (mostly-congruent items). At least part of this item-specific proportion-congruent (ISPC) effect is due to a process of reactive conflict adaptation that affords higher selectivity (i.e., more efficient selection of task-relevant information) when a specific stimulus is presented that is frequently associated in the experiment with conflicting task-irrelevant information. What is unclear, however, is whether, normally, this stimulus-specific adaptation is triggered by the task-relevant component, the task-irrelevant component, or both components of the stimulus. In two experiments, using modified color-word (Experiment 1) and spatial (Experiment 2) Stroop tasks that allowed task-relevant and task-irrelevant triggering processes to be dissociated, we found that the two processes have approximately equivalent impacts. Because these results were obtained in experiments imposing no limitations on the processes potentially contributing to the ISPC effect, these results challenge claims that the ISPC effect involves conflict-adaptation processes only in special situations. The ISPC effect may involve conflict-adaptation processes in most situations, with both task-relevant and task-irrelevant information triggering such processes.

Rethinking attentional reset: Task sets determine the boundaries of adaptive control

Adaptive control processes that minimise distraction often operate in a context-specific manner. For example, they may minimise distraction from irrelevant conversations during a lecture but not in the hallway afterwards. It remains unclear, however, whether (a) salient perceptual features or (b) task sets based on such features serve as contextual boundaries for adaptive control in standard distractor-interference tasks. To distinguish between these possibilities, we manipulated whether the structure of a standard, visual distractor-interference task allowed (Experiment 1) or did not allow (Experiment 2) participants to associate salient visual features (i.e., colour patches and colour words) with different task sets. We found that changing salient visual features across consecutive trials reduced a popular measure of adaptive control in distractor-interference tasks-the congruency sequence effect (CSE)-only when the task structure allowed participants to associate these visual features with different task sets. These findings extend prior support for the task set hypothesis from somewhat atypical cross-modal tasks to a standard unimodal task. In contrast, they pose a challenge to an alternative "attentional reset" hypothesis, and related views, wherein changing salient perceptual features always results in a contextual boundary for the CSE.

Adaptive control of working memory

The present study investigated mechanisms of adaptive cognitive control in working memory (WM). WM is conceived as a system for short-term maintenance, updating and manipulation of representations required for goal-directed action. Adaptive control refers to the finding of flexible adjustments of control processes based on conflict. For instance, a higher frequency of incongruent stimuli, that is, stimuli evoking conflicting response tendencies, leads to a higher level of cognitive control as reflected by smaller congruency effects (i.e., the difference between congruent and incongruent items). Likewise, conflict on the previous trial leads to a higher level of cognitive control on the current trial. To investigate adaptive control in WM, we used a modified Sternberg paradigm. Participants memorized two differently colored lists of four digits (i.e., 2 5 7 1), in which corresponding positions in both lists contained the same digits (congruent items) or different digits (incongruent items). Participants were required to make a match/mismatch judgement (Experiment 1 and 2) or to recollect the correct digit at a probed position in one of the two lists (Experiment 3). In all experiments, we could replicate both hallmark effects of adaptive control, the proportion congruency effect, and the congruency sequence effect. Our results strongly support the assumption that WM representations can be dynamically adapted based on the amount of conflict, and that adaptive control of WM follows the same principles that have previously been shown for selective attention.

Can the Stroop effect serve as the gold standard of conflict monitoring and control? A conceptual critique

The Stroop effect has been a key to the assay of selective attention since the time of the epoch-making study by J.R. Stroop almost a century ago. However, recent work based on computational modeling and recording of brain activations ignored the primary meaning of the Stroop effect as a measure of selectivity-with the Stroop test losing its raison d'être. Espousing the new framework, numerous studies in the past 20 years conceived performance in the Stroop task in terms of conflict-induced adjustments governed by central control on a trial-to-trial basis. In the face of this tsunami, we try to convince the reader that the Stroop effect cannot serve as a testing ground for conflict-monitoring and control, because these constructs are fundamentally unsuited to serve as a candidate theory of Stroop processes. A range of problems are discussed that singly and collectively pose grave doubts regarding the validity of a control and conflict monitoring account in the Stroop domain. We show how the key notion of conflict is misconstrued in conflict-monitoring models. Due to space limitations and for sake of wider accessibility, our treatment here cannot be technical.

Interactive modulations between congruency sequence effects and validity sequence effects

Sequential modulations have been found in both conflict and spatial orienting tasks. The former is called congruency sequence effects (CSE) and the latter is called validity sequence effects (VSE). Although the two effects have similar phenomenon descriptions, the relationship of the cognitive control mechanisms under the two effects is still unclear. Using a modified attentional network test (ANT), a flanker task and an arrow cueing task are integrated into a single task, which enables the test of the possible interactions between CSE and VSE. Since a confound-minimized design is used, the observed sequence effects cannot be attributed to the feature integration of low-level stimulus features or the contingency learning. It was found that the CSE are only significant when the arrow cue in preceding trial is invalid, and the VSE are only significant when the target letter in preceding trial is congruent with the distractor letters. The findings suggest that the sequential modulations during orienting and executive control of attention networks are highly interacted with each other, and the sequence effects in these networks are possibly controlled by a complex and multifaceted adaptive control mechanism.

Response mode modulates the congruency sequence effect in spatial conflict tasks: evidence from aimed-movement responses

The present study investigated how response mode determines the specificity of control responsible for the congruency sequence effect (CSE), especially when conflict arises from spatial dimensions. Horizontal and vertical Simon tasks were presented in turn, while response mode (Experiment 1) or task-relevant stimulus dimension (Experiment 2) was manipulated. All responses were made by aimed movements to make the relative salience of the horizontal and vertical dimensions equivalent regardless of response mode. The confound-minimized CSEs were significant only when the two tasks shared the same response mode, which did not vary as a function of task-relevant stimulus dimension. This result suggests that response mode determines the scope of control, as it reconfigures the representations of the task-irrelevant spatial dimensions (i.e., the horizontal and vertical dimensions), which is corroborated by distributional analyses. This response mode-specific control was also consistently found for the horizontal and vertical arrow versions of flanker-compatibility tasks in Experiment 3, in which conflict does not directly arise from the response dimension. Furthermore, the current findings revealed that the CSEs were more evident in movement times than in initiation times, which provides new insight on how control inhibits the response activated by a task-irrelevant stimulus dimension, especially at a motor level.

Adjustments of selective attention to response conflict - controlling for perceptual conflict, target-distractor identity, and congruency level sequence pertaining to the congruency sequence effect

The congruency sequence effect (CSE) describes the performance difference of congruent trials (in which target and distractor stimuli are associated with the same response) compared to incongruent trials (in which target and distractor stimuli are associated with different responses) as a function of the preceding congruency level (congruent trials relative to incongruent trials). The CSE is commonly interpreted as a measure of conflict-induced attentional adjustment. Although previous research has made substantial progress aiming at controlling for alternative explanations of the CSE, both task-specific and fundamental confounds have remained. In the current study, we used a temporal flanker task, in which two stimuli (i.e., distractor and target) are presented in rapid succession, and extended previous demonstrations of a CSE in flanker tasks by deconfounding target-distractor congruency from perceptual similarity. Using a four-choice task, we could also control for the reversal of distractor-response priming after incongruent trials (which is only feasible in two-choice tasks). Furthermore, we controlled for all confounds based on the sequence (i.e., repetition versus alternation) of the congruency level – such as feature sequence effects, distractor-response contingency switch costs, or temporal learning – by probing the allocation of attention to the points in time of presentation of the first and the second stimulus of a trial. This was achieved by intermixing trials of a temporal search task. The performance accuracy results in this task were consistent with a stronger attentional bias in favor of the target stimulus’ temporal position after incongruent than after congruent trials.

Cross-task congruency sequence effect without the contribution of multiple expectancy

The confound-minimized cross-task design has been widely used to examine the characteristics of top-down cognitive control underlying the congruency sequence effect (CSE) without feature integration and contingency learning confounds. The present study reanalyzed our previous data obtained with the confound-minimized cross-task design, this time including the preceding congruency repetition type, to examine whether the cross-task CSE is confounded by feature integration from two-back (n-2) trials or multiple expectancies regarding the congruency and the congruency repetition type of the upcoming trial. As a result, the cross-task CSE interacted with the arbitrariness of S-R mapping or response mode regardless of the preceding congruency repetition type, indicating the contribution of top-down control triggered by conflict. Feature integration from n-2 trials, but not multiple expectancies, was found to have a lingering effect on the sequential modulation of the congruency effect between previous and current trials. However, because the influence of feature integration operated in opposite directions depending on the preceding congruency repetition type, the contribution of feature integration to the cross-task CSE can be minimized when the combined datasets of trials following a congruency repetition trial and those following a congruency alternation trial are analyzed. These findings are consistent with recent perspectives on cognitive control, which posit that top-down cognitive control and bottom-up feature integration operate independently to optimize task performance.

The Role of Subjective Experiences in Conflict Tasks: A Review

Cognitive control research is concerned with the question how we install adaptive behaviour in the case of (cognitive) conflict. In this review we focus on the role that awareness of this conflict plays in our ability to exert cognitive control. We will argue that visual conflict is not the only building block of metacognitive experiences of conflict and discuss how they are related to cognitive control. So, a first aim of the current review is to understand how these different metacognitive judgements are created. To do so, we draw some remarkable parallels with research on metacognition in decision making and memory research. Next, we elaborate on the relationship between metacognition and adaptive behaviour, with a specific focus on the role of subjective experiences in the Gratton effect. The grey areas that persist in the current literature are highlighted. In addition to deciphering the mechanisms of metacognitive judgements in cognitive control, this overview also aims to further enlarge our understanding of metacognitive abilities at a more general level.

More change in task repetition, less cost in task switching: Behavioral and event-related potential evidence

Previous studies have shown that the probability of task switching can vary the level of cognitive control and modulate the size of switch costs. However, it is unclear whether switch costs would be affected by a task-repetition context formed by varying the degree of response (and task-relevant stimulus property) change within the task repetition sequences while the probability of task switching remains constant. In the present study, participants were presented with a string of digits (e.g., ②②②). Basing on stimulus color, they were required to indicate either the presented digit, or the number of presented digits. Before task switching, stimulus and response in consecutive task-repeat trials varied more or less frequently. Behavioral results showed that the frequent-change context elicited smaller switch costs than the rare-change context. Event-related potential (ERP) results indicated that: (1) the frequent-change context evoked greater fronto-central N2 amplitudes for both task-repeat and task-switch trials, implying that cognitive control increased due to the variation of stimulus and response associations; (2) for the task switch trials, smaller P300 amplitudes were evoked in the frequent-change context than the rare-change context, reflecting the promoted task-set reconfiguration. These findings suggest that, the more change in stimulus and response during task repetition, the higher the overall level of cognitive control and the higher efficiency of task-switching.

Dynamic Adjustments of Midfrontal Control Signals in Adults and Adolescents

During task performance, our level of cognitive control is dynamically adjusted to task demands as reflected, for example, by the congruency sequence effect (CSE) in conflict tasks. Although brain areas related to cognitive control show protracted maturation across adolescence, previous studies found that adolescents show similar behavioral CSEs to adults. In the present study, we investigated whether there are age-related changes in the neural underpinnings of dynamic control adjustments using electroencephalography. Early adolescents (ages 12-14, N = 30) and young adults (ages 25-27, N = 29) completed a confound-minimized flanker task optimized for the detection of sequential control adjustments. The CSE was observed in midfrontal theta power thought to capture anterior cingulate cortex-mediated monitoring processes but was not modulated significantly by age. Adolescents, however, showed a smaller congruency effect in the power and cross-trial temporal consistency of midfrontal theta oscillations than adults. No age differences were observed in phase-based connectivity between midfrontal and lateral frontal regions in the theta band. These findings provide strong support for the role of midfrontal theta oscillations in conflict monitoring and reactive control and suggest that the cognitive system of early adolescents initially responds less reliably to the occurrence of conflict than that of adults.

Registered Replication Report of Weissman, D. H., Jiang, J., & Egner, T. (2014). Determinants of congruency sequence effects without learning and memory confounds

The congruency sequence effect (CSE) refers to the finding that the effect of cognitive conflict is smaller following conflicting, incongruent trials than after non-conflicting, congruent trials in conflict tasks, such as the Stroop, Simon, and flanker tasks. This is typically interpreted as an upregulation of cognitive control in response to conflict. Weissman, Jiang, & Egner (2014) investigated whether the CSE appears in these three tasks and a further variant where task-irrelevant distractors precede the target (prime-probe task), in the absence of learning and memory confounds in samples collected online. They found significant CSEs only in the prime-probe and Simon tasks, suggesting that the effect is more robust in tasks where the distractor can be translated into a response faster than the target. In this Registered Replication Report we collected data online from samples approx. 2.5 times larger than in the original study for each of the four tasks to investigate whether the task-related differences in the magnitude of the CSE are replicable (Nmin = 115, Nmax = 130). Our findings extend but do not contradict the original results: Bayesian analyses suggested that the CSE was present in all four tasks in RT but only in the Simon task in accuracy. The size of the effect did not differ between tasks, and the size of the congruency effect was not correlated with the size of the CSE across participants. These findings suggest it might be premature to conclude that the difference in the speed of distractor- vs target-related response activation is a determinant of the size of cross-trial modulations of control. The practical implications of our results for online data collection in cognitive control research are also discussed.

The neurocognitive underpinnings of the Simon effect: An integrative review of current research

For as long as half a century the Simon task - in which participants respond to a nonspatial stimulus feature while ignoring its position - has represented a very popular tool to study a variety of cognitive functions, such as attention, cognitive control, and response preparation processes. In particular, the task generates two theoretically interesting effects: the Simon effect proper and the sequential modulations of this effect. In the present study, we review the main theoretical explanations of both kinds of effects and the available neuroscientific studies that investigated the neural underpinnings of the cognitive processes underlying the Simon effect proper and its sequential modulation using electroencephalogram (EEG) and event-related brain potentials (ERP), transcranial magnetic stimulation (TMS), and functional magnetic resonance imaging (fMRI). Then, we relate the neurophysiological findings to the main theoretical accounts and evaluate their validity and empirical plausibility, including general implications related to processing interference and cognitive control. Overall, neurophysiological research supports claims that stimulus location triggers the creation of a spatial code, which activates a spatially compatible response that, in incompatible conditions, interferes with the response based on the task instructions. Integration of stimulus-response features plays a major role in the occurrence of the Simon effect (which is manifested in the selection of the response) and its modulation by sequential congruency effects. Additional neural mechanisms are involved in supporting the correct and inhibiting the incorrect response.

Conflict monitoring and the affective-signaling hypothesis-An integrative review

Conflict-monitoring theory proposes that conflict between incompatible responses is registered by a dedicated monitoring system, and that this conflict signal triggers changes of attentional filters and adapts control processes according to the current task demands. Extending the conflict-monitoring theory, it has been suggested that conflict elicits a negative affective reaction, and that it is this affective signal that is monitored and then triggers control adaptation. This review article summarizes research on a potential signaling function of affect for cognitive control. First, we provide an overview of the conflict-monitoring theory, discuss neurophysiological and behavioral markers of monitoring and control adaptation, and introduce the affective-signaling hypothesis. In a second part, we review relevant studies that address the questions of (i) whether conflict elicits negative affect, (ii) whether negative affect is monitored, and (iii) whether affect modulates control. In sum, the reviewed literature supports the claim that conflict and errors trigger negative affect and provides some support for the claim that affect modulates control. However, studies on the monitoring of negative affect and the influence of phasic affect on control are ambiguous. On the basis of these findings, in a third part, we critically reassess the affective-signaling hypothesis, discuss relevant challenges to this account, and suggest future research strategies.

The congruency sequence effect in a modified prime-probe task indexes response-general control

Adapting flexibly to recent events is essential in everyday life. A robust measure of such adaptive behavior is the congruency sequence effect (CSE) in the prime-probe task, which refers to a smaller congruency effect after incongruent trials than after congruent trials. Prior findings indicate that the CSE in the prime-probe task reflects control processes that modulate response activation after the prime onsets but before the probe appears. They also suggest that similar control processes operate even in a modified prime-probe task wherein the initial prime is a relevant target, rather than merely a distractor. Because adaptive behavior frequently occurs in the absence of irrelevant stimuli, the present study investigates the nature of the control processes that operate in this modified prime-probe task. Specifically, it investigates whether these control processes modulate only the response cued by the prime (response-specific control) or also other responses (response-general control). To make this distinction, we employed a novel variant of the modified prime-probe task wherein primes and probes are mapped to different responses (i.e., effectors), such that only response-general control processes can engender a CSE. Critically, we observed a robust CSE in each of 2 experiments. This outcome supports the response-general control hypothesis. More broadly, it suggests that the control processes underlying the CSE overlap with general mechanisms for adapting to sequential dependencies in the environment. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

EEG Signal Decomposition Evidence for a Role of Perceptual Processes during Conflict-related Behavioral Adjustments in Middle Frontal Regions

Conflict monitoring processes are central to cope with fluctuating environmental demands. However, the efficacy of these processes depends on previous trial history/experience, which is reflected in the "congruency sequence effect" (CSE). Several theoretical accounts have been put forward to explain this effect. Some accounts stress the role of perceptual processes in the emergence of the CSE. As yet, it is elusive how these perceptual processes are implemented on a neural level. We examined this question using a newly developed moving dots flanker task. We combine decomposition methods of EEG data and source localization. We show that perceptual processes modulate the CSE and can be isolated in neurophysiological signals, especially in the N2 ERP time window. However, mechanisms relating perception to action are also coded and modulated in this time window. We show that middle frontal regions (BA 6) are associated with processes dealing with purely perceptual processes. Inferior frontal regions (BA 45) are associated with processes dealing with stimulus-response transition processes. Likely, the neurophysiological modulations reflect unbinding processes at the perceptual level, and stimulus-response translation level needed to respond correctly on the presented (changed) stimulus-response relationships. The data establish a direct relationship between psychological concepts focusing on perceptual processes during conflict monitoring and neurophysiological processes using signal decomposition.

No evidence for the reduction of task competition and attentional adjustment during task-switching practice

Performance in task switching experiments is worse when the current stimulus is associated with different responses in the two tasks (i.e., incongruent condition) than when it is associated with the same response (i.e., congruent condition). This congruency effect reflects some sort of application of the irrelevant task's stimulus-response translation rules. Manipulating the recency and the proportion of congruent and incongruent trials results in a modulation of the congruency effect (i.e., Congruency Sequence Effect, CSE, and Proportion Congruency Effect, PCE, respectively), suggesting attentional adjustment of processing weights. Here, we investigated the impact of task switching practice on the congruency effect and the modulation thereof by (a) re-analyzing the data of a task switching experiment involving six consecutive sessions and (b) conducting a novel four-session experiment in which the proportions of congruent and incongruent trials were manipulated. Although practice appeared to reduce the reaction times overall and the task switch costs (i.e., slower reaction times after task switches than after task repetitions) to an asymptotic level, the congruency effect as well as its modulations remained remarkably constant. These findings thus do not provide evidence that conflict effects between tasks and attentional adjustment are affected by task switching practice.

The effects of induced and trait anxiety on the sequential modulation of emotional conflict

The current study aimed to investigate whether induced anxiety, as well as trait anxiety, would lead to the failure of the regulation of emotional conflict. To measure the regulation of emotional conflict, the congruency sequence effect (CSE), which is a reduced effect of task-irrelevant distractor after incongruent trials compared to congruent trials, was observed while participants performed an emotional conflict task. In Experiment 1, participants performed the task in a safe context and a threatening context where a couple of electric shocks were given randomly on two consecutive days. In Experiment 2, participants performed the same task in either a safe or threatening context to avoid a potential carryover effect of the threat. The CSE observed in the safe context disappeared in the threatening context as well as in participants with high-trait anxiety level even without the threat. The findings imply that induced anxiety causes a failure of cognitive control that engenders the CSE in emotional congruency tasks. Moreover, such failure driven by participants' trait anxiety level might be a potential predisposing factor leading to anxiety disorders. Overall, these results suggest that induced anxiety, as well as trait anxiety, has an adverse impact on the sequential modulation of emotional conflict.

Evidence against conflict monitoring and adaptation: An updated review

One of the most influential ideas in recent decades in the cognitive psychology literature is conflict monitoring theory. According to this account, each time we experience a conflict (e.g., between a colour word and print colour in the Stroop task), attentional control is upregulated to minimize distraction on subsequent trials. Though influential, evidence purported to support this theoretical model (primarily, proportion congruent and congruency sequence effects) has been frequently criticized. Furious debate has centered on whether or not conflict monitoring does or does not occur and, if so, under which conditions. The present article presents an updated review of this debate. In particular, the article considers new research that either (a) seems particularly damaging for the conflict monitoring view or (b) seems to provide support for the theory. The author argues that new findings of the latter sort are still not compelling, several of which have already-demonstrated confounds and others which are plausibly confounded. Further progress has, to a greater extent than not, provided even stronger support for the position that conflict monitoring is merely an illusion. Instead, the net results can be more coherently understood in terms of (relatively) simpler learning/memory biases unrelated to conflict or attention that confound the key paradigms.

Measuring Adaptive Control in Conflict Tasks

The past two decades have witnessed an explosion of interest in the cognitive and neural mechanisms of adaptive control processes that operate in selective attention tasks. This has spawned not only a large empirical literature and several theories but also the recurring identification of potential confounds and corresponding adjustments in task design to create confound-minimized metrics of adaptive control. The resulting complexity of this literature can be difficult to navigate for new researchers entering the field, leading to suboptimal study designs. To remediate this problem, we present here a consensus view among opposing theorists that specifies how researchers can measure four hallmark indices of adaptive control (the congruency sequence effect, and list-wide, context-specific, and item-specific proportion congruency effects) while minimizing easy-to-overlook confounds.

The role of frontopolar cortex in the individual differences in conflict adaptation

It is well known that performance on a trial is flexibly modulated by preceding trial congruency in tasks that require cognitive control, such as the Stroop task, referred to as the conflict adaptation effect (CAE). The CAE indicates that conflict on the preceding trial leads to enhanced cognitive control, leading to more efficient regulation of current conflict. The present study aimed to identify neural mechanisms implicated in individual differences in CAEs. The participants performed a version of the color-word Stroop task during a functional magnetic resonance imaging (fMRI) experiment and were divided into two groups according to the magnitude of behavioral CAE: one exhibiting the CAE only in congruent trials and the other in both congruent and incongruent trials. The imaging results showed different activations in the pre-supplementary motor area for the Stroop effect between groups. Importantly, group differences in activation for the preceding trials were observed in several prefrontal regions including the bilateral frontopolar, dorsolateral prefrontal, and rostro-dorsal cingulate cortices. More interestingly, analyses of the preceding trials suggest that the frontopolar cortex is involved in conflict resolution through higher-order cognitive control strategies that are closely associated with subsequent conflict. The current study provides new evidence of the role of the frontopolar cortex in conflict adaptation.

Multiple expectancies underlie the congruency sequence effect in confound-minimized tasks

The congruency sequence effect (CSE) occurs when the congruency effect observed in tasks such as the Eriksen flanker task is smaller on trials preceded by an incongruent trial relative to trials preceded by a congruent trial. The CSE has been attributed to a range of factors including repetition expectancy, conflict monitoring, feature integration, and contingency learning. To clarify the debate surrounding the CSE and the mechanisms underlying its occurrence, researchers have developed confound-minimized congruency tasks designed to control for feature-integration and contingency-learning effects. A CSE is often observed in confound-minimized tasks, indicating that the effect is driven by repetition expectancy, conflict monitoring, or a combination of the two. Here, we propose and test a variant of the repetition expectancy account that emphasizes how multiple expectations can be formed simultaneously based upon the congruency type (congruent vs. incongruent) and the congruency repetition type (congruency repetition vs. congruency alternation) of the most recent trial. Data from confound-minimized versions of the prime-probe task were found to support this novel account. Data from confound-minimized versions of the Eriksen flanker, Simon, and Stroop tasks indicate that feature-integration confounds often remain in these tasks, potentially undermining the conclusions of previous work. We discuss the implications of these findings for ongoing theoretical debates surrounding the CSE.

Monitoring and control in multitasking

The idea that conflict detection triggers control adjustments has been considered a basic principle of cognitive control. So far, this "conflict-control loop" has mainly been investigated in the context of response conflicts in single tasks. In this theoretical position paper, we explore whether, and how, this principle might be involved in multitasking performance, as well. We argue that several kinds of conflict-control loops can be identified in multitasking at multiple levels (e.g., the response level and the task level), and we provide a selective review of empirical observations. We present examples of conflict monitoring and control adjustments in dual-task and task-switching paradigms, followed by a section on error monitoring and posterror adjustments in multitasking. We conclude by outlining future research questions regarding monitoring and control in multitasking, including the potential roles of affect and associative learning for conflict-control loops in multitasking.

Additive Effects of Item-Specific and Congruency Sequence Effects in the Vocal Stroop Task

There is a growing interest in assessing how cognitive processes fluidly adjust across trials within a task. Dynamic adjustments of control are typically measured using the congruency sequence effect (CSE), which refers to the reduction in interference following an incongruent trial, relative to a congruent trial. However, it is unclear if this effect stems from a general control mechanism or a distinct process tied to cross-trial reengagement of the task set. We examine the relationship of the CSE with another measure of control referred to as the item-specific proportion congruency effect (ISPC), the finding that frequently occurring congruent items exhibit greater interference than items that are often incongruent. If the two effects reflect the same control mechanism, one should find interactive effects of CSE and ISPC. We report results from three experiments utilizing a vocal Stroop task that manipulated these two effects while controlling for variables that are often confounded in the literature. Across three experiments, we observed large CSE and ISPC effects. Importantly, these effects were robustly additive with one another (Bayes Factor for the null approaching 9). This finding indicates that the CSE and ISPC arise from independent mechanisms and suggests the CSE in Stroop may reflect a more general response adjustment process that is not directly tied to trial-by-trial changes in attentional control.

Turning distractors into targets increases the congruency sequence effect

The congruency effect in distractor-interference tasks is typically smaller after incongruent trials than after congruent trials. Current views posit that this congruency sequence effect (CSE) reflects control processes that come into play when an irrelevant distractor cues a different response than a relevant target. However, the CSE is counterintuitively larger in the prime-probe task when the prime is occasionally a second target than when the prime is more frequently a distractor. In the present study, we investigated whether this effect occurs because the appearance of an occasional prime target (a) constitutes a rare, unexpected event that triggers heightened control or (b) allows participants to use the same task set (i.e., stimulus-response mapping) for the prime and probe in each trial. Consistent with the latter hypothesis, we observed this effect in Experiment 1 even when the critical trial types appeared equally often. Further, in Experiment 2, we extended this finding while ruling out perceptual differences between conditions as an alternative account. These findings provide novel support for the task set hypothesis and reveal that the CSE reflects control processes that do more than minimize distraction from irrelevant stimuli.

Determining the scope of control underlying the congruency sequence effect: roles of stimulus-response mapping and response mode

Sequential modulation between two task congruencies has been examined to investigate the nature of the cognitive control mechanism underlying the congruency sequence effect (CSE). Previous results regarding what consecutive tasks must have in common to engender the cross-task CSE are inconsistent. The present study examined the roles of stimulus-response (S-R) mappings and response mode as critical factors in determining the scope of control. Two flanker-compatibility tasks having different stimulus and response sets alternated in turn, and the arbitrariness of S-R mappings alone (Experiment 1) or the arbitrariness of stimulus set and the distinctiveness of response modes (Experiment 2) were manipulated. Experiment 1 showed that non-arbitrary S-R mappings engendered a cross-task CSE even when the response modes were different. However, when S-R mappings were arbitrary in Experiment 2, sequential modulation was evident across two tasks only when their response modes were same, irrespective of the arbitrariness of the stimulus set. These results suggest that the arbitrariness of S-R mappings and response mode are salient task features that reconfigure task representation and consequently determine the scope of the control underlying the CSE.

Target-distractor congruency: sequential effects in a temporal flanker task

The Congruency Sequence Effect (CSE) denotes the common finding that distractor-target Congruency Effects are reduced after incongruent compared to after congruent trials. Although the CSE is widely attributed to attentional adjustment (i.e., increasing or decreasing the bias in attentional weights regarding processing the target or distractor), unequivocal evidence for this assumption is missing. To investigate the CSE and attentional adjustment we used a temporal flanker task and intermixed a "temporal search task", in which a target stimulus occurred randomly at one of two temporal positions, corresponding to the temporal positions of the target and the distractor occurrence in the temporal flanker task. We observed a CSE that could not be explained in terms of feature sequences, distractor-related contingencies, or a strategy of reversed distractor-response priming after incongruent trials. Furthermore, following a temporal search task trial, the Congruency Effect was larger when the search target occurred on the first than on the second temporal position, demonstrating that a reduced attentional bias towards the second temporal position increased interference from a distractor presented on the first temporal position. This supports a crucial assumption of the attentional adjustment account of the CSE. Performance in the temporal search task, however, provided no evidence for attentional adjustment.

"Practice makes perfect?" white matter microstructural characteristic predicts the degree of improvement in within-trial conflict processing across two weeks

Several studies have investigated the trait-like characteristics of conflict processing at different levels. Our study extends these findings by reporting a practice-based improvement in within-trial conflict processing across two sessions. Eighty-three participants performed the same flanker task on two occasions 2 weeks apart. A subset of 37 subjects also underwent diffusion tensor imaging (DTI) scanning the day before the first behavioral task. Despite the trait-like characteristics of conflict processing, within-trial conflict processing in the second behavioral session was significantly shorter than that in the first session, indicating a practice-based improvement in conflict processing. Furthermore, changes in within-trial conflict processing across the two sessions exhibited significant individual differences. Tract-based spatial statistics revealed that the improvement across two sessions was related to the axial diffusivity values in white matter regions, including the body and splenium of the corpus callosum, right superior and posterior corona radiate, and right superior longitudinal fasciculus. Subsequently, lasso regression with leave-one-out cross validation was used to assess the predictive ability of white matter microstructural characteristics in significant regions. The results showed that 61% of individual variability in the improvement in the within-trial conflict processing could be explained by variations in the axial diffusivity values in the four significant regions and the within-trial conflict processing in the first session. These results suggest that axonal morphology in the white tracts connecting conflict-related regions predicts the degree of within-trial conflict processing improvement across two sessions.

How Do Children Deal With Conflict? A Developmental Study of Sequential Conflict Modulation

This study examined age-related differences in sequential conflict modulation (SCM), elicited in three tasks requiring the inhibition of pre-potent responses; a Simon task, an S-R compatibility (SRC) task and a hybrid Choice-reaction/NoGo task. The primary focus was on age-related changes in performance changes following a conflict trial. A secondary aim was to assess whether SCM follows different developmental trajectories depending on the type of conflict elicited by the tasks. The tasks were presented to three different groups of participants with an age range between 7- to 25-years-one group of participants for each task. For each task, the response-to-stimulus interval (RSI) was manipulated (50 vs. 500 ms) across trial blocks to assess time-dependent changes in conflict modulation. The results showed SCM for all three tasks, although the specific patterns differed between tasks and RSIs. Importantly, the magnitude of SCM decreased with advancing age, but this developmental trend did not survive when considering age-group differences in basic response speed. The current results contribute to the emerging evidence suggesting that patterns of SCM are task specific and were interpreted in terms of multiple bottom-up control mechanisms.

Conflict adaptation in patients diagnosed with schizophrenia

Cognitive control impairments may contribute strongly to the overall cognitive deficits observed in patients diagnosed with schizophrenia. In the current study we explore a specific cognitive control function referred to as conflict adaptation. Previous studies on conflict adaptation in schizophrenia showed equivocal results, and, moreover, were plagued by confounded research designs. Here we assessed for the first time conflict adaptation in schizophrenia with a design that avoided the major confounds of feature integration and stimulus-response contingency learning. Sixteen patients diagnosed with schizophrenia and sixteen healthy, matched controls performed a vocal Stroop task to determine the congruency sequence effect - a marker of conflict adaptation. A reliable congruency sequence effect was observed for both healthy controls and patients diagnosed with schizophrenia. These findings indicate that schizophrenia is not necessarily accompanied by impaired conflict adaptation. As schizophrenia has been related to abnormal functioning in core conflict adaptation areas such as anterior cingulate and dorsolateral prefrontal cortex, further research is required to better understand the precise impact of such abnormal brain functioning at the behavioral level.

Resisting distraction and response inhibition trigger similar enhancements of future performance

Resisting distraction and response inhibition are crucial aspects of cognitive control. Interestingly, each of these abilities transiently improves just after it is utilized. Competing views differ, however, as to whether utilizing either of these abilities (e.g., resisting distraction) enhances future performance involving the other ability (e.g., response inhibition). To distinguish between these views, we combined a Stroop-like task that requires resisting distraction with a restraint variant of the stop-signal task that requires response inhibition. We observed similar sequential-trial effects (i.e., performance enhancements) following trials in which participants (a) resisted distraction (i.e., incongruent go trials) and (b) inhibited a response (i.e., congruent stop trials). First, the congruency effect in go trials, which indexes overall distractibility, was smaller after both incongruent go trials and congruent stop trials than it was after congruent go trials. Second, stop failures were less frequent after both incongruent go trials and congruent stop trials than after congruent go trials. A control experiment ruled out the possibility that perceptual conflict or surprise engendered by occasional stop signals triggers sequential-trial effects independent of stopping. Thus, our findings support a novel, integrated view in which resisting distraction and response inhibition trigger similar sequential enhancements of future performance.

Dynamic adjustments of attentional control in healthy aging

In standard attentional control tasks, interference effects are reduced following incongruent trials compared to congruent trials, a phenomenon known as the congruency sequence effect (CSE). Typical explanations of this effect suggest the CSE is due to changes in levels of control across adjacent trials. This interpretation has been questioned by the finding that older adults, individuals with impaired attentional control systems, have been shown to produce larger CSEs in the Stroop task compared with younger adult controls. In 2 experiments, we investigate the generality of this finding by examining how the CSE changes in healthy aging in 3 standard attentional control tasks-Stroop, Simon, and flanker-while controlling for additional confounds that have plagued some of the past literature. In both experiments, older adult participants exhibited a larger CSE in the Stroop task, replicating recent research, but smaller CSEs in both the Simon and flanker paradigms. These results are interpreted as reflecting a pathway priming mechanism in the Stroop task but a control adjustment process in Simon and flanker. Hence, there appears to be different mechanisms underlying the CSE which are engaged based on the type of attentional selection that is required by the task. More generally, these results question the use of the CSE in the Stroop task as a measure of dynamic adjustments in attentional control and highlight the importance of consideration of task-specific control systems underlying the CSE. (PsycINFO Database Record

An Investigation of the Reliability and Self-Regulatory Correlates of Conflict Adaptation

The study of the conflict-adaptation effect, in which encountering information-processing conflict attenuates the disruptive influence of information-processing conflicts encountered subsequently, is a burgeoning area of research. The present study investigated associations among performance measures on a Stroop-trajectory task (measuring Stroop interference and conflict adaptation), on a Wisconsin Card Sorting Task (WCST; measuring cognitive flexibility), and on self-reported measures of self-regulation (including impulsivity and tenacity). We found significant reliability of the conflict-adaptation effects across a two-week period, for response-time and accuracy. Variability in conflict adaptation was not associated significantly with any indicators of performance on the WCST or with most of the self-reported self-regulation measures. There was substantial covariance between Stroop interference for accuracy and conflict adaptation for accuracy. The lack of evidence of covariance across distinct aspects of cognitive control (conflict adaptation, WCST performance, self-reported self-control) may reflect the operation of relatively independent component processes.

Conflict adaptation in schizophrenia: reviewing past and previewing future efforts

INTRODUCTION

Cognitive control impairments have been suggested to be a critical component in the overall cognitive deficits observed in patients diagnosed with schizophrenia. Here, we zoom in on a specific function of cognitive control, conflict adaptation. Abnormal neural activity patterns have been observed for patients diagnosed with schizophrenia in core conflict adaptation areas such as anterior cingulate cortex and prefrontal cortex. On the one hand, this strongly indicates that conflict adaptation is affected. On the other hand, however, outcomes at the behavioural level are needed to create a window into a precise interpretation of this abnormal neural activity.

METHODS

We present a narrative review of behavioural work within the context of conflict adaptation in schizophrenia, focusing on various major conflict adaptation markers: congruency sequence effects, proportion congruency effects, and post-error and post-conflict slowing. The review emphasises both methodological and theoretical aspects that are relevant to the understanding of conflict adaptation in schizophrenia.

RESULTS

Based on the currently available set of behavioural studies on conflict adaptation, no clear-cut answer can be provided as to the precise conflict adaptation processes that are impaired (and to what extent) in schizophrenia populations.

CONCLUSIONS

Future work is needed in state-of-the-art designs in order to reach better insight into the specifics of conflict adaptation impairments associated with schizophrenia.

Feature Integration and Task Switching: Diminished Switch Costs after Controlling for Stimulus, Response, and Cue Repetitions

This report presents data from two versions of the task switching procedure in which the separate influence of stimulus repetitions, response key repetitions, conceptual response repetitions, cue repetitions, task repetitions, and congruency are considered. Experiment 1 used a simple alternating runs procedure with parity judgments of digits and consonant/vowel decisions of letters as the two tasks. Results revealed sizable effects of stimulus and response repetitions, and controlling for these effects reduced the switch cost. Experiment 2 was a cued version of the task switch paradigm with parity and magnitude judgments of digits as the two tasks. Results again revealed large effects of stimulus and response repetitions, in addition to cue repetition effects. Controlling for these effects again reduced the switch cost. Congruency did not interact with our novel “unbiased” measure of switch costs. We discuss how the task switch paradigm might be thought of as a more complex version of the feature integration paradigm and propose an episodic learning account of the effect. We further consider to what extent appeals to higher-order control processes might be unnecessary and propose that controls for feature integration biases should be standard practice in task switching experiments.