Attentional control adjustments in Eriksen and Stroop task performance can be independent of response conflict

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.

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.

Memory for abstract control states does not decay with increasing retrieval delays

Recent studies have suggested that abstract control states (i.e., internal attentional states independent from concrete stimuli and responses) can be stored in episodic memory and retrieved subsequently. However, the duration of such a control state memory remains unclear. Previous research has found a quick and complete decay for stimulus-response bindings after 2000-5000 ms. Here, we tested a possible decay of control state bindings with retrieval delays of 2000, 3000, or 5000 ms. Five preregistered experiments used a confound-minimized prime-target task to measure the congruency sequence effect (CSE) separately for trials in which a nominally irrelevant context feature changed or repeated across trials. Analyses of the individual experiments did not result in conclusive evidence. A mega-analysis integrating the data of all experiments (Ntotal = 326) replicated evidence for binding and retrieval of control states, in that larger CSEs were found for context repetition trials. Importantly, Bayesian analysis indicated that this effect was not modulated by the length of retrieval delay. While this finding suggests that bindings of abstract control states can be relatively robust, we also discuss possible limitations of the present research.

Proactive control: Endogenous cueing effects in a two-target attentional blink task

This study examined proactive control in a two-target task using an endogenous cueing method. Participants identified two target words (T1 then T2) presented in rapid succession. T1 was presented alone or interleaved with a distractor word. In Experiment 1, informative pre-cues that signalled T1 selection difficulty were randomly intermixed with uninformative pre-cues. The results revealed a cueing effect for both T1 and T2, with better performance for informative cues than for uninformative cues. In Experiment 2, informative and uninformative cues were mixed for one group, and blocked for another group. In the mixed cue group, we again found a T2 cueing effect. In the blocked cue group, a cueing effect was observed for both T1 and T2, with the T2 cueing effect restricted to the shortest T1-T2 SOA. The results demonstrate that pre-cues of attentional conflictcan modulate performance in a two-target task used to measure the attentional blink.

Cognitive reserve counteracts typical neural activity changes related to ageing

Studies have shown that older adults with high Cognitive Reserve (HCR) exhibit better executive functioning than their low CR (LCR) counterparts. However, the neural processes linked to those differences are unclear. This study investigates (1) the neural processes underlying executive functions in older adults with HCR compared to older adults with LCR and (2) how executive control differences between HCR and LCR groups are modulated by increased task difficulty. We recruited 74 participants (37 in each group) with diverse CR levels, as determined by a standardised CR questionnaire. Participants performed two executive control tasks with lower and higher difficulty levels (i.e., Simon and spatial Stroop tasks, respectively) while recording the electroencephalogram. The accuracy on both tasks requiring inhibition of irrelevant information was better in the HCR than the LCR group. Also, in the task with higher difficulty level (i.e., the spatial Stroop task), event-related potential (ERP) latencies associated with inhibition (i.e., frontal N200) and updating of working memory (i.e., P300) were earlier in HCR than LCR. Moreover, the HCR, but not the LCR group, showed larger P300 amplitude in parietal than frontal regions and in the left than right hemisphere, suggesting a posterior to anterior shift of activity and loss of inter-hemispheric asymmetries in LCR participants. These results suggest that high CR counteracts neural activity changes related to ageing. Thus, high levels of CR may be related to maintenance of neural activity patterns typically observed in young adults rather than to deployment of neural compensatory mechanisms.

Role of cognitive control in resolving two types of conflict during spoken word production

A theoretically- and clinically-important issue for understanding word retrieval is how speakers resolve conflict during linguistic tasks. This study investigated two types of conflict resolution: prepotent conflict, when one dominant incorrect response must be suppressed; and underdetermined conflict, when multiple reasonable responses compete. The congruency sequence effect paradigm was used to assess trial-to-trial changes in reaction time and accuracy during word production tasks with either prepotent or underdetermined conflict. Pictures were named faster on trials with low-conflict as compared to high-conflict regardless of conflict type. This effect was modulated by the amount of conflict experienced on the previous trial for both tasks. These results suggest that resolution of underdetermined and prepotent conflict may engage the same general cognitive mechanism. This work expands our understanding of the relationship between cognitive control and word production and can inform clinical approaches for people with anomia.

Performance-contingent reward increases the use of congruent distracting information

In conflict tasks like the Simon task, participants are instructed to respond to a task-relevant target dimension while ignoring additional distracting information. In the Simon task the distracting spatial information can be congruent or incongruent with the task-relevant target information, causing a congruency effect. As seen in the proportion congruency effect and the congruency sequence effect, this congruency effect is larger in mostly congruent blocks and following congruent trials, respectively. Common theories suggest that when the proportion of incongruent trials is high or after an incongruent trial, focus on the task-relevant target information is increased and distracting information is inhibited. In two experiments, we investigated how reward modulates these phenomena. Specifically, performance-contingent reward - but not non-contingent reward - increased the usage of the distracting information in mostly congruent blocks or following congruent trials, while the adaptation to incongruency (i.e., mostly incongruent blocks or preceding incongruent trials) was the same in all conditions. Additional diffusion model analyses found that this effect of performance-contingent reward was captured by the drift rate parameter. These results suggest an increased focus on the target information by incongruent trials independent from reward, while the adaptation to (mostly) congruent trials characterized by increased usage of distracting information can be motivationally boosted. That is, performance-contingent reward increases the use of congruent distracting information beyond a mere relaxation of the increased target-focus following (mostly) congruent trials.

Pre-post intervention exploring cognitive function and relationships with weight loss, intervention adherence and dropout

Objective

To evaluate the association between baseline cognitive function, intervention dropout, adherence and 3-month weight loss (WL) when controlling for confounding demographic variables.

Methods

107 (Mage = 40.9 yrs.), BMI in the overweight and obese range (BMI = 35.6 kg/m²), men (N = 17) and women (N = 90) completed a 3-month WL intervention. Participants attended weekly behavioral sessions, comply with a reduced calorie diet, and complete 100 min of physical activity (PA)/wk. Cognitive function tasks at baseline included Flanker (attention), Stroop (executive control) and working memory, demographics, body weight and cardiovascular fitness were assessed at baseline. Session attendance, adherence to PA and diet were recorded weekly.

Results

Baseline attention was positively correlated with age (p < .05), education (p < .05), attendance (p < .05), diet (p < .05) and PA (p < .05). Baseline executive control (p < .05) and working memory (p < .05) were each associated with % WL. Baseline executive control (p < .01) and working memory (p < .001) were also each associated with education. ANOVA indicated that baseline attention (p < .01) was associated with WL, specifically for comparing those who achieved 5-10% WL (p < .01) and those who achieved greater than 10% WL (p < .01) to those who dropped.

Significance

Results suggest that stronger baseline attention is associated with completion of a 3-mo. WL intervention. Executive control and working memory are associated with amount of WL achieved.

NCT registration

US NIH Clinical Trials, NCT01664715.

Distributional analyses reveal the individual differences in congruency sequence effect

As a sequential modulation of conflict, congruency sequence effect indexes a conflict-induced performance improvement, which is observed as reduced congruency effects for trials after the incongruent trials than for trials after the congruent trials. Although congruency sequence effect has been investigated widely in healthy humans, the studies of distributional characteristics across prototypical congruency tasks are scarce. To investigate this issue, the present study adopts the between-subjects design to carry out three experiments, where subjects were separately informed to perform the Stroop, word Flanker, and letter Flanker tasks. The results showed that congruency sequence effect occurred in the congruent and incongruent trials in the Stroop and word Flanker tasks, respectively, and absented in the letter Flanker task, which is interpreted as the differences in the nature and difficulty of the tasks. The distributional properties of congruency sequence effect did not significantly differ from the Gaussian distribution in the Stroop and word Flanker tasks, but not in the letter Flanker task, suggesting the inter-individual variability of congruency sequence effect depends on the nature of tasks. Importantly, the delta plot analyses showed pronouncedly increased congruency sequence effect over the slowest percentile bines in both the Stroop and word Flanker tasks, verifying the activation suppression hypothesis. Altogether, the present study enriches the literature on the distributional characteristics of congruency sequence effect.

Costs and benefits of audiovisual interactions

A strong temporal correlation promotes integration of concurrent sensory signals, either within a single sensory modality, or from different modalities. Although the benefits of such integration are well known, far less attention has been given to possible costs incurred when concurrent sensory signals are uncorrelated. In two experiments, subjects categorized the rate at which a visual object modulated in size, while they also tried to ignore a concurrent task-irrelevant broadband sound. Overall, the experiments showed that (i) losses in accuracy from mismatched auditory and visual rates were larger than gains from matched rates and (ii) mismatched auditory and visual rates slowed responses more than they were sped up when rates matched. Experiment One showed that audiovisual interaction varied with the difference between the visual modulation rate and the modulation rate of a concurrent auditory stimulus. Experiment Two showed that audiovisual interaction depended upon the strength of the task-irrelevant auditory modulation. Although our stimuli involved abstract, low-dimensional stimuli, not speech, the effects we observed parallel key findings on interference in multi-speaker settings.

Trial-to-trial modulation of task-order switch costs survive long inter-trial intervals

BACKGROUND

Dual-tasking procedures often involve the successive presentation of two different stimuli, requiring participants to execute two tasks in a particular order. Performance in both tasks suffers if the order of the tasks is reversed (i.e., switched) compared to the directly preceding trial. This task-order switch cost is reduced, however, if the preceding trial itself involved a task-order switch compared to a task-order repetition (Strobach in Acta Psychol 217:103328, 2021). Theoretical accounts range from assumptions of top-down implementation of a task-order control set, or passive persistence thereof, to priming based on episodic binding of tasks and temporal positions. Here, we tested these accounts by investigating whether the sequential modulation decays as a function of the inter-trial interval.

METHODS AND RESULTS

Task-order switch costs were reliably reduced after a task-order switch (compared to after a task-order repetition) and this reduction did not decrease over inter-trial intervals ranging from 350 ms to 1,400 ms. Also replicating previous findings, for reaction times the reduction was driven by selective slowing in task-order repeat trials, suggesting increased response caution.

CONCLUSIONS

Our results are consistent with preparatory processes of task-order control or with episodic integration of task-order information but argue against accounts assuming short-lived, decaying task-order sets.

Reward Modulates Unconsciously Triggered Adaptive Control Processes

Adaptive control (e.g., conflict adaptation) refers to dynamic adjustments of cognitive control processes in goal-directed behavior, which can be influenced by incentive rewards. Recently, accumulating evidence has shown that adaptive control processes can operate in the absence of conscious awareness, raising the question as to whether reward can affect unconsciously triggered adaptive control processes. Two experiments were conducted to address the question. In Experiment 1, participants performed a masked flanker-like priming task manipulated with high- and low-value performance-contingent rewards presented at the block level. In this experiment conflict awareness was manipulated by masking the conflict-inducing stimulus, and high- or low-value rewards were presented at the beginning of each block, and participants earned the reward contingent upon their responses in each trial. We observed a great conflict adaptation for high-value rewards in both conscious and unconscious conflict tasks, indicating reward-induced enhancements of consciously and unconsciously triggered adaptive control processes. Crucially, this effect still existed when controlling the stimulus-response repetitions in a rewarded masked Stroop-like priming task in Experiment 2. The results endorse the proposition that reward modulates unconsciously triggered adaptive control to conflict, suggesting that individuals may enable rewarding stimuli to dynamically regulate concurrent control processes based on previous conflict experience, regardless of whether the previous conflict was experienced consciously.

Further Evidence for the Binding and Retrieval of Control-States From the Flanker Task

In response-interference tasks, congruency effects are reduced in trials that follow an incongruent trial. This congruence sequence effect (CSE) has been taken to reflect top-down cognitive control processes that monitor for and intervene in case of conflict. In contrast, episodic-memory accounts explain CSEs with bottom-up retrieval of stimulus-response links. Reconciling these opposing views, an emerging perspective holds that memory stores instances of control - abstract control-states - creating a shortcut for effortful control processes. Support comes from a study that assessed CSEs in a prime-target task. Here, repeating an irrelevant context feature boosted CSEs, possibly by retrieving previously stored control-states. We present a conceptual replication using the Eriksen flanker task because previous research found that CSEs in the flanker task reflect different control mechanisms than CSEs in the prime-target task. We measured CSEs while controlling for stimulus-response memory effects and manipulated contextual information (vertical spatial location) independently from the stimulus information, which introduced the conflict (horizontal spatial location). Results replicate previous findings - CSEs increased for context-repetition compared to context-changes. This study shows that retrieval of control-states is not limited to a specific task or context feature and therefore generalizes the notion that abstract control parameters are stored into trial-specific event files.

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.

Event-related brain potentials reveal strategy selection in younger and older adults

It is well-established that younger adults prioritize information accrued during different stages of stimulus evaluation ("early" versus "late") to optimize performance. The extent to which older adults flexibly adjust their processing strategies, however, is largely unexplored. Twenty-four younger and twenty-four older participants completed a cued flanker task in which one of three cues, indicating the probability that a congruent array would appear (75 %, 50 %, or 25 %), was presented on each trial. Behavioral and ERP (CNV, LRP, N2, and P3b) analyses allowed us to infer cue-driven changes in strategy selection. Results indicate that when both younger and older adults expected an incongruent array, they prioritized late, target information, resulting in a decreased susceptibility to the performance-impairing effect of distractors, extending the conclusions of Gratton et al. (1992) to older adults and supporting the claim that strategic control remains largely intact during healthy aging.

A Gratton-like effect concerning task order in dual-task situations

Performing two tasks simultaneously involves the coordination of their processing. Task coordination is particularly required in dual-task situations with varying order of the component tasks. When task order switches between subsequent trials, task-order coordination leads to order switch costs in comparison to task order repetitions (i.e., worse performance in trials associated with an order switch compared to an order repetition). However, the adaptive characteristics of task-coordination processes and order switch costs are underspecified so far. For example, studies on conflict control have shown that these coordination processes can be modulated in response to changes in task demands. The present study investigated therefore whether task-order coordination processes are modulated by the previous experience of a task-order switch. To investigate order switch costs in a dual-task situation with two sensorimotor tasks with variable task-order, we analyzed performance in current trials with task-order switches and with task-order repetitions following task-order switches and task order repetitions in the preceding trial. The data of four different experimental conditions showed that order switch costs were reduced in trials following task-order switches compared to task-order repetitions; resembling the Gratton effect commonly observed in conflict adaptation paradigms. We discussed the present results in the context of task-order set representations, cognitive control theories, and dual-task models.

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.

Multiple Routes to Control in the Prime-Target Task: Congruence Sequence Effects Emerge Due to Modulation of Irrelevant Prime Activity and Utilization of Temporal Order Information

In interference tasks, the magnitude of the congruency effect is reduced in trials that follow an incongruent trial. This congruence sequence effect (CSE) reflects cognitive control processes, yet accounts disagree when and how control is exerted. Here, we address these questions in the context of the prime-target task. In this task, control can either modulate early prime or late target information. Furthermore, control can utilize information specific to the stimulus (perceptual features) or relational information between stimuli (temporal order). Two experiments (N = 41 | N = 62) were conducted using a prime-target task with arrows (prime) and letters (target). We presented either the prime before the target or the target before the prime. For both trial-type transitions, the CSE was assessed. Regarding the first question, when is control exerted, results showed a larger CSE for prime→target relative to target→prime trials. This suggests that control in the prime-target task modulates prime activity. Regarding the second question, how is control exerted, a combined analysis of both experiments showed a larger CSE for repetition of the same prime and target order across two trials (e.g., previous trial: prime→target; current trial: prime→target) compared to changes (e.g., previous trial: prime→target; current trial: target→prime), suggesting that control in the prime-target task can employ temporal selection.

A role of the lateral prefrontal cortex in the congruency sequence effect revealed by transcranial direct current stimulation

Congruency effect is the increase in response time when relevant and irrelevant cues indicate incongruent rather than congruent responses. The congruency effect is smaller in the trial after an incongruent trial than after a congruent trial: this difference is known as the congruency sequence effect (CSE). Psychophysical and neural studies have suggested that the lateral prefrontal cortex (LPFC) and the medial prefrontal cortex are associated with the CSE. In the present study, we applied anodal and cathodal transcranial direct current stimulation, which is thought to result in excitation and inhibition, respectively, on the LPFC, while human participants were performing a flanker task. We found that the CSE was increased under cathodal stimulation (inhibition) of the LPFC. Moreover, the LPFC stimulation modulated the congruency effect after a congruent trial. Further analyses suggested that the results cannot be explained by any of the currently prevailing hypotheses of the CSE, including the conflict monitoring hypothesis, feature integration hypothesis, and temporal learning account. Based on our findings, we propose that a new distinct mechanism might be involved in the CSE. Specifically, the LPFC might contribute to the CSE by maintaining the attention to the task-relevant information, which is an endogenous goal-oriented function and reduces the carry-over of the task-irrelevant information after a congruent trial.

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.

Self-Monitoring in Speaking: In Defense of a Comprehension-Based Account

Speakers occasionally make speech errors, which may be detected and corrected. According to the comprehension-based account proposed by Levelt, Roelofs, and Meyer (1999) and Roelofs (2004), speakers detect errors by using their speech comprehension system for the monitoring of overt as well as inner speech. According to the production-based account of Nozari, Dell, and Schwartz (2011), speakers may use their comprehension system for external monitoring but error detection in internal monitoring is based on the amount of conflict within the speech production system, assessed by the anterior cingulate cortex (ACC). Here, I address three main arguments of Nozari et al. and Nozari and Novick (2017) against a comprehension-based account of internal monitoring, which concern cross-talk interference between inner and overt speech, a double dissociation between comprehension and self-monitoring ability in patients with aphasia, and a domain-general error-related negativity in the ACC that is allegedly independent of conscious awareness. I argue that none of the arguments are conclusive, and conclude that comprehension-based monitoring remains a viable account of self-monitoring in speaking.

On (Correctly Representing) Comprehension-Based Monitoring in Speaking: Rejoinder to Nozari (2020)

Misunderstanding exists about what constitutes comprehension-based monitoring in speaking and what it empirically implies. Here, I make clear that the use of the speech comprehension system is the defining property of comprehension-based monitoring rather than conscious and deliberate processing, as maintained by Nozari (2020). Therefore, contrary to what Nozari claims, my arguments in Roelofs (2020) are suitable for addressing her criticisms raised against comprehension-based monitoring. Also, I indicate that Nozari does not correctly describe my view in a review of her paper. Finally, I further clarify what comprehension-based monitoring entails empirically, thereby dealing with Nozari's new criticisms and inaccurate descriptions of empirical findings. I conclude that comprehension-based monitoring remains a viable account of self-monitoring in speaking.

The face of control: Corrugator supercilii tracks aversive conflict signals in the service of adaptive cognitive control

Cognitive control is the ability to monitor, evaluate, and adapt behavior in the service of long‐term goals. Recent theories have proposed that the integral negative emotions elicited by conflict are critical for the adaptive adjustment of cognitive control. However, evidence for the negative valence of conflict in cognitive control tasks mainly comes from behavioral studies that interrupted trial sequences, making it difficult to directly test the link between conflict‐induced affect and subsequent increases in cognitive control. In the present study, we therefore use online measures of valence‐sensitive electromyography (EMG) of the facial corrugator (frowning) and zygomaticus (smiling) muscles while measuring the adaptive cognitive control in a Stroop‐like task. In line with the prediction that conflict is aversive, results showed that conflict relative to non‐conflict trials led to increased activity of the corrugator muscles after correct responses, both in a flanker task (Experiment 1) and in a prime‐probe task (Experiment 2). This conflict‐induced corrugator activity effect correlated marginally with conflict‐driven increases in cognitive control in the next trial in the confound‐minimalized task used in Experiment 2. However, in the absence of performance feedback (Experiment 3), no reliable effect of conflict was observed in the facial muscle activity despite robust behavioral conflict adaptation. Taken together, our results show that facial EMG can be used as an indirect index of the temporal dynamics of conflict‐induced aversive signals and/or effortful processes in particular when performance feedback is presented, providing important new insights into the dynamic affective nature of cognitive control.

Cognitive control plays a pivotal role in goal‐directed behavior. Nevertheless, it still remains elusive what mechanisms determine how cognitive control is recruited. Recent theories have proposed that negative emotions elicited by conflict help to adaptively increase the cognitive control. Although there is indeed accumulating evidence for the negative valence of conflict, no study has yet linked this directly to increased adaptive control. Using valence‐sensitive EMG measures, we here show that conflict is associated with increased activation of the corrugator (frowning) muscle and that the size of this effect predicts the size of conflict‐driven control adjustment in the next trial.

Attentional Reorientation and Inhibition Adjustment in a Verbal Stroop Task: A Lifespan Approach to Interference and Sequential Congruency Effect

Several parameters influence the interference effect elicited in a Stroop task, especially contextual information. Contextual effects in the Stroop paradigms are known as the Gratton or Sequential congruency effect (SCE). This research aims at isolating two processes contributing to the SCE in a Stroop paradigm, namely attentional reorientation from the color to the word and vice-versa, as well as inhibition (engagement/disengagement from one trial to the next one). To this end, in Study 1 subprocesses of the SCE were isolated. Specifically, attentional reorientation and inhibition were segregated by submitting young adults to a discrete verbal Stroop task including neutral trials. In Study 2, the same procedure was applied to 124 participants aged from 10 to 80 years old to analyze how interference, SCE, and the aforementioned decomposition of attention and inhibition change across the lifespan. In both studies, the Gratton effect was only partially replicated, while both attentional reorientation and inhibition effects were observed, supporting the idea that these two processes contribute to SCE on top of conflict monitoring and of other processes highlighted in different theories (contingency learning, feature integration, and repetition expectancy). Finally, the classical age-related evolution was replicated in Study 2 on raw interference scores, but no age effect was observed when processing speed was taken into account, nor on the isolated attentional reorientation and inhibition processes, which is in line with the hypothesis of stability of the inhibition processes over age.

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.

It's more than just conflict: The functional role of congruency in the sequential control adaptation

According to the conflict monitoring theory (CMT), one of the most prominent theories of cognitive control, the exertion of cognitive control is triggered by the detection of conflicting response tendencies in the anterior cingulate cortex (ACC). Recent research has challenged this emphasis of response conflicts and has debated whether in addition to shielding after incongruent trials the relaxation after congruent trials also contributes to the sequential adaptation of control. To investigate the functionality of facilitative congruent trials in sequential adaptation of control, we conducted two experiments using a visual (Experiment 1) and an auditory (Experiment 2, preregistered) Simon task with stimuli presented laterally to the left or right (creating response congruent and incongruent trials) or without any particular spatial information (creating neutral trials). Both experiments showed converging results: in the error and reaction time data, the Simon effect was smaller following incongruent trials, larger following congruent trials, and the Simon effect following neutral trials was in-between. Results thus suggest that sequential control adaptations can originate from two processes: Increased shielding in response to incongruent trials and relaxation in response to congruent trials. Argumentations for a functional role of congruent and incongruent trials in the sequential adaptation of control suggest a more general theory of fluency monitoring instead of mere conflict monitoring. In addition, such extensions of the CMT provide theoretical explanations of how control is ever relaxed in response conflict tasks after being enhanced by conflict in the first place. Last but not least, the results may also be taken as a further hint that congruent stimuli may provide a positive affective signal for control relaxation just it has already been shown for incongruent stimuli as aversive signals for the up-regulation of control (shielding).

Parallel word processing in the flanker paradigm has a rightward bias

Reading research is exhibiting growing interest in employing variants of the flanker paradigm to address several questions about reading. The paradigm is particularly suited for investigating parallel word processing, parafoveal-on-foveal influences, and visuospatial attention in a simple but constrained setting. However, this methodological deviation from natural reading warrants careful assessment of the extent to which cognitive processes underlying reading operate similarly in these respective settings. The present study investigated whether readers’ distribution of attention in the flanker paradigm resembles that observed during sentence reading; that is, with a rightward bias. Participants made lexical decisions about foveal target words while we manipulated parafoveal flanking words. In line with prior research, we established a parafoveal-on-foveal repetition effect, and this effect was increased for rightward flankers compared with leftward flankers. In a second experiment, we found that, compared with a no-flanker condition, rightward repetition flankers facilitated target processing, while leftward flankers interfered. Additionally, the repetition effect was larger for rightward than for leftward flankers. From these findings, we infer that attention in the flanker paradigm is indeed biased toward the right, and that the flanker paradigm thus provides an effective analogy to natural reading for investigating the role of visuospatial attention. The enhanced parafoveal-on-foveal effects within the attended region further underline the key role of attention in the spatial integration of orthographic information. Lastly, we conclude that future research employing the flanker paradigm should take the asymmetrical aspect of the attentional deployment into account.

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.

Inhibitory Process of Collaborative Inhibition: Assessment Using an Emotional Stroop Task

This study investigated the inhibitory process of collaborative inhibition. An emotional Stroop task was manipulated three times after a group-recall task across three experiments. The results showed that, when participants performed an emotional Stroop task immediately after a group-recall task (Experiment 1) or between two subsequent individual-recall tasks after a group-recall task (Experiment 3), they were able to discriminate color information relating to studied but nonrecalled emotional stimuli more rapidly in the collaborative-recall condition than in the nominal-recall condition. This indicated that participants experienced a stronger inhibition effect in the former condition. However, when the emotional Stroop task was performed after the final individual-recall task (Experiment 2), there were no differences in discrimination between the conditions. These results suggest that the inhibition effect occurs immediately after the group-recall phase and lasts until the final individual-recall task is completed (4 minutes or longer in Experiment 3). It is therefore possible to discuss retrieval inhibition as an underlying mechanism of collaborative inhibition.

Context Modulates Congruency Effects in Selective Attention to Social Cues

Head and gaze directions are used during social interactions as essential cues to infer where someone attends. When head and gaze are oriented toward opposite directions, we need to extract socially meaningful information despite stimulus conflict. Recently, a cognitive and neural mechanism for filtering-out conflicting stimuli has been identified while performing non-social attention tasks. This mechanism is engaged proactively when conflict is anticipated in a high proportion of trials and reactively when conflict occurs infrequently. Here, we investigated whether a similar mechanism is at play for limiting distraction from conflicting social cues during gaze or head direction discrimination tasks in contexts with different probabilities of conflict. Results showed that, for the gaze direction task only (Experiment 1), inverse efficiency (IE) scores for distractor-absent trials (i.e., faces with averted gaze and centrally oriented head) were larger (indicating worse performance) when these trials were intermixed with congruent/incongruent distractor-present trials (i.e., faces with averted gaze and tilted head in the same/opposite direction) relative to when the same distractor-absent trials were shown in isolation. Moreover, on distractor-present trials, IE scores for congruent (vs. incongruent) head-gaze pairs in blocks with rare conflict were larger than in blocks with frequent conflict, suggesting that adaptation to conflict was more efficient than adaptation to infrequent events. However, when the task required discrimination of head orientation while ignoring gaze direction, performance was not impacted by both block-level and current trial congruency (Experiment 2), unless the cognitive load of the task was increased by adding a concurrent task (Experiment 3). Overall, our study demonstrates that during attention to social cues proactive cognitive control mechanisms are modulated by the expectation of conflicting stimulus information at both the block- and trial-sequence level, and by the type of task and cognitive load. This helps to clarify the inherent differences in the distracting potential of head and gaze cues during speeded social attention tasks.

It's the Other Way Around! Early Modulation of Sensory Distractor Processing Induced by Late Response Conflict

Understanding the neural processes that maintain goal-directed behavior is a major challenge for the study of attentional control. Although much of the previous work on the issue has focused on prefrontal brain areas, little is known about the contribution of sensory brain processes to the regulation of attentional control. The present EEG study examined brain oscillatory activities invoked in the processing of response conflict in a lateralized Eriksen single-flanker task, in which target letters were presented at fixation and single distractor letters were presented either left or right to the targets. Distractors were response compatible, response incompatible, or neutral in relation to the responses associated with the targets. The behavioral results showed that responses to targets in incompatible trials were slower and more error prone than responses in compatible trials. The electrophysiological results revealed an early sensory lateralization effect in (both evoked and induced) theta power (3-6 Hz) that was more pronounced in incompatible than compatible trials. The sensory lateralization effect preceded in time a midfrontal conflict effect that was indexed by an increase of (induced) theta power (6-9 Hz) in incompatible compared with compatible trials. The findings indicate an early modulation of sensory distractor processing induced by response conflict. Theoretical implications of the findings, in particular with respect to the theory of event coding and theories relating to stimulus-response binding [Henson, R. N., Eckstein, D., Waszak, F., Frings, C., & Horner, A. Stimulus-response bindings in priming. Trends in Cognitive Sciences, 18, 376-384, 2014; Hommel, B., Müsseler, J., Aschersleben, G., & Prinz, W. The theory of event coding (TEC): A framework for perception and action planning. Behavioral and Brain Sciences, 24, 849-878, 2001], are discussed.

Is adaptive control in language production mediated by learning?

Recent work using the Picture Word Interference (PWI) paradigm has revealed that language production, similar to non-verbal tasks, shows a robust Congruency Sequence Effect (CSE), defined as a decreased congruency effect following incongruent trials. Although CSE is considered an index of adaptive control, its mechanism is debated. In two experiments, we tested the predictions of a learning model of adaptive control in production, using a task-switching paradigm fully balanced to evaluate CSE on a PWI trial as a function of the congruency of a 2-back PWI trial (within-task CSE), as well as a 1-back trial belonging to a different task (cross-task CSE). The second task was a visuospatial task with congruent and incongruent trials in Experiment 1, and a self-paced reading task with ambiguous and unambiguous sentences in Experiment 2 that imposed a gap between the two PWI trials twice as long of that in Experiment 1. A learning model posits that CSE is the result of changes to the connection weights between task-specific representations and a control center, which leads to two predictions in our paradigm: (a) a robust within-task CSE unaffected by the intervening trial and the gap duration, and (b) an absent or reversed cross-task CSE. These predictions were contrasted with two versions of an activation model of CSE. In accord with the predictions of the learning model, we found robust within-task CSE in PWI in both Experiments with a comparable effect size. Similarly, evidence of within-task CSE was also found in the visuospatial and sentence reading tasks. On the other hand, examination of cross-task CSE from PWI to the other tasks and vice versa revealed either absent or reversed CSE. Collectively, these results support a learning model of adaptive control in language production.

Rule reactivation and capture errors in goal directed behaviour

In everyday life people may act automatically, following “unwanted” lines of action which are triggered by contextual cues and may interfere with current goals. Such occurrences are known as “capture errors” in reference to errors that occur when a more salient behaviour takes place when a similar, but less salient, action was intended. Clinical neuropsychological studies suggest that reactivation of previous rules may play an important role in behavioural interference, but such reactivation has been little studied in normal subjects and simple experimental tasks. In the present study we develop this theme, presenting data on 4 subjects who spontaneously showed capture errors in verbal fluency tasks, and developing a new experimental paradigm specifically designed to elicit such interference in normal subjects. In the new paradigm, 101 normal subjects performed a simple series of working memory tasks, including occasional stimuli whose answer matched both the current and the previous rule. We found that normal controls indeed tend to commit more mistakes after the presentation of a stimulus whose answer is consistent with a current and preceding rule. In this case, however, the errors produced are not necessarily associated with a shift back to the old rule, suggesting that rule reactivation leads to a more general interference effect. We discuss the importance of our data from both theoretical and clinical perspectives.

Blame everyone: Error-related devaluation in Eriksen flanker task

Preferences are determined not only by stimuli themselves but also by the way they are processed in the brain. The efficacy of cognitive processing during previous interactions with stimuli is particularly important. When observers make errors in simple tasks such as visual search, recognition, or categorization, they later dislike the stimuli associated with errors. Here we test whether this error-related devaluation exists in Erisken flanker task and whether it depends on the distribution of attention. We found that both attended stimuli (targets) and ignored ones (distractors) are devaluated after errors on compatible trials but not incompatible ones. The extent of devaluation is similar for targets and distractors, indicating that distribution of attention does not significantly influence the attribution of error-related negative affect. We discuss this finding in light of the possible mechanisms of error-related devaluation.

Control adjustments in speaking: Electrophysiology of the Gratton effect in picture naming

Accumulating evidence suggests that spoken word production requires different amounts of top-down control depending on the prevailing circumstances. For example, during Stroop-like tasks, the interference in response time (RT) is typically larger following congruent trials than following incongruent trials. This effect is called the Gratton effect, and has been taken to reflect top-down control adjustments based on the previous trial type. Such control adjustments have been studied extensively in Stroop and Eriksen flanker tasks (mostly using manual responses), but not in the picture-word interference (PWI) task, which is a workhorse of language production research. In one of the few studies of the Gratton effect in PWI, Van Maanen and Van Rijn (2010) examined the effect in picture naming RTs during dual-task performance. Based on PWI effect differences between dual-task conditions, they argued that the functional locus of the PWI effect differs between post-congruent trials (i.e., locus in perceptual and conceptual encoding) and post-incongruent trials (i.e., locus in word planning). However, the dual-task procedure may have contaminated the results. We therefore performed an electroencephalography (EEG) study on the Gratton effect in a regular PWI task. We observed a PWI effect in the RTs, in the N400 component of the event-related brain potentials, and in the midfrontal theta power, regardless of the previous trial type. Moreover, the RTs, N400, and theta power reflected the Gratton effect. These results provide evidence that the PWI effect arises at the word planning stage following both congruent and incongruent trials, while the amount of top-down control changes depending on the previous trial type.

Phasic valence and arousal do not influence post-conflict adjustments in the Simon task

According to theoretical accounts of cognitive control, conflict between competing responses is monitored and triggers post conflict behavioural adjustments. Some models proposed that conflict is detected as an affective signal. While the conflict monitoring theory assumed that conflict is registered as a negative valence signal, the adaptation by binding model hypothesized that conflict provides a high arousal signal. The present research induced phasic affect in a Simon task with presentations of pleasant and unpleasant pictures that were high or low in arousal. If conflict is registered as an affective signal, the presentation of a corresponding affective signal should potentiate post conflict adjustments. Results did not support the hypothesis, and Bayesian analyses corroborated the conclusion that phasic affects do not influence post conflict behavioural adjustments in the Simon task.

The benefit of expecting no conflict--Stronger influence of self-generated than cue-induced conflict expectations on Stroop performance

The role of expectations in sequential adaptation to cognitive conflict has been debated controversially in prior studies. On the one hand, a sequential congruency effect (SCE) has been reported for trials in which participants expect a repetition of conflict level. On the other hand, conflict level expectations vs. the SCE have been shown to develop differentially across runs of trials with the same conflict level, arguing against the theory that the SCE is purely driven by expectation. The current verbal Stroop experiment addresses this controversy by two means. First, we tested which specific type of expectation (cue-induced expectations vs. self-generated predictions) might affect the SCE. Second, we assessed the impact of expectation on the SCE as well as the development of SCE and expectation with congruency level run length in one design. We observed a dissociation between expectations and SCE, demonstrating that the SCE is not exclusively driven by expectations. At the same time, we found evidence that (self-generated) expectations do have an impact on the SCE. Our data document especially high performance for one specific combination of task events: congruent trial accompanied by congruent prediction and conflict level repetition. Our results are in line with theories attributing conflict adaptation effects to the "adaption to the lack of conflict". We discuss our results in a broader context of theories about conflict monitoring.

Functional characteristics of control adaptation in intermodal sensory processing

The present work investigated functional characteristics of control adjustments in intermodal sensory processing. Subjects performed an interference task that involved simultaneously presented visual and auditory stimuli which were either congruent or incongruent with respect to their response mappings. In two experiments, trial-by-trial sequential congruency effects were analysed for specific conditions that allowed ruling out "non-executive" contributions of stimulus or response priming to the respective RT fluctuations. In Experiment 1, conflict adaptation was observed in an oddball condition in which interference emanates from a task-irrelevant and response-neutral low-frequency stimulus. This finding characterizes intermodal control adjustments to be based - at least partly - on increased sensory selectivity, which is able to improve performance in any kind of interference condition which shares the same or overlapping attentional requirements. In order to further specify this attentional mechanism, Experiment 2 defined analogous conflict adaptation effects in non-interference unimodal trials in which just one of the two stimulus modalities was presented. Conflict adaptation effects in unimodal trials exclusively occurred for unimodal task-switch trials but not for otherwise equivalent task repetition trials, which suggests that the observed conflict-triggered control adjustments mainly consist of increased distractor inhibition (i.e., down-regulation of task-irrelevant information), while attributing a negligible role to target amplification (i.e., enhancement of task-relevant information) in this setup. This behavioral study yields a promising operational basis for subsequent neuroimaging investigations to define brain activations and connectivities which underlie the adaptive control of attentional selection.

Social priming improves cognitive control in elderly adults--evidence from the Simon task

We examined whether social priming of cognitive states affects the inhibitory process in elderly adults, as aging is related to deficits in inhibitory control. Forty-eight elderly adults and 45 young adults were assigned to three groups and performed a cognitive control task (Simon task), which was followed by 3 different manipulations of social priming (i.e., thinking about an 82 year-old person): 1) negative--characterized by poor cognitive abilities, 2) neutral--characterized by acts irrelevant to cognitive abilities, and 3) positive--excellent cognitive abilities. After the manipulation, the Simon task was performed again. Results showed improvement in cognitive control effects in seniors after the positive manipulation, indicated by a significant decrease in the magnitude of the Simon and interference effects, but not after the neutral and negative manipulations. Furthermore, a healthy pattern of sequential effect (Gratton) that was absent before the manipulation in all 3 groups appeared after the positive manipulation. Namely, the Simon effect was only present after congruent but not after incongruent trials for the positive manipulation group. No influence of manipulations was found in young adults. These meaningful results were replicated in a second experiment and suggest a decrease in conflict interference resulting from positive cognitive state priming. Our study provides evidence that an implicit social concept of a positive cognitive condition in old age can affect the control process of the elderly and improve cognitive abilities.

Interactive effects of working memory and trial history on Stroop interference in cognitively healthy aging

Past studies have suggested that Stroop interference increases with age; however the robustness of this effect after controlling for processing speed has been questioned. Both working memory (WM) and the congruency of the immediately preceding trial have also been shown to moderate the magnitude of Stroop interference. Specifically, interference is smaller both for individuals with higher working memory capacity and following an incongruent trial. At present, it is unclear whether and how these 3 variables (age, WM and previous congruency) interact to predict interference effects in the standard Stroop color-naming task. We present analyses of Stroop interference in a large database of Stroop color-naming trials from a lifespan sample of well-screened, cognitively healthy, older adults. Our results indicated age-related increases in interference (after controlling for processing speed) that were exaggerated for individuals with low WM. This relationship between age and WM occurred primarily when the immediately preceding trial was congruent. Following an incongruent trial, interference increased consistently with age, regardless of WM. Taken together, these results support previous accounts of multiple mechanisms underlying control in the Stroop task and provide insight into how each component is jointly affected by age, WM, and trial history.

In Touch With the Simon Effect *The first two authors contributed equally

Cognitive control has been extensively studied using the auditory and visual modalities. In the current study, a tactile version of the Simon task was created in order to test control mechanisms in a modality that was less studied, to provide comparative and new information. A significant Simon effect – reaction time gap between congruent (i.e., stimulus and response in the same relative location) and incongruent (i.e., stimulus and response in opposite locations) stimuli – provided grounds to further examine both general and tactile-specific aspects of cognitive control in three experiments. By implementing a neutral condition and conducting sequential and distributional analysis, the present study: (a) supports two different independent mechanisms of cognitive control – reactive control and proactive control; (b) reveals facilitation and interference within the tactile Simon effect; and (c) proposes modality differences in activation and processing of the spatially driven stimulus-response association.

Even with time, conflict adaptation is not made of expectancies

In conflict tasks, congruency effects are modulated by the sequence of preceding trials. This modulation has been interpreted as a strategic reconfiguration of cognitive control, depending on the amount of conflict encountered on the very last trial, and occurring unconditionally whenever there is time to produce it (Notebaert et al., 2006). Jiménez and Méndez (2013) arranged a 4-choice Stroop task with a response-to-stimulus interval (RSI) of 0 ms, and they found that, under these conditions, congruency effects may become dissociated from the explicit expectancies assessed over analogous, but independent, trials. The present study generalizes this phenomenon to a condition with larger RSI, and it shows that participants’ performance does not rely on expectancies unless the task includes a specific requirement to generate and report on these expectancies. The results are interpreted as providing new insights with respect to the status of conflict adaptation effects.