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Human adaptive behavior requires continually learning and performing a wide variety of tasks, often with very little practice. To accomplish this, it is crucial to separate neural representations of different tasks in order to avoid interference. At the same time, sharing neural representations supports generalization and allows faster learning. Therefore, a crucial challenge is to find an optimal balance between shared versus separated representations. Typically, models of human cognition employ top-down modulatory signals to separate task representations, but there exist surprisingly little systematic computational investigations of how such modulation is best implemented. We identify and systematically evaluate two crucial features of modulatory signals. First, top-down input can be processed in an additive or multiplicative manner. Second, the modulatory signals can be adaptive (learned) or non-adaptive (random). We cross these two features, resulting in four modulation networks which are tested on a variety of input datasets and tasks with different degrees of stimulus-action mapping overlap. The multiplicative adaptive modulation network outperforms all other networks in terms of accuracy. Moreover, this network develops hidden units that optimally share representations between tasks. Specifically, different than the binary approach of currently popular latent state models, it exploits partial overlap between tasks. [ABSTRACT FROM AUTHOR]

Previous studies have suggested that people are sensitive to anticipated cognitive processing demands when deciding which task to perform, but the influence of perceptual processing demands on voluntary task choice is still unclear. The present study tested whether voluntary task choice behavior may be influenced by unpredictable task-specific perceptual processing demands. Across four experiments using different voluntary task choice procedures, we randomly varied the perceptual discriminability of stimuli (easy vs. hard color discrimination) for one of the two tasks. We reasoned that people could only reactively adjust their task choice behavior to the unpredictable discriminability manipulation if they engaged in some perceptual processing before a task goal becomes sufficiently activated to select the task for further processing. The results confirmed this hypothesis: Task performance data demonstrated the presence of perceptual (discriminability effects) and cognitive (switch costs) processing demands. Participants' choice behavior was affected by both types of processing demands (as reflected in a task repetition bias and a bias to select the color task with easy compared to hard discriminations). Thus, the present findings indicate that both perceptual and cognitive processing demands influence voluntary task choice behavior. We propose that higher-level goal activations interact at least partially with early perceptual processes to influence task choice behavior, suggesting a locus of voluntary choices during or after the perceptual stage within the information-processing stream. [ABSTRACT FROM AUTHOR]

Many cognitive tasks have what we refer to as a placekeeping requirement: steps or subtasks must be performed in a linear or other systematic fashion, without repetitions or omissions that would compromise performance. Here we asked whether the cognitive control mechanisms that meet this requirement are specific to individual tasks or general enough to be shared across tasks. Participants (N = 289) performed two tasks (Letterwheel and UNRAVEL) that share a sequential structure but are otherwise distinct. Placekeeping measures correlated significantly across tasks after controlling for construct-irrelevant variance, evidence that individual differences in placekeeping ability correlated across tasks rather than varying independently. Furthermore, an empirical pattern in the form of a crossover interaction in placekeeping error gradients was evident for both tasks, evidence that placekeeping in the two tasks is supported by similar cognitive mechanisms. The results suggest that placekeeping ability is a task-independent cognitive control construct and that placekeeping measures could help predict performance in a range of workplace and everyday tasks. [ABSTRACT FROM AUTHOR]

The distinction between task-switching (T-switch) and response-rule switching (RR-switch) has been reported in previous studies. However, it is unclear whether the neural correlates of proactive and reactive control differ between T-switch and RR-switch. In this study, a modified cue-target task was adopted. When the cue in the current trial differed from that in the preceding trial in shape (or color), the participants had to perform a T-switch (or RR-switch). Otherwise, they performed the same task following the same response rule. The behavioral results showed that the switch cost was greater for the RR-switch than for the T-switch. The event-related potential results indicated that (1) for cues, the switch-positivity in the late positive component (LPC) (500–800 ms) was more enhanced for the RR-switch than for the T-switch over the central to parietal regions, reflecting increased proactive control for the RR-switch compared with the T-switch; (2) for targets, the P3 amplitude was more attenuated in the RR-switch than the T-switch over the central and parietal regions, reflecting increased reactive control for the RR-switch; and (3) under the T-switch, the switch-positivity in the cue-LPC was negatively correlated with accuracy cost, while under the RR-switch, the switch negativity in the target-P3 was positively correlated with the reaction time cost. These findings suggest that similar proactive and reactive control are recruited in the T-switch and RR-switch, whereas cognitive control efforts clearly differ between them, perhaps due to different sub-processes. • Task switching (T-switch) and response rule switching (RR-switch) are compared. • Switch cost is greater in RR-switch than in T-switch. • Cue-LPC was larger in RR-switch than for T-switch. • Target-P3 was decreased in RR-switch than in T-switch. • Cognitive control differs between T-switch and RR-switch. [ABSTRACT FROM AUTHOR]

Task switching refers to the effortful mental process of shifting attention between different tasks. While it is well-established that task switching usually comes with an objective performance cost, recent studies have shown that people also subjectively evaluate task switching as negative. An open question is whether this affective evaluation of task switching is also related to actual decision making. In this pre-registered study, we therefore examined whether individual differences in the negative evaluation of task switch cues are related to less voluntary task switching. To this end, participants first performed a cued task switching paradigm where abstract cues signaled task transitions (repetition or alternation). In a second phase, these transition cues were used as prime stimuli in an affective priming procedure to assess participants' affective evaluation of task switching. In a third phase, participants were allowed to freely choose whether to switch or repeat tasks. We found that a more negative evaluation of task switching cues was related to lower switch rates in the voluntary task switching phase. This finding supports neuroeconomic theories of value-based decision making which suggest that people use their subjective value of control to decide whether to engage in (different) tasks. [ABSTRACT FROM AUTHOR]

Cognitive control is applied in situations that require overriding a habitual and automatic response. The conflict monitoring hypothesis and the Expected Value of Control (EVC) theory as its extension posit a control system responsible for detecting conflicting occasions and adapting to them dynamically within a task. Here we evaluate this prediction in two versions of one of the most popular tasks in cognitive control, namely the Stroop task. We hypothesized that nearby-items interference combines with task interference in the multi-item version effectively turning it into a multi-task that may challenge cognitive control. Adopting an alternative methodology tracking within-task performance, we compared the classical multi-item version of the Stroop task and its single-item counterpart in adults and children. The results revealed a within-task performance decline only in the multi-item version of the task, in both incongruent and neutral conditions, modulated by the presumed maturity of the control system. These findings suggest capacity constraints in control implementation and allocation under conditions requiring parallel execution of multiple cognitive tasks. Task complexity and demands seem to modulate effects on performance. We discuss implications for cognitive control as well as substantial concerns regarding the calculation and use of indices of interference based on the commonly used multi-item version of the Stroop task. [ABSTRACT FROM AUTHOR]

Recent research suggests that motivation improves cognitive functions but the particular mechanisms and precise behavioural conditions involved in such improvement still remain unknown. Particularly, it is unclear when in time and in which conditions these mechanisms are engaged. In the present study, we aimed to look at the neural markers of cognitive control strategies in different motivational conditions (motivation vs neutral) with different levels of difficulty (high vs low). Twenty-five adults completed a newly designed task in the four conditions above. Three ERP components were analysed: the CNV, LRP and P3b. We found that a motivational situation triggers the use of a proactive strategy when low cognitive control is required. A reactive strategy was used in a non-motivational situation and for difficult trials. Our study is also the first to provide evidence that the difference between proactive and reactive strategies occurs after the first stimulus (cue) is processed. [ABSTRACT FROM AUTHOR]

People segregate continuously unfolding experiences into discrete events in memory. This process, known as event segmentation, results in better memory for the temporal order of experiences within an event and expands subjective temporal distance for items encoded across event boundaries. Previous research has suggested that the creation of event boundaries is driven by (typically unpredicted) changes in external stimulation, though many prior studies have confounded a change in bottom-up input with a concurrent change in task goal. This raises the question of whether event segmentation can be triggered by the endogenous cognitive control processes involved in switching task sets, independent of changes in bottom-up stimulation. We investigated this question by embedding task set changes during encoding of a series of trial-unique images, and comparing subsequent temporal order and distance memory for item pairs encoded across a change in task set with item pairs encoded within the same task set. Across five experiments, we demonstrate that both cued and voluntary task set changes are sufficient to create event boundaries, while ruling out potential confounding effects of shifts in stimulus set, response set, task cues, and task difficulty. Thus, internal control processes are a key determinant of segmenting episodic memories, and task set updating can trigger event segmentation independent of any externally induced, perceptual or task-based prediction error. [ABSTRACT FROM AUTHOR]

Our actions cause manifold environmental changes. Monitoring these action effects serves at least two vital functions: While the validation of currently relevant effects assesses goal-achievement, screening for currently irrelevant effects accumulates knowledge about potential action-effect relationships. However, monitoring the perceptual consequences of our actions presumably impairs performance in concurrent tasks. Here, we investigated how effect relevance modulates monitoring costs by manipulating instructions in three dual-task experiments. We found performance decreases not only after validation of goal-relevant action effects but to a smaller extent also after screening of goal-irrelevant action effects. These results suggest that effect monitoring is a rather fundamental limitation of dual tasking. [ABSTRACT FROM AUTHOR]

Previous studies have investigated sequence effect on task switching and found that increased cognitive control in preceding trials would transfer to the current trial. However, it remains unclear whether response variations during task repetition can enhance cognitive control and promote task switching. In the present study, we designed two sequence contexts, the response-change (r-change) and response-repeat (r-repeat) contexts, by adopting a classical task-switching paradigm in which participants were asked to make an odd-even or large-small judgment of the presented digit. The only difference between the two sequence contexts was whether responses varied frequently during task repetition. Behavioral results showed that the r-change context induced smaller switch costs and higher accuracy for task switching than the r-repeat context. Event-related potential (ERP) results revealed (1) the effect of context on N2 amplitudes, with greater N2 in the r-change context than the r-repeat context at frontal-central regions; (2) the interaction between context and transition type during the stimulus-locked P3 component, with a marked context effect for the task-switch trials; (3) non-significant context effect on task switching during the response-locked P3 component. These findings suggest that response variations during a sequence of task-repeat trials can trigger the increase in cognitive control that promotes the efficiency of followed task switching. • Smaller switch costs and higher accuracy for task switching in r-change context than in r-repeat context. • Greater frontal-central N2 in r-change context. • Larger stimulus-locked P3 for task-switch trials in r-change context. • Non-significant context effect on task switching during the response-locked P3 component. • Response variations during task repetition can promote the efficiency of followed task switching. [ABSTRACT FROM AUTHOR]

In humans, voluntary task switching is susceptible to bottom-up influences like a switch of the target stimulus identity (Mayr & Bell, 2006). A recent study with ants (Czaczkes, Koch, Fröber, & Dreisbach, 2018) has shown that even irrelevant cue changes increase switching behavior, but only if they are presented within a high-reward context. To investigate whether a reward context would also increase switching behavior in response to meaningless cue changes in humans, we conducted two voluntary task switching experiments. On each trial, participants chose between two tasks preceded by one of two different color cues. Reward prospect was manipulated between blocks (Experiment 1: no vs. high reward; Experiment 2: low vs. high reward). In both experiments, the cue change did not modulate the voluntary switch rate. However, the voluntary switch rate was significantly lower in high-reward blocks as compared to no-reward or low-reward blocks. This suggests that bottom-up influences on deliberate task switching in humans are limited to task-relevant information. Moreover, the finding of a decreased voluntary switch rate within a high-reward context further supports the claim that unchanged high reward prospect promotes cognitive stability. • Voluntary task switching is susceptible to relevant bottom-up influences like a switch of stimulus or reward prospect. • Here, we investigated whether a reward context would increase switching behavior in response to irrelevant cue changes. • Irrelevant cues did not impact voluntary switching, thus pose a limit to bottom-up influences on voluntary decisions. • In contrast, voluntary switching was rarer in high-reward blocks as compared to no-reward or low-reward blocks. • Hence, unchanged high reward prospect promotes cognitive stability, even for this more long-term manipulation of reward. [ABSTRACT FROM AUTHOR]

• We examined bidialectal benefits in 40 older monolingual and bidialectal adults. • Advantages extend beyond bilingualism to bidialectalism in some Stroop tests. • Bidialectal advantages emerge in Stroop color-word and Stroop day-night tasks. • Bidialectal advantages emerge in tasks resting heavily on inhibitory control. • Bidialectal advantages emerge in tasks with a high or mid level of difficulty. The effect of bidialectalism on older bidialectal adults' performance on cognitive tasks has received little attention in aging studies. The current research aimed to investigate older monolingual and bidialectal adults' performance on nonverbal and verbal cognitive tasks, including Simon, Stroop, flanker, and spatial n-back tasks. Bidialectalism and task effects were examined via a comparison of the monolinguals' and bidialectals' response latencies. Two experiments were conducted, which consisted of four nonverbal tasks (Experiment 1) and four verbal tasks (Experiment 2), respectively. The participants were 20 older Mandarin monolingual adults and 20 older Minnan-Mandarin/Hakka-Mandarin bidialectal adults from Taiwan. The results indicated that the bidialectals performed better than the monolinguals on the nonverbal and verbal Stroop color-word tasks and the verbal Stroop day-night task. The nonverbal tasks revealed no significant interaction of task and language group, while the verbal tasks showed the opposite results. These findings suggest that the advantages in cognitive control extended beyond bilingualism to bidialectalism. Moreover, the bidialectal advantage was found in some tasks which involved more attentional and inhibitory control and had a high or intermediate level of task difficulty, and was absent in other tasks. [ABSTRACT FROM AUTHOR]

A recent review article by Braem et al. (2019, Trends in Cognitive Sciences) summarises some of the major challenges associated with investigating the dynamics of cognitive control in conflict tasks and recommends steps that researchers can take to minimise these challenges. This commentary highlights two further considerations for researchers studying the dynamics of cognitive control. First, researchers should consider analysing effects stemming from trial n - 2 to identify (a) how the congruency sequence effect emerges over a longer series of trials and (b) whether residual feature-integration effects remain in confound-minimised designs. Second, data from hand-tracking studies indicates that the dynamics observed in button-press measures of response time reflect the functioning of dissociable processes. Consequently, researchers should consider how the various manipulations used to investigate the dynamics of cognitive control might impact different processes underlying performance. [ABSTRACT FROM AUTHOR]

An astonishing aspect of human cognitive flexibility concerns the ability to efficiently convert complex symbolic instructions into novel behaviors. In such ability, the rapid transformation of relevant content into action plans is particularly crucial as it allows for reflexive, automatic-like execution of merely instructed task sets. However, little is known about the mechanisms that give rise to this transformation. In the current study, we test the hypothesis that novel instructions held in working memory are reformatted into action-oriented representations when selective attention prioritizes their content. To do so, we devised a paradigm in which participants first encoded 4 S-R mappings and later, a retro-cue selected two of them. We first found that participants can benefit from retro-cues during the implementation of novel task-sets. Then, across two preregistered experiments, we observed that cued mappings (but not uncued ones) induced intention-based reflexivity, suggesting that only these entered an action-oriented state. Altogether, our results reveal that selective attention prioritizes relevant novel instructed content, playing an important role in its prospective reformatting into an action-bound task set. [ABSTRACT FROM AUTHOR]

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. • The CSE observed in confound-minimized tasks is modulated by the congruency repetition type of the previous trial • The multiple-expectancies account is introduced to explain the effect of the previous trial's congruency repetition type • Repetition-priming confounds remained in versions of the flanker, Simon, and Stroop tasks designed to minimize confounds • No evidence of lingering repetition-priming confounds were observed in confound-minimized versions of the prime-probe task [ABSTRACT FROM AUTHOR]