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Control regions in the brain are thought to provide signals that configure the brain's moment-to-moment information processing. Previously, we identified regions that carried signals related to task-control initiation, maintenance, and adjustment. Here we characterize the interactions of these regions by applying graph theory to resting state functional connectivity MRI data. In contrast to previous, more unitary models of control, this approach suggests the presence of two distinct task-control networks. A frontoparietal network included the dorsolateral prefrontal cortex and intraparietal sulcus. This network emphasized start-cue and error-related activity and may initiate and adapt control on a trial-by-trial basis. The second network included dorsal anterior cingulate/medial superior frontal cortex, anterior insula/frontal operculum, and anterior prefrontal cortex. Among other signals, these regions showed activity sustained across the entire task epoch, suggesting that this network may control goal-directed behavior through the stable maintenance of task sets. These two independent networks appear to operate on different time scales and affect downstream processing via dissociable mechanisms.

In task-switching paradigms, Switch Positivity, the N2 difference wave, and the P3 difference wave are typically observed in the cue-target interval (CTI) design, where the cue precedes the target. The ERP components are indicative of task-set control processes (i.e., task-set reconfiguration and task-set inertia). However, in the composite design, where the cue and target appear simultaneously, these components are absent. Previous research has hypothesized that in the composite design task-switching experiments, participants may employ compound retrieval strategies based on associative learning to complete the tasks. This strategy circumvents task rules, thereby eliminating ERP components related to task-set control. This study aims to examine whether the use of compound retrieval strategies affects the task-set related ERP components. In Experiment 1, we manipulated participants' semantic understanding of the target stimuli to control their strategies. Participants in the compound retrieval group exclusively used the compound retrieval strategy, while those in the control group could employ both the compound retrieval strategy and task rules. In Experiment 2, we varied the number of target stimuli to influence participants' strategies, with participants in the task rule group utilizing task rules, and those in the control group permitted to use both task rules and the compound retrieval strategy. The results revealed that Switch Positivity, the N2 difference wave, and the P3 difference wave were absent across all group conditions, regardless of the strategies employed. These findings suggest that the disappearance of these ERP components in the composite design is not attributable to the use of compound retrieval strategies.

One of the most fundamental distinctions in cognitive psychology is between processing that is \"controlled\" and processing that is \"automatic.\" The widely held automatic processing account of visual word identification asserts that, among other characteristics, the presentation of a well-formed letter string triggers sublexical, lexical, and semantic activation in the absence of any intention to do so. Instead, the role of intention is seen as independent of stimulus identification and as restricted to selection for action using the products of identification (e.g., braking in response to a sign saying \"BRIDGE OUT\"). We consider four paradigms with respect to the role of an intention-defined here as a \"task set\" indicating how to perform in the current situation-when identifying single well-formed letter strings. Contrary to the received automaticity view, the literature regarding each of these paradigms demonstrates that the relation between an intention and stimulus identification is constrained in multiple ways, many of which are not well understood at present. One thing is clear: There is no simple relation between an intention, in the form of a task set, and stimulus identification. Automatic processing of words, if this indeed ever occurs, certainly is not a system default. L'une des distinctions les plus fondamentales en psychologie cognitive est celle entre le traitement « contrôlé » et le traitement « automatique ». Le concept du traitement automatique de l'identification visuelle des mots, largement répandu, affirme que, parmi d'autres caractéristiques, la présentation d'une chaîne de lettres bien formée déclenche une activation sublexicale, lexicale et sémantique en l'absence de toute intention de le faire. Au contraire, le rôle de l'intention est considéré comme indépendant de l'identification du stimulus et limité à la sélection d'une action utilisant les produits de l'identification (par exemple, freiner en apercevant un panneau indiquant « PONT EN RÉFECTION »). Nous examinons quatre paradigmes concernant le rôle d'une intention - définie ici comme un « ensemble de tâches » indiquant comment agir dans la situation actuelle - lors de l'identification de chaînes de lettres simples et bien formées. Contrairement à l'idée reçue de l'automaticité, la littérature concernant chacun de ces paradigmes démontre que la relation entre une intention et l'identification d'un stimulus est limitée de multiples façons, dont beaucoup ne sont pas bien comprises à l'heure actuelle. Une chose est claire : il n'existe pas de relation simple entre une intention, sous la forme d'un ensemble de tâches, et l'identification du stimulus. Le traitement automatique des mots, s'il a lieu, n'est certainement pas un défaut du système. Public Significance Statement With the extensive practice that readers have in processing words, many theorists argue that this skill becomes \"automatic,\" in the sense of occurring necessarily and without intention. In this article, we argue that there is considerable evidence against the reading of individual words being \"automatic\" in that particular sense. In many situations, intention demonstrably matters. We examine several frequently studied tasks that involve single words (and nonwords, like \"mantiness\") and show that the context in which they occur is important for understanding how such stimuli are processed. The \"task set\" that people adopt-their approach to the particular situation-and when they adopt that set both play pivotal roles in how words are processed. Consequently, the concept of automaticity as typically defined is too broad to capture the many subtleties involved in the skill of visual word recognition.

Recent research demonstrated that mere presentation of a task cue influences subsequent unconscious semantic priming by attentional sensitization of related processing pathways. The direction of this influence depended on task-set dominance. Dominant task sets with a compatible cue-task mapping were supposed to be rapidly suppressed, while weak task sets showed more sustainable activation. Building on this research, we manipulated cue-task compatibility as instance of task-set dominance in two experiments and tested how masked semantic priming was influenced by actually performing the cued task (induction-task trials) or by mere cue presentation (task cue-only trials). In induction-task trials, the results of earlier research were replicated; semantic priming was larger following a semantic induction task compared to a perceptual induction task. In task cue-only trials, priming effects were reversed compared to induction-task trials in both experiments. Priming was larger for a perceptual compared to a semantic task set in task cue-only trials, indicating suppression of task sets following mere cue presentation in preparation for the upcoming lexical decision task. This notion of an inhibition of task sets after mere cue presentation was further supported by switching-related costs and changes of task-set implementation throughout the experiment. The absence of a moderator role of cue-task compatibility for task cue effects on priming in the present study suggests that the precise time course of task-set activation and inhibition in response to task cues as a function of cue-task compatibility might depend on specific experimental settings.

The ability to follow explicit rules improves dramatically during the course of childhood, but relatively little is known about the changes in brain structure and function that underlie this behavioral improvement. Drawing from neuroscientific studies in human adults and other animals, as well as from an emerging literature in developmental cognitive neuroscience, we propose a brain-based account of the development of rule use in childhood. This account focuses on four types of rules represented in different parts of the prefrontal cortex: simple rules for reversing stimulus--reward associations, pairs of conditional stimulus--response rules (both univalent and bivalent), and higher-order stimulus--response rules for selecting among task sets. It is hypothesized that the pattern of developmental changes in rule use reflects the different rates of development of specific regions within the prefrontal cortex.

The ability to prepare for an action improves the speed and accuracy of its performance. While many studies indicate that behavior performance continues to improve throughout childhood and adolescence, it remains unclear whether or how preparatory processes change with development. Here, we used a rapid event-related fMRI design in three age groups (8–12, 13–17, 18–25years) who were instructed to execute either a prosaccade (look toward peripheral target) or an antisaccade (look away from target) task. We compared brain activity within the core fronto-parietal network involved in saccade control at two epochs of saccade generation: saccade preparation related to task instruction versus saccade execution related to target appearance. The inclusion of catch trials containing only task instruction and no target or saccade response allowed us to isolate saccade preparation from saccade execution. Five regions of interest were selected: the frontal, supplementary, parietal eye fields which are consistently recruited during saccade generation, and two regions involved in top down executive control: the dorsolateral prefrontal and anterior cingulate cortices. Our results showed strong evidence that developmental improvements in saccade performance were related to better saccade preparation rather than saccade execution. These developmental differences were mostly attributable to children who showed reduced fronto-parietal activity during prosaccade and antisaccade preparation, along with longer saccade reaction times and more incorrect responses, compared to adolescents and adults. The dorsolateral prefrontal cortex was engaged similarly across age groups, suggesting a general role in maintaining task instructions through the whole experiment. Overall, these findings suggest that developmental improvements in behavioral control are supported by improvements in effectively presetting goal-appropriate brain systems. •Response times and rate of successful responses improve from childhood to adulthood.•Fronto-parietal network was examined during task preparation vs. task execution.•BOLD activation consistently increased with development during task preparation.•Effects of age were observed in two task contexts with different cognitive demands.•Age-related improvements in task performance are mainly related to task preparation.

In previous research, relative response speed was revealed to have been used as a predictive cue to guide attention to a target location, in a phenomenon known as “cueing by response.” In this study, we explored whether responses can implicitly induce the use of cognitive control, especially in selecting and implementing task-sets. Participants were trained to perform tasks corresponding to different task cues during the training phase. Unbeknownst to participants, the response-contingent group’s response to the previous trial determined task type in the subsequent trial, while that of the random group was randomly determined. When the task cue was removed in the testing phase, the percentage of correctly selected response-contingent tasks of the response-contingent group was at a greater level than the chance and the random group, implying that cueing by response can activate appropriate task-sets. The perceptual stimuli did not modulate the task cueing by response, and the response was directly associated with the task. Thus, the results show that top-down control can be carried out even without conscious awareness, using response as a novel type of cue.

Accurately evaluating multi-core embedded systems remains a major challenge, as existing benchmarking methods and tools fail to reproduce realistic workloads with inter-core contentions. This study introduces a benchmark framework for Linux-based embedded systems that integrates a synthetic task-set generation model capable of reproducing both computational and contention characteristics observed in real-world applications. Applying this benchmark to three Linux kernel variants on a 16-core embedded platform, we have identified distinct scalability patterns and contention sensitivities among kernel configurations. The results mainly demonstrate the framework’s capability to reveal performance characteristics under Linux, but the proposed methodology itself has high portability and extendability by design to support various multi-core platforms including the RTOS-based ones.

Fitts’ Law is one of the most robust and well-studied principles in psychology. It holds that movement time (MT) for target-directed aiming movements increases as a function of target distance and decreases as a function of target width. The purpose of this study was to determine whether Fitts’ Law is affected not only by the demands of the target on the current trial but also by the requirements for performance on the previous trial. Experiments 1 and 2 examined trial-to-trial effects of varying target width; Experiment 3 examined trial-to-trial effects of varying target distance. The findings from Experiments 1 and 2 showed that moving a finger or cursor towards a large object on a previous trial shortened the movement time on the current trial, whereas the opposite occurred with a small object. In contrast, target distance on the previous trial had no effect on movement time on the current trial. These findings suggest that performance on trial n has a clear and predictable effect on trial n+1 (at least for target width) and that Fitts’ Law as it is normally expressed does not accurately predict performance when the width of the target varies from trial to trial.

In figure–ground organization, the figure is defined as a region that is both “shaped” and “nearer.” Here we test whether changes in task set and instructions can alter the outcome of the cross-border competition between figural priors that underlies figure assignment. Extremal edge (EE), a relative distance prior, has been established as a strong figural prior when the task is to report “which side is nearer?” In three experiments using bipartite stimuli, EEs competed and cooperated with familiar configuration, a shape prior for figure assignment in a “which side is shaped?” task.” Experiment 1 showed small but significant effects of familiar configuration for displays sketching upright familiar objects, although “shaped-side” responses were predominantly determined by EEs. In Experiment 2 , instructions regarding the possibility of perceiving familiar shapes were added. Now, although EE remained the dominant prior, the figure was perceived on the familiar-configuration side of the border on a significantly larger percentage of trials across all display types. In Experiment 3 , both task set (nearer/shaped) and the presence versus absence of instructions emphasizing that familiar objects might be present were manipulated within subjects. With familiarity thus “primed,” effects of task set emerged when EE and familiar configuration favored opposite sides as figure. Thus, changing instructions can modulate the weighing of figural priors for shape versus distance in figure assignment in a manner that interacts with task set. Moreover, we show that the influence of familiar parts emerges in participants without medial temporal lobe/ perirhinal cortex brain damage when instructions emphasize that familiar objects might be present.