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Cognitive stability, the ability to focus on a current task, and cognitive flexibility, the ability to switch between different tasks, are traditionally conceptualized as opposing end-points on a one-dimensional continuum. This assumption obligates a stability-flexibility trade-off - greater stability equates to less flexibility, and vice versa. In contrast, a recent cued task-switching study suggested that stability and flexibility can be regulated independently, evoking a two-dimensional perspective where trade-offs are optional (Geddert & Egner, Journal of Experimental Psychology: General, 151, 3009-3027, 2022). This raises the question of under what circumstances trade-offs occur. We here tested the hypothesis that trade-offs are guided by cost-of-control considerations whereby stability and flexibility trade off in contexts that selectively promote stability or flexibility, but not when neither or both are promoted. This proposal was probed by analyzing whether a trial-level metric of a stability-flexibility trade-off, an interaction between task-rule congruency and task sequence, varied as a function of a broader block-level context that independently varied demands on stability or flexibility by manipulating the proportion of incongruent and switch trials, respectively. In Experiment 1, we reanalyzed data from Geddert and Egner, Journal of Experimental Psychology: General, 151, 3009-3027, (2022); Experiment 2 was a conceptual replication with a design tweak that controlled for potential confounds due to local trial history effects. The experiments produced robust evidence for independent stability and flexibility adaptation, and for a context-dependent expression of trial-level stability-flexibility trade-offs that generally conformed to the cost-of-control predictions. The current study thus documents that stability-flexibility trade-offs are not obligatory but arise in contexts where either stability or flexibility are selectively encouraged.

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An underlying hypothesis for broad transfer from cognitive training is that the regional brain signals engaged during the training task are related to the transfer tasks. However, it is unclear whether the brain activations elicited from a specific cognitive task can generalize to performance of other tasks, esp. in normal aging where cognitive training holds much promise. In this large dual-site functional magnetic resonance imaging (fMRI) study, we aimed to characterize the neurobehavioral correlates of task-switching in normal aging and examine whether the task-switching-related fMRI-blood-oxygen-level-dependent (BOLD) signals, engaged during varieties of cognitive control, generalize to other tasks of executive control and general cognition. We therefore used a hybrid blocked and event-related fMRI task-switching paradigm to investigate brain regions associated with multiple types of cognitive control on 129 non-demented older adults (65-85 years). This large dataset provided a unique opportunity for a data-driven partial least squares-correlation approach to investigate the generalizability of multiple fMRI-BOLD signals associated with task-switching costs to other tasks of executive control, general cognition, and demographic characteristics. While some fMRI signals generalized beyond the scanned task, others did not. Results indicate right middle frontal brain activation as detrimental to task-switching performance, whereas inferior frontal and caudate activations were related to faster processing speed during the fMRI task-switching, but activations of these regions did not predict performance on other tasks of executive control or general cognition. However, BOLD signals from the right lateral occipital cortex engaged during the fMRI task positively predicted performance on a working memory updating task, and BOLD signals from the left post-central gyrus that were disengaged during the fMRI task were related to slower processing speed in the task as well as to lower general cognition. Together, these results suggest generalizability of these BOLD signals beyond the scanned task. The findings also provided evidence for the general slowing hypothesis of aging as most variance in the data were explained by low processing speed and global low BOLD signal in older age. As processing speed shared variance with task-switching and other executive control tasks, it might be a possible basis of generalizability between these tasks. Additional results support the dedifferentiation hypothesis of brain aging, as right middle frontal activations predicted poorer task-switching performance. Overall, we observed that the BOLD signals related to the fMRI task not only generalize to the performance of other executive control tasks, but unique brain predictors of out-of-scanner performance can be identified.

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When performing synchronous hand and foot movements, the way the limbs are synchronized differs depending on the mode of control. When performed in a reaction time (RT) paradigm (reactive control), EMG onsets become synchronized resulting in asynchronous displacement onset. However, when the same movement is performed as an anticipation-timing task (predictive control), displacement onset is synchronized by unconsciously introducing a small delay between EMG onsets. The present experiment investigated the reprogramming costs associated with switching between predictive and reaction control modes. Participants (N = 12, 6F) were asked to simultaneously lift their right heel and right hand in an anticipation-timing task when a rotating clock hand reached a specified target. On some trials, an auditory stimulus was presented either 250 ms or 500 ms before the target and participants were instructed to execute the synchronous movement as quickly as possible after the signal (i.e., switch to reactive mode). Results showed that when the auditory stimulus was delivered 250 ms before the target, participants were unable to switch to a reactive control mode but did switch when the auditory stimulus was presented 500 ms before the target. As expected, the RT on switch trials was substantially longer (∼230 ms) than a simple RT control condition but was also significantly longer (∼130 ms) than a choice RT control condition. These results indicate that switching between control modes for a task involving the same musculature incurs reprogramming costs that are even greater than the time required to program the response de novo.

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Preparatory control in task-switching has been suggested to rely upon a set of distributed regions within a frontoparietal network, with frontal and parietal cortical areas cooperating to implement switch-specific preparation processes. Although recent causal evidence using transcranial magnetic stimulation (TMS) have generally supported this model, alternative results from both functional neuroimaging and neurophysiological studies have questioned the switch-specific role of both frontal and parietal cortices. The aim of the present study was to clarify the involvement of prefrontal and parietal areas in preparatory cognitive control. With this purpose, an fMRI study was conducted to identify the brain areas activated during cue events in a task-switching paradigm, indicating whether to switch or to repeat among numerical tasks. Then, TMS was applied over the specific coordinates previously identified through fMRI, that is, the right inferior frontal gyrus (IFG) and right intraparietal sulcus (IPS). Results revealed that TMS over the right IFG disrupted performance in both switch and repeat trails in terms of delayed responses as compared to Sham condition. In contrast, TMS over the right IPS selectively interfered performance in switch trials. These findings support a multi-component model of executive control with the IFG being involved in more general switch-unspecific process such as the episodic retrieval of goals, and the IPS being related to the implementation of switch-specific preparation mechanisms for activating stimulus-response mappings. The results are discussed within the framework of contemporary hierarchical models of prefrontal cortex organization, suggesting that distinct prefrontal areas may carry out coordinated functions in preparatory control.

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Core constructs such as working memory, task switching, and processing speed in cognitive psychology research have prominent predictive roles in K12 students' academic performance. Specifically, considerable empirical work shows that variability in such capabilities is linked to differences in numerous academic outcomes. Moreover, there is an increasing awareness and acceptance of the malleability of cognitive abilities. Thus, an emerging strand of research focuses on the use of computerized cognitive training to improve cognitive skills. This project addresses this issue with high-risk students attending community day schools. An in-school cognitive training program implemented (for 30 min per day) at each school site resulted in improvements for working memory, task switching, and processing speed after six total hours of participation. The current results provide evidence for the changeability of what were once thought to be static skills. Equally important, this study highlights the effectiveness of computerized cognitive training and critically extends intervention-based work to a student group that has received little attention. Implications of this work for cognitive research and educational support programs are discussed.

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In everyday life, humans perform sequences of tasks. These tasks may be disrupted in people with obsessive-compulsive disorder (OCD). Symptoms, such as compulsions, can be considered sequential and often cause repetitions of tasks that disrupt daily living (e.g., checking the stove while cooking). Motor sequences have been used to study behavioral deficits in OCD. However, not all sequences are motor sequences. Some are more "abstract" in that they are composed of a series of tasks (e.g., chopping and stirring) rather than being dependent on individual actions or stimuli. These abstract task sequences require cognitive control mechanisms for their execution. Although theory has proposed deficits in these sequences in OCD as well, they have not been directly investigated. We tested the hypotheses that OCD participants exhibit deficits in the control mechanisms specific to abstract task sequences and more general flexible behavior (measured with task switching within the sequences), relative to health controls (HCs) and clinical controls (participants with anxiety disorders [ANX]). A total of 112 participants completed abstract task sequences consisting of simple categorization tasks. Surprisingly, participants with OCD did not perform worse than HCs or ANX. However, ANX participants showed impairments specific to sequential control that did not extend to more general flexible control. Thus, we showed a novel behavioral dissociation between OCD and ANX specific to abstract task sequential control. These results also implicate deficits in specific frontal sequential control neural circuitry in ANX and not in OCD, where implicit sequential deficits may more closely align with striatal circuits.

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Background: Cognitive flexibility, a vital component of executive function, entails the utilization of extended brain networks. Olfactory stimulation has been shown to influence various brain functions, particularly cognitive performance. Method: To investigate aroma inhalation's effects on brain activity dynamics associated with cognitive flexibility, 20 healthy adults were recruited to complete a set-shifting task during two experimental conditions: no aroma stimuli vs. lavender essential oil inhalation. Using Thomson's multitaper approach, the normalized power spectral density (NPSD) was assessed for five frequency bands. Results: Findings confirm that aroma inhalation significantly affects behavioral indices (i.e., reaction time (RT) and response accuracy) and electroencephalogram (EEG) signatures, especially in the frontal lobe. Participants showed a tremendous increase in theta and alpha NPSD, associated with relaxation, along with beta NPSD, associated with clear and fast thinking after inhaling the aroma. NPSD of the delta band, an indicator of the unconscious mind, significantly decreased when stimulated with lavender essential oil. Further, participants exhibited shorter RT and more accurate responses following aroma inhalation. Conclusion: Our findings revealed significant changes in oscillatory power and behavioral performance after aroma inhalation, providing neural evidence that olfactory stimulation with lavender essential oil may facilitate cognitive flexibility.

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Prior research on task switching has shown that the reconfiguration of stimulus-response mappings across trials is associated with behavioral switch costs. Here, we investigated the effects of switching representations of target-defining features in visual search (attentional templates). Participants searched for one of two color-defined target objects that changed predictably every two trials (Experiment 1) or every four trials (Experiment 2). Substantial costs were observed for search performance on target switch relative to target repeat trials. Preparatory target template activation processes were tracked by measuring N2pc components (indicative of attentional capture) to a rapid series of task-irrelevant color singleton probes that appeared during the interval between search displays, and either matched the currently relevant or the other target color. N2pcs to relevant target color probes emerged from 800 ms before search display onset on target repetition trials, reflecting the activation of a corresponding color template. Crucially, probe N2pcs only emerged immediately before target onset on target switch trials, indicating that preparatory template activation was strongly delayed. In contrast, irrelevant color singleton probes did not trigger N2pcs on either repeat or switch trials, suggesting the absence of any target template inertia across trials. These results show that switching the identity of search targets delays preparatory target template activation and impairs subsequent attentional guidance processes. They suggest that performance costs on switch versus repeat trials are associated with differences in the time course of task preparation.

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BACKGROUND: The aging population is increasing. Aging has been associated with some degree of cognitive decline, especially in functions such as cognitive flexibility. The voluntary task-switching paradigm is a novel model for studying this function. The aim of this work was to design and test a computerized instrument to assess cognitive flexibility with this paradigm. METHODS: A non-probabilistic and intentional sample of individuals aged 60 and above (N=57; M=70; SD=7.5), 72% of whom were women, was utilized. A general cognitive screening test (ACE III) and the "Coin Tossing" task, a computerized program consisting of four levels of complexity, were administered. RESULTS: A Wilcoxon test was used to contrast parity versus size responses (z(56)=-1.16, P=.24). To assess repetition bias, a Wilcoxon test was conducted between new and repeated responses (TR: z(56)=-1.81, P=.07 // Accuracy: z(56)=-6.33, P=.00). A repeated measures ANOVA was performed between reaction times before, during, and after a response change, F(1.02)=59.6, P<.01, η2=.937, B-1=1. And a repeated measures ANOVA between mean RTs per level, F(3)=7.92, P<.001, η2=.128, B-1=.98. CONCLUSIONS: The test was designed with a progressive structure across levels. The theoretical assumptions of the paradigm were partially demonstrated, showing its utility for the assessment and training of cognitive flexibility.

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Cognitive flexibility (CF) has been proposed as a potential trait marker in anorexia nervosa (AN), although findings have been inconsistent. To address this inconsistency, we applied a model that distinguishes between three subtypes of CF: task switching, switching sets, and stimulus-response mapping, which we then assessed using a paradigm-based task battery. The aim of the study was to investigate how AN is associated with these three CF subtypes. Thirty-three women with AN and 37 age- and education-matched controls performed a battery of computerized cognitive tasks to assess the three CF subtypes. Compared to the control group, individuals with AN exhibited poorer performance on the task switching and switching sets subtypes, as measured by response time switch cost, but not on the stimulus-response mapping subtype. No differences were found between the groups in response accuracy. Furthermore, switching sets as compared to the task switching and stimulus-response mapping subtypes was found to better explain the differences between the groups. These findings indicate a domain-specific impairment in CF among patients with AN, reflecting deficits observed in subtypes related to the disorder's characteristics, particularly that associated with visual perception. Therefore, CF impairment in AN should not be viewed dichotomously, but rather as a relative impairment that varies depending on the specific CF subtype.

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Positive affect has been shown to promote task-switching performance in healthy young adults. Given the well-documented age-related decline in executive functioning, we asked whether induced positive affect also helps to improve task-switching performance in older adults. Sixty-eight younger and older adults performed a switching task before and after they had watched cartoon clips (positive affect group) or documentaries (neutral affect group). Positive affect was associated with reduced error rates across all trial types in both age groups. In older adults, the increase in accuracy came at the expense of slower response times for task-switch trials, resulting in greater switch costs. This pattern of findings is inconsistent with the popular notion that positive affect supports greater cognitive flexibility. Instead, positive affect may trigger adjustments in response control settings - such as a shift in the speed-accuracy trade-off toward more cautious responding - depending on the experienced level of task difficulty.

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It is commonly assumed that inner speech-the experience of thought as occurring in a natural language-is a human universal. Recent evidence, however, suggests that the experience of inner speech in adults varies from near constant to nonexistent. We propose a name for a lack of the experience of inner speech-anendophasia-and report four studies examining some of its behavioral consequences. We found that adults who reported low levels of inner speech (N = 46) had lower performance on a verbal working memory task and more difficulty performing rhyme judgments compared with adults who reported high levels of inner speech (N = 47). Task-switching performance-previously linked to endogenous verbal cueing-and categorical effects on perceptual judgments were unrelated to differences in inner speech.

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The role of task priority on task selection in multi-task management is unclear based on prior work, leading to a common finding of 'priority neglect'. However, properties such as urgency and conflict may influence whether operators weigh priority in their decision. We examined the role of instructed task prioritization, bolstered by more urgent and conflicting conditions, on how operators select among emergent, concurrent tasks when multitasking. Using the Multi-Attribute Task Battery (MATB) multitasking platform we tested both an auditory communications task and a manual tracking task as the priority tasks. Results showed that instructed priority significantly increased target task selection under the conflicting task conditions for both tasks. Urgency itself may modulate whether instructions to prioritize affect task selection choices when multitasking, and therefore counter to prior results instructions may yet be useful for helping operators select a higher priority task under conflict, a generalizable effect to be further explored.

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Introduction: Task set inhibition supports optimal switching among tasks by actively suppressing the interference from recently executed competing task sets. It is typically studied in cued task-switching paradigms where there is no uncertainty about the task set or rule to prepare for on each trial. While inhibition has been shown to influence the speed and the accuracy of task execution, affecting task set retrieval, preparation, or implementation in conditions of task set switching, it remains uninvestigated whether it also affects rule selection under uncertainty. Methods: We implemented an ad-hoc four-rule card sorting task and categorized the rules selected by participants after a rule shift according to the recency of their last usage. We included a measure of working memory capacity (WMC) to control for its involvement in the rule selection process. Results: Participants exhibited a reduced preference for recently abandoned rules than less recently abandoned ones. Furthermore, we found that such a preference was not associated with WMC. Discussion: The results suggest that decision-making processes underlying rule inference and selection may be influenced by task-set inhibition, configuring as a conflict adjustment mechanism to the sequential history of rules application.

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A key element of human flexible behavior concerns the ability to continuously predict and prepare for sudden changes in tasks or actions. Here, we tested whether people can dynamically modulate task preparation processes and decision-making strategies when the identity of a to-be-performed task becomes uncertain. To this end, we developed a new paradigm where participants need to prepare for one of nine tasks on each trial. Crucially, in some blocks, the task being prepared could suddenly shift to a different task after a longer cue-target interval, by changing either the stimulus category or categorization rule that defined the initial task. We found that participants were able to dynamically modulate task preparation in the face of this task uncertainty. A second experiment shows that these changes in behavior were not simply a function of decreasing task expectancy, but rather of increasing switch expectancy. Finally, in the third and fourth experiment, we demonstrate that these dynamic modulations can be applied in a compositional manner, depending on whether either only the stimulus category or categorization rule would be expected to change.

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Models of social interaction dynamics have been powerful tools for understanding the efficiency of information spread and the robustness of task allocation in social insect colonies. How workers spatially distribute within the colony, or spatial heterogeneity degree (SHD), plays a vital role in contact dynamics, influencing information spread and task allocation. We used agent-based models to explore factors affecting spatial heterogeneity and information flow, including the number of task groups, variation in spatial arrangements, and levels of task switching, to study: (1) the impact of multiple task groups on SHD, contact dynamics, and information spread, and (2) the impact of task switching on SHD and contact dynamics. Both models show a strong linear relationship between the dynamics of SHD and contact dynamics, which exists for different initial conditions. The multiple-task-group model without task switching reveals the impacts of the number and spatial arrangements of task locations on information transmission. The task-switching model allows task-switching with a probability through contact between individuals. The model indicates that the task-switching mechanism enables a dynamical state of task-related spatial fidelity at the individual level. This spatial fidelity can assist the colony in redistributing their workforce, with consequent effects on the dynamics of spatial heterogeneity degree. The spatial fidelity of a task group is the proportion of workers who perform that task and have preferential walking styles toward their task location. Our analysis shows that the task switching rate between two tasks is an exponentially decreasing function of the spatial fidelity and contact rate. Higher spatial fidelity leads to more agents aggregating to task location, reducing contact between groups, thus making task switching more difficult. Our results provide important insights into the mechanisms that generate spatial heterogeneity and deepen our understanding of how spatial heterogeneity impacts task allocation, social interaction, and information spread.

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Athletes of skill-oriented sports (hereinafter referred to as "skilled athletes"), such as gymnasts and rhythmic gymnasts, have demonstrated better postural control than nonathletes. However, previous studies have mainly focused on single postural tasks and have not considered how skilled athletes use and allocate attentional resources during postural control. This research used the event-related potential (ERP) to explore the postural control performance of skilled athletes under cognitive processes and their utilization and allocation of attentional resources. A dual-task paradigm was used to simulate the actual situation in sports. 26 skilled athletes and 26 nonathletes were required to perform postural control and task-switching simultaneously. The results showed that skilled athletes demonstrated more postural control stability and a higher accuracy of task-switching than nonathletes in all dual tasks. Compared with nonathletes, they showed a stable enhanced N1 (electrodes: Oz, O1, and O2) amplitude during three postures. Moreover, larger N2 component on Fz, FCz, and Cz and theta band power was found in the frontal cortex (on Fz, FCz) of skilled athletes under feet together and single leg standing posture. The study illustrated that skilled athletes show greater frontal activation during dual tasks, which allows for more rational and flexible brain attentional resource input and allocation in cognitive processes, this may be due to long-term professional training, which enables them to have a higher level of automation of postural control and cognitive flexibility. This study's results offer valuable insights into the interplay between postural control and multitasking in skilled athletes, and its outcomes carry significant implications for the training and assessment of athletes across various sports.

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BACKGROUND: This study aimed to investigate how single-bout open-skill exercise (OSE), closed-skill exercise (CSE), and mixed-skill exercise intervention (MSE) influence executive function. METHOD: A total of 120 students aged between 18 and 25 were separated into three groups: closed-skill exercise, open-skill exercise, and mixed-skill exercise. A task-switching test was performed before and after a single bout of exercise intervention. The simple reaction time, choice reaction time, switch cost, and correction rate were tested in a task-switching test. The results were analyzed via a two-way analysis of variance, with a significance level of α = 0.05, to compare the effects of the intervention. RESULTS: Only open-skill exercise exhibited a significant effect on the simple reaction time (p < 0.05). In terms of choice reaction time and switch cost, all three intervention groups exhibited significant improvements, with no significant differences observed between the three groups (p < 0.05). The correction rate did not show a significant effect post-intervention, and no significant differences were observed between the groups. The correction rate showed no significant effect after the intervention or between groups. CONCLUSION: All three types of exercise can shorten choice reaction time and switch cost, but only OSE can reduce simple reaction time.

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BACKGROUND: Psychomotor disturbances are observed across psychiatric disorders and often manifest as psychomotor slowing, agitation, disorganized behavior, or catatonia. Psychomotor function includes both cognitive and motor components, but the neural circuits driving these subprocesses and how they relate to symptoms have remained elusive for centuries. METHODS: We analyzed data from the HCP-EP (Human Connectome Project for Early Psychosis), a multisite study of 125 participants with early psychosis and 58 healthy participants with resting-state functional magnetic resonance imaging and clinical characterization. Psychomotor function was assessed using the 9-hole pegboard task, a timed motor task that engages mechanical and psychomotor components of action, and tasks assessing processing speed and task switching. We used multivariate pattern analysis of whole-connectome data to identify brain correlates of psychomotor function. RESULTS: We identified discrete brain circuits driving the cognitive and motor components of psychomotor function. In our combined sample of participants with psychosis (n = 89) and healthy control participants (n = 52), the strongest correlates of psychomotor function (pegboard performance) (p < .005) were between a midline cerebellar region and left frontal region and presupplementary motor area. Psychomotor function was correlated with both cerebellar-frontal connectivity (r = 0.33) and cerebellar-presupplementary motor area connectivity (r = 0.27). However, the cognitive component of psychomotor performance (task switching) was correlated only with cerebellar-frontal connectivity (r = 0.19), whereas the motor component (processing speed) was correlated only with cerebellar-presupplementary motor area connectivity (r = 0.15), suggesting distinct circuits driving unique subprocesses of psychomotor function. CONCLUSIONS: We identified cerebellar-cortical circuits that drive distinct subprocesses of psychomotor function. Future studies should probe relationships between cerebellar connectivity and psychomotor performance using neuromodulation.

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Task switching refers to a set of cognitive processes involved in shifting attention from one task to another. In recent years, researchers have applied transcranial direct current stimulation (tDCS) to investigate the causal relationship between the parietal cortex and task switching. However, results from available studies are highly inconsistent. This may be due to the unclear understanding of the underlying mechanisms. Therefore, the current study utilized event-related potential (ERP) analysis to investigate the modulatory effects of tDCS on task-switching processes. Twenty-four subjects were recruited to perform both predictable and unpredictable parity/magnitude tasks under anodal (RA) and sham conditions. The results showed no significant changes in behavioral performance. However, marked tDCS-induced ERP changes were observed. Specifically, for the predictable task switching, compared with the sham condition, the target-N2 component occurred significantly earlier for switch trials than repeat trials under the RA condition in males, while no difference was found in females. For unpredictable task switching, under the sham condition, the P2 peak was significantly larger for switch trials compared with repeat trials, whereas this difference was not observed under the RA condition. These results indicated the causal relationship between the right parietal cortex and exogenous adjustment processes involved in task switching. Moreover, anodal tDCS over the right parietal cortex may lead to the manifestation of gender differences.

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