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The goal of this study was to investigate the neural dynamics of error processing and post-error adjustments in cognitive control and attention to a cognitive task in schizophrenia. We adopted a time-frequency approach in order to examine activity in the theta and alpha frequency bands as indices of cognitive control and attentional engagement. The results showed that error processing was characterized by increases in theta-band activity, accompanied by decreases in alpha-band activity, in both healthy control participants and participants with schizophrenia. However, both the theta and alpha effects were significantly reduced in participants with schizophrenia. Post-error increases in theta activity were associated with improved accuracy on subsequent trials in control participants but not in participants with schizophrenia. In addition, increases in alpha-band activity were found in the prestimulus period before partial attention lapses, but only for control participants and participants with schizophrenia with relatively low positive symptom severity. These results provide evidence for a deficit in cognitive control mechanisms mediated by midfrontal theta activity in schizophrenia, and suggest a particularly pronounced deficit in patients' ability to engage adaptive control mechanisms following errors. Our results also indicate that partial attention lapses can be indexed in both control participants and participants with schizophrenia by increases in alpha activity, but that in schizophrenia this varies as a function of positive symptom severity. We suggest that disrupted theta-band function represents a key deficit of schizophrenia, whereas disruptions in the alpha band may be the byproduct of atypically regulated attention.

This study tested whether self-reports of childhood adversity would predict altered error processing under emotional versus non-emotional task conditions. N = 99 undergraduates completed two selective attention tasks, a traditional color-word Stroop task and a modified task using emotional words, while EEG was recorded. Participants also completed self-report measures of adverse and positive childhood experiences, executive functioning, depression, current stress, and emotion regulation. Reports of adversity were robustly correlated with self-reported challenges in executive functioning, even when controlling for self-reported depression and stress, but adversity was not correlated with task performance. With regard to neural markers of error processing, adversity predicted an enhanced error-related negativity and blunted error-positivity, but only during the emotion-word blocks of the task. Moreover, error-related changes in alpha oscillations were predicted by adversity, in a pattern that suggested less error responsiveness in alpha patterns during the emotion block, compared to the color block, among participants with higher adversity. Overall, results indicate alterations in error monitoring associated with adversity, such that in an emotional context, initial error detection is enhanced and sustained error processing is blunted, even in the absence of overt performance changes., (© 2024 Society for Psychophysiological Research.)

A prime goal of psychological science is to understand how humans can flexibly adapt to rapidly changing contexts. The foundation of this cognitive flexibility rests on contextual adjustments of cognitive control, which can be tested using the list-wide proportion congruency effect (LWPC). Blocks with mostly incongruent (MI) trials show smaller conflict interference effects compared to blocks with mostly congruent (MC) trials. A critical debate is how proactive and reactive control processes drive contextual adjustments. In this preregistered study (N = 30), we address this conundrum, by using the theta rhythm as a key neural marker for cognitive control. In a confound-minimized Stroop paradigm with short alternating MC and MI blocks, we tested reaction times, error rates, and participants' individualized theta activity (2-7 Hz) in the scalp-recorded electroencephalogram. An LWPC effect was found for both, reaction times and error rates. Importantly, the results provided clear evidence for reactive control processes in the theta rhythm: Theta power was higher in rare incongruent compared with congruent trials in MC blocks, but there was no such modulation in MI blocks. However, regarding proactive control, there were no differences in sustained theta power between MC and MI blocks. A complementary analysis of the alpha activity (8-14 Hz) also revealed no evidence for sustained attentional resources in MI blocks. These findings suggest that contextual adjustments rely mainly on reactive control processes in the theta rhythm. Proactive control, in the present study, may be limited to a flexible attentional shift but does not seem to require sustained theta activity., (© 2024 The Author(s). Psychophysiology published by Wiley Periodicals LLC on behalf of Society for Psychophysiological Research.)

Although the relationships among acute stress, cardiorespiratory fitness (CRF), and cognitive function have been examined, whether CRF is related to behavioral and neuroelectric indices of inhibitory control following acute stress remains unknown. The purpose of the current study was to investigate the combined influence of acute stress and CRF on inhibitory control. Participants, aged 20-30 years, were stratified into the Higher-Fit (n = 31) and the Lower-Fit (n = 32) groups, and completed a Stroop task following the modified Maastricht Acute Stress Test (MAST) in the stress condition and the sham-MAST in the non-stress condition, during which electroencephalography was recorded. Behavioral (i.e., response time and accuracy) and neuroelectric (N2 and P3b components of the event-related potential) outcomes of inhibitory control were obtained. While the Higher-Fit group demonstrated shorter response times and higher accuracy than the Lower-Fit group following both the MAST and the sham-MAST, they also exhibited selective benefits of acute stress on inhibitory control performance (i.e., decreased response times and diminished interference scores). CRF-dependent alterations in neuroelectric indices were also observed, with the Higher-Fit group displaying smaller N2 and greater P3b amplitudes than the Lower-Fit group following the sham-MAST, and increased N2 and attenuated P3b amplitudes following the MAST. Collectively, these findings not only confirm the positive relationship between CRF and inhibitory control but also provide novel insights into the potential influence of CRF on inhibitory control and associated neuroelectric activity following acute stress., (© 2024 Society for Psychophysiological Research.)

This article presents an experiment (N = 127 university students) testing whether the previously found impact of conflict primes on effort-related cardiac response is moderated by objective task difficulty. Recently, it has been shown that primed cognitive conflict increases cardiac pre-ejection period (PEP) reactivity-an index of effort intensity-during the performance of relatively easy tasks. This effect could be attributed to conflict-related negative affect. Consequently, as it has been shown for other types of negative affect, we expected conflict primes' effect to be task-context dependent and thus to be moderated by objective task difficulty. In a between-persons design, we manipulated conflict via embedded pictures of conflict-related vs. non-conflict-related Stroop items in a memory task. We expected primed conflict to increase effort in a relatively easy version of the task but to lead to disengagement when task difficulty was objectively high. PEP reactivity corroborated our predictions. Rather than always increasing effort, cognitive conflict's effect on resource mobilization was context-dependent and resulted in weak responses in a difficult task., (© 2024 The Authors. Psychophysiology published by Wiley Periodicals LLC on behalf of Society for Psychophysiological Research.)

Previous work has indicated that individual differences in cognitive performance can be predicted by characteristics of resting state oscillations, such as individual peak alpha frequency (IAF). Although IAF has previously been correlated with cognitive functions, such as memory, attention, or mental speed, its link to cognitive conflict processing remains unexplored. The current work investigated the relationship between IAF and inhibitory cognitive control in two well-established conflict tasks, Stroop and Navon task, while also controlling for alpha power, theta power, and the 1/f offset of aperiodic broadband activity. In Bayesian analyses on a large sample of 127 healthy participants, we found substantial evidence against the assumption that IAF predicts individual abilities to spontaneously exert cognitive control. Similarly, our findings yielded substantial evidence against links between cognitive control and resting state power in the alpha and theta bands or between cognitive control and aperiodic 1/f offset. In sum, our results challenge frameworks suggesting that an individual's ability to spontaneously engage attentional control networks may be mirrored in resting state EEG characteristics., (© 2024 The Authors. Psychophysiology published by Wiley Periodicals LLC on behalf of Society for Psychophysiological Research.)

The locus coeruleus-norepinephrine (LC-NE) system, which regulates arousal levels, is important for cognitive control, including emotional conflict resolution. Additionally, the LC-NE system is implicated in P300 generation. If the P300 is mediated by the LC-NE system, and considering the established correlations between LC activity and pupil dilation, P300 amplitude should correlate with task-evoked (phasic) pupil dilation on a trial-by-trial basis. However, prior studies, predominantly utilizing oddball-type paradigms, have not demonstrated correlations between concurrently recorded task-evoked pupil dilation and P300 responses. Using a recently developed emotional face-word Stroop task that links pupil dilation to the LC-NE system, here, we examined both intra- and inter-individual correlations between task-evoked pupil dilation and P300 amplitude. We found that lower accuracy, slower reaction times, and larger task-evoked pupil dilation were obtained in the incongruent compared to the congruent condition. Furthermore, we observed intra-individual correlations between task-evoked pupil dilation and P300 amplitude, with larger pupil dilation correlating with a greater P300 amplitude. In contrast, pupil dilation did not exhibit consistent correlations with N450 and N170 amplitudes. Baseline (tonic) pupil size also showed correlations with P300 and N170 amplitudes, with smaller pupil size corresponding to larger amplitude. Moreover, inter-individual differences in task-evoked pupil dilation between the congruent and incongruent conditions correlated with differences in reaction time and P300 amplitude, though these effects only approached significance. To summarize, our study provides evidence for a connection between task-evoked pupil dilation and P300 amplitude at the single-trial level, suggesting the involvement of the LC-NE system in P300 generation., (© 2023 Society for Psychophysiological Research.)

Conflicts in working memory (WM) can occur when retrieval cues activate competing items, which impairs the efficiency of retrieval. It has recently been shown that WM retrieval adapts similarly to these conflicts as predicted by conflict monitoring theory for selective attention tasks. Here, we utilized event-related potentials (ERPs) to investigate whether conflict and adaptive control in WM are reflected by the same neural markers that have previously been described for selective attention tasks. In our task, participants encoded two differently colored memory lists that contained four digits each (i.e., 2 5 7 1 and 4 5 9 1), and had to recognize whether a probe item from a specific list and position was correct or incorrect. Conflict during retrieval emerged when digits at corresponding positions (e.g., 2 and 5 at the first position) were different (incongruent), but not when these digits were the same (congruent). In behavioral data, we found a congruency sequence effect, that is, responses to incongruent probe items were slower, and this effect was reduced following trials with incongruent probe items. In ERPs, this behavioral marker of adaptive control was accompanied by two effects. First, congruency affected the amplitude of an N450, and this conflict effect was reduced after incongruent trials. Second, the posterior P3 amplitude varied with the congruency of the current and the previous trial. Both results resemble those found for the Stroop task and thus highlight the similarity between conflict and adaptive control in WM and selective attention tasks., (© 2023 The Authors. Psychophysiology published by Wiley Periodicals LLC on behalf of Society for Psychophysiological Research.)

Acute aerobic exercise has been shown to benefit inhibitory control; however, less attention has been devoted to the effects of varying intensity and duration with a predetermined exercise volume. The current study assessed the influence of three distinct exercise conditions, each equated with a predesignated exercise volume but varied in terms of exercise durations and intensities, on inhibitory control utilizing both behavioral and neuroelectric measures obtained among late-middle-aged and older adults. Thirty-four adults (61.76 ± 0.80 years) completed three exercise conditions [i.e., a 30-min low-intensity exercise (LIE), a 20-min moderate-intensity exercise (MIE), and a 16-min high-intensity exercise (HIE)] and a non-exercise reading control condition (CON) on separate days. The exercise volumes of LIE and HIE were designed to match the exercise volume of MIE. Following cessation of each condition, the Stroop task was performed while event-related potentials were recorded. Improved behavioral performance (i.e., shorter response time, higher accuracy, and smaller interference scores) was observed after LIE, MIE, and HIE than CON (ps < .005). Additionally, whereas a larger P3b amplitude was only observed following MIE compared to CON (p < .01), larger N2 and smaller N450 amplitudes were observed following all three exercise conditions compared to CON (ps < .005). These findings suggested that while MIE may provide additional benefits for attentional resource allocation, exercise conditions volume matched to MIE resulted in superior inhibitory control, paralleled by modulations of the neural underpinnings of conflict monitoring/detection., (© 2023 Society for Psychophysiological Research.)

The conflict monitoring theory postulates that conflict detection is initiated in the anterior cingulate cortex (ACC), indexed by midfrontal theta oscillations in the electroencephalogram (EEG). Recent research suggested that distractor detection (in the Eriksen flanker task) can be initiated relatively early by attentional control processes in the occipital lobe. Whether attentional control is also involved in the detection of stimulus-response overlapping conflict in the Stroop task is yet unclear. In the present study, we analyzed EEG time-frequency data (N = 47) to investigate the contribution of early attentional control processes to the detection of response conflict and semantic conflict in a lateralized version of the color-word Stroop task. The behavioral results showed significant conflict effects in response times (RT). The EEG results showed a prominent midfrontal response conflict effect in total theta power (4-8 Hz). Importantly, detection of response conflict and semantic conflict was observed in posterior delta/theta power (2-8 Hz), which was lateralized depending on the presentation side of the irrelevant Stroop words. In explorative regression analysis, both the midfrontal and the posterior response conflict effects predicted the size of response conflict errors. These results suggest that attentional control processes in posterior areas contribute to the initiation of response-conflict detection in the Stroop task. The findings are consistent with the idea of a representational link between stimulus and response features, known as the common coding principle., (© 2022 The Authors. Psychophysiology published by Wiley Periodicals LLC on behalf of Society for Psychophysiological Research.)

Two experiments with N = 221 university students investigated the impact of primed cognitive conflict on effort assessed as cardiac response in tasks that were not conflict-related themselves. Manifest cognitive conflict in cognitive control tasks is confounded with objective response difficulty (e.g., in incongruent Stroop task trials). This makes conclusions about the effortfulness of cognitive conflict itself difficult. We bypassed this problem by administrating pictures of congruent versus incongruent Stroop task stimuli as conflict primes. As predicted, primed cognitive conflict increased cardiac pre-ejection period (PEP) responses in an easy attention task in Experiment 1. Accordingly, cognitive conflict itself is indeed effortful. This effect was replicated in an easy short-term memory task in Experiment 2. Moreover, as further predicted, the primed cognitive conflict effect on PEP reactivity disappeared when participants could personally choose task characteristics. This latter effect corresponds to other recent evidence showing that personal action choice shields against incidental affective influences on action execution and especially on effort-related cardiovascular response., (© 2022 The Authors. Psychophysiology published by Wiley Periodicals LLC on behalf of Society for Psychophysiological Research.)

This study aimed to clarify the effects of acute exercise and cardiovascular fitness on cognitive function using the Stroop test and event-related desynchronization ( ERD) in an aged population. Old adults (63.10 ± 2.89 years) were first assigned to either a high-fitness or a low-fitness group, and they were then subjected to an acute exercise treatment and a reading control treatment in a counterbalanced order. Alpha ERD was recorded during the Stroop test, which was administered after both treatments. Acute exercise improved cognitive performance regardless of the level of cognition, and old adults with higher fitness levels received greater benefits from acute exercise. Additionally, acute exercise, rather than overall fitness, elicited greater lower and upper alpha ERDs relative to the control condition. These findings indirectly suggest that the beneficial effects of acute exercise on cognitive performance may result from exercise-induced attentional control observed during frontal neural excitation. [ABSTRACT FROM AUTHOR]

Although mentally fatiguing cognitive tasks can impair subsequent physical endurance, the importance of cognitive task duration and the role of response inhibition remain unclear. This study compared the effects of a serial incongruent Stroop color-classification task (i.e., with response inhibition) and N-back memory updating task (i.e., without response inhibition) on mental fatigue and subsequent rhythmic handgrip exercise. Participants (N = 90) were randomly assigned to one of three cognitive task groups (Stroop, 2-back, control) and completed four 10-min blocks of one cognitive task followed by a 5-min physical endurance task (self-paced rhythmic handgrip exercise). Heart rate, heart rate variability, electromyographic forearm activity, and force were recorded throughout along with self-reported measures of fatigue, exertion, and motivation. From the start, the Stroop and 2-back tasks elicited higher heart rate and lower heart rate variability as well as greater fatigue, effort, and interest/enjoyment than the control task. From the second block onwards, the Stroop and 2-back groups produced less force than the control group. There were no group differences in forearm muscle activity. In sum, mental fatigue was induced after performing a cognitive task for 10 mins, whereas muscular endurance was impaired after performing a cognitive task for 20 mins. That these effects were observed for both types of cognitive task indicates that response inhibition is not a necessary condition. The cognitive task duration required to induce mental fatigue and impair rhythmic handgrip endurance performance lay between the durations reported previously for isometric (a few minutes) and whole-body (half an hour) endurance exercise., (© 2022 The Authors. Psychophysiology published by Wiley Periodicals LLC on behalf of Society for Psychophysiological Research.)

Understanding central fatigue during motor activities is important in neuroscience and different medical fields. The central mechanisms of motor fatigue are known in depth for isometric muscle contractions; however, current knowledge about rhythmic movements and central fatigue is rather scarce. In this study, we explored the role of an executive area (left dorsolateral prefrontal cortex [DLPFC]) in fatigue development during rhythmic movement execution, finger tapping (FT) at the maximal rate, and fatigue after effects on the stability of rhythmic patterns. Participants (n = 19) performed six sets of unresisted FT (with a 3 min rest in-between). Each set included four interleaved 30 s repetitions of self-selected (two repetitions) and maximal rate FT (two repetitions) without rest in-between. Left DLPFC involvement in the task was perturbed by transcranial static magnetic stimulation (tSMS) in two sessions (one real and one sham). Moreover, half of the self-selected FT repetitions were performed concurrently with a demanding cognitive task, the Stroop test. Compared with sham stimulation, real tSMS stimulation prevented waning in tapping frequency at the maximal rate without affecting perceived levels of fatigue. Participants' engagement in the Stroop test just prior to maximal FT reduced the movement amplitude during this mode of execution. Movement variability at self-selected rates increased during Stroop execution, especially under fatigue previously induced by maximal FT. Our results indicate cognitive-motor interactions and a prominent role of the prefrontal cortex in fatigue and the motor control of simple repetitive movement patterns. We suggest the need to approach motor fatigue including cognitive perspectives., (© 2022 The Authors. Psychophysiology published by Wiley Periodicals LLC on behalf of Society for Psychophysiological Research.)

Studies of the Stroop color-word task have provided evidence for the existence of two conflicts: (1) an early task conflict between noting the relevant color and reading afforded by the irrelevant word (or word-like stimuli), and (2) a late information conflict between the information provided by the word and the information provided by the color. Measurements of pupil changes, in addition to reaction time (RT), have extended understanding regarding these two conflicts. The current work examines the generalizability of such understanding. We ask whether similar processes work in the comparative judgment of numbers (e.g., in the numerical Stroop task). We present two experiments that support and extend the knowledge gained in the word-color context to numerical processing. Similar to results with the Stroop color-word task, we found a dissociation between RT and pupillometry and an early task conflict followed by an information conflict., (© 2022 The Authors. Psychophysiology published by Wiley Periodicals LLC on behalf of Society for Psychophysiological Research.)

Frontal-midline (FM) theta activity (4-8 Hz) is proposed to reflect a mechanism for cognitive control that is needed for working memory retention, manipulation, and interference resolution. Modulation of FM theta activity via neurofeedback training (NFT) demonstrated transfer to some but not all types of cognitive control. Therefore, the present study investigated whether FM theta NFT enhances performance and modulates underlying EEG characteristics in a delayed match to sample (DMTS) task requiring mainly proactive control and a color Stroop task requiring mainly reactive control. Moreover, temporal characteristics of transfer were explored over two posttests. Across seven 30-min NFT sessions, an FM theta training group exhibited a larger FM theta increase compared to an active control group who upregulated randomly chosen frequency bands. In a posttest performed 13 days after the last training session, the training group showed better retention performance in the DMTS task. Furthermore, manipulation performance was associated with NFT theta increase for the training but not the control group. Contrarily, behavioral group differences and their relation to FM theta change were not significant in the Stroop task, suggesting that NFT is associated with proactive but not reactive control enhancement. Transfer to both tasks at a posttest one day after training was not significant. Behavioral improvements were not accompanied by changes in FM theta activity, indicating no training-induced modulation of EEG characteristics. Together, these findings suggest that NFT supports transfer to cognitive control that manifests late after training but that other training-unspecific factors may also contribute to performance enhancement., (© 2021 The Authors. Psychophysiology published by Wiley Periodicals LLC on behalf of Society for Psychophysiological Research.)

Canonical correlation was used to investigate the interrelationships between somatic, biochemical, and psychological variables in 40 healthy male subjects. Four roots (or factors) were extracted which demonstrated overlap in four sets of variables: 1) Somatic (height, weight, body volume, body surface area); 2) Biochemical (adrenal steroids, pepsinogen, creatinine, urine volume); 3) Perceptual (Embedded Faces, Stroop Test, Time Estimation, Flicker Fusion); and 4) Rorschach indices. The first root linked style of spatial orientation with height. The second factor extracted major loadings for all sets of variables and was dominated by big body size, high and variable biochemical values, and low perceptual control. The final factors were less well defined. Genetic or constitutional forces could be inferred and the interaction of personality, biochemical, and somatic variables was clearly demonstrated. [ABSTRACT FROM AUTHOR]

This study explored differences in sustained top-down attentional control (i.e., proactive control) and spontaneous types of control (i.e., reactive control) in bilingual and monolingual speakers. We modified a Color-Word Stroop task to varying levels of conflict and included switching trials in addition to more "traditional" inhibition Stroop conditions. The task was administered during scalp electroencephalography (EEG) to evaluate the temporal course of cognitive control during trials. The behavioral Stroop effect was observed across the whole sample; however, there were no differences in accuracy or response time between the bilingual and monolingual groups. Event-related potentials (ERPs) were calculated for the N200, N450, and conflict Sustained Potential (SP). On the pure-blocked incongruent trials, the bilingual group displayed reduced signal during interference suppression (N450) and increased later signal, as indexed by the conflict SP. On the mixed-block incongruent trials, both the bilinguals and monolinguals displayed increased later signal at the conflict SP. This suggests that proactive control may be a default mode for bilinguals on tasks requiring inhibition. In the switching trials, that place high demands on the executive control component of shifting, the language groups did not differ. Overall, these results suggest processing differences between bilinguals and monolinguals extend beyond early response inhibition processes. Greater integration of proactive and reactive control may be needed to sort conflicting language environments for bilinguals, which may be transferring to domain-general mechanisms., (© 2021 Society for Psychophysiological Research.)

Alexithymia has been associated with emotion recognition deficits in both auditory and visual domains. Although emotions are inherently multimodal in daily life, little is known regarding abnormalities of emotional multisensory integration (eMSI) in relation to alexithymia. Here, we employed an emotional Stroop-like audiovisual task while recording event-related potentials (ERPs) in individuals with high alexithymia levels (HA) and low alexithymia levels (LA). During the task, participants had to indicate whether a voice was spoken in a sad or angry prosody while ignoring the simultaneously presented static face which could be either emotionally congruent or incongruent to the human voice. We found that HA performed worse and showed higher P2 amplitudes than LA independent of emotion congruency. Furthermore, difficulties in identifying and describing feelings were positively correlated with the P2 component, and P2 correlated negatively with behavioral performance. Bayesian statistics showed no group differences in eMSI and classical integration-related ERP components (N1 and N2). Although individuals with alexithymia indeed showed deficits in auditory emotion recognition as indexed by decreased performance and higher P2 amplitudes, the present findings suggest an intact capacity to integrate emotional information from multiple channels in alexithymia. Our work provides valuable insights into the relationship between alexithymia and neuropsychological mechanisms of emotional multisensory integration., (© 2021 The Authors. Psychophysiology published by Wiley Periodicals LLC on behalf of Society for Psychophysiological Research.)

When comparing the digits of different physical sizes, the processing of numerical value interacts with the processing of physical size. Given the universal use of Arabic numbers in mathematics and daily life, this study aims to elucidate the cognitive processes involved in the interactions of task-relevant and task-irrelevant features during information processing. We investigated this question by examining event-related potential (ERP) using a modified version of the size congruity comparison, which is a Stroop-like task. Numerical value and physical size were varied independently under task-relevant and task-irrelevant conditions. To better examine how the task-irrelevant features modulated the processing of the task-relevant attributes, a neutral condition was included in both tasks. For the physical task, congruent trials showed a less negative N200 response than neutral trials (indicating a facilitation effect), and incongruent trials elicited a larger N450 and smaller late positive complex (LPC) response than neutral trials (indicating an interference effect). For the numerical task, congruent trials showed a larger LPC response than neutral trials (indicating a facilitation effect). These ERP findings indicate that the sources of the facilitation and interference effects appear in different cognitive processes for each task. We further suggest that language characteristics may be a factor in the superior numerical processing exhibited in this study., (© 2020 Society for Psychophysiological Research.)

Previous research has revealed that a supine body posture, as compared to a sitting upright posture, decreases approach motivation and cognitive dissonance reduction. The present research was designed to test whether a supine body posture would decrease cognitive conflict processing, the process that occurs prior to cognitive dissonance reduction. Previous research using the Stroop task has found event-related potentials (N450, error-related negativity [ERN]) that are associated with cognitive conflict processing. In the current experiment, participants (N = 35) completed a color-naming Stroop task while sitting upright or supine (within-subjects, counterbalanced). Results revealed that as compared to the upright posture, the supine posture reduced the N450 Stroop interference effect but not the ERN., (© 2020 Society for Psychophysiological Research.)

Alterations in our environment require us to learn or alter motor skills to remain efficient. Also, damage or injury may require the relearning of motor skills. Two types have been identified: movement adaptation and motor sequence learning. Doyonet al. (2003, Distinct contribution of the cortico-striatal and cortico-cerebellar systems to motor skill learning. Neuropsychologia, 41(3), 252-262) proposed a model to explain the neural mechanisms related to adaptation (cortico-cerebellar) and motor sequence learning (cortico-striatum) tasks. We hypothesized that medial frontal negativities (MFNs), event-related electrocortical responses including the error-related negativity (ERN) and correct-response-related negativity (CRN), would be trait biomarkers for skill in motor sequence learning due to their relationship with striatal neural generators in a network involving the anterior cingulate and possibly the supplementary motor area. We examined 36 participants' improvement in a motor adaptation and a motor sequence learning task and measured MFNs elicited in a separate Spatial Stroop (conflict) task. We found both ERN and CRN strongly predicted performance improvement in the sequential motor task but not in the adaptation task, supporting this aspect of the Doyon model. Interestingly, the CRN accounted for additional unique variance over the variance shared with the ERN suggesting an expansion of the model., (© 2020 The Authors. Psychophysiology published by Wiley Periodicals LLC on behalf of Society for Psychophysiological Research.)

The relationship of physical activity with interference processing was examined using behavioral and neuroelectrical measures in young adults divided into more active and less active groups. The participants completed Stroop (i.e., color-naming) and reverse Stroop (i.e., word-meaning) tasks that differed in the level of difficulty while event-related potentials were assessed. In the low interference Stroop task, participants were asked to respond to the ink color of the word, while the meaning was either congruent or incongruent with the color. In the high interference reverse Stroop task, participants had to indicate the meaning of colored words while ignoring the color of the font. The results indicated that young adults in the more active group exhibited a shorter response time (RT) and a lower intra-individual variability of RT than did those in the less active group. These behavioral differences were associated with larger P2 and P3 and smaller N450 amplitudes in the Stroop task and with larger P2 and N2 and smaller N450 amplitudes in the reverse Stroop task. No differences were observed in the contingent negative variation (CNV) between the groups. These findings suggest that, for young adults, regular physical activity is positively associated with a better neural efficiency in resource allocation for tasks that require the ability to inhibit cognitive interference and provide evidence for the potential neural mechanisms underlying the improved Stroop performance., (© 2020 Society for Psychophysiological Research.)

Error processing is critical for adaptive behaviors. Acute stress has been found to influence error processing. However, the neural dynamic correlates underlying this modulation remain elusive. To address this issue, we recruited 39 healthy male participants, who performed a two-session task before and after an acute stress test while their behavioral and EEG data were recorded. The participants were randomly exposed to either a stress condition (Maastricht Acute Stress Test) or a control condition. The stress test consisted of several hand immersion tasks (ice-cold water, 2°C) and mental arithmetic tasks. A color-word Stroop task was used to investigate the stress effect on error responses. Based on the level of stress-induced cortisol, the participants in the stress group were further classified as low (N = 13) or high (N = 13) cortisol responders. The results indicated that only in the high cortisol responders, the error-related negativity (ERN) amplitude was reduced after acute stress. In addition, the ∆ERN in the high cortisol responders was significantly smaller than that in the low cortisol responders. These results suggest that acute stress impairs error detection. However, the error positivity amplitudes increased in the stress group compared to the control group, indicating that acute stress leads to greater error assessment. Taken together, these results suggest that acute stress impairs error detection, which is modulated by individuals' response level following acute stress, and leads to more emotional and/or motivational responses to the error signal once the error is consciously realized., (© 2019 Society for Psychophysiological Research.)