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Traditional conflict-based cognitive assessment tools are highly behaviorally restrictive, which prevents them from capturing the dynamic nature of human cognition, such as the tendency to make error-correcting responses. The cognitive game Tunnel Runner measures interference control, response inhibition, and response-rule switching in a less restrictive manner than traditional cognitive assessment tools by giving players movement control after an initial response and encouraging error-correcting responses. Nevertheless, error-correcting responses remain unused due to a limited understanding of what they measure and how to use them. To facilitate the use of error-correcting responses to measure and understand human cognition, we developed theoretically-grounded measures of error-correcting responses in Tunnel Runner and assessed whether they reflected the same cognitive functions measured via initial responses. Furthermore, we evaluated the measurement potential of error-correcting responses. We found that initial and error-correcting responses similarly reflected players' response inhibition and interference control, but not their response-rule switching. Furthermore, combining the two response types increased the reliability of interference control and response inhibition measurements. Lastly, error-correcting responses showed the potential to measure response inhibition on their own. Our results pave the way toward understanding and using post-decision change of mind data for cognitive measurement and other research and application contexts., (© 2024. The Author(s).)

Dynamic cognitive psychometrics measures mental capacities based on the way behavior unfolds over time. It does so using models of psychological processes whose validity is grounded in research from experimental psychology and the neurosciences. However, these models can sometimes have undesirable measurement properties. We propose a "hybrid" modeling approach that achieves good measurement by blending process-based and descriptive components. We demonstrate the utility of this approach in the stop-signal paradigm, in which participants make a series of speeded choices, but occasionally are required to withhold their response when a "stop signal" occurs. The stop-signal paradigm is widely used to measure response inhibition based on a modeling framework that assumes a race between processes triggered by the choice and the stop stimuli. However, the key index of inhibition, the latency of the stop process (i.e., stop-signal reaction time), is not directly observable, and is poorly estimated when the choice and the stop runners are both modeled by psychologically realistic evidence-accumulation processes. We show that using a descriptive account of the stop process, while retaining a realistic account of the choice process, simultaneously enables good measurement of both stop-signal reaction time and the psychological factors that determine choice behavior. We show that this approach, when combined with hierarchical Bayesian estimation, is effective even in a complex choice task that requires participants to perform only a relatively modest number of test trials., (© 2024. The Author(s).)

The use of go/no-go tasks to assess inhibitory control over food stimuli is becoming increasingly popular. However, the wide variability in the design of these tasks makes it difficult to fully leverage their results. The goal of this commentary was to provide researchers with crucial aspects to consider when designing food-related go/no-go experiments. We examined 76 studies that used food-themed go/no-go tasks and extracted characteristics related to participant population, methodology, and analysis. Based on our observations of common issues that can influence study conclusions, we stress the importance for researchers to design an appropriate control condition and match stimuli between experimental conditions in terms of emotional and physical properties. We also emphasize that stimuli should be tailored to the participants under study, whether at the individual or group level. To ensure that the task truly measures inhibitory abilities, researchers should promote the establishment of a prepotent response pattern by presenting more go than no-go trials and by using short trials. Researchers should also pre-specify the criteria used to identify potentially invalid data. While go/no-go tasks represent valuable tools for studying food cognition, researchers should choose task parameters carefully and justify their methodological and analytical decisions in order to ensure the validity of results and promote best practices in food-related inhibition research., Competing Interests: Declaration of competing interest The authors have no conflict of interest to declare., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Theories of affective influences on cognition posit that negative mood may increase cognitive load, causing a decrement in task performance (Seibert & Ellis, [1991]. Irrelevant thoughts, emotional mood states, and cognitive task performance. Memory & Cognition , 19 (5), 507-513), or cause a shift to more analytic thinking, which benefits tasks requiring attention to detail (Schwarz & Clore, [1983]. Mood, misattribution, and judgments of well-being: Informative and directive functions of affective states. Journal of Personality and Social Psychology , 45 (3), 513-523). We previously reported that individuals who are higher in the trait of emotional reactivity performed better on an inhibitory task with increasing negative mood whereas low-reactive individuals showed the converse pattern (Gabel & McAuley, [2018]. Does mood help or hinder executive functions? Reactivity may be the key. Personality and Individual Differences , 128 , 94-99; [2020]. React to act: Negative mood, response inhibition, and the moderating role of emotional reactivity. Motivation and Emotion , 44 (6), 862-869). Because high-reactive individuals are more accustomed to negative affect (Nock et al., [2008]. The emotion reactivity scale: Development, evaluation, and relation to self-injurious thoughts and behaviors. Behavior Therapy , 39 (2), 107-116), we speculated that negative mood engendered analytic thinking but without a task-incongruent increase in cognitive load - thereby facilitating performance. Here, we induced a heuristic or analytic approach to information processing prior to performance of an inhibitory task and expected different results pending the thinking style induced. In the heuristic condition, increasing negative mood was associated with better performance for high-reactive participants but not their low-reactive counterparts. In the analytic condition, increasing negative mood was associated with better performance irrespective of emotional reactivity. Our results are consistent with the notion that negative mood engenders analytic thinking which may benefit response inhibition provided it does not increase task-incongruent cognitive load.

Previous work has demonstrated a link between cognitive abilities, specifically inhibitory control and lethal force decision-making performance. However, many previously used approaches to simulating shoot/don't shoot scenarios have lacked ecological validity. There is a need to investigate how inhibitory control impacts shoot/don't decisions using realistic simulations to better translate the findings to military and law enforcement settings. This study used multiple cognitive control tasks incorporating discrete judgements in go/no-go and stop signal tasks as well as subjective judgements in go/no-go tasks with both colour stimuli and emotional faces. These combined tasks provided a comprehensive evaluation of inhibitory control abilities. To ensure ecological validity in shooting performance, existing military training scenarios incorporated realistic weaponry and aiming behaviours across different shoot/don't-shoot simulations. The inhibitory control battery identified five principal components from the various tasks, including: stopping ability, response speed, emotion detection, colour detection, and emotional biases. These principal inhibitory control components were entered into hierarchical linear regressions with the dependent variables of unintended casualties inflicted and lethal rounds fired, respectively. Stopping ability better predicted the likelihood of inflicting an unintended casualty, whereas response speed better predicted the number of lethal rounds fired. These regression models included baseline metrics of marksmanship and shots fired, which supports a role for inhibitory control above and beyond basic shooting abilities or strategy. These collective findings provide mechanistic support for the relationship between inhibitory control and errors in shoot/don't-shoot decision-making while using realistic military training scenarios.

Parkinson's disease (PD) impairs various cognitive functions, including time perception. Dysfunctional time perception in PD is poorly understood, and no study has investigated the rehabilitation of time perception in patients with PD. We aimed to induce the recovery of time perception in PD patients and investigated the potential relationship between recovery and cognitive functions/domains other than time perception. Sixty patients with PD (27 females) and 20 healthy controls (10 females) were recruited. The participants underwent a feedback training protocol for 4 weeks to improve the accuracy of subjective spatial distance or time duration using a ruler or stopwatch, respectively. They participated in three tests at weekly intervals, each comprising 10 types of cognitive tasks and assessments. After duration feedback training for 1 month, performance on the Go/No-go task, Stroop task, and impulsivity assessment improved in patients with PD, while no effect was observed after distance feedback training. Additionally, the effect of training on duration production correlated with extended reaction time and improved accuracy in the Go/No-go and Stroop tasks. These findings suggest that time perception is functionally linked to inhibitory systems. If the feedback training protocol can modulate and maintain time perception, it may improve various cognitive/psychiatric functions in patients with PD. It may also be useful in the treatment of diseases other than PD that cause dysfunctions in temporal processing., (© 2021 Wiley Periodicals LLC.)

Flexible initiation or suppression of actions to avoid aversive events is crucial for survival. The prelimbic (PL) and infralimbic (IL) regions of the medial prefrontal cortex (mPFC) have been implicated in different aspects of avoidance and reward-seeking, but their respective contribution in instigating versus suppressing actions in aversive contexts remains to be clarified. We examined mPFC involvement in different forms of avoidance in rats well trained on different cued lever-press avoidance tasks. Active/inhibitory avoidance required flexible discrimination between auditory cues signaling foot-shock could be avoided by making or withholding instrumental responses. On a simpler active avoidance task, a single cue signaled when a lever press would avoid shock. PL inactivation disrupted active but not inhibitory avoidance on the discriminative task while having no effect on single-cued avoidance. In comparison, IL inactivation broadly impaired active and inhibitory avoidance. Conversely, on a cued appetitive go/no-go task, both IL and PL inactivation impaired inhibitory but not active reward-seeking, the latter effect being diametrically opposite to that observed on the avoidance task. These findings highlight the complex manner in which different mPFC regions aid in initiating or inhibiting actions in the service of avoiding aversive outcomes or obtaining rewarding ones. IL facilitates active avoidance but suppress inappropriate actions in appetitive and aversive contexts. In contrast, contextual valence plays a critical role in how the PL is recruited in initiating or suppressing actions, which may relate to the degree of cognitive control required to flexibly negotiate response or motivational conflicts and override prepotent behaviors. SIGNIFICANCE STATEMENT Choosing to make or withhold actions in a context-appropriate manner to avoid aversive events or obtain other goals is a critical survival skill. Different medial prefrontal cortex (mPFC) regions have been implicated in certain aspects of avoidance, but their contributions to instigating or suppressing actions remains to be clarified. Here, we show that the dorsal, prelimbic (PL) region of the medial PFC aids active avoidance in situations requiring flexible mitigation of response conflicts, but also aids in withholding responses to obtain rewards. In comparison the ventral infralimbic (IL) cortex plays a broader role in active and inhibitory avoidance as well as suppressing actions to obtain rewards. These findings provide insight into mechanisms underlying normal and maladaptive avoidance behaviors and response inhibition., (Copyright © 2020 the authors.)

This study aims to bridge the gap between the discrepant views of existing studies in different modalities on the cognitive effect of video game play. To this end, we conducted a set of tests with different modalities within each participant: (1) Self-Reports Analyses (SRA) consisting of five popular self-report surveys, and (2) a standard Behavioral Experiment (BE) using pro- and antisaccade paradigms, and analyzed how their results vary between Video Game Player (VGP) and Non-Video Game Player (NVGP) participant groups. Our result showed that (1) VGP scored significantly lower in Behavioral Inhibition System (BIS) than NVGP ( p = 0.023), and (2) VGP showed significantly higher antisaccade error rate than NVGP ( p = 0.005), suggesting that results of both SRA and BE support the existing view that video game play has a maleficent impact on the cognition by increasing impulsivity. However, the following correlation analysis on the results across individual participants found no significant correlation between SRA and BE, indicating a complex nature of the cognitive effect of video game play.

This study examined interactions between cognitive control and emotional processing throughout adolescent development. In particular, we investigated whether age differences in response inhibition and initiation were influenced by an emotional expression of faces and whether the effects differed from processing of nonemotional features of faces. Therefore, we applied two versions of a Go/No-go task, an emotional task requiring responding or withholding responding to happy and angry faces, and a gender task including decisions to female and male faces in a large sample (N = 187, age range = 9-18 years). Considering theoretical assumptions of dual-system models that mid-adolescents are more susceptible to the processing of emotional contents, we expected more inefficient response inhibition on happy and angry trials than on neutral trials. We also expected that these effects would be specific to emotional contents. Results indicated that both response inhibition and initiation showed linear improvements with increasing age. Response inhibition was hampered in the presence of happy and angry faces, especially in mid-adolescents and late adolescents. In contrast, response initiation was highly facilitated to happy faces, indicating a happy effect, leading to more accurate responding in all age groups and to faster responding especially in late adolescents. Children, in contrast to late adolescents, were more accurate in response inhibition and initiation when the gender was task relevant. Results are in line with dual-system models, assuming a higher sensitivity to emotional features from mid-adolescents onward but not to other features such as gender., (Copyright © 2020 Elsevier Inc. All rights reserved.)

It is widely accepted that task-irrelevant threats utilize processing resources, resulting in impaired cognitive processes. However, if some subcomponents of the cognitive processes are activated by a threat, these cognitive processes may be facilitated. In the present study, we investigated whether task-irrelevant threats enhance cognitive control if the threat and task-relevant processes commonly recruit a cognitive process, inhibitory process. To examine the impact of task-irrelevant threats on inhibitory control, we had participants perform a stop-signal task with mild electric shocks. They were at risk for receiving the shocks randomly in threat blocks while no such shock was administered in safe blocks. The results showed that the stop-signal reaction time decreased under threat compared to safe conditions, indicating that inhibitory control was enhanced under threat. This beneficial effect of threat on response inhibition was more evident in participants with high state anxiety. An additional measurement of motor execution indicated that the interaction between threat and response inhibition was not derived from general arousal under threat. Results suggest that emotion and cognition do not interact simply by sharing processing resources but are related more closely to each other than we have previously thought by engaging a common processing., (Copyright © 2019 Elsevier B.V. All rights reserved.)

This study investigated cognitive, neural and endocrine function during late pregnancy. One of the first to examine brain ERPs in pregnant women, the study is unique in its focus on response inhibition function. In the study, cognitive function was evaluated by a digit-symbol coding test, an arithmetic ability test, and a visual stop-signal task which places enhanced demands on impulse control and response inhibition, considered a hallmark of executive function. Brain activity was measured by scalp-recorded Event-Related Potentials (ERPs) during the stop-signal task. HPA axis reactivity was assessed by measuring salivary cortisol levels before and after experimental sessions. Test performance, ERPs and cortisol reactivity were compared across groups of 23 women in their third trimester of pregnancy and 22 non-pregnant controls. Pregnant women scored lower than the control group on the digit-symbol coding test. On the stop-signal task, both groups had similar error rates, but pregnant women had longer response times to Go trials. On the Stop condition of the task in which a response must be inhibited, pregnant women demonstrated significantly better performance. At the electrophysiological level, in response to Go stimuli pregnant women exhibited greater amplitude of P2 than controls. In response to Stop-signals, pregnant women had lesser amplitudes of P1 and N2 and greater amplitude of P3. Cortisol reactivity to the test session was significantly more pronounced in non-pregnant women with significant correlations found between cortisol reactivity and behavioral responses. The results suggest that response patterns of women in late pregnancy are less impulsive and more cautious and controlled., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Existing research suggests that inhibitory control deficits may differentiate individuals who think about suicide from those who make a suicide attempt. However, no available research, to our knowledge, has examined whether suicidal behaviors are associated with disruptions in the ability to determine when inhibitory control is needed or the ability to engage inhibition of an inappropriate or maladaptive behavior. The current study utilized event-related potentials to investigate specific facets of inhibitory control and their associations with suicide attempt history among a heterogeneous clinical sample who reported current suicidal ideation., Methods: Ideators with no past suicide attempts (n = 46) and those with a history of suicide attempts (n = 22) completed a complex go/no-go task. Raw waveforms and temporospatial principal components analysis were used to index conflict detection (i.e., ΔN2) and motor inhibition (i.e., ΔP3a). Behavioral performance indices were also examined., Results: Suicide attempters exhibited deficits in detecting the need for inhibitory control, as indexed by a more positive ΔN2 factor, than did ideating nonattempters, even when accounting for psychiatric comorbidity and age. However, these results only emerged in the principal components analysis-derived latent factor. No differences in behavioral performance or ΔP3a amplitude emerged., Conclusions: A relative inability to detect when to inhibit a maladaptive behavior, but not the ability to engage motor inhibition to stop that behavior, may distinguish suicide ideators who make a suicide attempt from those who do not. However, future research with prospective designs are needed to determine how conflict detection deficits may contribute to the emergence or escalation of a suicidal crisis., (Copyright © 2019 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)

This study explored whether reduction of the maximal voluntary force of finger flexor muscles affects response inhibition processing while performing the flanker "inhibitory reaction time" task. Sixteen participants completed two experimental sessions: each consisted of either a fatiguing exercise (fatigue session) or a control task (control session) followed by a flanker task. When responding to 32 compatible and 32 incompatible trials, the participants were asked to respond to a right-facing arrow by pressing a button beneath their middle finger, and to a left-facing arrow by pressing a button beneath their index finger. During the fatigue session, the participants were instructed to sustain 50% of their maximal voluntary isometric force during a handgrip force task with their wrist in a neutral position. In the control session, this exercise was replaced by a 7-min period of rest. The results showed that the handgrip task was effective at inducing a significant decrease in maximal force (-25.2 ± 9.1%, p < 0.001). However, this performance fatigability did not affect either the reaction time or the error rate. Similarly, it did not alter the conflict-monitoring function involved in the settings of response override. A functional robustness of the inhibition function under fatigue effect is assumed, at least in young healthy adults., (Copyright © 2018 Elsevier B.V. and Japan Neuroscience Society. All rights reserved.)

Inhibitory control matures through adolescence and into early adulthood, impacting decision-making. Impairments in inhibitory control are associated with various psychopathologies, many of which emerge during adolescence. In this review, we examine the neural basis of developmental improvements in inhibitory control by integrating findings from humans and non-human primates, identifying the structural and functional specialization of executive brain systems that mediates cognitive maturation. Behavioral manifestations of response inhibition suggest that adolescents are capable of producing adult level responses on occasion, but lack the ability to engage systems mediating response inhibition in a consistent fashion. Maturation is associated with changes in structural anatomy as well as local and systems-level connectivity. Functional changes revealed by neuroimaging and neurophysiology indicate that maturation of inhibitory control is achieved through improvements in response preparation, error processing, and planned responses., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

We investigated neural correlates of cognitive function in adults with beta thalassaemia major (β-TM) compared to healthy controls using scalp-recorded event-related potentials (ERPs). Event-related potential studies in the field of β-TM are scarce and mostly limited to children. A stop-signal task was used to evaluate indices of attention and response inhibition function, considered to be the hallmark of executive control. Correlations between task performance, ERPs and haemoglobin were also examined. Results showed impaired cognitive performance in β-TM patients, as indicated by longer response times than controls. Haemoglobin was negatively correlated with response times to Go stimuli. Electrophysiological results indicated significant β-TM-related alterations in neuronal activity, reflected in greater peak amplitudes of several task-related ERP components. A possible interpretation of these ERP results is that β-TM patients need to recruit additional brain resources when dealing with cognitive challenge. Significant correlations were found between levels of haemoglobin and amplitude of all ERP components; the lower the haemoglobin, the more pronounced the ERPs amplitude. The present study represents a novel investigation of cognitive function and related brain dynamics in β-TM in adult. Integrating neuropsychological assessment and interventions into traditional disease management, may be imperative in achieving a better quality of life for these patients., (© 2019 British Society for Haematology and John Wiley & Sons Ltd.)

Study Objectives: Although sleep deprivation has long been known to negatively affect cognitive performance, the exact mechanisms through which it acts and what cognitive domains are affected most is still disputed. The current study provides a theory-driven approach to examine and explain the detrimental effects of sleep loss with a focus on attention and cognitive control., Methods: Twenty-four participants (12 females; age: 24 ± 3 years) completed the experiment that involved laboratory-controlled over-night sleep deprivation and two control conditions, namely, a normally rested night at home and a night of sleep in the laboratory. Using a stop signal task in combination with electroencephalographic recordings, we dissociated different processes contributing to task performance such as sustained attention, automatic or bottom-up processing, and strategic or top-down control. At the behavioral level, we extracted reaction times, response accuracy, and markers of behavioral adjustments (post-error and post-stop slowing), whereas at the neural level event-related potentials (ERP) found in context of response inhibition (N2/P3) and error monitoring (ERN/Pe) were obtained., Results: It was found that 24 hr of sleep deprivation resulted in declined sustained attention and reduced P300 and Pe amplitudes, demonstrating a gradual breakdown of top-down control. In contrast, N200 and ERN as well as the stop-signal reaction time showed higher resilience to sleep loss signifying the role of automatic processing., Conclusions: These results support the notion that sleep deprivation is more detrimental to cognitive functions that are relatively more dependent on mental effort and/or cognitive capacity, as opposed to more automatic control processes., (© Sleep Research Society 2019. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.)

Background: This study sought to identify attention-deficit/hyperactivity disorder (ADHD) abnormalities in relationships between brain white matter structure and individual differences in several types of impulsive behavior., Methods: Adolescents, n = 67 with ADHD combined subtype and n = 68 without ADHD, were given neuropsychological tests and underwent diffusion tensor imaging scans. Principal component analysis reduced test scores into factors representing different types of impulsive behavior. Tract-based spatial statistics quantified white matter integrity in relationship to components of impulsive behavior. ADHD versus non-ADHD differences in the strength and nature of linear relationships between regional white matter and three impulsivity components were examined using multiple regression., Results: Principal component analysis found three separate impulsivity-related factors that were interpreted as motor response inhibition, impulsive choice, and delay aversion. Relationships between regional fractional anisotropy and response inhibition or impulsive choice did not differ between ADHD and non-ADHD groups. There was a significant interaction between diagnostic group and delay aversion test performance relationships with regional fractional anisotropy. For youths without ADHD, greater anisotropy in numerous tracts predicted better delay aversion test performance. In contrast, anisotropy in regions including the corpus callosum, corona radiata, internal capsule, and corticospinal tracts had either a negative or no relationship with delay aversion test performance in ADHD., Conclusions: The results provide additional support that different proposed etiological pathways to ADHD have discretely different neurobiological features. Large disorganization of white matter microstructure appears to contribute to reward-based ADHD pathways rather than motor inhibition., (Copyright © 2018 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)

Individual differences in cognitive function are due to a combination of heritable and non-heritable factors. A large body of evidence from clinical, cognitive, and pharmacological neuroscience implicates dopaminergic gene variants as modulators of cognitive functions. Neuroepigenetic studies demonstrate environmental factors also influence complex phenotypes by affecting gene expression regulation. To evaluate the mechanism of environmental influence on cognitive abilities, we examined if epigenetic regulation of dopaminergic genes plays a role in cognition. Using a DNA methylation profiling microarray, we used a monozygotic (MZ) twin difference design to evaluate if co-twin differences in methylation of CpG sites near six dopaminergic genes predicted differences in response inhibition and memory performance. Studying MZ twins allows us to assess if environmentally driven differences in methylation affect differences in phenotype while controlling for the influence of genotype and shared family environment. Response inhibition was assessed with the flanker task and short-term and working memory were assessed with digit span recall. We found MZ co-twin differences in DRD4 gene methylation predicted differences in short-term memory. MZ differences in COMT, DBH, DAT1, DRD1, and DRD2 gene methylation predicted differences in response inhibition. Taken together, findings suggest methylation status of dopaminergic genes may influence cognitive functions in a dissociable manner. Our results highlight the importance of the epigenome and environment, over and above the influence of genotype, in supporting complex cognitive functions.

The Salience Network (SN) and its interactions are important for cognitive control. We have previously shown that structural damage to the SN is associated with abnormal functional connectivity between the SN and Default Mode Network (DMN), abnormal DMN deactivation, and impaired response inhibition, which is an important aspect of cognitive control. This suggests that stimulating the SN might enhance cognitive control. Here, we tested whether non-invasive transcranial direct current stimulation (TDCS) could be used to modulate activity within the SN and enhance cognitive control. TDCS was applied to the right inferior frontal gyrus/anterior insula cortex during performance of the Stop Signal Task (SST) and concurrent functional (f)MRI. Anodal TDCS improved response inhibition. Furthermore, stratification of participants based on SN structural connectivity showed that it was an important influence on both behavioural and physiological responses to anodal TDCS. Participants with high fractional anisotropy within the SN showed improved SST performance and increased activation of the SN with anodal TDCS, whilst those with low fractional anisotropy within the SN did not. Cathodal stimulation of the SN produced activation of the right caudate, an effect which was not modulated by SN structural connectivity. Our results show that stimulation targeted to the SN can improve response inhibition, supporting the causal influence of this network on cognitive control and confirming it as a target to produce cognitive enhancement. Our results also highlight the importance of structural connectivity as a modulator of network to TDCS, which should guide the design and interpretation of future stimulation studies., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

During the last decade, the ontogeny of tool making has received growing attention in the literature on tool-related behaviors. However, the cognitive demands underlying tool making are still not clearly understood. In this cross-sectional study of 52 Turkish preschool children from 3 to 6 years of age, the roles of executive function (response inhibition), ability to form hierarchical representations (hierarchical structuring), and social learning were investigated with the hook task previously used with children and animals. In this task, children needed to bend a pipe cleaner to fetch a small bucket with a sticker out of a tall jar. This study replicated earlier findings that preschoolers have great difficulty in tool innovation. However, social learning facilitates tool making, especially after 5 years of age. Capacities to form hierarchical representations and to inhibit prepotent responses were significant positive predictors of tool making after social learning., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Objective: To examine the relationship between extended high-frequency pure tone hearing thresholds (frequencies 10 to 14 kHz) and working memory capacity (WMC), inhibitory control, and cognitive flexibility., Design: Experimental study measuring correlations between different high-frequency hearing threshold measures and cognitive measures., Study: Pure tone audiometry was assessed in the extended high-frequency (frequencies 10, 12.5 and 14 kHz). Subjects were also tested regarding WMC, inhibitory control (response inhibition), and cognitive flexibility (information updating and shifting ability)., Sample: Forty-three subjects between 20 and 29 years old with normal hearing (≤ 20 dB HL) in the frequency range between 0.125 to 8 kHz., Results: No significant correlations were seen between high-frequency hearing thresholds defined as average best and worst ear high-frequency hearing thresholds and the cognitive measures. Differences between the best and the worst ear showed significant negative correlations with inhibitory control and global executive function (combination score for WMC, inhibitory control and cognitive flexibility)., Conclusions: The present study suggests that global executive functions, more specifically response inhibition, and hearing threshold asymmetry in the extended high-frequency range are interrelated.

Background: Impulsivity is a multi-faceted concept. It is a crucial feature of many neuropsychiatric disorders. Three subtypes of impulsivity have been identified: motor, temporal, and cognitive impulsivity. Existing evidence suggests that the right inferior frontal gyrus (rIFG) plays a crucial role in impulsivity, and such a role has been elucidated using inhibitory repetitive transcranial magnetic stimulation (rTMS). There is a dearth of studies using excitatory rTMS at the rIFG, an important gap in the literature this study aimed to address., Methods: Twenty healthy male adults completed a single-blind sham-controlled randomised crossover study aimed at assessing the efficacy of rTMS in the neuromodulation of impulsivity. This involved delivering 10-Hz excitatory rTMS to the rIFG at the intensity of 100% motor threshold with 900 pulses per session. Trait impulsivity was measured at baseline using the Barrett Impulsiveness Scale and UPPS-P Impulsiveness Scale. The Stop Signal Task (SST) and Information Sampling Task (IST), administered before and after rTMS sessions, were used as behavioural measures of impulsivity., Results: No significant changes on any measures from either SST or IST after active rTMS at the rIFG compared to the sham-controlled condition were found., Conclusions: Excitatory rTMS applied to the rIFG did not have a statistically significant effect on response inhibition and reflective/cognitive impulsivity. Further research is required before drawing firm conclusions. This may involve a larger sample of highly impulsive individuals, a different stimulation site or a different TMS modality such as theta burst stimulation., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objective: This study's aim was to investigate the features and neural mechanisms of sustained attention in patients with mild traumatic brain injury (mTBI) by comparing and analyzing neuropsychological, behavioral, event-related potentials, and event-related desynchronization and synchronization between mTBI patients and healthy controls., Methods: Twenty mTBI patients with mTBI and 20 healthy controls underwent the Mini-Mental State Examination (MMSE) and a cued continuous performance task (AX-CPT). Neuropsychological, behavioral, and electroencephalogram (EEG) data were collected and analyzed., Results: There were significant differences between the mTBI group and the control group in their MMSE total scores, attention, and calculation, but there were no significant differences in orientation, memory, recall, and verbal scores. There were significant differences between the mTBI group and the control group in hitting the number, reaction time, and the number of errors of omission, but there were no significant differences in the number of false errors. The amplitude of Go-N2 and Nogo-N2 was significantly smaller for the mTBI group than that for the control group. The amplitude of Go-P3 was significantly smaller for the mTBI group than that for the control group, but not for the amplitude of Nogo-P3. The Go-αERS were significantly less for the mTBI group than for the control group during the 0-200 ms after the stimulus onset. The Go-αERD and Nogo-αERD were significantly less for the mTBI group than for the control group during the 600-1,000 ms after the stimulus onset. The Go-βERS were significantly less for the mTBI group than for the control group during the 200-400 ms after the stimulus onset. There were no significant differences in the Nogo-αERS and Nogo-βERD/ERS between the mTBI group and the control group., Conclusion: Patients with mTBI exhibited impairments in sustained attention and conflict monitoring, while response inhibition may have been spared.

The cortisol awakening response (CAR) is the rapid increase of cortisol levels 30-45 min after awakening in the morning. Numerous studies have indicated the relationship between the CAR and cognition. However, little is known about daily variation in the CAR and cognitive function in healthy adults. The aim of the present study was to investigate whether the CAR predicted the response inhibition function on the same day in both behaviour and the dynamic time course of brain processing. The saliva samples of 47 healthy men were collected at three time points: immediately on awakening, 30 min and 45 min post-awakening in the morning. Participants performed a Go/NoGo task while electroencephalograms (EEG) were recorded in the afternoon of the same day. The results showed that a greater CAR was associated with a stronger N2. In the sub-group of CAR responders (n = 33) the CAR was negatively related to the false alarm rate of NoGo-trials. Our findings suggested that the CAR was predictive of the function of response inhibition in both the earlier cognitive step (i.e., conflict monitoring) and the behavioural performance of response inhibition on the same day in healthy men., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Objective: Deficits in cognitive control are thought to contribute to the maintenance of obesity (OB). Cognitive control is referred to as impulsivity and binge-eating disorder (BED) is characterized by high levels of impulsivity. The present study sought to elucidate which cognitive control functions differentiate between severe OB with and without BED also taking into account hunger as a moderating factor., Method: The study included 48 individuals with OB and BED (OB + BED), 48 individuals with OB and no BED (OB - BED) and 48 normal-weight controls (NWC). Hunger was systematically manipulated: participants were instructed to refrain from eating before testing and received either a liquid meal or flavored water. Then, a comprehensive test battery was administered including a food-related go/no-go task and several subtests from the CANTAB., Results: There were no differences between the groups with regard to food-related response inhibition. However, while manipulating hunger had no impact on performance in the go/no-go task, self-reported hunger significantly influenced task performance by increasing inhibition deficits to high-caloric stimuli in OB + BED. With regard to general cognitive control functions, we found that deficits in attention and impulse control in decision-making distinguished OB from NWC, while reversal learning and risk taking in decision-making appeared to be relevant factors when distinguishing OB + BED from OB - BED., Discussion: Our results indicate that self-reported hunger differentially affected food-related response inhibition. Group differences in general cognitive control functions were limited to attention, reversal learning, and decision-making. Future research needs to account for other possible moderating factors, such as mood, food craving, or stress., (© 2018 Wiley Periodicals, Inc.)

Objective: The study of ADHD uses various computerized tests to assess cognitive functions. Uncertainty exists regarding the association between deficits found by different tools testing similar or different cognitive functions (e.g., continuous performance tests [CPT] and response inhibition [RI] tests).We hypothesized that different tools that measure continuous performance will be better correlated between themselves than with a tool that examines RI., Method: Thirty-six adults with ADHD performed two different CPTs and a RI task. We analyzed correlations between different measures examined by the tasks., Results: There were strong correlations between corresponding measures in the CPTs. Correlations between the results in CPT and the RI task were only minimal., Conclusion: These findings support the specificity of impairments in different cognitive domains (continuous attention vs. RI) beyond the specific test used in the study of ADHD. Also, these findings strengthen the importance of specific discriminative cognitive domains in ADHD.

Understanding the processes that make responses prepotent is central to understanding the role of inhibitory control in cognitive development. The question of what makes responses prepotent was investigated using the two most widely studied measures of preschoolers' inhibitory control. Across two experiments, 80 children were tested either on a series of stimulus-response compatibility (SRC) tasks or on a series of Go/No-go tasks. Results indicated that high levels of prepotency on SRC tasks (such as the Day/Night task) occur only under specific conditions; making a verbal response can be highly prepotent if the stimulus and response are associated with each other (e.g., saying "cup" to a cup) but is less prepotent when they are unassociated (e.g., saying "cup" to a doorstop). Action responses (e.g., lifting a cup to your mouth) show little prepotency irrespective of whether the stimulus and response are associated. In contrast, with Go/No-go tasks, a much wider variety of behaviors are highly prepotent regardless of whether the stimulus and response are associated. These data suggest that prepotency arises in very different ways, depending on the type of task used. Although both Go/No-go tasks and SRC tasks can make inhibitory demands, they do so for fundamentally different reasons., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Converging evidence from studies with animal models and humans suggests that early developmental exposure to polychlorinated biphenyls (PCBs) leads to deficits in cognitive flexibility and inhibitory control. These processes are mediated to a large extent by the prefrontal cortex, thus we examined the effects of PCB exposure during adolescence-a period of robust prefrontal cortical development-on both processes. Specifically, we used operant set-shifting and differential reinforcement of low rates of responding (DRL) tasks to assess cognitive flexibility and response inhibition, respectively. One male and one female pup from each of 14 litters were assigned to each of three treatment groups: 0, 3 or 6mgPCB/kg/day. Rats were dosed orally from postnatal day (PND) 27-50 to capture the whole period of adolescence in rats. At approximately PND 90, they began testing in the set-shifting task which included an initial visual cue discrimination, an extra-dimensional shift to a position discrimination and a reversal of the position discrimination. There were no statistically significant group differences in errors to criterion on visual cue discrimination or on the shift from visual to position discrimination in either males or females. During the position reversal, the 6mg/kg PCB males made significantly fewer errors to reach criterion than control males. The 3mg/kg PCB males showed a trend in the same direction, but this did not reach statistical significance. Interestingly, error analysis revealed that PCB-exposed males made significantly fewer perseverative errors than controls in this phase. No group differences were observed in females. These results suggest a male-specific effect of adolescent PCB-exposure on the reversal phase of the set-shifting task. Following set-shifting, rats progressed to the DRL task in which they were required to withhold responding for a specified period of time (15s) in order to receive a reinforcer. There were no exposure-related group differences in total presses or efficiency ratio in males or in females. In summary, there were subtle sex-specific effects of adolescent PCB exposure on the reversal phase of a set-shifting task, but no effects of exposure on performance on a DRL15 task, suggesting an effect on cognitive flexibility but not response inhibition., (Copyright © 2017 Elsevier Inc. All rights reserved.)

We investigated two components of proactive cognitive control, response facilitation and response inhibition, in an adult lifespan sample (N=544, age range=18-91years) by administering two response-preparation tasks: a procue task, primarily involving facilitation, and an anticue task, involving both facilitation and inhibition. Cues in both tasks corresponded with the index and middle fingers of either the left or right hand. After a random preparation interval (PI) of 100-850ms following the onset of the cue signal, a single-target stimulus indicated the required response. Where procues were spatially aligned with the two fingers of the responding hand, anticues consistently indicated the two fingers of the opposite hand, requiring a remapping of cue location and response hand. This remapping requires inhibition to suppress the automatic activation of the ipsilateral responses. Previous research revealed typical reaction time (RT) profiles for procues and anticues as a function of PI. Whereas procues generate RT benefits (relative to a neutral-cue condition) already at short PIs, which increase with longer PIs, anticues generate RT costs at short PIs and RT benefits at longer PIs. Our results showed that, in the anticue task, older participants needed more preparation time to turn RT costs into RT benefits than younger participants, revealing an age-related deficit of response inhibition. Moreover, in both tasks, older participants were less able to increase RT benefits with longer PIs, revealing a deficit of response facilitation. We conclude that both facilitatory and inhibitory impairments contribute to age-related deficiencies in proactive cognitive control., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Contemporary models of substance use disorders emphasize the role of cognitive control, which has been linked to difficulties in resisting the use of substances. In the present study, we measured two aspects of cognitive control, response inhibition (operationalized by a Go/NoGo Task) and performance monitoring (operationalized by an Eriksen Flanker Task), in a group of young cannabis-use disorder (CUD) patients and compared these functions with two control groups (i.e. a group of cigarette smokers and a group of non-smokers). We employed both behavioural and electrophysiological measures. The results indicate that CUD patients displayed reduced NoGo-P3 event-related potentials compared with non-smoking controls, but not compared with smoking controls. In addition, CUD patients were slower on Go trials than both control groups. No other between-group electrophysiological or behavioural differences were observed. These results seem to suggest that CUD patients have problems related to response inhibition, but performance monitoring seems relatively unaffected.

The "5-to-7-year shift" refers to the remarkable improvements observed in children's cognitive abilities during this age range, particularly in their ability to exert control over their attention and behavior-that is, their executive functioning. As this shift coincides with school entry, the extent to which it is driven by brain maturation or by exposure to formal schooling is unclear. In this longitudinal study, we followed 5-year-olds born close to the official cutoff date for entry into first grade and compared those who subsequently entered first grade that year with those who remained in kindergarten, which is more play oriented. The first graders made larger improvements in accuracy on an executive-function test over the year than did the kindergartners. In an independent functional MRI task, we found that the first graders, compared with the kindergartners, exhibited a greater increase in activation of right posterior parietal cortex, a region previously implicated in sustained attention; increased activation in this region was correlated with the improvement in accuracy. These results reveal how the environmental context of formal schooling shapes brain mechanisms underlying improved focus on cognitively demanding tasks.

Decreased cognitive control over the urge to be involved in gambling activities is a core feature of Gambling Disorder (GD). Cognitive control can be differentiated into several cognitive sub-processes pivotal in GD clinical phenomenology, such as response inhibition, conflict monitoring, decision-making, and cognitive flexibility. This article aims to systematically review fMRI studies, which investigated the neural mechanisms underlying diminished cognitive control in GD. We conducted a comprehensive literature search and collected neuropsychological and neuroimaging data investigating cognitive control in GD. We included a total of 14 studies comprising 499 individuals. Our results indicate that impaired activity in prefrontal cortex may account for decreased cognitive control in GD, contributing to the progressive loss of control over gambling urges. Among prefrontal regions, orbital and ventromedial areas seem to be a possible nexus for sensory integration, value-based decision-making and emotional processing, thus contributing to both motivational and affective aspects of cognitive control. Finally, we discussed possible therapeutic approaches aimed at the restoration of cognitive control in GD, including pharmacological and brain stimulation treatments., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

In standard Theory of Mind tasks, such as the Sally-Anne, children have to predict the behaviour of a mistaken character, which requires attributing the character a false belief. Hundreds of developmental studies in the last 30 years have shown that children under 4 fail standard false-belief tasks. However, recent studies have revealed that bilingual children and adults outperform their monolingual peers in this type of tasks. Bilinguals' better performance in false-belief tasks has generally been interpreted as a result of their better inhibitory control; that is, bilinguals are allegedly better than monolinguals at inhibiting the erroneous response to the false-belief question. In this review, I challenge the received view and argue instead that bilinguals' better false-belief performance results from more effective attention management. This challenge ties in with two independent lines of research: on the one hand, recent studies on the role of attentional processes in false-belief tasks with monolingual children and adults; and on the other, current research on bilinguals' performance in different Executive Function tasks. The review closes with an exploratory discussion of further benefits of bilingual cognition to Theory of Mind development and pragmatics, which may be independent from Executive Function.

The acute-exercise effects upon cognitive functions are varied and dependent upon exercise duration and intensity, and the type of cognitive tasks assessed. The hypofrontality hypothesis assumes that prolonged exercise, at physiologically challenging intensities, is detrimental to executive functions due to cerebral perturbations (indicated by reduced prefrontal activity). The present study aimed to test this hypothesis by measuring oxygenation in prefrontal and motor regions using near-infrared spectroscopy during two executive tasks (flanker task and 2-back task) performed while cycling for 60min at a very low intensity and an intensity above the ventilatory threshold. Findings revealed that, compared to very low intensity, physiologically challenging exercise (i) shortened reaction time in the flanker task, (ii) impaired performance in the 2-back task, and (iii) initially increased oxygenation in prefrontal, but not motor regions, which then became stable in both regions over time. Therefore, during prolonged exercise, not only is the intensity of exercise assessed important, but also the nature of the cognitive processes involved in the task. In contrast to the hypofrontality hypothesis, no inverse pattern of oxygenation between prefrontal and motor regions was observed, and prefrontal oxygenation was maintained over time. The present results go against the hypofrontality hypothesis., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The subthalamic nucleus (STN) of the basal ganglia appears to have a potent role in action and cognition. Anatomical and imaging studies show that different frontal cortical areas directly project to the STN via so-called hyperdirect pathways. This review reports some of the latest findings about such circuits, including simultaneous recordings from cortex and the STN in humans, single-unit recordings in humans, high-resolution fMRI, and neurocomputational modeling. We argue that a major function of the STN is to broadly pause behavior and cognition when stop signals, conflict signals, or surprise signals occur, and that the fronto-STN circuits for doing this, at least for stopping and conflict, are dissociable anatomically and in terms of their spectral reactivity. We also highlight recent evidence for synchronization of oscillations between prefrontal cortex and the STN, which may provide a preferential "window in time" for single neuron communication via long-range connections., (Copyright © 2016 the authors 0270-6474/16/3611489-07$15.00/0.)

Anxiety can have both detrimental and facilitatory cognitive effects. This study investigates the neural substrates of a replicated facilitatory effect of anxiety on sustained attention and response inhibition. This effect consisted of improved performance on the Sustained Attention to Response Task (a Go-NoGo task consisting of 91% Go and 9% NoGo trials) in threat (unpredictable electrical shock) vs safe (no shock) conditions. This study uses the same experimental design with fMRI and relies on an event-related analysis of BOLD signal changes. Findings reveal that threat-related cognitive facilitation (improved NoGo accuracy) is associated with greater activation of a right-lateralized frontoparietal group of regions previously implicated in sustained attention and response inhibition. Moreover, these same regions show decreased activation in the Go trials preceding NoGo errors. During NoGo trials, striatal activity is also greater in the threat vs safe condition, consistent with the notion of enhanced inhibitory processing under threat. These findings identify potential mechanisms by which threat of unpredictable shock can facilitate distinct cognitive functions. A greater understanding of the complex interaction of the anxious state and cognitive processes may have critical clinical implications., (Published by Oxford University Press 2016. This work is written by US Government employees and is in the public domain in the United States.)

Wilson's disease (WD) is a rare genetic disease causing copper deposits in various tissues. Given the specificity of the underlying pathology, it is a good model to investigate the effects of copper toxicity on cognitive functions in humans. If left untreated, WD results in neurodegeneration and organ failure, but irrespective of potential brain damage, the medication might reduce cortical norepinephrine (NE) levels. In line with this, dysexecutive symptoms including increased impulsivity have been reported for WD patients, but the underlying mechanisms have remained elusive. We investigated inhibition and the associated neurophysiological correlates in n = 26 WD patients with mild-to-moderate clinical symptoms and matched healthy controls who completed a Go/Nogo task, while an EEG was recorded. Although the behavioral data do not show increased impulsivity in WD, the neurophysiological data show that evaluative processing of successful inhibition (as reflected by the P3 component) was strongly compromised. This was reflected by a decrease in ACC activity which was positively correlated with the severity of WD symptoms, stressing the importance of copper (toxicity) for neurocognitive functioning and impulsivity. These changes are most likely due to a combination of NE deficiency induced by WD medication as well as WD-induced brain damage. The fact that changes were still evident on a neurophysiological level suggests that neurophysiological correlates of cognitive processes and functions provide a more sensitive index of toxicity and/or treatment efficiency than purely behavioral measures.

Loss-chasing is a central feature of problematic gambling, yet it remains a poorly conceived and understood concept. Loss-chasing is believed to stem from an erosion of cognitive control when gambling. The opportunity to gamble at significantly disparate stake sizes on a gambling activity is considered to be a risk factor for loss-chasing. This study investigated the impact of gambling at disparate stake sizes on executive processes integral to maintaining cognitive control when gambling, namely response inhibition and reflection impulsivity. Frequent adult non-problem gamblers (n = 32) participated in a repeated measures experiment; and gambled at three disparate stake sizes (£20, £2 and no stake per bet) on a simulated gambling task. Participants' response inhibition performance and reflection impulsivity levels after gambling at various stake sizes were compared via a go/no-go task and information sampling task, respectively. Quality of decision-making i.e. the evaluation of available information to make probability judgements was impaired after gambling at higher stakes in comparison to lower stakes, indicating an increase in reflection impulsivity. No effect on response inhibition was observed. Although exploratory, this suggests that the opportunity for participants to substantially increase stake size on a gambling activity may be a risk factor for impaired cognitive performance when gambling, and perhaps create vulnerability for within-session loss-chasing in some players.

Twenty-five percent of children with ADHD also have an anxiety disorder (AD). As per Quay and in light of Barkley's model, anxiety may have a protective effect on cognitive deficits and behaviors associated with ADHD. This study aimed to evaluate the effect of treating AD on cognitive deficits and behaviors associated with ADHD in children with both disorders. Twenty-four children with ADHD and AD were divided into two groups: treatment for AD, and wait list. Participants were assessed at pre-treatment, post-treatment, and 6-month follow-up with the ADIS-C, the CBCL, and neuropsychological measures. The results revealed a significant improvement in automatic response inhibition and flexibility, and a decrease in inattention/hyperactivity behaviors following the treatment for AD. No significant differences were observed in motor response inhibition, working memory, or attention deficits. The results do not seem to support Quay's hypothesis: treating AD did not exacerbate cognitive deficits and behaviors associated with ADHD in our sample.

Binge drinking is an increasing problem in Western societies, but we are still only beginning to unravel the effects of binge drinking on a cognitive level. While common sense suggests that all cognitive functions are compromised during high-dose ethanol intoxication, several studies suggest that the effects might instead be rather specific. Moreover, some results suggest that the degrees of automaticity and complexity of cognitive operations during response control modulate effects of binge drinking. However, this has not been tested in detail. In the current study, we therefore parametrically modulate cognitive/"mental" workload during response inhibition and examine the effects of high-dose ethanol intoxication (~1.1 ‰) in n = 18 male participants. The results suggest that detrimental effects of high-dose ethanol intoxication strongly depend on the complexity of processes involved in response inhibition. The results revealed strong effects (η (2) = .495) and are in line with findings showing that even high doses of ethanol have very specific effects on a cognitive level. Opposed to common sense, more complex cognitive operations seem to be less affected by a high-dose ethanol intoxication. Complementing this, high-dose ethanol intoxication is increasingly detrimental for action control, as stronger automated response tendencies are in charge and need to be controlled. Binge-like ethanol intoxication may take a heavier toll on cognitive control processes than on automated responses/response tendencies. Therefore, ethanol effects are more pronounced in supposedly "easier" control conditions because those facilitate the formation of automated response tendencies.

This study examined sex differences in executive function in middle-aged gonadectomized marmosets (Callithrix jacchus) with or without hormonal replacement. We tested ten castrated male (mean age 5.5 years) marmosets treated with testosterone cypionate (T, n = 5) or vehicle (n = 5) on Reversal Learning, which contributes to cognitive flexibility, and the Delayed Response task, measuring working memory. Their performance was compared to that of 11 ovariectomized females (mean age = 3.7 years) treated with Silastic capsules filled with 17-β estradiol (E2, n = 6) or empty capsules (n = 5), previously tested on the same tasks (Lacreuse et al. in J Neuroendocrinol 26:296-309, 2014. doi: 10.1111/jne.12147). Behavioral observations were conducted daily. Females exhibited more locomotor behaviors than males. Males and females did not differ in the number of trials taken to reach criterion on the reversals, but males had significantly longer response latencies, regardless of hormone replacement. They also had a greater number of refusals than females. Additionally, both control and T-treated males, but not females, had slower responses on incorrect trials, suggesting that males were making errors due to distraction, lack of motivation or uncertainty. Furthermore, although both males and females had slower responding following an incorrect compared to a correct trial, the sex difference in response latencies was disproportionally large following an incorrect trial. No sex difference was found in the Delayed Response task. Overall, slower response latencies in males than females during Reversal Learning, especially during and following an incorrect trial, may reflect greater sensitivity to punishment (omission of reward) and greater performance monitoring in males, compared to females. Because these differences occurred in gonadectomized animals and regardless of hormone replacement, they may be organized early in life.

Background: Attention-deficit/hyperactivity disorder (ADHD) is one of the most prevalent neuropsychiatric disorders in childhood. Besides inattention and hyperactivity, impulsivity is the third core symptom leading to diverse and serious problems. However, the neuronal mechanisms underlying impulsivity in ADHD are still not fully understood. This is all the more the case when patients with the ADHD combined subtype (ADHD-C) are considered who are characterized by both symptoms of inattention and hyperactivity/impulsivity., Method: Combining high-density electroencephalography (EEG) recordings with source localization analyses, we examined what information processing stages are dysfunctional in ADHD-C (n = 20) compared with controls (n = 18)., Results: Patients with ADHD-C made more impulsive errors in a Go/No-go task than healthy controls. Neurophysiologically, different subprocesses from perceptual gating to attentional selection, resource allocation and response selection processes are altered in this patient group. Perceptual gating, stimulus-driven attention selection and resource allocation processes were more pronounced in ADHD-C, are related to activation differences in parieto-occipital networks and suggest attentional filtering deficits. However, only response selection processes, associated with medial prefrontal networks, predicted impulsive errors in ADHD-C., Conclusions: Although the clinical picture of ADHD-C is complex and a multitude of processing steps are altered, only a subset of processes seems to directly modulate impulsive behaviour. The present findings improve the understanding of mechanisms underlying impulsivity in patients with ADHD-C and might help to refine treatment algorithms focusing on impulsivity.

Children with attention-deficit hyperactivity disorder (ADHD) consistently show impaired response control, including deficits in response inhibition and increased intrasubject variability (ISV) compared to typically-developing (TD) children. However, significantly less research has examined factors that may influence response control in individuals with ADHD, such as task or participant characteristics. The current study extends the literature by examining the impact of increasing cognitive demands on response control in a large sample of 81children with ADHD (40 girls) and 100 TD children (47 girls), ages 8-12 years. Participants completed a simple Go/No-Go (GNG) task with minimal cognitive demands, and a complex GNG task with increased cognitive load. Results showed that increasing cognitive load differentially impacted response control (commission error rate and tau, an ex-Gaussian measure of ISV) for girls, but not boys, with ADHD compared to same-sex TD children. Specifically, a sexually dimorphic pattern emerged such that boys with ADHD demonstrated higher commission error rate and tau on both the simple and complex GNG tasks as compared to TD boys, whereas girls with ADHD did not differ from TD girls on the simple GNG task, but showed higher commission error rate and tau on the complex GNG task. These findings suggest that task complexity influences response control in children with ADHD in a sexually dimorphic manner. The findings have substantive implications for the pathophysiology of ADHD in boys versus girls with ADHD.

Aside from well-known physiological effects, high-dose alcohol intoxication (a.k.a. binge drinking) can lead to aversive social and legal consequences because response inhibition is usually compromised under the influence of alcohol. Although the behavioral aspects of this phenomenon were reported on extensively, the underlying neurophysiological mechanisms mediating this disinhibition are unclear. To close this gap, we used both behavioral and neurophysiological measures (event-related potentials, ERPs) to investigate which subprocesses of response inhibition are altered under the influence of high-dose alcohol intoxication. Using a within-subject design, we asked young healthy participants (n = 27) to complete a GO/NOGO task once sober and once intoxicated (approximately 1.2‰). During intoxication, high-dose alcohol effects were highest in a condition where the participants could not rely on automated stimulus-response mapping processes during response inhibition. In this context, the NOGO-P3 (ERP), that likely depends on dopaminergic signaling within mesocorticolimbic pathways and is thought to reflect motor inhibition and/or the evaluation of inhibitory processes, was altered in the intoxicated state. In contrast to this, the N2 component, which largely depends on nigrostriatal dopamine pathways and is thought to reflect inhibition on a pre-motor level, was not altered. Based on these results, we demonstrate that alcohol-induced changes of dopaminergic neurotransmission do not exert a global effect on response inhibition. Instead, changes are highly subprocess-specific and seem to mainly target mesocorticolimbic pathways that contribute to motor inhibition and the evaluation of such., (© 2014 Society for the Study of Addiction.)

Is it easier to inhibit inappropriate behaviors if one pauses before acting? An important finding for theory and intervention is that children's inhibitory control improves if an adult imposes a delay before they can act. Such findings have suggested that the passage of time allows impulsive urges to dissipate passively. However, in prior studies with imposed delays, children were also reminded about what they should be doing, which may have aided their activation of goal-relevant information. We tested this possibility by independently manipulating delays and task reminders, and measuring 3-year-olds' abilities to inhibit opening boxes in a go/no-go box-search task. Task reminders, but not adult-imposed delays, improved children's response inhibition. However, as in prior work, children who spontaneously delayed their action longer on go trials exhibited better response inhibition on no-go trials. These results pose a challenge to the view that the passage of time plays a causal role, suggest that spontaneous delays index other processes that improve inhibitory control, and highlight the importance of goal activation in developing inhibitory control., (© The Author(s) 2015.)

Rationale: The NEWMEDS initiative (Novel Methods leading to New Medications in Depression and Schizophrenia, http://www.newmeds-europe.com ) is a large industrial-academic collaborative project aimed at developing new methods for drug discovery for schizophrenia. As part of this project, Work package 2 (WP02) has developed and validated a comprehensive battery of novel touchscreen tasks for rats and mice for assessing cognitive domains relevant to schizophrenia., Objectives: This article provides a review of the touchscreen battery of tasks for rats and mice for assessing cognitive domains relevant to schizophrenia and highlights validation data presented in several primary articles in this issue and elsewhere., Methods: The battery consists of the five-choice serial reaction time task and a novel rodent continuous performance task for measuring attention, a three-stimulus visual reversal and the serial visual reversal task for measuring cognitive flexibility, novel non-matching to sample-based tasks for measuring spatial working memory and paired-associates learning for measuring long-term memory., Results: The rodent (i.e. both rats and mice) touchscreen operant chamber and battery has high translational value across species due to its emphasis on construct as well as face validity. In addition, it offers cognitive profiling of models of diseases with cognitive symptoms (not limited to schizophrenia) through a battery approach, whereby multiple cognitive constructs can be measured using the same apparatus, enabling comparisons of performance across tasks., Conclusion: This battery of tests constitutes an extensive tool package for both model characterisation and pre-clinical drug discovery.

Previous research has demonstrated that brain stimulation can improve inhibitory control. However, the neural mechanisms underlying such artificially induced improvement remain unclear. In this study, by coupling anodal transcranial direct current stimulation (atDCS) with functional MRI, we found that atDCS over preSMA effectively improved stopping speed, which was associated with increased BOLD response in the preSMA and ventromedial prefrontal cortex (vmPFC). Furthermore, such atDCS-induced BOLD increase in vmPFC was positively correlated with participants' improvement in stopping efficiency, and the functional connectivity between preSMA and vmPFC increased during successful stop. These results suggest that the rapid behavioral improvement from preSMA brain stimulation involves modulated medial-frontal activity and preSMA-vmPFC functional connectivity., (© 2015 Wiley Periodicals, Inc.)

Shooting a firearm involves a complex series of cognitive abilities. For example, locating an item or a person of interest requires visual search, and firing the weapon (or withholding a trigger squeeze) involves response execution (or inhibition). The present study used a simulated shooting environment to establish a relationship between a particular cognitive ability and a critical shooting error-response inhibition and firing on civilians, respectively. Individual-difference measures demonstrated, perhaps counterintuitively, that simulated civilian casualties were not related to motor impulsivity (i.e., an itchy trigger finger) but rather to an individual's cognitive ability to withhold an already initiated response (i.e., an itchy brain). Furthermore, active-response-inhibition training reduced simulated civilian casualties, which revealed a causal relationship. This study therefore illustrates the potential of using cognitive training to possibly improve shooting performance, which might ultimately provide insight for military and law-enforcement personnel., (© The Author(s) 2015.)

A prominent theory proposes that the right inferior frontal cortex of the human brain houses a dedicated region for motor response inhibition. However, there is growing evidence to support the view that this inhibitory control hypothesis is incorrect. Here, we discuss evidence in favour of our alternative hypothesis, which states that response inhibition is one example of a broader class of control processes that are supported by the same set of frontoparietal networks. These domain-general networks exert control by modulating local lateral inhibition processes, which occur ubiquitously throughout the cortex. We propose that to fully understand the neural basis of behavioural control requires a more holistic approach that considers how common network mechanisms support diverse cognitive processes., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: Developing reliable and specific neural markers of cognitive processes is essential to improve understanding of healthy and atypical brain function. Despite extensive research there remains uncertainty as to whether two electrophysiological markers of cognitive control, the N2 and P3, are better conceptualised as markers of response inhibition or response conflict. The present study aimed to directly compare the effects of response inhibition and response conflict on the N2 and P3 event-related potentials, within-subjects., Method: A novel hybrid go/no-go flanker task was performed by 19 healthy adults aged 18-25 years while EEG data were collected. The response congruence of a central target stimulus and 4 flanking stimuli was manipulated between trials to vary the degree of response conflict. Response inhibition was required on a proportion of trials. N2 amplitude was measured at two frontal electrode sites; P3 amplitude was measured at 4 midline electrode sites., Results: N2 amplitude was greater on incongruent than congruent trials but was not enhanced by response inhibition when the stimulus array was congruent. P3 amplitude was greater on trials requiring response inhibition; this effect was more pronounced at frontal electrodes. P3 amplitude was also enhanced on incongruent compared with congruent trials., Discussion: The findings support a role for N2 amplitude as a marker of response conflict and for the frontal shift of the P3 as a marker of response inhibition. This paradigm could be applied to clinical groups to help clarify the precise nature of impaired action control in disorders such as attention deficit/hyperactivity disorders (ADHD)., (Copyright © 2015 Elsevier Inc. All rights reserved.)