The Experts below are selected from a list of 309831 Experts worldwide ranked by ideXlab platform
Cameron S Carter - One of the best experts on this subject based on the ideXlab platform.
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using prefrontal transcranial direct current stimulation tdcs to enhance proactive Cognitive Control in schizophrenia
Neuropsychopharmacology, 2020Co-Authors: Megan A Boudewyn, Katherine W Scangos, Charan Ranganath, Cameron S CarterAbstract:The goal of this study was to use transcranial direct current stimulation (tDCS) to examine the role of the prefrontal cortex (PFC) in neural oscillatory activity associated with proactive Cognitive Control in schizophrenia. To do so, we tested the impact of PFC-targeted tDCS on behavioral and electrophysiological markers of proactive Cognitive Control engagement in individuals with schizophrenia. Using a within-participants, double-blinded, sham-Controlled crossover design, we recorded EEG while participants with schizophrenia completed a proactive Cognitive Control task (the Dot Pattern Expectancy (DPX) Task), after receiving 20 min of active prefrontal stimulation at 2 mA or sham stimulation. We hypothesized that active stimulation would enhance proactive Cognitive Control, leading to changes in behavioral performance on the DPX task and in activity in the gamma frequency band during key periods of the task designed to tax proactive Cognitive Control. The results showed significant changes in the pattern of error rates and increases in EEG gamma power as a function of tDCS condition (active or sham), that were indicative of enhanced proactive Cognitive Control. These findings, considered alongside our previous work in healthy adults, provides novel support for the role gamma oscillations in proactive Cognitive Control and they suggest that frontal tDCS may be a promising approach to enhance proactive Cognitive Control in schizophrenia.
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general and specific functional connectivity disturbances in first episode schizophrenia during Cognitive Control performance
Biological Psychiatry, 2011Co-Authors: Jong H Yoon, Alex Fornito, Andrew Zalesky, Edward T Bullmore, Cameron S CarterAbstract:Background Cognitive Control impairments in schizophrenia are thought to arise from dysfunction of interconnected networks of brain regions, but interrogating the functional dynamics of large-scale brain networks during Cognitive task performance has proved difficult. We used functional magnetic resonance imaging to generate event-related whole-brain functional connectivity networks in participants with first-episode schizophrenia and healthy Control subjects performing a Cognitive Control task. Methods Functional connectivity during Cognitive Control performance was assessed between each pair of 78 brain regions in 23 patients and 25 Control subjects. Network properties examined were region-wise connectivity, edge-wise connectivity, global path length, clustering, small-worldness, global efficiency, and local efficiency. Results Patients showed widespread functional connectivity deficits in a large-scale network of brain regions, which primarily affected connectivity between frontal cortex and posterior regions and occurred irrespective of task context. A more circumscribed and task-specific connectivity impairment in frontoparietal systems related to Cognitive Control was also apparent. Global properties of network topology in patients were relatively intact. Conclusions The first episode of schizophrenia is associated with a generalized connectivity impairment affecting most brain regions but that is particularly pronounced for frontal cortex. Superimposed on this generalized deficit, patients show more specific Cognitive-Control-related functional connectivity reductions in frontoparietal regions. These connectivity deficits occur in the context of relatively preserved global network organization.
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impairments in frontal cortical γ synchrony and Cognitive Control in schizophrenia
Proceedings of the National Academy of Sciences of the United States of America, 2006Co-Authors: Raymond Y Cho, Cameron S Carter, Roma O KoneckyAbstract:A critical component of Cognitive impairments in schizophrenia can be characterized as a disturbance in Cognitive Control, or the ability to guide and adjust Cognitive processes and behavior flexibly in accordance with one's intentions and goals. Cognitive Control impairments in schizophrenia are consistently linked to specific disturbances in prefrontal cortical functioning, but the underlying neurophysiologic mechanisms are not yet well characterized. Synchronous γ-band oscillations have been associated with a wide range of perceptual and Cognitive processes, raising the possibility that they may also help entrain prefrontal cortical circuits in the service of Cognitive Control processes. In the present study, we measured induced γ-band activity during a task that reliably engages Cognitive Control processes in association with prefrontal cortical activations in imaging studies. We found that higher Cognitive Control demands were associated with increases in induced γ-band activity in the prefrontal areas of healthy subjects but that Control-related modulation of prefrontal γ-band activity was absent in schizophrenia subjects. Disturbances in γ-band activity in patients correlated with illness symptoms, and γ-band activity correlated positively with performance in Control subjects but not in schizophrenia patients. Our findings may provide a link between previously reported postmortem abnormalities in thalamofrontocortical circuitry and alterations in prefrontal activity observed in functional neuroimaging studies. They also suggest that deficits in frontal cortical γ-band synchrony may contribute to the Cognitive Control impairments in schizophrenia.
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conflict monitoring and Cognitive Control
Psychological Review, 2001Co-Authors: Matthew Botvinick, Todd S Braver, Deanna M, Cameron S Carter, Jonathan D CohenAbstract:A neglected question regarding Cognitive Control is how Control processes might detect situations calling for their involvement. The authors propose here that the demand for Control may be evaluated in part by monitoring for conflicts in information processing. This hypothesis is supported by data concerning the anterior cingulate cortex, a brain area involved in Cognitive Control, which also appears to respond to the occurrence of conflict. The present article reports two computational modeling studies, serving to articulate the conflict monitoring hypothesis and examine its implications. The first study tests the sufficiency of the hypothesis to account for brain activation data, applying a measure of conflict to existing models of tasks shown to engage the anterior cingulate. The second study implements a feedback loop connecting conflict monitoring to Cognitive Control, using this to simulate a number of important behavioral phenomena.
Essi Viding - One of the best experts on this subject based on the ideXlab platform.
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load theory of selective attention and Cognitive Control
Journal of Experimental Psychology: General, 2004Co-Authors: Nilli Lavie, Aleksandra Hirst, Jan W. Fockert, Essi VidingAbstract:A load theory of attention in which distractor rejection depends on the level and type of load involved in current processing was tested. A series of experiments demonstrates that whereas high perceptual load reduces distractor interference, working memory load or dual-task coordination load increases distractor interference. These findings suggest 2 selective attention mechanisms: a perceptual selection mechanism serving to reduce distractor perception in situations of high perceptual load that exhaust perceptual capacity in processing relevant stimuli and a Cognitive Control mechanism that reduces interference from perceived distractors as long as Cognitive Control functions are available to maintain current priorities (low Cognitive load). This theory resolves the long-standing early versus late selection debate and clarifies the role of Cognitive Control in selective attention. (PsycINFO Database Record (c) 2009 APA, all rights reserved)
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Load theory of selective attention and Cognitive Control
Journal of Experimental Psychology: General, 2004Co-Authors: Nilli Lavie, Aleksandra Hirst, Jan W. Fockert, Essi VidingAbstract:A load theory of attention in which distractor rejection depends on the level and type of load involved in current processing was tested. A series of experiments demonstrates that whereas high perceptual load reduces distractor interference, working memory load or dual-task coordination load increases distractor interference. These findings suggest 2 selective attention mechanisms: a perceptual selection mechanism serving to reduce distractor perception in situations of high perceptual load that exhaust perceptual capacity in processing relevant stimuli and a Cognitive Control mechanism that reduces interference from perceived distractors as long as Cognitive Control functions are available to maintain current priorities (low Cognitive load). This theory resolves the long-standing early versus late selection debate and clarifies the role of Cognitive Control in selective attention.
Jin Fan - One of the best experts on this subject based on the ideXlab platform.
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anterior insular cortex is a bottleneck of Cognitive Control
NeuroImage, 2019Co-Authors: Xingchao Wang, Alfredo Spagna, Jiaqi Yang, Changhe Yuan, Zhixian Gao, Patrick R Hof, Jin FanAbstract:Cognitive Control, with a limited capacity, is a core process in human cognition for the coordination of thoughts and actions. Although the regions involved in Cognitive Control have been identified as the Cognitive Control network (CCN), it is still unclear whether a specific region of the CCN serves as a bottleneck limiting the capacity of Cognitive Control (CCC). Here, we used a perceptual decision-making task with conditions of high Cognitive load to challenge the CCN and to assess the CCC in a functional magnetic resonance imaging study. We found that the activation of the right anterior insular cortex (AIC) of the CCN increased monotonically as a function of Cognitive load, reached its plateau early, and showed a significant correlation to the CCC. In a subsequent study of patients with unilateral lesions of the AIC, we found that lesions of the AIC were associated with a significant impairment of the CCC. Simulated lesions of the AIC resulted in a reduction of the global efficiency of the CCN in a network analysis. These findings suggest that the AIC, as a critical hub in the CCN, is a bottleneck of Cognitive Control.
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Testing a Cognitive Control Model of Human Intelligence
Scientific Reports, 2019Co-Authors: Yu Chen, Alfredo Spagna, Tae Hyeong Kim, Caiqi Chen, Jin FanAbstract:The definition of human intelligence and its underlying psychological constructs have long been debated. Although previous studies have investigated the fundamental Cognitive functions determining intellectual abilities, such as the broadly defined executive functions including working memory, the core process has yet to be identified. A potential candidate for such a role might be Cognitive Control, a psychological construct for the coordination of thoughts and actions under conditions of uncertainty. In this study, we tested a Cognitive Control model of intellectual ability by examining the association between Cognitive Control, measured by a perceptual decision-making task and by the attention network test, and general intelligence including components of fluid intelligence (Gf, concerning the ability to solve problems by abstraction) and crystalized intelligence (Gc, related to learning from prior knowledge and experience) measured by the Wechsler Adult Intelligence Scale. We also examined the potential role of Cognitive Control as a core process involved in another determinant of intellectual abilities, the working memory, measured by the N-back tasks and the working memory complex span tasks. The relationship among intelligence, Cognitive Control, and working memory was examined using structural equation modeling. Results showed that Cognitive Control shared a large amount of variance with working memory and both measures were strongly associated with Gf and Gc, with a stronger association with Gf than Gc. These findings suggest that Cognitive Control, serving as a core construct of executive functions, contributes substantially to general intellectual ability, especially fluid intelligence.
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emotional bias of Cognitive Control in adults with childhood attention deficit hyperactivity disorder
NeuroImage: Clinical, 2014Co-Authors: Kurt P Schulz, Anneclaude V Bedard, Jeffrey H Newcorn, Jin Fan, Suzanne M. Clerkin, Danai Dima, Jeffrey M. HalperinAbstract:Affect recognition deficits found in individuals with attention-deficit/hyperactivity disorder (ADHD) across the lifespan may bias the development of Cognitive Control processes implicated in the pathophysiology of the disorder. This study aimed to determine the mechanism through which facial expressions influence Cognitive Control in young adults diagnosed with ADHD in childhood. Fourteen probands with childhood ADHD and 14 comparison subjects with no history of ADHD were scanned with functional magnetic resonance imaging while performing a face emotion go/no-go task. Event-related analyses contrasted activation and functional connectivity for Cognitive Control collapsed over face valence and tested for variations in activation for response execution and inhibition as a function of face valence. Probands with childhood ADHD made fewer correct responses and inhibitions overall than comparison subjects, but demonstrated comparable effects of face emotion on response execution and inhibition. The two groups showed similar frontotemporal activation for Cognitive Control collapsed across face valence, but differed in the functional connectivity of the right dorsolateral prefrontal cortex, with fewer interactions with the subgenual cingulate cortex, inferior frontal gyrus, and putamen in probands than in comparison subjects. Further, valence-dependent activation for response execution was seen in the amygdala, ventral striatum, subgenual cingulate cortex, and orbitofrontal cortex in comparison subjects but not in probands. The findings point to functional anomalies in limbic networks for both the valence-dependent biasing of Cognitive Control and the valence-independent Cognitive Control of face emotion processing in probands with childhood ADHD. This limbic dysfunction could impact Cognitive Control in emotional contexts and may contribute to the social and emotional problems associated with ADHD.
Dick J Veltman - One of the best experts on this subject based on the ideXlab platform.
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modafinil modulates resting state functional network connectivity and Cognitive Control in alcohol dependent patients
Biological Psychiatry, 2013Co-Authors: Lianne Schmaal, Anna E Goudriaan, Leen Joos, Anne Maren Kruse, Wim Van Den Brink, Dick J VeltmanAbstract:Background Chronic alcohol abuse is associated with deficits in Cognitive Control functions. Cognitive Control is likely to be mediated through the interaction between intrinsic large-scale brain networks involved in externally oriented executive functioning and internally focused thought processing. Improving the interaction between these functional brain networks could be an important target for treatment. Therefore, the current study aimed to investigate the effects of the Cognitive enhancer modafinil on within-network and between-network resting-state functional connectivity and Cognitive Control functions in alcohol-dependent patients. Methods In a double-blind, placebo-Controlled cross-over design, resting-state functional magnetic resonance imaging and a Stroop task were employed in alcohol-dependent patients ( n = 15) and healthy Control subjects ( n = 16). Within-network and between-network functional connectivity was calculated using a combination of independent component analysis and functional network connectivity analysis. Results Modafinil significantly increased the negative coupling between executive networks and the default mode network, which was associated with modafinil-induced improvement in Cognitive Control in alcohol-dependent patients. Conclusions These findings demonstrate that modafinil at least partly exerts its effects by targeting intrinsic functional relationships between large-scale brain systems underlying Cognitive Control. The current study therefore provides a neurobiological rationale for implementing modafinil as an adjunct in the treatment of alcohol dependence, although clinical studies are needed to substantiate this promise.
Tristan A Bekinschtein - One of the best experts on this subject based on the ideXlab platform.
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decreased alertness reconfigures Cognitive Control networks
The Journal of Neuroscience, 2020Co-Authors: Andres Canalesjohnson, Lola Beerendonk, Salome Blain, Shin Kitaoka, Alejandro Ezquerronassar, Stijn A Nuiten, Johannes J Fahrenfort, Simon Van Gaal, Tristan A BekinschteinAbstract:Humans’ remarkable capacity to flexibly adapt their behaviour based on rapid situational changes is termed Cognitive Control. Intuitively, Cognitive Control is thought to be affected by the state of alertness, for example, when drowsy we feel less capable of adequately implementing effortful Cognitive tasks. Although scientific investigations have focused on the effects of sleep deprivation and circadian time, little is known about how natural daily fluctuations in alertness in the regular awake state affect Cognitive Control. Here we combined a conflict task in the auditory domain with EEG neurodynamics to test how neural and behavioural markers of conflict processing are affected by fluctuations in alertness. Using a novel computational method, we segregated alert and drowsy trials from two testing sessions and observed that, although participants (both sexes) were generally sluggish, the typical Conflict Effect reflected in slower responses to conflicting information compared to non-conflicting information was still intact, as well as the moderating effect of previous conflict (Conflict Adaptation). However, the typical neural markers of Cognitive Control -local midfrontal theta-band power changes- that participants show during full alertness were no longer noticeable when alertness decreased. Instead, when drowsy, we found an increase in long-range information sharing (connectivity) between brain regions in the same frequency band. These results show the resilience of the human Cognitive Control system when affected by internal fluctuations of alertness, and suggest neural compensatory mechanisms at play in response to physiological pressure during diminished alertness. SIGNIFICANCE STATEMENT The normal variability in alertness we experience in daily tasks is rarely taking into account in Cognitive neuroscience. Here we studied neurobehavioral dynamics of Cognitive Control with decreasing alertness. We used the classic Simon Task where participants hear the word "left" or "right" in the right or left ear, eliciting slower responses when the word and the side are incongruent - the conflict effect. Participants performed the task both while fully awake and while getting drowsy, allowing for the characterisation of alertness modulating Cognitive Control. The changes in the neural signatures of conflict from local theta oscillations to a long-distance distributed theta network suggests a reconfiguration of the underlying neural processes subserving Cognitive Control when affected by alertness fluctuations.
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decreased alertness reconfigures Cognitive Control networks
bioRxiv, 2019Co-Authors: Andres Canalesjohnson, Lola Beerendonk, Salome Blain, Shin Kitaoka, Alejandro Ezquerronassar, Stijn A Nuiten, Johannes J Fahrenfort, Simon Van Gaal, Tristan A BekinschteinAbstract:Abstract Humans are remarkably capable of adapting their behaviour flexibly based on rapid situational changes: a capacity termed Cognitive Control. Intuitively, Cognitive Control is thought to be affected by the state of alertness, for example, when sleepy or drowsy, we feel less capable of adequately implementing effortful Cognitive tasks. Although scientific investigations have focused on the effects of sleep deprivation and circadian time, little is known about how natural fluctuations in alertness in the regular awake state affect Cognitive Control. Here we combined a conflict task in the auditory domain with neurodynamics -EEG recordings-to test how neural and behavioural markers of conflict processing are affected by fluctuations in arousal. Using a novel computational method, we segregated alert and drowsy trials from a three hour testing session and observed that, although participants were generally slower, the typical slower responses to conflicting information, compared to non-conflicting information, was still intact, as well as the effect of previous trials (i.e. conflict adaptation). However, the behaviour was not matched by the typical neural markers of Cognitive Control -local medio-frontal theta-band power changes-, that participants showed during full alertness. Instead, a decrease in power of medio-frontal theta was accompanied by an increase in long-range information sharing (connectivity) between brain regions in the same frequency band. The results show the resilience of the human Cognitive Control system when affected by internal fluctuations of our arousal state and suggests a neural compensatory mechanism when the system is under physiological pressure due to diminished alertness.
