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An influential model of executive control suggests that it comprises three dissociable processes: working memory, inhibition, and task switching. Multiple studies have investigated how these processes are individually implemented in the human brain. However, few have directly investigated this question using a common task architecture and a within-subject design. Here, healthy adult humans (N = 22) performed a novel executive control task during fMRI scanning. The paradigm independently manipulated working memory updating, inhibition, and task switching demands, while keeping all other task features constant. Direct contrasts of each executive task with a closely matched control condition revealed a differentiated pattern of recruitment across control tasks: working memory was associated with activity in dorsolateral prefrontal, lateral parietal and insular cortices bilaterally; Inhibition engaged right lateral and superior medial prefrontal cortex, inferior parietal lobules bilaterally, right middle and inferior temporal cortex, and ventral visual processing regions; Task switching was associated with bilateral activity in medial prefrontal cortex, posterior cingulate cortex and precuneus, as well as left inferior parietal lobule, lateral temporal cortex and right thalamus. A conjunction of all executive versus control task activations revealed common areas of activation overlapping regions of canonical frontoparietal control and dorsal attention networks. Further, multivariate analyses suggest that working memory may be a putative common factor supporting executive functioning. Taken together, these results are consistent with a hybrid model of executive control in the human brain., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Cognitive aging is often described in the context of loss or decline. Emerging research suggests that the story is more complex, with older adults showing both losses and gains in cognitive ability. With increasing age, declines in controlled, or fluid, cognition occur in the context of gains in crystallized knowledge of oneself and the world. This inversion in cognitive capacities, from greater reliance on fluid abilities in young adulthood to increasingly crystallized or semanticized cognition in older adulthood, has profound implications for cognitive and real-world functioning in later life. The shift in cognitive architecture parallels changes in the functional network architecture of the brain. Observations of greater functional connectivity between lateral prefrontal brain regions, implicated in cognitive control, and the default network, implicated in memory and semantic processing, led us to propose the default-executive coupling hypothesis of aging . In this review we provide evidence that these changes in the functional architecture of the brain serve as a neural mechanism underlying the shifting cognitive architecture from younger to older adulthood. We incorporate findings spanning cognitive aging and cognitive neuroscience to present an integrative model of cognitive and brain aging, describing its antecedents, determinants, and implications for real-world functioning.

Some degree of ischemic injury to white matter tracts occurs naturally with age and is visible on magnetic resonance imaging as focal or confluent white matter hyperintensities. Its relationship to cognition, however, remains unclear. To explore this, community-dwelling adults between the ages 55 and 80 years completed structural imaging, neuropsychological testing, and questionnaires to provide objective measures and subjective experience of executive functioning. Volumetric lesion burden derived from structural MRI identified those with significant white matter hyperintensity burden (∼10 cm 3 ). Half of those recruited met this criterion and were designated as the cerebral small vessel disease (CSVD) group. Subjective cognitive complaints but not objective test scores differentiated adults with and without CSVD. Hierarchical clustering revealed 2 CSVD subgroups that differentiated those with impaired versus preserved executive function relative to controls. Overall these results provide some explanation for behavioral heterogeneity often observed in studies of age-related white matter changes. They also support the use of questionnaires to assess subjective cognitive complaints that may point to subtle effects of vascular pathology not evident on standardized cognitive scores., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objectives: Youth and young adults with pediatric-onset multiple sclerosis (MS) are vulnerable to executive dysfunction; however, some patients do not demonstrate functional deficits despite showing abnormalities on structural magnetic resonance imaging (MRI). Cognitively intact adults with MS have shown enhanced activation patterns relative to healthy controls on working memory tasks. We aim to evaluate whether cognitively preserved pediatric-onset MS patients engage compensatory recruitment strategies to facilitate age-normative performance on a task of working memory., Methods: Twenty cognitively preserved patients (mean age=18.7±2.7 years; 15 female) and 20 age- and sex-matched controls (mean age=18.5±2.9 years; 15 female) underwent neuropsychological testing and 3.0 Tesla MRI, including structural and functional acquisitions. Patterns of activation during the Alphaspan task, a working memory paradigm with two levels of executive control demand, were examined via whole-brain and region of interest (ROI) analyses., Results: Across all participants, lower accuracy and greater activation of regions implicated in working memory were observed during the high demand condition. MS patients demonstrated 0.21 s longer response time than controls. ROI analyses revealed enhanced activation for pediatric-onset MS patients relative to controls in the right middle frontal, left paracingulate, right supramarginal, and left superior parietal gyri during the low executive demand condition, over and above differences in response time. MS patients also demonstrated heightened activation in the right supramarginal gyrus in the high executive demand condition., Conclusions: Our findings suggest that pediatric-onset MS patients may engage compensatory recruitment strategies during working memory processing. (JINS, 2019, 25, 432-442).

Background: While older adults are able to attend to goal-relevant information, the capacity to ignore irrelevant or distracting information declines with advancing age. This decline in selective attention has been associated with poor modulation of brain activity in sensory cortices by anterior brain regions implicated in cognitive control., Objective: Here we investigated whether participation in an executive control training program would result in improved selective attention and associated functional brain changes in a sample of healthy older adults (N = 24, age 60-85 years)., Methods: Participants were enrolled in a goal-oriented attentional self-regulation (GOALS) program (n = 11) or a brain health education workshop as an active control condition (n = 13). All participants performed a working memory task requiring attention to or suppression of visual stimuli based on goal-relevance during functional magnetic resonance imaging., Results: We observed a pattern of enhanced activity in right frontal, parietal and temporal brain regions from pre- to posttraining in the GOALS intervention group, which predicted the selectivity of subsequent memory for goal-relevant stimuli., Conclusions: Executive control training in older adults alters functional activity in brain regions associated with attentional control, and selectively predicts behavioral outcome.

Aging is accompanied by declines in executive control abilities and changes in underlying brain network architecture. Here, we examined brain networks in young and older adults during a task-free resting state and an N-back task and investigated age-related changes in the modular network organization of the brain. Compared with young adults, older adults showed larger changes in network organization between resting state and task. Although young adults exhibited increased connectivity between lateral frontal regions and other network modules during the most difficult task condition, older adults also exhibited this pattern of increased connectivity during less-demanding task conditions. Moreover, the increase in between-module connectivity in older adults was related to faster task performance and greater fractional anisotropy of the superior longitudinal fasciculus. These results demonstrate that older adults who exhibit more pronounced network changes between a resting state and task have better executive control performance and greater structural connectivity of a core frontal-posterior white matter pathway., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Reduced executive control is a hallmark of neurocognitive aging. Poor modulation of lateral pFC activity in the context of increasing task challenge in old adults and a "failure to deactivate" the default network during cognitive control tasks have been observed. Whether these two patterns represent discrete mechanisms of neurocognitive aging or interact into older adulthood remains unknown. We examined whether altered pFC and default network dynamics co-occur during goal-directed planning over increasing levels of difficulty during performance on the Tower of London task. We used fMRI to investigate task- and age-related changes in brain activation and functional connectivity across four levels of task challenge. Frontoparietal executive control regions were activated and default network regions were suppressed during planning relative to counting performance in both groups. Older adults, unlike young, failed to modulate brain activity in executive control and default regions as planning demands increased. Critically, functional connectivity analyses revealed bilateral dorsolateral pFC coupling in young adults and dorsolateral pFC to default coupling in older adults with increased planning complexity. We propose a default-executive coupling hypothesis of aging. First, this hypothesis suggests that failure to modulate control and default network activity in response to increasing task challenge are linked in older adulthood. Second, functional brain changes involve greater coupling of lateral pFC and the default network as cognitive control demands increase in older adults. We speculate that these changes reflect an adaptive shift in cognitive approach as older adults come to rely more upon stored representations to support goal-directed task performance.

Impairments in executive function, self-regulation and attribution individually have been implicated in impairment in goal-directed behaviour, resulting in reduced participation in daily activities by individuals with brain injury. There is minimal literature that explicitly addresses the relationships among these constructs, how these may be affected by brain injury and the implications for rehabilitation. The objectives of this study were to determine what is known about the relationship between executive function, self-regulation and attribution, and to understand how these inter-relationships affect goal-directed behaviour in adults with acquired brain injury. A scoping review of the cognitive neuroscience, neuropsychology, rehabilitation, educational and social psychology literature from 1985 to 2011 was performed. The identified literature provided definitions of the constructs and insight into the relationships between them according to their neural underpinnings and theoretical models. These data also provided for the development of a new model illustrating the hypothesised relationships between constructs. This review and the model developed, suggest that attribution may play an important role in executive function and self-regulation. Rehabilitation interventions that address formulation of appropriate attributions should be considered in conjunction with those targeting self-regulation and executive function for individuals with brain injury.

Studies of neurocognitive aging report altered patterns of brain activity in older versus younger adults performing executive function tasks. We review the extant literature, using activation likelihood estimation meta-analytic methods, to compare age-related differences in the pattern of brain activity across studies examining 2 categories of tasks associated with executive control processing: working memory and inhibition. In a direct contrast of young and older adult activations, older adults engaged bilateral regions of dorsolateral prefrontal cortex as well as supplementary motor cortex and left inferior parietal lobule during working memory. In contrast, age-related changes during inhibitory control were observed in right inferior frontal gyrus and presupplementary motor area. Additionally, when we examined task-related differences within each age group we observed the predicted pattern of differentiated neural response in the younger subjects: lateral prefrontal cortex activity associated with working memory versus right anterior insula/frontal opercular activity associated with inhibition. This separation was largely maintained in older subjects. These data provide the first quantitative meta-analytic evidence that age-related patterns of functional brain change during executive functioning depend on the specific control process being challenged., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Aging is accompanied by declines in executive control abilities and changes in underlying brain network architecture. Here, we examined brain networks in young and older adults during a task-free resting state and an N-back task and investigated age-related changes in the modular network organization of the brain. Compared with young adults, older adults showed larger changes in network organization between resting state and task. Although young adults exhibited increased connectivity between lateral frontal regions and other network modules during the most difficult task condition, older adults also exhibited this pattern of increased connectivity during less-demanding task conditions. Moreover, the increase in between-module connectivity in older adults was related to faster task performance and greater fractional anisotropy of the superior longitudinal fasciculus. These results demonstrate that older adults who exhibit more pronounced network changes between a resting state and task have better executive control performance and greater structural connectivity of a core frontal-posterior white matter pathway.

Abstract Objectives: A common cognitive complaint of older adulthood is distractibility, or decline in ability to concentrate and maintain focus, yet few evidence-based interventions exist to address these deficits. We implemented s pilot trial of an evidence-based executive function training program, to investigate whether training in applied goal-directed attention regulation and problem solving would enhance executive control abilities in a sample of cognitively normal older adults with self-reported complaints of concentration problems. Method: Consecutively recruited participants were placed into small groups and randomized to either Goal-Oriented Attentional Self-Regulation training (GOALS; N = 15) or a closely matched Brain Health Education program (BHE; N = 15). Results: GOALS participants significantly improved on: neurocognitive measures of mental flexibility (p = 0.03, partial eta squared = 0.23); real-world setting functional performance measures of: task failures (p = 0.02, Cohen's d = 0.88), task rule breaks (p = 0.02, Cohen's d = 1.06), and execution (p = 0.04, Cohen's d = 0.76); and in-lab functional assessment of goal-directed behaviour divergent thinking scale (p = 0.03, Cohen's d = 0.95). All participants improved on a neurocognitive measure of planning (p = 0.01, partial eta squared = 0.031). BHE participants' improvement over and above GOALS participants was limited to: rule adherence on the real world task (p = 0.04, Cohen's d = 0.99), and evaluator rating (p = 0.03, Cohen's d = 0.56), and average score (p = 0.02, Cohen's d = 0.71) on the in-lab functional task. Conclusion: Participation in GOALS training can enhance executive control, and lead to real-world functional improvements, for cognitively normal older adults with self-reported attention difficulties. [ABSTRACT FROM AUTHOR]

Creativity refers to the ability to generate novel associations and has been linked to better problem-solving and real-world functional abilities. In younger adults, creative cognition has been associated with functional connectivity among brain networks implicated in executive control [fronto-parietal network (FPN) and salience network (SN)] and associative or elaborative processing default network (DN). Here, we investigate whether creativity is associated with the intrinsic network architecture of the brain and how these associations may differ for younger and older adults. Young (mean age: 24.76, n  = 22) and older (mean age: 70.03, n  = 44) adults underwent multi-echo functional magnetic resonance image scanning at rest and completed a divergent-thinking task to assess creative cognition outside the scanner. Divergent thinking in older adults, compared to young adults, was associated with functional connectivity between the default and both executive control networks (FPN and SN) as well as more widespread default–executive coupling. Finally, the ventromedial prefrontal cortex appears to be a critical node involved in within- and between-network connectivity associated with creative cognition in older adulthood. Patterns of intrinsic network coupling revealed here suggest a putative neural mechanism underlying a greater role for mnemonic processes in creative cognition in older adulthood. [ABSTRACT FROM AUTHOR]

Deficits in attention and executive control are some of the most common, debilitating and persistent consequences of brain injuries. Understanding neural mechanisms that support clinically significant improvements, when they do occur, may help advance treatment development. Intervening via rehabilitation provides an opportunity to probe such mechanisms. Our objective was to identify neural mechanisms that underlie improvements in attention and executive control with rehabilitation training. We tested the hypothesis that intensive training enhances modulatory control of neural processing of perceptual information in patients with acquired brain injuries. Patients (n = 12) participated either in standardized training designed to target goal-directed attention regulation, or a comparison condition (brief education). Training resulted in significant improvements on behavioural measures of attention and executive control. Functional magnetic resonance imaging methods adapted for testing the effects of intervention for patients with varied injury pathology were used to index modulatory control of neural processing. Pattern classification was utilized to decode individual functional magnetic resonance imaging data acquired during a visual selective attention task. Results showed that modulation of neural processing in extrastriate cortex was significantly enhanced by attention regulation training. Neural changes in prefrontal cortex, a candidate mediator for attention regulation, appeared to depend on individual baseline state. These behavioural and neural effects did not occur with the comparison condition. These results suggest that enhanced modulatory control over visual processing and a rebalancing of prefrontal functioning may underlie improvements in attention and executive control. [ABSTRACT FROM AUTHOR]