Motivation and emotional distraction interact and affect executive functions

Previous research on cool-hot executive function (EF) interactions has examined the effects of motivation and emotional distraction on cool EF separately, focusing on one EF component at a time. Although both incentives and emotional distractors have been shown to modulate attention, how they interact and affect cool EF processes is still unclear. Here, we used an experimental paradigm that manipulated updating, inhibition, and shifting demands to determine the interactions of motivation and emotional distraction in the context of cool EF. Forty-five young adults (16 males, 29 females) completed the go/no-go (inhibition), two-back (updating), and task-switching (shifting) tasks. Monetary incentives were implemented to manipulate motivation, and task-irrelevant threatening or neutral faces were presented before the target stimulus to manipulate emotional distraction. We found that incentives significantly improved no-go accuracy, two-back accuracy, and reaction time (RT) switch cost. While emotional distractors had no significant effects on overall task performance, they abolished the incentive effects on no-go accuracy and RT switch cost. Altogether, these findings suggest that motivation and emotional distraction interact in the context of cool EF. Specifically, transient emotional distraction disrupts the upregulation of control activated by incentives. The present investigation has advanced knowledge about the relationship between cool and hot EF and highlights the importance of considering motivation-emotion interactions for a fuller understanding of control.

Executive functioning in antisocial behavior: A multi-level systematic meta-analysis

Neurobiological information - including executive functioning - is increasingly relevant for forensic clinical practice, as well as for the criminal justice system. Previous meta-analyses report that antisocial populations show impaired performance on executive functioning tasks, but these meta-analyses are outdated, have limitations in their methodological approach, and are therefore in need of an update. The current multi-level meta-analysis including 133 studies (2008-2023) confirms impaired performance in executive functioning (d=.42), but studies are heterogeneous. Several moderator analyses showed that neuropsychological test used, type of executive function component, and control group characteristics moderated the overall effect. Specifically, matching psychiatric problems in the non-antisocial control group eliminated any differences in executive functioning between groups. No moderation effects were found for assessment quality, hot or cold executive functions, and various population characteristics. These results could indicate that the assessment of executive functioning in antisocial populations may be less relevant for recidivism risk assessment than thought, although this should first be assessed in prospective longitudinal studies. Executive functioning could potentially be used to identify or screen for individuals with certain treatment needs or be used as a responsivity factor, especially in disorders which are often underdiagnosed in criminal justice settings.

Perseveration and Shifting in Obsessive-Compulsive Disorder as a Function of Uncertainty, Punishment, and Serotonergic Medication

Background

The nature of cognitive flexibility deficits in obsessive-compulsive disorder (OCD), which historically have been tested with probabilistic reversal learning tasks, remains elusive. Here, a novel deterministic reversal task and inclusion of unmedicated patients in the study sample illuminated the role of fixed versus uncertain rules/contingencies and of serotonergic medication. Additionally, our understanding of probabilistic reversal was enhanced through theoretical computational modeling of cognitive flexibility in OCD.

Methods

We recruited 49 patients with OCD, 21 of whom were unmedicated, and 43 healthy control participants matched for age, IQ, and gender. Participants were tested on 2 tasks: a novel visuomotor deterministic reversal learning task with 3 reversals (feedback rewarding/punishing/neutral) measuring accuracy/perseveration and a 2-choice visual probabilistic reversal learning task with uncertain feedback and a single reversal measuring win-stay and lose-shift. Bayesian computational modeling provided measures of learning rate, reinforcement sensitivity, and stimulus stickiness.

Results

Unmedicated patients with OCD were impaired on the deterministic reversal task under punishment only at the first and third reversals compared with both control participants and medicated patients with OCD, who had no deficit. Perseverative errors were correlated with OCD severity. On the probabilistic reversal task, unmedicated patients were only impaired at reversal, whereas medicated patients were impaired at both the learning and reversal stages. Computational modeling showed that the overall change was reduced feedback sensitivity in both OCD groups.

Conclusions

Both perseveration and increased shifting can be observed in OCD, depending on test conditions including the predictability of reinforcement. Perseveration was related to clinical severity and remediated by serotonergic medication.

Effect of acute concurrent exercise training and the mediating role of lactate on executive function: An ERP study

Both acute aerobic (AE) and resistance exercise (RE) have been acknowledged to be effective methods in enhancing executive function and brain-related P3 amplitudes. Nevertheless, the effect of acute concurrent exercise training (CET), combining both AE and RE, on executive function remains subject to speculation. Moreover, investigation of the mechanisms that underlie improvements in executive function would facilitate scientific understanding. Notably, lactate has emerged as a candidate among several potential mechanisms. Therefore, the main aim of the present study was to investigate the effect of acute CET on the cognitive flexibility dimension of executive function using behavioural and neuro-electric measures. A secondary aim was to determine the mediating effect of blood lactate in the acute exercise-executive function relationship. Seventy-eight young adults (38 women, 40 men; 22.8 ± 1.8 years) were randomly assigned to one of the following groups: CET, AE, or reading control (RC). Cognitive flexibility was evaluated using the Task-Switching Test and its derived electroencephalography (EEG) was assessed immediately prior to and following each treatment. Fingertip lactate assays were taken prior to, at the midpoint, and after each treatment. Both acute CET and AE shortened response time regardless of test conditions when compared to the RC group. Greater P3 amplitude was observed following CET in the heterogeneous condition and under AE in the switch condition. A significant mediation of blood lactate for response time emerged in both the CET and AE groups for the heterogeneous and switch conditions. The blood lactate mediation was not reflected in P3 amplitude. The present findings suggest that acute CET leads to positive behavioural and neuro-electric alterations of cognitive flexibility, and its effect is similar to AE. Additionally, blood lactate serves as a mediator of the effects of acute exercise on executive function from a behavioural, but not neuro-electric standpoint.

Executive functions in children with specific learning disorders: Shedding light on a complex profile through teleassessment

Executive Functions (EFs) are high-order cognitive processes relevant to learning and adaptation and frequently impaired in children with specific learning disorders (SLDs). This study aimed to investigate EFs in children with SLD and explore the role of specific EF-related subprocesses, such as stimuli processing and processing speed. Fifty-seven SLD and 114 typically developing (TD) children, matched for gender and age, completed four tasks measuring response inhibition, interference control, shifting, and updating on a web-based teleassessment platform. The results show that SLD children performed lower in all EF tasks than TD children, regardless of stimulus type and condition. Mediation analyses suggested that differences between the SLD and TD groups are mediated by EF-related subprocesses, offering an interpretative model of EF deficits in children with SLD.

Mechanisms of cognitive disinhibition explain individual differences in adult attention deficit hyperactivity disorder traits

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) in adults is strongly associated with psychiatric comorbidity and functional impairment. Here, we aimed to use a newly developed online cognitive battery with strong psychometric properties for measuring individual differences in three cognitive mechanisms proposed to underlie ADHD traits in adults: 1) attentional control - the ability to mobilize cognitive resources to stop a prepotent motor response; 2) information sampling/gathering - adequate sampling of information in a stimulus detection task prior to making a decision; and 3) shifting - the ability to adapt behavior in response to positive and negative contingencies.

METHODS

This cross-sectional and correlational study recruited 650 adults (330 males) aged 18-69 years (M = 33.06; MD = 31.00; SD = 10.50), with previously diagnosed ADHD (n = 329) and those from the general community without a history of ADHD (n = 321). Self-report measures of ADHD traits (i.e., inattention/disorganization, impulsivity, hyperactivity) and the cognitive battery were completed online.

RESULTS

Latent class analysis, exploratory structural equation modeling and factor mixture modeling revealed self-reported ADHD traits formed a unidimensional and approximately normally distributed phenotype. Bayesian structural equation modeling demonstrated that all three mechanisms measured by the cognitive battery, explained unique, incremental variance in ADHD traits, with a total of 15.9% explained in the ADHD trait factor.

CONCLUSIONS

Attentional control and shifting, as well as the less researched cognitive process of information gathering, explain individual difference variance in self-reported ADHD traits with potential to yield genetic and neurobiological insights into adult ADHD.

Effects of short mindful breathing meditations on executive functioning in two randomized controlled double-blinded experiments

While current models of mindfulness propose benefits to the executive functions of inhibition, updating and shifting through mindful breathing meditations, empirical findings on the effects of short mindful breathing meditations are inconclusive regarding their specificity and dose-response relations. Therefore, we compared short mindful breathing meditations (Experiment 1, 45 min over three sessions; Experiment 2, 80 min over four sessions) with relaxation trainings (progressive muscle relaxation; active control) and listening to podcasts (passive control) in two randomized controlled double-blinded trials. Reaction time tasks were used to assess the executive functions of updating (N-Back), inhibition (CPT-II), and shifting (Number-Letter Task). Results of both experiments suggest no mindfulness-specific improvements in executive functions. We conclude that effects following the first stages of mindfulness training may not be specific to the practice or too transient to be reliably measured in pre-post intervention designs. Implications for research in the field are discussed.

Shifting as an executive function separate from updating and inhibition in old age: Behavioral and genetic evidence

This study aimed to examine the organization of executive functions (EFs), specifically working memory updating, prepotent response inhibition, and mental-set shifting in old age, with a particular focus on determining whether the shifting function was behaviorally and genetically separated from the other functions. A total of 248 healthy older Chinese individuals participated, and multiple measures of executive functions were collected. Additionally, measures of fluid intelligence were included to explore the varying relationships between the three executive functions and this higher-order cognitive ability. Furthermore, genetic data were gathered and analyzed to investigate the associations between EFs and six candidate single-nucleotide polymorphisms (SNPs) mapped to dopaminergic, serotonergic, or glutamatergic genes. The results indicated that both the three-factor model and the two-factor model, which combined updating and inhibition, demonstrated a good fit. Furthermore, shifting was found to be behaviorally separated from the other two functions, and the correlation between shifting and fluid intelligence was smaller compared to the correlations between updating and inhibition with fluid intelligence. Moreover, the DRD2 SNPs showed significant associations with shifting, rather than with updating and inhibition. These findings provide evidence that shifting is distinct and separate from updating and inhibition, highlighting the diversity of EFs among older adults.

A true reflection of executive functioning or a representation of task-specific variance? Re-evaluating the unity/diversity framework

The unity/diversity framework, originally published by Miyake et al. (2000) has become the most cited model of executive functioning. Consequently, when researchers operationalise executive function (EF) they often exclusively assess the three "core" EFs: updating, shifting, and inhibition. However, rather than core EFs representing domain general cognitive abilities, these three EFs may instead represent specific procedural skills from the overlapping methodologies of the tasks selected. In this study, we conducted a confirmatory factor analysis (CFA) which showed both the traditional three-factor and nested-factor model from the unity/diversity framework failed to reach satisfactory levels of fit. Subsequently, an exploratory factor analysis supported a three-factor model reflecting: an expanded working memory factor, a combined shifting/inhibition factor representing cognitive flexibility, and a factor comprised solely of the Stroop task. These results demonstrate that working memory remains the most robustly operationalised EF construct, whereas shifting and inhibition may represent task-specific mechanisms of a broader domain-general cognitive flexibility factor. Ultimately, there is little evidence to suggest that updating, shifting, and inhibition encapsulates all core EFs. Further research is needed to develop an ecologically valid model of executive functioning that captures the cognitive abilities associated with real world goal-directed behaviour.

Do executive functions predict physical activity behavior? A meta-analysis

BACKGROUND

Executive functions (EFs) are important determinants of health behaviors. In the present study, a meta-analysis was conducted to investigate the relationship between EFs and physical activity (PA) behavior.

METHODS

Systematic searches were carried out in PsycInfo, MEDLINE, and SPORTDiscus databases throughout April 2021. Prospective empirical studies conducted with general healthy populations across the lifespan, which reported the relationship between baseline EFs and later PA behavior were selected.

RESULTS

Eight studies were found eligible. Results of the multilevel meta-analysis revealed a small but significant total effect size for EFs on PA behavior of z = 0.12. High heterogeneity was observed among studies. When potential moderators were tested, residual heterogeneity remained significant and the effects of the moderators were not significant. The effect size dropped when accounted for publication bias.

CONCLUSIONS

Despite limitations, the study provided evidence for EFs' determinant role on PA behavior. More research is however encouraged to inform PA promotion programs that are well-prepared for individual differences in EFs.

A Green's Function Approach for Determining Surface Induced Broadening and Shifting of Molecular Energy Levels

Upon adsorption of a molecule onto a surface, the molecular energy levels (MELs) broaden and change their alignment. This phenomenon directly affects electron transfer across the interface and is, therefore, a fundamental observable that influences electrochemical device performance. Here, we propose a rigorous parameter-free framework, built upon the theoretical construct of Green's functions, for studying the interface between a molecule and a bulk surface and its effect on MELs. The method extends beyond the usual wide-band limit approximation, and its generality allows its use with any level of electronic structure theory. We demonstrate its ability to predict the broadening and shifting of MELs as a function of intramolecular coupling, molecule/surface coupling, and the surface density of states for a molecule with two MELs adsorbed on a one-dimensional model metal surface. The new approach could help provide guidelines for the design and experimental characterization of electrochemical devices with optimal electron transport.

Effects of Acute Resistance Exercise on Executive Function: A Systematic Review of the Moderating Role of Intensity and Executive Function Domain

BACKGROUND

Research has demonstrated that there is a beneficial effect of acute exercise on cognitive function; however, the moderators of the acute resistance exercise (RE) effect on executive function (EF) are underestimated. This systematic review aims to clarify the effects of acute RE on EF by examining the moderating effect of exercise intensity (light, moderate, and vigorous) and EF domains (inhibitory control, working memory, and cognitive flexibility), as well as their interactions.

METHODS

The search strategy was conducted in four databases (PubMed, Scopus, PsycARTICLES, and Cochrane Library) prior to January 29, 2022. Included studies had to: (1) investigate acute RE in adults with normal cognition and without diagnosed disease; (2) include a control group or control session for comparison; (3) include outcomes related to the core EF domains; and (4) be published in English. The methodological quality of the included studies was judged according to the PEDro scale guidelines.

RESULTS

Nineteen studies were included which included a total of 692 participants. More than half of the outcomes (24/42, 57.14%) indicate that acute RE had a statistically significant positive effect on overall EF. In terms of RE intensity and EF domain, moderate intensity acute RE benefited EF more consistently than light and vigorous intensity acute RE. Acute RE-induced EF benefits were more often found for inhibitory control than for working memory and cognitive flexibility. When considering moderators simultaneously, measuring inhibitory control after light or moderate intensity RE and measuring working memory or cognitive flexibility after moderate intensity RE most often resulted in statistically significant positive outcomes.

CONCLUSION

Acute RE has a beneficial effect on EF, observed most consistently for inhibitory control following moderate intensity RE. Future studies should include all exercise intensities and EF domains as well as investigate other potential moderators to enable a better understanding of the benefits of acute RE on EF.

Inhibition, Shifting and Updating: Inter and intra-domain commonalities and differences from an executive functions activation likelihood estimation meta-analysis

Executive functions are higher-order mental processes that support goal-directed behavior. Among these processes, Inhibition, Updating, and Shifting have been considered core executive domains. In this meta-analysis, we comprehensively investigate the neural networks of these executive domains and we synthesize for the first time the neural convergences and divergences among the most frequently used executive paradigms within those domains. A systematic search yielded 1055 published neuroimaging studies (including 26,191 participants in total). Our study revealed that a fronto-parietal network was shared by the three main domains. Furthermore, we executed conjunction analyses among the paradigms of the same domain to extract the core distinctive components of the main executive domains. This approach showed that Inhibition and Shifting are characterized by a strongly lateralized neural activation in the right and left hemisphere, respectively. In addition, both networks overlapped with the Updating network but not with each other. Remarkably, our study detected heterogeneity among the paradigms from the same domain. More specifically, analysis of Inhibition tasks revealed differing activations for Response Inhibition compared to Interference Control paradigms, suggesting that Inhibition encompasses relatively heterogeneous sub-functions. Shifting analyses revealed a bilateral overlap of the Wisconsin Card Sorting Task with the Updating network, but this pattern was absent for Rule Switching and Dual Task paradigms. Moreover, our Updating meta-analyses revealed the neural signatures associated with the specific modules of the Working Memory model from Baddeley and Hitch. To our knowledge, this is the most comprehensive meta-analysis of executive functions to date. Its paradigm-driven analyses provide a unique contribution to a better understanding of the neural convergences and divergences among executive processes that are relevant for clinical applications, such as cognitive enhancement and neurorehabilitation interventions.

Virtual Reality-based Cognitive Intervention for Enhancing Executive Functions in Community-dwelling Older Adults

With the rapid growth of the older population globally, it is anticipated that age-related cognitive decline in the prodromal phase and more severe pathological decline will increase. Moreover, currently, no effective treatment options for the disease exist. Thus, early and timely prevention actions are promising and prior strategies to preserve cognitive functions by preventing symptomatology from increasing the age-related deterioration of the functions in healthy older adults. This study aims to develop the virtual reality-based cognitive intervention for enhancing executive functions (EFs) and examine the EFs after training with the virtual reality-based cognitive intervention in community-dwelling older adults. Following inclusion/exclusion criteria, 60 community-dwelling older adults aged 60-69 years were involved in the study and randomly divided into passive control and experimental groups. Eight 60 min virtual reality-based cognitive intervention sessions were held twice a week and lasted for 1 month. The EFs (i.e., inhibition, updating, and shifting) of the participants were assessed by using standardized computerized tasks, i.e., Go/NoGo, forward and backward digit span, and Berg's card sorting tasks. Additionally, a repeated-measure ANCOVA and effect sizes were applied to investigate the effects of the developed intervention. The virtual reality-based intervention significantly improved the EFs of older adults in the experimental group. Specifically, the magnitudes of enhancement were observed for inhibitory as indexed by the response time, F(1) = 6.95, p < .05, η_p² = .11, updating as represented by the memory span, F(1) = 12.09, p < .01, η_p² = .18, and the response time, F(1) = 4.46, p = .04, η_p² = .07, and shifting abilities as indexed by the percentage of correct responses, F(1) = 5.30, p = .03, η_p² = .09, respectively. The results indicated that the simultaneous combined cognitive-motor control as embedded in the virtual-based intervention is safe and effective in enhancing EFs in older adults without cognitive impairment. Nevertheless, further studies are required to investigate the benefits of these enhancements to motor functions and emotional aspects relating to daily living and the well-being of older populations in communities.

The contribution of latent factors of executive functioning to mind wandering: an experience sampling study

Accumulating evidence suggests that individuals with greater executive resources spend less time mind wandering. Independent strands of research further suggest that this association depends on concentration and a guilty-dysphoric daydreaming style. However, it remains unclear whether this association is specific to particular features of executive functioning or certain operationalizations of mind wandering, including task-unrelated thoughts (TUTs, comprising external distractions and mind wandering) and stimulus-independent and task-unrelated thoughts (SITUTs, comprising mind wandering only). This study sought to clarify these associations by using confirmatory factor analysis to compute latent scores for distinct executive functions based on nine cognitive tasks and relating them to experience sampling reports of mind wandering. We expected that individuals with greater executive control (specifically updating) would show a stronger reduction in SITUTs as momentary concentration and guilty-dysphoric style increase. A bifactor model of the cognitive battery indicated a general factor (common executive functioning) and ancillary factors (updating and shifting). A significant interaction between updating and concentration on mind wandering was observed with mind wandering defined as TUTs, but not as SITUTs (N = 187). A post hoc analysis clarified this discrepancy by showing that as concentration increases, both external distractions and mind wandering decrease more strongly among people with greater updating. Moreover, common executive functioning predicted a more negative slope of guilty-dysphoric style on SITUTs, whereas updating and shifting predicted more positive slopes. The opposite slopes of these executive functions on daily life mind wandering may reflect a stability-flexibility trade-off between goal maintenance and goal replacement abilities.

Attentional orienting abilities in bilinguals: Evidence from a large infant sample

A key question in studies of cognitive development is whether bilingual environments impact higher-cognitive functions. Inconclusive evidence in search of a "bilingual cognitive advantage" has sparked debates on the reliability of these findings. Few studies with infants have examined this question, but most of them include small samples. The current study presents evidence from a large sample of 6- and 10-month-old monolingual- and bilingual-exposed infants (N = 152), which includes a longitudinal subset (n = 31), who completed a cueing attentional orienting task. The results suggest bilingual infants showed significant developmental gains in latency performance during the condition that was most cognitively demanding (Incongruent). The results also revealed bilingual infants' performance was associated with their parents' dual-language switching behavior. Taken together, these results provide support that bilingual experiences (i.e., dual-language mixing) influence infants' shifting and orienting of attention.

Task-switching abilities in episodic and chronic migraine

Migraineurs show impaired cognitive functions interictally, mainly involving information processing speed, basic attention, and executive functions. We aimed to assess executive impairment in migraine patients with different attack frequencies through a task-switching protocol designed to assess different sub-processes of executive functioning. We enrolled 42 migraine patients and divided them into three groups based on the attack frequency: 13 subjects had episodic migraine with a low frequency (LFEM, 4-7 migraine days per month), 14 subjects had high-frequency episodic migraine (HFEM, 8-14 days) and, finally, 15 subjects presented chronic migraine (≥ 15 headache days/month, CM); we compared them to 20 healthy control (HC), matched to both gender and education. Patients with high headache frequencies (CM and HFEM) showed worse performance than LFEM and HC controls, as indicated by poor accuracy, increased switch cost, and reaction times. Our study demonstrated a difference in task-switching abilities in patients with high frequency or chronic migraine compared with low-frequency episodic migraine and healthy controls. These difficulties in executive control processes could be related to altered functioning of the frontal cortex and its cortical and subcortical connections.

A meta-analysis of the executive function components inhibition, shifting, and attention in intellectual disabilities

BACKGROUND

Executive function is a concept for higher-order cognitive functions, which have the role of controller and modulator of cognitive abilities. The consensus in the literature is that people with an intellectual disability perform significantly lower on executive function tasks than groups matched on chronological age. The comparison with groups matched on mental age is less clear. Therefore, the objective of this meta-analysis was to investigate to what extent executive function is impaired in people with intellectual disability compared with a typically developing control group matched on mental age. It was also investigated if the executive function component and intellectual disability aetiology moderated the effect.

METHODS

Eligibility criteria were participants with intellectual disability (IQ ≤ 75) without a dual diagnosis; a comparison group matched on mental age; executive function outcome reported in a group comparison study design with n ≥ 10. Working memory tasks and ratings of executive function were not included. The literature search yielded 6637 potentially interesting articles. Twenty-six studies (with 99 effect sizes) including 1395 participants were included in the quantitative synthesis.

RESULTS

A multilevel random-effects meta-analysis found that people with intellectual disability performed statistically significantly lower than the mental age-matched group on the executive function tasks, g = -0.34, 95% confidence interval = [-0.53, -0.16]. However, the heterogeneity between effect sizes was large. The intellectual disability aetiology moderator was significant, but it only reduced the heterogeneity marginally.

CONCLUSION

The overall conclusion is that individuals with an intellectual disability have more problems with executive function tasks than mental age-matched controls. Limitations are the large unexplained variance and the remarkably high number (69) of different tests that were used, which make more detailed conclusions problematic. This meta-analysis implies that future studies need to be of better quality, to have higher power, and to a higher degree use the same executive function tests.

Shifting from vitamin K antagonists to non-vitamin K antagonist oral anticoagulants in patients with atrial fibrillation: predictors, patterns and temporal trends

Background

Non-Vitamin K antagonist oral anticoagulants (NOACs) emerged as an alternative with comparable or superior efficacy and safety to vitamin K antagonists (VKAs) for stroke prevention in patients with non-valvular atrial fibrillation (AF).

Objectives

The aim of the current study was to investigate the patterns, predictors, timelines and temporal trends of shifting from VKAs to NOACs.

Methods

In this retrospective observational study, the computerized database of a large healthcare provider in Israel, Maccabi Healthcare Services, was searched to identify patients with AF for whom either a VKA or NOAC was prescribed between 2012 and 2015. Time from diagnosis to therapy initiation and to shifting between therapies was evaluated.

Results

Out of 6987 eligible AF incident patients, 2338 (33.4%) initiated treatment with a VKA and 2221 (31.7%) with a NOAC. In addition, 5259 prevalent patients were analyzed. During the study period, NOAC prescriptions proportion among the newly diagnosed cases increased from 32 to 68.4% (p for trend <  0.001). The median time from diagnosis to first dispensing was greater in NOAC than VKA and decreased among patients treated with NOAC during the study period (2012: 1.9 and 0.3 months, 2015: 0.7 and 0.2 months, respectively). During follow-up, 3737 (49%) patients (54.3% and 47.1% of the incident and prevalent cases, respectively), shifted from a VKA to a NOAC, after a median of 22 months and 39 months in the incident and prevalent cases, respectively, decreasing throughout the study period. Female gender, younger age, southern district, higher CHADS₂ and CHA₂DS₂-VASC score, non-smoking, and treatment with antiplatelets were associated with a greater likelihood for therapy shift. Shifting from a NOAC to a VKA decreased over time from 8 to 4.5% in 2012 to 0.5% and 0.7% in 2015 in the incident and prevalent groups, p <  0.001 respectively.

Conclusions

Shifting from VKA to NOAC occurred in 50% of the cases, more frequently among incident cases, and younger patients with greater stroke risk. Shifting from a NOAC to a VKA was much less frequent, yet it occurred more often in incident cases and decreased over time. A socially and economically sensitive program to optimize the initiation of OAC therapy upon diagnosis is warranted.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02295-w.

The relationship between executive functioning and repetitive negative thinking in youth: A systematic review of the literature

Repetitive negative thinking (RNT) and executive functioning (EF) deficits are each characteristic of many forms of youth psychopathology. Extensive work has examined the relationship between rumination, a form of RNT, and EF in adults. However, less is known about the relationship between RNT more broadly and EF in youth, for whom these constructs are developing and emerging. Here, we systematically and qualitatively reviewed 27 studies on the associations between EF (e.g., shifting, inhibition, working memory) and RNT (e.g., rumination, worry, obsessions) in youth. All forms of RNT were more commonly positively associated with questionnaire-reported EF problems in daily life, most frequently in the domain of shifting. Task-based assessments of EF were less consistently associated with RNT in youth, with no strong pattern of presence vs. absence of associations. Further, limited longitudinal work has been conducted on this topic to date. This review integrates initial work with regard to RNT and EF deficits in a still-developing population, and discusses clear future need for longitudinal, multi-method assessments of the relationship between RNT and EF subtypes in youth.

Effects of foreign language learning on executive functions in healthy older adults: study protocol for a randomised controlled trial

Background

With age, most cognitive functions decline. As the number of people aged 60 years and older is expected to rise rapidly within the next decades, identifying interventions that promote healthy cognitive ageing is of utmost importance. Promising research on bilingualism has led to the notion that learning a foreign language could protect against cognitive decline. Foreign language learning likely promotes executive functions, which are higher-order cognitive abilities particularly affected by age-related cognitive decline. However, evidence is still sparse and has produced contradictory results. This study aims to investigate the effects of short and intensive foreign language learning on executive functions in healthy older adults.

Methods

In a randomised controlled trial, we will assign 60 native German-speaking monolingual healthy older adults, aged 65–80 years, to either a foreign language learning or a waiting list control group. Language learners will attend a face-to-face, group-based Spanish course for beginners for 1.5 h a day, 5 days a week, for a total of 3 weeks. Cognitive performance in executive functions will be assessed before and after the intervention or after a waiting period of 3 weeks (waiting list control group). Participants will be tested again after 3 months to evaluate longitudinal effects of foreign language learning. The waiting list control group will receive Spanish lessons only after the final assessment and will be invited to an additional voluntary evaluation after completion of the course.

Discussion

To the best of our knowledge, we are conducting the first randomised controlled trial on the effects of short and intensive foreign language learning in older adulthood on executive functions. Enhanced cognitive performance after foreign language learning would indicate that learning a foreign language could enlarge cognitive reserve and thus promote healthy cognitive ageing in older adults.

Trial registration

German Clinical Trials Register DRKS00016552. Registered on 11 February 2019.

Examining the latent structure of emotional awareness and associations with executive functioning and depression

Emotional awareness is comprised of dispositions towards and knowledge about one's emotions. Executive functions (EF) are cognitive processes that organise and guide behaviour towards one's goals. Both emotional awareness and EF play a role in processes such as emotion regulation and are risk factors for the development and maintenance of depression. Although previous research suggests that aspects of emotional awareness are related to EF, methodological and measurement limitations within the available literature make it difficult to clearly understand how they are associated. In this registered report, we examined the extent to which task-based measures of a specific EF process, shifting, are differentially related to unique facets of emotional awareness (i.e. emotional clarity of type, emotional clarity of source, voluntary attention to emotions, and involuntary attention to emotions), and to what extent EF and emotional awareness are related to depression. Using structural equation modelling, we found evidence that emotional clarity of type was associated with greater shifting cost. Shifting was not associated with any other facet of emotional awareness. Depression was linked to lower emotional clarity of type, higher involuntary attention to emotions, but not poorer EF performance. We discuss how emotional awareness and EF may be uniquely related to depression.

Executive function in Down syndrome: A meta-analysis

BACKGROUND

Executive function (EF) refers to a set of cognitive processes involved in goal-oriented behavior-especially inhibition, attention shifting, and working memory. EF has been identified as a probable area of difficulty in Down syndrome (DS), but the exact nature of the difficulty has not been well-established.

AIMS

The meta-analysis sought to confirm or disconfirm EF as an area of difficulty in DS and elucidate an EF profile.

METHODS AND PROCEDURES

A random-effects meta-analysis was conducted on 57 studies that compared a group with DS to a typically developing (TD) mental age matched group on one or more executive function tasks. Heterogeneity was examined and moderators analyzed.

OUTCOMES AND RESULTS

The overall mean weighted effect size was large (d = -0.87), indicating poorer EF in groups with DS vs TD groups. Heterogeneity was significant, and moderator analysis revealed an EF profile with a very large effect for verbal WM/STM, a large effect for shifting, and moderate effects for inhibition and nonverbal WM/STM. Skewness analysis suggested that mean effect sizes might have been dampened, especially for WM/STM and shifting.

CONCLUSIONS AND IMPLICATIONS

Individuals with DS display a pronounced difficulty in EFs; implications for interventions and future research are discussed.

Influence of a Planning Intervention on Physical Activity Behavior: the Moderating Role of Intentions and Executive Functions in a Randomized Controlled Trial

Background

Planning and executive functions (EFs; inhibition, updating, shifting) are self-regulatory variables that help people to become and stay physically active. The aim of this study was to examine how and for whom a planning intervention affects physical activity (PA) behavior in the short term. Therefore, the mediating role of planning and the moderating role of intentions and EFs for the planning–behavior link were examined.

Method

In a randomized control trial with two treatment groups (planning group vs. control group) and two points of measurement (t1 and t2, 1 week apart), n = 200 students participated in both measurements. At t1, participants filled in standardized questionnaires assessing PA behavior, intention, and planning. Computer-based tests assessed the following EFs: inhibition, updating, and shifting. At t2, planning and PA behavior were measured again. Moderated mediation analyses were conducted.

Results

A significant increase in PA between t1 and t2 was found for the planning group compared with the control group. Furthermore, planning cognitions significantly mediated the effect of the planning group on behavior and intention, as well as the EF updating moderated the association between planning and behavior. Forming plans was particularly beneficial for participants with high intentions and lower updating performance.

Conclusion

Planning enhances PA behavior, particularly when PA intention is high. Poor performance in updating can be compensated by planning since encouraging people to generate plans might facilitate automatic enactment of the behavior.

Individual differences impact memory for a crime: A study on executive functions resources

Previous studies demonstrated that memory accuracy is affected by the availability of the individual's cognitive resources. A predominant role in complex cognition has been postulated for executive functions (EF). The aim of the present study was to verify if there are differences in remembering a crime with respect to the individual's EF availability (i.e., Shifting, Inhibition, and Updating). We showed participants a video of a violent crime. Next, they were requested to imagine to be an eyewitness of the crime and report a testimony as detailed as possible. A subsequent memory test was run after ten days. EF resources were assessed in a third session through three neuropsychological tasks. Findings showed that high EF individuals reported more correct details and fewer memory distortions (i.e., omissions and commissions) than low EF individuals. Our results underline that individual EF resources are implicated in the recalling of an event.

Executive Functioning Heterogeneity in Pediatric ADHD

Neurocognitive heterogeneity is increasingly recognized as a valid phenomenon in ADHD, with most estimates suggesting that executive dysfunction is present in only about 33%-50% of these children. However, recent critiques question the veracity of these estimates because our understanding of executive functioning in ADHD is based, in large part, on data from single tasks developed to detect gross neurological impairment rather than the specific executive processes hypothesized to underlie the ADHD phenotype. The current study is the first to comprehensively assess heterogeneity in all three primary executive functions in ADHD using a criterion battery that includes multiple tests per construct (working memory, inhibitory control, set shifting). Children ages 8-13 (M = 10.37, SD = 1.39) with and without ADHD (N = 136; 64 girls; 62% Caucasian/Non-Hispanic) completed a counterbalanced series of executive function tests. Accounting for task unreliability, results indicated significantly improved sensitivity and specificity relative to prior estimates, with 89% of children with ADHD demonstrating objectively-defined impairment on at least one executive function (62% impaired working memory, 27% impaired inhibitory control, 38% impaired set shifting; 54% impaired on one executive function, 35% impaired on two or all three executive functions). Children with working memory deficits showed higher parent- and teacher-reported ADHD inattentive and hyperactive/impulsive symptoms (BF₁₀ = 5.23 × 10⁴), and were slightly younger (BF₁₀ = 11.35) than children without working memory deficits. Children with vs. without set shifting or inhibitory control deficits did not differ on ADHD symptoms, age, gender, IQ, SES, or medication status. Taken together, these findings confirm that ADHD is characterized by neurocognitive heterogeneity, while suggesting that contemporary, cognitively-informed criteria may provide improved precision for identifying a smaller number of neuropsychologically-impaired subtypes than previously described.

Cognitive control deficits in pediatric frontal lobe epilepsy

Executive dysfunction and behavioral problems are common in children with epilepsy. Inhibition and shifting, both aspects of cognitive control, seem related to behavior problems and are thought to be driven mainly by the frontal lobes. We investigated if inhibition and shifting deficits are present in children with frontal lobe epilepsy (FLE). Secondly, we studied the relationship between these deficits and behavior problems. Thirty-one children were administered the Stroop Color Word Test and a digital version of the Wisconsin Card Sorting Test (WCST). Parents completed the Behavioral Rating Inventory for Executive Function (BRIEF) and the Achenbach scale (Child Behavior Checklist (CBCL)). About 20% of the children displayed significant low results on the Stroop Effect. About 60% showed shifting problems on the WCST. Parents reported cognitive control and behavioral deficits in about a third of the children. Also, behavioral problems and deficits in inhibition and shifting in daily life (BRIEF) seem to be related. There were no correlations between questionnaires and the Stroop and the WCST. Only in the group of children with many perseverative errors there were especially high correlations between Inhibit of the BRIEF.

Building functional connectivity neuromarkers of behavioral self-regulation across children with and without Autism Spectrum Disorder

Behavioral self-regulation develops rapidly during childhood and struggles in this area can have lifelong negative outcomes. Challenges with self-regulation are common to several neurodevelopmental conditions, including Autism Spectrum Disorder (ASD). Little is known about the neural expression of behavioral regulation in children with and without neurodevelopmental conditions.

We examined whole-brain brain functional correlations (FC) and behavioral regulation through connectome predictive modelling (CPM). CPM is a data-driven protocol for developing predictive models of brain–behavior relationships and assessing their potential as ‘neuromarkers’ using cross-validation. The data stems from the ABIDE II and comprises 276 children with and without ASD (8–13 years).

We identified networks whose FC predicted individual differences in behavioral regulation. These network models predicted novel individuals’ inhibition and shifting from FC data in both a leave-one-out, and split halves, cross-validation. We observed commonalities and differences, with inhibition relying on more posterior networks, shifting relying on more anterior networks, and both involving regions of the DMN.

Our findings substantially add to our knowledge on the neural expressions of inhibition and shifting across children with and without a neurodevelopmental condition. Given the numerous behavioral issues that can be quantified dimensionally, refinement of whole-brain neuromarker techniques may prove useful in the future.

Location-Scale Models in Demography: A Useful Re-parameterization of Mortality Models

Several parametric mortality models have been proposed to describe the age pattern of mortality since Gompertz introduced his "law of mortality" almost two centuries ago. However, very few attempts have been made to reconcile most of these models within a single framework. In this article, we show that many mortality models used in the demographic and actuarial literature can be re-parameterized in terms of a general and flexible family of models, the family of location-scale (LS) models. These models are characterized by two parameters that have a direct demographic interpretation: the location and scale parameters, which capture the shifting and compression dynamics of mortality changes, respectively. Re-parameterizing a model in terms of the LS family has several advantages over its classic formulation. In addition to aiding parameter interpretability and comparability, the statistical estimation of the LS parameters is facilitated due to their significantly lower correlation. The latter, in turn, further improves parameter interpretability and reduces estimation bias. We show the advantages of the LS family over the typical parameterization of mortality models with two illustrations using the Human Mortality Database.

Executive Functions and Symptom Severity in an Italian Sample of Intellectually Able Preschoolers with Autism Spectrum Disorder

A novel battery (BAFE; Valeri et al. 2015) was used in order to assess three executive function (EF) abilities (working memory, inhibition and shifting) in a sample of 27 intellectually able preschoolers with autism spectrum disorder (ASD) compared with 27 typically developing children matched on age and nonverbal IQ. Differences in EF skills were analyzed in participants with distinct ASD symptom severity. Children with ASD performed worse than typical controls on both set-shifting and inhibition, but not on visuo-spatial working memory. Additionally, children with more severe ASD symptoms showed a worse performance on inhibition than children with milder symptoms. These results confirm the presence of EF deficits and highlight a link between ASD symptoms and EF impairments in preschool age.

Examining differential relationships among self-reported attentional control, depression, and anxiety in a transdiagnostic clinical sample

BACKGROUND

Poor attentional control, defined as difficulty focusing attention on a task or shifting attention flexibly between tasks, is a transdiagnostic construct theorized to confer risk for, and maintain, depression and anxiety. Research to date in non-clinical samples has suggested a dissociable relationship between the two factors of self-reported attentional control and psychopathology, with depression being associated with difficulties shifting and anxiety being associated with focusing. However, to our knowledge no study has tested this differential set of relationships in a clinical sample.

METHODS

Adults (N = 493) presenting for psychiatric treatment completed measures of depressive and anxiety symptom severity and self-reported attentional control. Hierarchical linear regression and Zou's (2007) confidence interval method were used to examine the relationship between clinical symptoms and attentional control.

RESULTS

Both shifting and focusing were significantly correlated with anxiety and depressive symptoms in this sample. However, focusing was more strongly associated with clinical symptomatology than shifting, which showed a weak correlation.

LIMITATIONS

All constructs were measured cross-sectionally by self-report questionnaires.

CONCLUSIONS

In contrast to studies conducted in non-clinical samples, attentional focusing appears to be more relevant than attentional shifting in a clinical sample for both depression and anxiety symptoms. These findings lend support to efforts to develop neurocognitive interventions that improve focusing. Replication of these findings, particularly in longitudinal studies, is warranted.

Which tasks measure what? Reflections on executive function development and a commentary on Podjarny, Kamawar, and Andrews (2017)

This article provides a selective review of the literature on executive function development and related topics, focusing on the conceptual and terminological confusions that might hinder communication among researchers in the field. The distinctions between working memory and updating, and between shifting and flexibility, are discussed. Methodological problems, which have implications regarding whether a certain task can be considered a measure of a psychological construct, are also discussed. Research on preschoolers is examined with particular attention because it is a rapidly growing but controversial field that seems in particular need of greater conceptual clarity. As a specific touchstone case, we discuss whether the Multidimensional Card Selection Task (MCST) created by Podjarny, Kamawar, and Andrews (2017) should better be considered a measure of concurrent cognitive flexibility or working memory capacity. It is argued that connecting tasks to theoretical constructs is not warranted unless based on rigorous empirical testing of well-formulated models.

The shifting self in aging

BACKGROUND AND AIMS

This study investigated the ability of older adults to shift between self-images.

METHODS

We designed a shifting-self task in which older adults and younger adults were invited to produce statements describing their physical self (e.g., "I am tall") and psychological self (e.g., "I am cheerful"). Participants were invited to shift between physical-self statements and psychological-self statements and, on a control task, to produce two blocks of physical-self statements and psychological-self statements. They also performed a typical shifting task (i.e., the plus-minus task).

RESULTS

Analysis showed slower completion time on the shifting-self task in older adults than in younger adults. Time to complete the shifting-self task was longer than that for the control task in both older and younger adults. Performances on the shifting-self task were significantly correlated with performances on the plus-minus task.

DISCUSSION

We hypothesized that older adults take more time to shift between self-images because they enjoy self-stability. In other words, the tendency of older adults to shift between self-images more slowly than younger adults might be because they have more consistent or stable self-concepts, and are therefore less inclined to "change" their self-images.

Task-switching abilities in pre-manifest Huntington's disease subjects

INTRODUCTION

Huntington's Disease (HD) cognitive dysfunction occurs before unequivocal motor signs become apparent. The predominant early cognitive abnormal domains may include deficits in psychomotor speed, negative emotion recognition and executive functioning. Our study is aimed to investigate the executive control of cognition in pre-manifest (pre) HD subjects, by means of a task-switching protocol.

METHODS

We recruited 30 pre-HD subjects and 18 age-, sex- and education-matched Healthy Controls (HC). Subjects were assigned to two experimental groups: 15 pre-HD1 with a Total Motor Score (TMS) ≤4 (far from onset) and 15 pre-HD2 with a 5 ≤ TMS≤9 (near to onset and Diagnostic Confidence Level (DCL) still<4). Two different tasks were performed in rapid and random succession, so that the task was either changed from one trial to the next one (switch trials) or repeated (repetition trials). Switch trials are usually slower than repetitions, causing a so-called Switch Cost (SC).

RESULTS

Pre-HD subjects had worse performance than HC in the switch and repetition trials, as indicated by increased SC and reaction times. In particular, pre-HD2 showed impaired switching abilities with reaction times slower than pre-HD1 and HC.

CONCLUSIONS

Our study highlighted a task-switching impairment since HD was still at a pre-manifest stage. Such abnormalities worsen when pre-HD subjects start to show subtle motor manifestations, still nonspecific and insufficient to define the clinical diagnosis of HD (DCL<4). Considering that such abilities have obvious implications for activities of daily living, early cognitive rehabilitation programs addressing such deficits might be useful in the premanifest stage of the disease.

Attentional control deficits in social anxiety: Investigating inhibition and shifting functions using a mixed antisaccade paradigm

BACKGROUND AND OBJECTIVES

Attentional control has recently been assumed to play a critical role in the generation and maintenance of threat-related attentional bias and social anxiety. The present study aimed to investigate whether socially anxious (SA) individuals show impairments in attentional control functions, particularly in inhibition and shifting.

METHODS

Forty-two SA and 41 non-anxious (NA) participants completed a mixed antisaccade task, a variant of the antisaccade task that is used to investigate inhibition as well as shifting functions.

RESULTS

The results showed that, overall, SA participants had longer antisaccade latencies than NA participants, but the two groups did not differ in their antisaccade error rates. Moreover, in the single-task block, SA participants had longer latencies than NA participants for antisaccade but not prosaccade trials. In the mixed-task block, the SA participants had longer latencies than the NA participants for both task types. The two groups did not differ in their latency switch costs in the mixed-task blocks.

LIMITATIONS

First, this study was conducted using a non-clinical sample of undergraduate students. Second, the antisaccade task measures primarily oculomotor inhibition. Third, this study did not include the measure of state anxiety to rule out the effects of state anxiety on the present findings.

CONCLUSIONS

This study suggests that SA individuals demonstrate diminished efficiency of inhibition function but show no significant impairment of shifting function. However, in the mixed-task condition, SA individuals may exhibit an overall reduction in processing efficiency due to the higher task difficulty.

Internal shifting impairments in response to emotional information in dysphoric adolescents

BACKGROUND AND OBJECTIVES

Previous studies have suggested that internal cognitive control impairments may play an important role in the development of depression. Despite a growing body of research in adults, the ability to shift internal attention between mental representations in working memory has received little attention in younger populations. This study investigated internal shifting capacity between emotional and non-emotional information in dysphoric and non-dysphoric adolescents.

METHODS

Twenty dysphoric and 34 non-dysphoric adolescents (10-17 years) completed an Internal Shifting Task, with pictures of angry and neutral faces, to measure the ability to shift attention between information held in working memory.

RESULTS

Dysphoric adolescents showed specific shifting impairments when processing emotional material relative to non-dysphoric adolescents. Valence-specific analyses revealed that shifting was particularly impaired when shifting from negative to neutral information. By comparison, relative to non-dysphoric adolescents, dysphoric adolescents did not show shifting impairments when non-emotional features of the pictures had to be processed.

LIMITATIONS

The study is limited by the absence of a structured clinical interview as dysphoria was determined dimensionally. Furthermore, a comparison of the effects of different negative stimuli on shifting could not be made since sad stimuli were not included in the stimulus set.

CONCLUSIONS

The results confirm the link between depressive symptoms and emotion-specific shifting impairments in adolescents and indicate that targeting shifting ability in response to emotional stimuli may be a promising avenue for prevention programs. Longitudinal research is needed to replicate results and to explore the role of internal shifting impairments in the etiology and maintenance of depression.

Anticipatory processing in social anxiety: Investigation using attentional control theory

BACKGROUND AND OBJECTIVES

Cognitive models of social anxiety disorder (SAD) emphasize anticipatory processing as a prominent maintaining factor occurring before social-evaluative events. While anticipatory processing is a maladaptive process, the cognitive mechanisms that underlie ineffective control of attention are still unclear. The present study tested predictions derived from attentional control theory in a sample of undergraduate students high and low on social anxiety symptoms.

METHODS

Participants were randomly assigned to either engage in anticipatory processing prior to a threat of a speech task or a control condition with no social evaluative threat. After completing a series of questionnaires, participants performed pro-saccades and antisaccades in response to peripherally presented facial expressions presented in either single-task or mixed-task blocks.

RESULTS

Correct antisaccade latencies were longer than correct pro-saccade latencies in-line with attentional control theory. High socially anxious individuals who anticipated did not exhibit impairment on the inhibition and shifting functions compared to high socially anxious individuals who did not anticipate or low socially anxious individuals in either the anticipatory or control condition. Low socially anxious individuals who anticipated exhibited shorter antisaccade latencies and a switch benefit compared to low socially anxious individuals in the control condition.

LIMITATIONS

The study used an analogue sample; however findings from analogue samples are generally consistent with clinical samples.

CONCLUSIONS

The findings suggest that social threat induced anticipatory processing facilitates executive functioning for low socially anxious individuals when anticipating a social-evaluative situation.

On the relationship between executive functions of working memory and components derived from fluid intelligence measures

The aim of the current study is to provide new insights into the relationship between executive functions and intelligence measures in considering the item-position effect observed in intelligence items. Raven's Advanced Progressive Matrices (APM) and Horn's LPS reasoning test were used to assess fluid intelligence which served as criterion in investigating the relationship between intelligence and executive functions. A battery of six experimental tasks measured the updating, shifting, and inhibition processes of executive functions. Data were collected from 205 university students. Fluid intelligence showed substantial correlations with the updating and inhibition processes and no correlation with the shifting process without considering the item-position effect. Next, the fixed-link model was applied to APM and LPS data separately to decompose them into an ability component and an item-position component. The results of relating the components to executive functions showed that the updating and shifting processes mainly contributed to the item-position component whereas the inhibition process was mainly associated with the ability component of each fluid intelligence test. These findings suggest that improvements in the efficiency of updating and shifting processes are likely to occur during the course of completing intelligence measures and inhibition is important for intelligence in general.

Executive functions in alcohol-dependence: A theoretically grounded and integrative exploration

BACKGROUND

Alcohol-dependence is related to large-scale cognitive impairments, particularly for executive functions (EF). These deficits persist even after long-term abstinence and have a major impact on patients' everyday life and relapse risk. Earlier studies, based on multi-determined tasks, mostly focused on inhibition and did not offer a theoretically-grounded and exhaustive view of the differential deficit across EF. The present paper proposes a model-based exploration of EF in alcohol-dependent individuals (ALC), to precisely compare the specific deficit related to each executive subcomponent.

METHODS

Forty-seven recently detoxified ALC were compared to 47 matched healthy participants on a nine-tasks validated neuropsychological battery, simultaneously exploring and comparing the three main executive subcomponents (shifting, updating, and inhibition). Psychopathological comorbidities were also controlled for.

RESULTS

Reaction time indexes revealed a global slowing down among ALC, whatever the EF explored. Accuracy indexes revealed a moderate deficit for inhibition tasks but a massive impairment for shifting and updating ones. Complementary analyses indicated that the executive deficits observed were centrally related to alcohol-dependence, while comorbid depressive symptoms appeared to intensify the deficits observed.

CONCLUSIONS

By offering a direct comparison between the three major EF, these results showed that alcohol-related executive deficits extend beyond the classically described inhibition impairment. This impairment encompasses each EF subcomponent, as ALC actually presented stronger deficits for updating and shifting abilities. This first observation of a multifaceted EF deficit stresses the need for an individualized evaluation and rehabilitation of EF during and/or after the detoxification process.

Profiles of Executive Function Across Children with Distinct Brain Disorders: Traumatic Brain Injury, Stroke, and Brain Tumor

OBJECTIVES

This study examined whether children with distinct brain disorders show different profiles of strengths and weaknesses in executive functions, and differ from children without brain disorder.

METHODS

Participants were children with traumatic brain injury (N=82; 8-13 years of age), arterial ischemic stroke (N=36; 6-16 years of age), and brain tumor (N=74; 9-18 years of age), each with a corresponding matched comparison group consisting of children with orthopedic injury (N=61), asthma (N=15), and classmates without medical illness (N=68), respectively. Shifting, inhibition, and working memory were assessed, respectively, using three Test of Everyday Attention: Children's Version (TEA-Ch) subtests: Creature Counting, Walk-Don't-Walk, and Code Transmission. Comparison groups did not differ in TEA-Ch performance and were merged into a single control group. Profile analysis was used to examine group differences in TEA-Ch subtest scaled scores after controlling for maternal education and age.

RESULTS

As a whole, children with brain disorder performed more poorly than controls on measures of executive function. Relative to controls, the three brain injury groups showed significantly different profiles of executive functions. Importantly, post hoc tests revealed that performance on TEA-Ch subtests differed among the brain disorder groups.

CONCLUSIONS

Results suggest that different childhood brain disorders result in distinct patterns of executive function deficits that differ from children without brain disorder. Implications for clinical practice and future research are discussed. (JINS, 2017, 23, 529-538).

Cognitive advantages of immersion education after 1year: Effects of amount of exposure

Previous studies with bilingual children have shown that the nature of their second-language instruction has an effect on the development of their cognitive abilities. The aim of this study was to determine whether children who acquire a second language in two different immersion programs for a period of 1year show advantages in executive functions and to examine how the amount of daily exposure affects executive functions. A group of Serbian-speaking second-grade children exposed to the second language for about 5h each day (high exposure group, HEG) and a low-exposure group (LEG) exposed to the second language for about 1.5h each day were compared with an age-matched control group (CG) of monolingual peers on working memory, inhibition, and shifting. Significant group differences were found for working memory, with the HEG performing better than the CG and LEG even after controlling for individual differences in terms of age and intelligence. The three groups did not differ in terms of inhibition and overall shifting abilities, although the control group had a marginally significant advantage on one of the two shifting tasks. Our findings extend previous research by demonstrating that the amount of daily exposure is a significant factor affecting executive functions in early immersion programs for second-language acquisition. In addition, they show that early intensive second-language acquisition can be advantageous for performance on tasks that require a higher level of executive control.

The role of working memory capacity and interference resolution mechanisms in task switching

Theories of task switching have emphasized a number of control mechanisms that may support the ability to flexibly switch between tasks. The present study examined the extent to which individual differences in working memory (WM) capacity and two measures of interference resolution, response-distractor inhibition and resistance to proactive interference (PI), account for variability in task switching, including global costs, local costs, and N-2 repetition costs. A total of 102 young and 60 older adults were tested on a battery of tasks. Composite scores were created for WM capacity, response-distractor inhibition, and resistance to PI; shifting was indexed by rate residual scores, which combine response time and accuracy and account for individual differences in processing speed. Composite scores served as predictors of task switching. WM was significantly related to global switch costs. While resistance to PI and WM explained some variance in local costs, these effects did not reach significance. In contrast, none of the control measures explained variance in N-2 repetition costs. Furthermore, age effects were only evident for N-2 repetition costs, with older adults demonstrating larger costs than young adults. Results are discussed within the context of theoretical models of task switching.

Executive function deficits associated with current and past major depressive symptoms

BACKGROUND

Although there has been extensive research showing that depression is associated with executive function (EF) deficits, the nature of these deficits is not clearly delineated. Specifically, previous reviews on this topic have yielded different conclusions about the particular domains of EF that are disrupted in depressed individuals. Further, research on whether these deficits persist after depressed mood has remitted is less prevalent and not consistent.

METHODS

In two independent samples of college students, we examined associations between clinical ratings of current and past symptoms of a Major Depressive Episode (MDE) and difficulties in two domains of EF: inhibition and shifting. In Study 1 (n=162), EF was measured using behavioral tasks shown to index these two domains. In Study 2 (n=95), EF was measured using a self-report questionnaire believed to capture EF difficulties experienced in daily life.

RESULTS

In both studies, past MDE symptoms were associated with worse shifting. In contrast, current MDE symptoms were associated with worse inhibition, though only on the behavioral measure (in Study 1).

LIMITATIONS

Both studies used college samples and retrospective assessments of past symptoms. Further, only two domains of EF were examined, and the EF measures employed in each study have their own unique methodological limitations.

CONCLUSIONS

Findings suggest that inhibition deficits vary as a function of current symptoms and thus may be a by-product of distress rather than a causal contributor. In contrast, shifting deficits associated with depression appear to be more enduring, suggesting that they could contribute to risk for depression.

Theory of mind in middle childhood and early adolescence: Different from before?

Studies with preschool children have shown that language and executive function are important for theory of mind, but few studies have examined these associations in older children and in an integrative theory-guided manner. The theory of constructive operators was used as a framework to test a model of relations among mental attentional capacity, attentional inhibition, language, executive processes (shifting and updating), and higher order theory of mind in two groups of school-aged children: one in middle childhood (n=226; mean age=8.08years) and the other in early adolescence (n=216; mean age=12.09years). Results revealed a complex model of interrelations between cognitive resources and language in middle childhood that directly and indirectly predicted theory of mind. The model in early adolescence was less complex, however, and highlighted the importance of semantic language and shifting for theory of mind. Our findings suggest not only that contributors to theory of mind change over time but also that they may depend on the maturity level of the theory of mind system being examined.

Mindfulness meditation practice and executive functioning: Breaking down the benefit

This paper focuses on evidence for mindfulness meditation-related benefits to executive functioning, processes important for much of human volitional behaviour. Miyake et al. (2000) have shown that executive functions can be fractionated into three distinct domains including inhibition, working memory updating, and mental set shifting. Considering these separable domains, it is important to determine whether the effects of mindfulness can generalize to all three sub-functions or are specific to certain domains. To address this, the current review applied Miyake et al.'s (2000) fractionated model of executive functioning to the mindfulness literature. Empirical studies assessing the benefits of mindfulness to measures tapping the inhibition, updating, and shifting components of executive functioning were examined. Results suggest a relatively specific as opposed to general benefit resulting from mindfulness, with consistent inhibitory improvement, but more variable advantages to the updating and shifting domains. Recommendations surrounding application of mindfulness practice and future research are discussed.

Tracking Color Shift in Ballpoint Pen Ink Using Photoshop Assisted Spectroscopy: A Nondestructive Technique Developed to Rehouse a Nobel Laureate's Manuscript

Many historically and culturally significant documents from the mid-to-late twentieth century were written in ballpoint pen inks, which contain light-sensitive dyes that present problems for collection custodians and paper conservators. The conservation staff at the National Library of Medicine (NLM), National Institutes of Health, conducted a multiphase project on the chemistry and aging of ballpoint pen ink that culminated in the development of a new method to detect aging of ballpoint pen ink while examining a variety of storage environments. NLM staff determined that ballpoint pen ink color shift can be detected noninvasively using image editing software. Instructions are provided on how to detect color shift in digitized materials using a technique developed specifically for this project-Photoshop Assisted Spectroscopy.¹ The study results offer collection custodians storage options for historic documents containing ballpoint pen ink.

Neural networks supporting switching, hypothesis testing, and rule application

We identified dynamic changes in recruitment of neural connectivity networks across three phases of a flexible rule learning and set-shifting task similar to the Wisconsin Card Sort Task: switching, rule learning via hypothesis testing, and rule application. During fMRI scanning, subjects viewed pairs of stimuli that differed across four dimensions (letter, color, size, screen location), chose one stimulus, and received feedback. Subjects were informed that the correct choice was determined by a simple unidimensional rule, for example "choose the blue letter". Once each rule had been learned and correctly applied for 4-7 trials, subjects were cued via either negative feedback or visual cues to switch to learning a new rule. Task performance was divided into three phases: Switching (first trial after receiving the switch cue), hypothesis testing (subsequent trials through the last error trial), and rule application (correct responding after the rule was learned). We used both univariate analysis to characterize activity occurring within specific regions of the brain, and a multivariate method, constrained principal component analysis for fMRI (fMRI-CPCA), to investigate how distributed regions coordinate to subserve different processes. As hypothesized, switching was subserved by a limbic network including the ventral striatum, thalamus, and parahippocampal gyrus, in conjunction with cortical salience network regions including the anterior cingulate and frontoinsular cortex. Activity in the ventral striatum was associated with switching regardless of how switching was cued; visually cued shifts were associated with additional visual cortical activity. After switching, as subjects moved into the hypothesis testing phase, a broad fronto-parietal-striatal network (associated with the cognitive control, dorsal attention, and salience networks) increased in activity. This network was sensitive to rule learning speed, with greater extended activity for the slowest learning speed late in the time course of learning. As subjects shifted from hypothesis testing to rule application, activity in this network decreased and activity in the somatomotor and default mode networks increased.

Executive function and suicidality: A systematic qualitative review

Deficits in executive function (EF) have been proposed as a possible explanation for the "cognitive rigidity" often observed in suicidal individuals. This article provides a systematic review of the existing literature testing the relations between EF and suicidality, across various diagnostic and demographic populations, using the influential multidimensional model of EF proposed by Miyake and colleagues (2000) as an organizing framework. Forty-three journal articles on this topic published before January of 2014 were reviewed. Collectively, results from these studies provide tentative support for an association between EF deficits and suicidality. However, there is some evidence that this association is moderated by other factors (e.g., suicide attempt lethality). Importantly, this relationship may vary across diagnostic groups. Specifically, more studies that used depressive disorder samples reported some positive findings (75%), followed by mixed diagnostic samples (54%). In contrast, fewer positive findings have emerged from studies with bipolar or psychotic disorder samples (29% and 33% respectively), and some even found that suicidality is associated with better EF in individuals with psychotic disorders. Firm conclusions about relationships between specific dimensions of EF and/or aspects of suicidality are difficult to draw this time. Limitations of the existing literature and corresponding directions for future research are discussed.

Executive functioning in children with developmental dyslexia

The term "executive function" has been used to describe several higher-order cognitive processes. This study examined the processing speed, shifting, planning, and verbal fluency of a sample of 50 Portuguese children with developmental dyslexia (DD) and 50 typically developing children (TDC; chronological-age-matched controls) between 8 and 12 years of age to evaluate the children's executive functioning. Compared to TDC, children with DD revealed significant processing speed, shifting, and verbal fluency deficits. After controlling for differences in the general intellectual ability, significant group differences remained for shifting, verbal fluency and marginally for processing speed. No significant differences in planning ability were observed between the groups. No significant interaction of group, gender, and age was found for any of the executive functions measures studied. Word productivity in both semantic and phonemic verbal fluency tasks decreased significantly over the 60 seconds for both groups. Shifting was the only significant predictor of DD in the binary logistic regression analysis and yielded the highest area under the curve value (receiver operating characteristics curve analysis). Therefore, although these findings highlight the presence of specific executive functions deficits in children with DD, they should not be interpreted as indicative of the presence or absence of this learning disorder.

No clear evidence for a positive association between the interpersonal-affective aspects of psychopathy and executive functioning

Common psychopathy rating instruments distinguish between an interpersonal-affective and an antisocial dimension. The suggestion that the interpersonal-affective dimension, often considered to be the core feature of psychopathy, is positively associated with executive functioning is occasionally made in the literature, without reporting objective empirical data. The primary aim of the present paper was to search for empirical studies reporting relevant data, focussing on four aspects of 'cold' executive functioning: inhibition, attentional shifting, working memory, and planning. Eleven published articles were identified, reporting data of 721 individuals from incarcerated and non-incarcerated, male and female, and adult and non-adult samples. Using a heterogeneous set of tests and dependent measures across studies, the inhibition and attentional shifting components were assessed in eight and five studies, respectively; the working memory and planning components each in two studies. A small majority of the studies found positive associations with the different executive functions, although the associations were mostly non-significant. Given the scarcity of studies and the use of heterogeneous populations, tests and statistical analyses, no robust conclusions can be drawn at this stage. Therefore, caution is needed when claiming a positive association between the interpersonal-affective features of psychopathy and executive functioning. Clearly more research is needed to further validate and specify the suggested association.