Individual Differences In Executive Function Research Articles

Executive functioning and dietary intake: Neurocognitive correlates of fruit, vegetable, and saturated fat intake in adults with obesity

Obesity is a significant public health issue, and is associated with poor diet. Evidence suggests that eating behavior is related to individual differences in executive functioning. Poor executive functioning is associated with poorer diet (few fruits and vegetables and high saturated fat) in normal weight samples; however, the relationship between these specific dietary behaviors and executive functioning have not been investigated in adults with obesity. The current study examined the association between executive functioning and intake of saturated fat, fruits, and vegetables in an overweight/obese sample using behavioral measures of executive function and dietary recall. One-hundred-ninety overweight and obese adults completed neuropsychological assessments measuring intelligence, planning ability, and inhibitory control followed by three dietary recall assessments within a month prior to beginning a behavioral weight loss treatment program. Inhibitory control and two of the three indices of planning each independently significantly predicted fruit and vegetable consumption such that those with better inhibition and planning ability consumed more fruits and vegetables. No relationship was found between executive functioning and saturated fat intake. Results increase understanding of how executive functioning influences eating behavior in overweight and obese adults, and suggest the importance of including executive functioning training components in dietary interventions for those with obesity. Further research is needed to determine causality as diet and executive functioning may bidirectionally influence each other.

Chronnectomic patterns and neural flexibility underlie executive function

Despite extensive research into executive function (EF), the precise relationship between brain dynamics and flexible cognition remains unknown. Using a large, publicly available dataset (189 participants), we find that functional connections measured throughout 56min of resting state fMRI data comprise five distinct connectivity states. Elevated EF performance as measured outside of the scanner was associated with greater episodes of more frequently occurring connectivity states, and fewer episodes of less frequently occurring connectivity states. Frequently occurring states displayed metastable properties, where cognitive flexibility may be facilitated by attenuated correlations and greater functional connection variability. Less frequently occurring states displayed properties consistent with low arousal and low vigilance. These findings suggest that elevated EF performance may be associated with the propensity to occupy more frequently occurring brain configurations that enable cognitive flexibility, while avoiding less frequently occurring brain configurations related to low arousal/vigilance states. The current findings offer a novel framework for identifying neural processes related to individual differences in executive function.

Temporal Information Processing and its Relation to Executive Functions in Elderly Individuals.

Normal aging triggers deterioration in cognitive functions. Evidence has shown that these age-related changes concern also executive functions (EF) as well as temporal information processing (TIP) in a millisecond range. A considerable amount of literature data has indicated that each of these two functions sets a frame for our mental activity and may be considered in terms of embodied cognition due to advanced age. The present study addresses the question whether in elderly subjects the efficiency of TIP is related to individual differences in EF. The study involved 53 normal healthy participants aged from 65 to 78. In these subjects TIP was assessed by sequencing abilities measured with temporal-order threshold (TOT). It is defined as the minimum time gap separating two auditory stimuli presented in rapid succession which is necessary for a subject to report correctly their temporal order, thus the relation ‘before-after.’ The EF were assessed with regard to the efficiency of the executive planning measured with the Tower of London-Drexel University (TOLDX) which has become a well-known EF task. Using Spearman’s rank correlations we observed two main results. Firstly, the indices of the TOLDX indicated a coherent construct reflecting the effectiveness of executive planning in the elderly. Initiation time seemed dissociated from these coherent indices, which suggested a specific strategy of mental planning in the elderly based on on-line planning rather than on preplanning. Secondly, TOT was significantly correlated with the indices of TOLDX. Although some of these correlations were modified by subject’s age, the correlation between TOT and the main index of TOLDX (‘Total Move Score’) was rather age resistant. These results suggest that normal aging may be characterized by an overlapping of deteriorated TIP and deteriorated EF.

Assessing Executive Functions in Preschoolers Using Shape School Task.

Over the last two decades, there has been a growing interest in the study of the development of executive functions (EF) in preschool children due to their relationship with different cognitive, psychological, social and academic domains. Early detection of individual differences in executive functioning can have major implications for basic and applied research. Consequently, there is a key need for assessment tools adapted to preschool skills: Shape School has been shown to be a suitable task for this purpose. Our study uses Shape School as the main task to analyze development of inhibition, task-switching and working memory in a sample of 304 preschoolers (age range 3.25–6.50 years). Additionally, we include cognitive tasks for the evaluation of verbal variables (vocabulary, word reasoning and short-term memory) and performance variables (picture completion and symbol search), so as to analyze their relationship with EFs. Our results show age-associated improvements in EFs and the cognitive variables assessed. Furthermore, correlation analyses reveal positive relationships between EFs and the other cognitive variables. More specifically, using structural equation modeling and including age direct and indirect effects, our results suggest that EFs explain to a greater extent performance on verbal and performance tasks. These findings provide further information to support research that considers preschool age to be a crucial period for the development of EFs and their relationship with other cognitive processes.

Individual differences in categorical perception of speech: Cue weighting and executive function

This study examined individual differences in categorical perception and the use of multiple acoustic cues in the perception of the stop voicing contrast. Goals were to investigate whether gradiency of speech perception was related to listeners’ differential sensitivity to acoustic cues and to individual differences in executive function. The experiment included two speech perception tasks (visual analogue scaling [VAS] and anticipatory eye movement [AEM]) administered to 30 English-speaking adults in two separate experimental sessions. Stimuli were a /ta/ to /da/ continuum that systematically varied VOT and f0. Findings were that some listeners had a more gradient pattern of responses on the VAS task; the listeners who had a gradient response pattern on the VAS task also showed more sensitivity to f0 on the AEM task. The patterns were consistent across individuals tested on two separate occasions. These results suggest that variability in how categorically listeners perceive speech sounds is consistent and systematic within individuals.

Strong genetic overlap between executive functions and intelligence.

Executive functions (EFs) are cognitive processes that control, monitor, and coordinate more basic cognitive processes. EFs play instrumental roles in models of complex reasoning, learning, and decision making, and individual differences in EFs have been consistently linked with individual differences in intelligence. By middle childhood, genetic factors account for a moderate proportion of the variance in intelligence, and these effects increase in magnitude through adolescence. Genetic influences on EFs are very high, even in middle childhood, but the extent to which these genetic influences overlap with those on intelligence is unclear. We examined genetic and environmental overlap between EFs and intelligence in a racially and socioeconomically diverse sample of 811 twins ages 7 to 15 years (M = 10.91, SD = 1.74) from the Texas Twin Project. A general EF factor representing variance common to inhibition, switching, working memory, and updating domains accounted for substantial proportions of variance in intelligence, primarily via a genetic pathway. General EF continued to have a strong, genetically mediated association with intelligence even after controlling for processing speed. Residual variation in general intelligence was influenced only by shared and nonshared environmental factors, and there remained no genetic variance in general intelligence that was unique of EF. Genetic variance independent of EF did remain, however, in a more specific perceptual reasoning ability. These results provide evidence that genetic influences on general intelligence are highly overlapping with those on EF. (PsycINFO Database Record

The “EF” in deficiency: Examining the linkages between executive function and the utilization deficiency observed in preschoolers

We investigated the contribution of preschoolers’ executive function (EF) skills to the effectiveness of their spontaneous strategy production when learning. Performance on computerized tasks of inhibition, attention shifting, and working memory was examined in relation to the effectiveness of 112 3- to 5-year-olds’ spontaneous strategy production on a spatial memory task. Participants were asked to remember the locations of four toys representing one of two categories (animals or chairs) placed in a wooden box. Most participants spontaneously implemented a clustering strategy by removing and/or replacing the toys according to category membership. However, less than half of these strategic participants showed concomitant memory benefits (recall of toy locations). The remainder showed a utilization deficiency. After controlling for age and IQ, participants who performed better on EF tasks were more likely to benefit from having used the clustering strategy. These findings indicate that utilization deficiencies among preschoolers may be partially accounted for by individual differences in EF.

Functional connectivity at rest is sensitive to individual differences in executive function: A network analysis.

Graph theory provides a means to understand the nature of network characteristics and connectivity between specific brain regions. Here it was used to investigate whether the network characteristics of the brain at rest are associated with three dimensions thought to underlie individual differences in executive function (EF)-common EF, shifting-specific EF, and updating-specific EF (Miyake and Friedman [2012]). To do so, both an a priori analysis focused mainly on select frontoparietal regions previously linked to individual differences in EF as well as a whole-brain analysis were performed. The findings indicated that individual differences in each of the three dimensions of EF were associated with specific patterns of resting-state connectivity both in a priori and other brain regions. More specifically, higher common EF was associated with greater integrative (i.e., more hublike) connectivity of cuneus and supplementary motor area but less integrative function of lateral frontal nodes and left temporal lobe nodes. Higher shifting-specific EF was associated with more hublike motor-related nodes and cingulo-opercular nodes. Higher updating-specific EF was associated with less hublike lateral and medial frontoparietal nodes. In general, these results suggested that higher ability in each of these three dimensions of EF was not solely characterized by the connectivity characteristics of frontoparietal regions. The pattern was complicated in that higher EF was associated with the connectivity profile of nodes outside of the traditional frontoparietal network, as well as with less hublike or centrality characteristics of some nodes within the frontoparietal network. Hum Brain Mapp 37:2959-2975, 2016. © 2016 Wiley Periodicals, Inc.

Research on individual differences in executive functions

Executive functions (EFs), such as response inhibition, interference control, and set shifting, are general-purpose control mechanisms that enable individuals to regulate their thoughts and behaviors. Because bilingual individuals use EF-like processes during language control, researchers have become interested in the hypothesis that this use might train EFs, resulting in better performance on non-linguistic EF tasks. Although this bilingual advantage hypothesis seems straightforward to test, it involves a number of important decisions in terms of how to assess bilingualism and EFs. In this article, I focus on the complexity of measuring EFs, drawing on individual differences research (conducted with participants not selected for bilingualism). Specifically, I discuss issues related to (1) the measurement of EFs (particularly the effects of task impurity and unreliability) and (2) the multicomponent nature of EFs. Within each of these topics, I elaborate on consequences for research on bilingual advantages and provide some recommendations.

Executive function predicts the development of play skills for verbal preschoolers with autism spectrum disorders.

Executive function and play skills develop in early childhood and are linked to cognitive and language ability. The present study examined these abilities longitudinally in two groups with autism spectrum disorder-a group with higher initial language (n = 30) and a group with lower initial language ability (n = 36). Among the lower language group, concurrent nonverbal cognitive ability contributed most to individual differences in executive function and play skills. For the higher language group, executive function during preschool significantly predicted play ability at age 6 over and above intelligence, but early play did not predict later executive function. These results suggested that factors related to the development of play and executive function differ for subgroups of children with different language abilities and that early executive function skills may be critical in order for verbal children with autism to develop play. Autism Res 2016, 9: 1274-1284. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

Cognitive flexibility modulates maturation and music-training-related changes in neural sound discrimination.

Previous research has demonstrated that musicians show superior neural sound discrimination when compared to non-musicians, and that these changes emerge with accumulation of training. Our aim was to investigate whether individual differences in executive functions predict training-related changes in neural sound discrimination. We measured event-related potentials induced by sound changes coupled with tests for executive functions in musically trained and non-trained children aged 9-11years and 13-15years. High performance in a set-shifting task, indexing cognitive flexibility, was linked to enhanced maturation of neural sound discrimination in both musically trained and non-trained children. Specifically, well-performing musically trained children already showed large mismatch negativity (MMN) responses at a young age as well as at an older age, indicating accurate sound discrimination. In contrast, the musically trained low-performing children still showed an increase in MMN amplitude with age, suggesting that they were behind their high-performing peers in the development of sound discrimination. In the non-trained group, in turn, only the high-performing children showed evidence of an age-related increase in MMN amplitude, and the low-performing children showed a small MMN with no age-related change. These latter results suggest an advantage in MMN development also for high-performing non-trained individuals. For the P3a amplitude, there was an age-related increase only in the children who performed well in the set-shifting task, irrespective of music training, indicating enhanced attention-related processes in these children. Thus, the current study provides the first evidence that, in children, cognitive flexibility may influence age-related and training-related plasticity of neural sound discrimination.

Stability and change in executive function abilities from late adolescence to early adulthood: A longitudinal twin study.

Executive functions (EFs)-the higher level cognitive abilities that enable us to control our own thoughts and actions-continue to develop into early adulthood, yet no longitudinal study has examined their stability during the important life transition from late adolescence to young adulthood. In this twin study (total N = 840 individuals from 424 families), we examined the stability of individual differences in 3 EF components across a 6-year period, from approximately age 17 years (Wave 1) to 23 years (Wave 2). Specifically, we address the following questions: (a) How stable are individual differences in multiple EFs across this time period? and (b) What (genetic and/or environmental) influences affect stability and change in EFs? Results indicated that individual differences in EFs are quite stable across this 6-year period (phenotypic latent variable correlations ranged from 0.86 to 1.0). However, there was evidence for change, particularly in the factor common to multiple EFs (Common EF). Multivariate twin models suggested that stability was due almost entirely to high genetic correlations across time; there was no new genetic variance at Wave 2. Change in Common EF was due to small but significant nonshared environmental influences at Wave 2 (15%). The results suggest that individual differences in EFs are quite heritable and stable by late adolescence, yet are still sensitive to environmental influences.

Developmental Delays in Executive Function from 3 to 5 Years of Age Predict Kindergarten Academic Readiness

Substantial evidence has established that individual differences in executive function (EF) in early childhood are uniquely predictive of children’s academic readiness at school entry. The current study tested whether growth trajectories of EF across the early childhood period could be used to identify a subset of children who were at pronounced risk for academic impairment in kindergarten. Using data that were collected at the age 3, 4, and 5 home assessments in the Family Life Project (N = 1,120), growth mixture models were used to identify 9% of children who exhibited impaired EF performance (i.e., persistently low levels of EF that did not show expected improvements across time). Compared to children who exhibited typical trajectories of EF, the delayed group exhibited substantial impairments in multiple indicators of academic readiness in kindergarten (Cohen’s ds = 0.9–2.7; odds ratios = 9.8–23.8). Although reduced in magnitude following control for a range of socioeconomic and cognitive (general intelligence screener, receptive vocabulary) covariates, moderate-sized group differences remained (Cohen’s ds = 0.2–2.4; odds ratios = 3.9–5.4). Results are discussed with respect to the use of repeated measures of EF as a method of early identification, as well as the resulting translational implications of doing so.

Taking your own path: Individual differences in executive function and language processing skills in child learners

Children as old as 5 or 6years display selective difficulties in revising initial interpretive commitments, as indicated by both online and offline measures of sentence comprehension. It is likely, however, that individual children differ in how well they can recover from misinterpretations and in the age at which they become adult-like in these abilities. To better understand the cognitive functions that support sentence processing and revision, the current work investigated how individual differences in children’s ability to interpret temporarily ambiguous sentences relate to individual differences in other linguistic and domain-general cognitive abilities. Children were tested over 2days on a battery of executive function, working memory, and language comprehension tasks. Performance on these tasks was then used to predict online and offline measures of children’s ability to revise initial misinterpretations of temporarily ambiguous sentences. We found two measures of children’s cognitive flexibility to be related to their ambiguity resolution abilities. These results provide converging evidence for the hypothesis that the ability to revise initial interpretive commitments is supported by domain-general executive function abilities, which are highly variable and not fully developed in children.

The role of age and executive function in auditory category learning

Auditory categorization is a natural and adaptive process that allows for the organization of high-dimensional, continuous acoustic information into discrete representations. Studies in the visual domain have identified a rule-based learning system that learns and reasons via a hypothesis-testing process that requires working memory and executive attention. The rule-based learning system in vision shows a protracted development, reflecting the influence of maturing prefrontal function on visual categorization. The aim of the current study was twofold: (a) to examine the developmental trajectory of rule-based auditory category learning from childhood through adolescence and into early adulthood and (b) to examine the extent to which individual differences in rule-based category learning relate to individual differences in executive function. A sample of 60 participants with normal hearing—20 children (age range=7–12years), 21 adolescents (age range=13–19years), and 19 young adults (age range=20–23years)—learned to categorize novel dynamic “ripple” sounds using trial-by-trial feedback. The spectrotemporally modulated ripple sounds are considered the auditory equivalent of the well-studied “Gabor” patches in the visual domain. Results reveal that auditory categorization accuracy improved with age, with young adults outperforming children and adolescents. Computational modeling analyses indicated that the use of the task-optimal strategy (i.e., a conjunctive rule-based learning strategy) improved with age. Notably, individual differences in executive flexibility significantly predicted auditory category learning success. The current findings demonstrate a protracted development of rule-based auditory categorization. The results further suggest that executive flexibility coupled with perceptual processes play important roles in successful rule-based auditory category learning.

Latent profiles of executive functioning in healthy young adults: evidence of individual differences in hemispheric asymmetry.

Two competing theoretical models of individual differences in executive functioning (EF) were examined: the Prefrontal Convexity Model and the Hemispheric Asymmetry Model. Neurologically healthy individuals (N=315; mean age 20.8) completed a modified switching task (MST) and the Attention Network Test (ANT) in a single testing session. Data analysis was conducted in two phases. In the first phase (model identification), latent profile analysis was applied to MST variables measuring the abilities to form, switch, and maintain mental sets under conditions designed to tax left or right hemisphere resources. In the second phase (model validation), participant clusters obtained from the first phase were compared on the ANT. The Model Identification phase yielded a 3-profile solution consistent with the Hemispheric Asymmetry Model. Profile 1 (N=203) was characterized by average EF performances. Profile 2 (N=43) revealed a set maintenance weakness under non-verbal conditions. Profile 3 (N=38) demonstrated weaknesses in cognitive flexibility combined with poor executive performances under verbal conditions. The Model Validation phase confirmed group differences. Profile 1 demonstrated average EF performances. Profile 2 demonstrated distractibility and decreased alertness, consistent with a right hemisphere weakness. Profile 3 demonstrated cognitive rigidity in the absence of external cues, consistent with a left hemisphere weakness. Individual differences in EF appear to follow a Hemispheric Asymmetry Model of EF among neurologically healthy adults. Investigating the relationship between hemispherically mediated executive functions and other individual difference factors known to confer health risk or resilience could inform numerous disciplines within the field of psychology.

Cognitive processes in the Breakfast Task: Planning and monitoring.

The Breakfast Task (Craik & Bialystok, 2006) is a computerized task that simulates the planning and monitoring requirements involved in cooking breakfast, an everyday activity important for functional independence. In Experiment 1, 28 adults performed the Breakfast Task, and outcome measures were examined with principal component analysis to elucidate the structure of cognitive processes underlying performance. Analyses revealed a 2-component structure which putatively captured global planning and local monitoring abilities. In Experiment 2, the structure of Breakfast Task performance was cross-validated on a new sample of 59 healthy older adults who also performed tests assessing working memory, processing speed, inhibition, reasoning and prospective memory. Factor analyses showed that the global planning component from the Breakfast Task was significantly correlated with individual differences in executive functions but the local monitoring component was independent of such functions. The Breakfast Task provides a fast, enjoyable, and lifelike assessment of complex everyday planning and monitoring, and their underlying processes such as working memory and executive functions.

Individual Differences in Executive Functioning and Their Relationship to Emotional Processes and Responses

The executive functions (including response inhibition, memory updating, and task switching) appear to form the core of higher-order cognitive processes in humans. Relatively little research has been devoted to the role of the executive functions in emotional and motivational processes. The current article surveys evidence on the contributions of individual differences in executive functioning to emotion and emotion regulation in adults. The findings reveal that cognitive ability helps to shape human emotional life and raise new questions about how and why this is so.

The role of age and executive function in auditory category learning

Auditory categorization is a natural and adaptive process that allows for the organization of high-dimensional, continuous acoustic information into discrete representations. The aim of this study is two-fold: (a) to examine the developmental trajectory of rule-based auditory category learning from childhood through early adulthood, and (b) to examine the extent to which individual differences in rule-based category learning relates to individual differences in executive function. Sixty participants with normal-hearing, 20 children (age range, 7–12), 20 adolescents (age range, 13–19), and 20 young adults (age range, 20–23), learned to categorize novel spectrotemporally modulated sounds using trial-by-trial feedback. The experimental design included six blocks of 100 stimuli for a total of 600 trials. Results revealed that auditory categorization accuracy improved with age, with young adults outperforming children and adolescents. Computational modeling analyses indicated that the use of the task-optimal s...

Reflection and Executive Function: Foundations for Learning and Healthy Development

Executive function (EF) refers to the neurocognitive processes involved in the deliberate, goal-directed modulation of thought, action, and emotion. Individual differences in EF measured in childhood predict key developmental outcomes, and interventions designed to foster the healthy development of EF have the potential to help children at risk for a wide range of difficulties. This article briefly describes a theoretical model of EF and its development, the Iterative Reprocessing model that spans levels of analysis and characterizes self-regulation as the product of a dynamic interaction between top-down (reflective) and bottom-up (reactive) influences.