From movement to thought: the development of executive function

Intraoperative mapping and preservation of executive functions in awake craniotomy: a systematic review

Awake craniotomy (AC) allows intraoperative brain mapping (ioBM) for maximum lesion resection while monitoring and preserving neurological function. Conventionally, language, visuospatial assessment, and motor functions are mapped, while the assessment of executive functions (EF) is uncommon. Impaired EF may lead to occupational, personal, and social limitations, thus, a compromised quality of life. A comprehensive literature search was conducted through Scopus, Medline, and Cochrane Library using a pre-defined search strategy. Articles were selected after duplicate removal, initial screening, and full-text assessment. The demographic details, ioBM techniques, intraoperative tasks, and their assessments, the extent of resection (EOR), post-op EF and neurocognitive status, and feasibility and potential adverse effects of the procedure were reviewed. The correlations of tumor locations with intraoperative EF deficits were also assessed. A total of 13 studies with intraoperative EF assessment of 351 patients were reviewed. Awake-asleep-awake protocol was most commonly used. Most studies performed ioBM using bipolar stimulation, with a frequency of 60 Hz, pulse durations ranging 1-2 ms, and intensity ranging 2-6 mA. Cognitive function was monitored with the Stroop task, spatial-2-back test, line-bisection test, trail-making-task, and digit-span tests. All studies reported similar or better EOR in patients with ioBM for EF. When comparing the neuropsychological outcomes of patients with ioBM of EF to those without it, all studies reported significantly better EF preservation in ioBM groups. Most authors reported EF mapping as a feasible tool to obtain satisfactory outcomes. Adverse effects included intraoperative seizures which were easily controlled. AC with ioBM of EF is a safe, effective, and feasible technique that allows satisfactory EOR and improved neurocognitive outcomes with minimal adverse effects.

Phenotypic and Genetic Associations Between Preschool Fine Motor Skills and Later Neurodevelopment, Psychopathology, and Educational Achievement

BACKGROUND

Fine motor skills are heritable and comprise important milestones in development, and some evidence suggests that impairments in fine motor skills are associated with neurodevelopmental conditions, psychiatric disorders, and poor educational outcomes.

METHODS

In a preregistered study of 9625 preschool children from TEDS (Twins Early Development Study), fine motor assessments (drawing, block building, folding, and questionnaires) were conducted at 2, 3, and 4 years of age. A cross-age fine motor score was derived using principal component analysis. Multivariate regression analysis was used to examine the relationships between the fine motor score and neurodevelopmental traits, psychopathology, and educational outcomes at 3 later ages (7-8, 12, and 16 years) and cross-age psychopathology composite scores. Polygenic scores (PGSs) were created for attention-deficit/hyperactivity disorder (ADHD), autism, schizophrenia, anxiety, major depressive disorder, obsessive-compulsive disorder, and years of education. We ran single-PGS models and a multi-PGS model.

RESULTS

Fine motor skills were negatively associated with neurodevelopmental traits and psychopathology across childhood and adolescence and positively associated with educational achievement in adolescence (β = 0.25, p < .001). Superior fine motor skills were associated with a higher years-of-education PGS (β = 0.07, p < .001), a lower ADHD PGS (β = -0.04, p = .011), and a higher anxiety PGS (β = 0.03, p = .040). Similarly, the multi-PGS model retained the PGSs for years of education (β = 0.07), ADHD (β = -0.03), and anxiety (β = 0.01). A non-preregistered analysis in an independent preschool sample replicated the ADHD PGS association, but not the years of education or anxiety PGS associations.

CONCLUSIONS

Fine motor skills are linked genetically and phenotypically to later neurodevelopment, psychopathology, and educational outcomes. Future work should investigate the mechanisms that underlie the role of fine motor development in later outcomes.

Associations between Gross and Fine Motor Skills, Physical Activity, Executive Function, and Academic Achievement: Longitudinal Findings from the UK Millennium Cohort Study

Accumulating evidence from behavioral studies and neuroscience suggests that motor and cognitive development are intrinsically intertwined. To explore the underlying mechanisms of this motor-cognition link, our study examined the longitudinal relationship of early motor skills and physical activity with later cognitive skills. The sample was 3188 children from the United Kingdom Millennium Cohort Study, followed at 9 months and 5, 7, and 11 years. Early motor skills were examined at 9 months. Children's daily physical activity level was measured using accelerometers at 7 years and a questionnaire was conducted at 11 years. Cognitive skills, including executive function and academic achievement, were measured at age 11. The results suggest that gross motor skills were positively associated with spatial working memory, whereas fine motor skills were predictive of good English and science outcomes. Moderate-to-vigorous activity was found to be negatively associated with English performance, although self-reported activity frequency was positively linked to math. Our results highlight the significant role of both gross and fine motor skills in cognitive development. This study also elucidates the limitations of using activity intensity to assess the impact of motor activity on children's cognitive development, suggesting that attention to the effects of specific types of physical activity would better elucidate the motor/cognition link.

Biological and environmental factors may affect children's executive function through motor and sensorimotor development: Preterm birth and cerebral palsy

Disruptive biological and environmental factors may undermine the development of children's motor and sensorimotor skills. Since the development of cognitive skills, including executive function, is grounded in early motor and sensorimotor experiences, early delays or impairments in motor and sensorimotor processing often trigger dynamic developmental cascades that lead to suboptimal executive function outcomes. The purpose of this perspective paper is to link early differences in motor/sensorimotor processing to the development of executive function in children born preterm or with cerebral palsy. Uncovering such links in clinical populations would improve our understanding of developmental pathways and key motor and sensorimotor skills that are antecedent and foundational for the development of executive function. This knowledge will allow the refinement of early interventions targeting motor and sensorimotor skills with the goal of proactively improving executive function outcomes in at-risk populations.

Biological, behavioral, and social correlates of executive function in low-income preschoolers: Insights from the perspective of the networks

Behavioral, biological, and social correlates may be related to the association between executive function (EF) and physical activity (PA), when considering such variables as an integrated and non-linear system. Thus, the aim of the present study was to investigate the relationships between EF, PA and associated correlates in low-income preschoolers according to a network perspective. Thus, 142 preschoolers of both sexes, age 3-to-5-years-old (51% girls) were analyzed. Light, moderate and vigorous PA, cardiorespiratory fitness (CRF), body mass index, family income, preterm birth, presence of siblings, presence of other children at home and the child's primary caregiver were assessed. Our results showed that EF was positively associated with age (b = 0.47), child's primary caregivers (b = 0.37), moderate PA (b = 0.30) and CRF (b = 0.25). Negative associations were seen with preterm birth (b = -0.50), vigorous PA (b = -0.34), presence of other children at home (b = -0.25), and sex (b = -0.33). The network's centrality indicators highlighted preterm birth and moderate PA as the most important variables in the network. Future interventions aiming to increase low-income preschoolers' EF should focus on increasing moderate PA, with special attention to preterm children.

The assessment of executive functions to test the integrity of the nigrostriatal network: A pilot study

Background

Parkinson’s disease (PD) is a chronic neurodegenerative disorder characterized by motor and non-motor symptoms. The latter mainly include affective, sleep, and cognitive deficits. Non-demented PD patients often demonstrate impairments in several executive domains following neuropsychological evaluation. The current pilot study aims at assessing the discriminatory power of the Frontal Assessment Battery-15 (FAB15) in differentiating (i) non-demented PD patients and healthy controls and (ii) PD patients with more and less pronounced motor symptoms.

Methods

Thirty-nine non-demented early-stage PD patients in the “on” dopamine state (26 females, mean age = 64.51 years, SD = 6.47, mean disease duration = 5.49 years, SD = 2.28) and 39 healthy participants (24 females, mean age = 62.60 years, SD = 5.51) were included in the study. All participants completed the FAB15. Motor symptoms of PD patients were quantified via the Unified Parkinson’s Disease Rating Scale-Part III (UPDRS-Part III) and Hoehn and Yahr staging scale (H&amp;Y).

Results

The FAB15 score, adjusted according to normative data for sex, age, and education, proved to be sufficiently able to discriminate PD patients from healthy controls (AUC = 0.69 [95% CI 0.60–0.75], SE = 0.06, p = 0.04, optimal cutoff = 11.29). Conversely, the battery lacked sufficient discriminative capability to differentiate PD patients based on the severity of motor symptoms.

Conclusion

The FAB15 may be a valid tool for distinguishing PD patients from healthy controls. However, it might be less sensitive in identifying clinical phenotypes characterized by visuospatial impairments resulting from posteroparietal and/or temporal dysfunctions. In line with previous evidence, the battery demonstrated to be not expendable in the clinical practice for monitoring the severity of PD-related motor symptoms.

The effect of mindfulness-based intervention on neurobehavioural functioning and its association with white-matter microstructural changes in preterm young adolescents

Very preterm (VPT) young adolescents are at high risk of executive, behavioural and socio-emotional difficulties. Previous research has shown significant evidence of the benefits of mindfulness-based intervention (MBI) on these abilities. This study aims to assess the association between the effects of MBI on neurobehavioral functioning and changes in white-matter microstructure in VPT young adolescents who completed an 8-week MBI program. Neurobehavioural assessments (i.e., neuropsychological testing, parents- and self-reported questionnaires) and multi-shell diffusion MRI were performed before and after MBI in 32 VPT young adolescents. Combined diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI) measures were extracted on well-defined white matter tracts (TractSeg). A multivariate data-driven approach (partial least squares correlation) was used to explore associations between MBI-related changes on neurobehavioural measures and microstructural changes. The results showed an enhancement of global executive functioning using parent-reported questionnaire after MBI that was associated with a general pattern of increase in fractional anisotropy (FA) and decrease in axonal dispersion (ODI) in white-matter tracts involved in executive processes. Young VPT adolescents with lower gestational age at birth showed the greatest gain in white-matter microstructural changes after MBI.

Similar Cognitive Skill Impairment in Children with Upper Limb Motor Disorders Due to Arthrogryposis Multiplex Congenita and Obstetrical Brachial Plexus Palsy

Arthrogryposis multiplex congenita (AMC) and obstetrical brachial plexus palsy (OBPP) are motor disorders with similar symptoms (contractures and the disturbance of upper limb function). Both conditions present as flaccid paresis but differ from each other in the pathogenesis: AMC is a congenital condition, while OBPP results from trauma during childbirth. Despite this difference, these diseases are identical in terms of their manifestations and treatment programmes. We compared the cognitive skills of children with AMC and OBPP diagnoses with those of healthy children; we also compared the motor skills of impaired children with those of healthy ones. The patients in both groups significantly differed from the healthy children with regard to psychological parameters, such as 'visual memory capacity' and 'thinking'. Moreover, the two groups with children with AMC and OBPP significantly differed from each other in motor skill parameters, such as 'delayed motor development', 'general motor development', and the 'level of paresis'. Upper limb motor function in the OBPP children was less impaired compared to that of the AMC children. However, we did not find any significant differences in cognitive deficits between the AMC children and the OBPP children. This may indicate that motor impairment is more significant than the underlying cause for the development of cognitive impairment; however, the factors causing this phenomenon require further study (e.g., social environment, treatment, and rehabilitation programme).

Motor skills and cognitive benefits in children and adolescents: Relationship, mechanism and perspectives

OBJECTIVE

There is a strong interaction between motor skills and cognitive benefits for children and young people. The aim of this paper is to explore the relationship between motor skill types and their development and the cognitive benefits of children and adolescents. In turn, on this basis, it proposes pathways and mechanisms by which motor skills improve cognition, and provide a basis for subsequent teaching of skills that follow the laws of brain cognitive development.

METHODS

This paper summarizes the research on the relationship between different types of motor skills and their development and cognitive benefits of children and adolescents. Based on these relationships, pathways, and mechanisms for motor skills to improve cognition are tentatively proposed.

RESULTS

There is an overall pattern of "open > closed, strategy > interception, sequence > continuous" between motor skill types and the cognitive benefits of children and adolescents. Long-term motor skill learning practice is accompanied by increased cognitive benefits as skill proficiency increases. The dynamic interaction between motor skills and physical activity exposes children and adolescents to environmental stimuli and interpersonal interactions of varying complexity, promoting the development of agility, coordination and cardiorespiratory fitness, enhancing their motor experience, which in turn improves brain structure and functional activity.

CONCLUSION

Motor skills training promote cognitive efficiency in children and adolescents. Motor skill interventions that are open-ended, strategic and sequential in nature are more effective. Environmental stimuli, interpersonal interaction, agility, coordination, and cardiorespiratory fitness can be considered as skill attribute moderators of motor skills to improve cognition.

The Neglected Factor in the Relationship between Executive Functioning and Obesity: The Role of Motor Control

BACKGROUND

The association between obesity and executive functions (EFs) is highly controversial. It has been suggested that waist circumference (WC), compared to body mass index (BMI), is a better indicator of fat mass and EFs in obesity. Moreover, according to the viewpoint that the brain's functional architecture meets the need for interactive behavior, we hypothesize that the relationship between EFs and body weight might be mediated by the motor performance.

METHODS

General executive functioning (frontal assessment battery-15), additional cognitive subdomains (trail making test and digit span backward), and motor performance (finger tapping task) were assessed in a sample that included 330 volunteers (192 females, M age = 45.98 years, SD = 17.70, range = 18-86 years).

RESULTS

Hierarchical multiple regression analysis indicated that the FAB15 score and FTT negatively predicted WC but not BMI. A subsequent mediation analysis highlighted that the indirect effect of FAB15 on WC through finger tapping was statistically significant.

CONCLUSIONS

Our results suggest that WC, as compared to BMI, is a more effective measure for studying the association between EFs and body weight. Still, we found that the motor domain partially mediates the dynamics of such a relationship.

Understanding Mathematical Learning Disorder in Regard to Executive and Cerebellar Functioning: a Failure of Procedural Consolidation

A burgeoning body of literature in pediatric neuropsychological assessment suggests executive functioning is the foundation of many procedural learning skills as mediated by cerebellar processing. Given the neuropsychological necessity of intact procedural learning ability for efficient academic learning, the accurate identification of what we have termed “procedural consolidation deficit” (PCD) may be an underpinning of mathematical learning disorder (MLD). Thus, one aim of the present study was to perform an exploratory correlational analysis between performance on pediatric neuropsychological tasks of procedural learning and a classification of MLD. The second aim was to utilize regression analysis of measures of procedural learning for predicting a clinically useful classification of MLD. Results revealed a significant correlation between performance on tasks of procedural learning and a classification of MLD. The follow-up regression model yielded the most predictive variables in identifying individuals with MLD, which included: (a) WISC-V Coding; (b) first administration of Trail Making Test Part B; (c) slope across five serial administrations of Trail Making Test Part B. The model was highly significant and had a classification accuracy for MLD of 87.4%. Results suggest performance on procedural learning tasks significantly predict a classification of MLD. Theoretical and clinical implications are discussed.

Automaticity and Executive Abilities in Developmental Dyslexia: A Theoretical Review

Cognitive difficulties are well documented in developmental dyslexia but they present a challenge to dyslexia theory. In this paper, the Model of the Control of Action is proposed as a theoretical explanation of how and why deficits in both automaticity and executive abilities are apparent in the cognitive profiles of dyslexia and how these deficits might relate to literacy difficulties. This theoretical perspective is used to consider evidence from different cognitive domains. The neuroanatomical underpinnings of automaticity and executive abilities are then discussed in relation to the understanding of dyslexia. Links between reading, writing, and executive function are considered. The reviewed evidence suggests that dyslexia theory should consider an interaction between procedural learned behaviour (automaticity) and higher-order (executive) abilities. The capacity to handle environmental interference, develop and engage adaptive strategies accordingly, and plan actions all require interactions between the cerebellum and the prefrontal cortex (PFC). Difficulties in these areas might explain both impairments in the cumulative development of literacy skills in childhood and general task management in everyday life in adulthood. It is suggested that improved measures are required to assess this cerebellar–PFC interaction and to allow early identification of future literacy difficulties, allowing implementation of timely interventions and reasonable adjustments.

Sound omission related brain responses in children

Action is an important way for children to learn about the world. Recent theories suggest that action is inherently accompanied by the sensory prediction of its effects. Such predictions can be revealed by rarely omitting the expected sensory consequence of the action, resulting in an omission response that is observable in the EEG. Although prediction errors play an important role in models of learning and development, little is known about omission-related brain responses in children. This study used a motor-auditory omission paradigm, testing a group of 6-8-year-old children and an adult group (N = 31 each). In an identity-specific condition, the sound coupled to the motor action was predictable, while in an identity unspecific condition the sound was unpredictable. Results of a temporal principal component analysis revealed that sound-related brain responses underlying the N1-complex differed considerably between age groups. Despite these developmental differences, omission responses (oN1) were similar between age groups. Two subcomponents of the oN1 were differently affected by specific and unspecific predictions. Results demonstrate that children, independent from the maturation of sound processing mechanisms, can implement specific and unspecific predictions as flexibly as adults. This supports theories that regard action and prediction error as important drivers of cognitive development.

Aberrant Auditory and Visual Memory Development of Children with Upper Limb Motor Disorders

The current study aimed to compare differences in the cognitive development of children with and without upper limb motor disorders. The study involved 89 children from 3 to 15 years old; 57 children with similar upper limb motor disorders and 32 healthy children. Our results showed that motor disorders could impair cognitive functions, especially memory. In particular, we found that children between 8 and 11 years old with upper limb disorders differed significantly from their healthy peers in both auditory and visual memory scales. These results can be explained by the fact that the development of cognitive functions depends on the normal development of motor skills, and the developmental delay of motor skills affects cognitive functions. Correlation analysis did not reveal any significant relationship between other cognitive functions (attention, thinking, intelligence) and motor function. Altogether, these findings point to the need to adapt general habilitation programs for children with motor disorders, considering the cognitive impairment during their development. The evaluation of children with motor impairment is often limited to their motor dysfunction, leaving their cognitive development neglected. The current study showed the importance of cognitive issues for these children. Moreover, early intervention, particularly focused on memory, can prevent some of the accompanying difficulties in learning and daily life functioning of children with movement disorders.

fNIRS Monitoring of Infant Prefrontal Cortex During Crawling and an Executive Functioning Task

Functional near-infrared spectroscopy (fNIRS)is a brain-imaging technology used to reveal brain activity by measuring blood oxygenation. Using fNIRS we measured activity in the left prefrontal lobe of 8–14 month-old infants as they crawled or were pushed in a stroller and as they were given a passive attention task or an active executive function (EF) task. For each task, we measured peak total hemoglobin concentration and peak Oxy relative to baseline. Results revealed differences in peak Oxy levels for crawling vs. strolling and between the EF and passive cognitive tasks, with total hemoglobin greater for the EF task than the passive attention task. These results support the theoretical view that both active locomotion and EF engage the prefrontal cortex (PFC) during early development.

A Network Perspective on the Relationship Between Moderate to Vigorous Physical Activity and Fundamental Motor Skills in Early Childhood

BACKGROUND

The relationship between moderate to vigorous physical activity (MVPA) and fundamental motor skill (FMS) is inconsistent in early childhood, due to its complex and nonlinear characteristics. This study aimed to analyze the nonlinear relationships between MVPA, FMS, body mass index (BMI), sex, and age in preschoolers.

METHODS

This cross-sectional study with preschoolers (n = 204; 4.0 [0.8] y old; 99 boys), provided objective physical activity data, FMS assessments, and BMI. The associations between MVPA, FMS, BMI, sex, and age were explored using the network analysis (RStudio and qgraph).

RESULTS

Boys were more motor competent than girls in all FMS skills, while girls were more active than boys during the weekend. Older children were less active than their younger peers during these days. MVPA is weak and differently related to each FMS, and the leap skill emerged with the highest betweenness and strength values in the network.

CONCLUSIONS

For the assessed preschoolers, when considering BMI, age, and sex, the relationships between MVPA and FMS are inconsistent, and leap emerged as the main variable. During early childhood, these variables are connected as part of a complex system in which each skill has a dynamic role within the emerging pattern.

Event Segmentation Deficits in ADHD

Event segmentation is the automatic cognitive process of chunking ongoing information into meaningful events. Event segmentation theory (EST) proposes that event segmentation is a grouping process fundamental to normal, everyday perceptual processing, taking a central role in attention and action control. The neurocognitive deficits observed among individuals with ADHD overlap those involved in event segmentation, but to date no research has examined event segmentation in the context of ADHD. Objective: The goal of this study was to document the event segmentation deficits of individuals with ADHD. Method: Seventy-five undergraduates with ADHD and seventy-nine without ADHD performed an event segmentation task. Results: Results revealed that undergraduates with ADHD identify significantly more large events. Conclusion: These findingssuggest explicit disturbances in the event model and updating system among those with ADHD. Future research directions include further elucidating these deficits with more varied stimuli and establishing associations with functional impairments.

Executive function in children with and without developmental coordination disorder: A comparative study

BACKGROUND

Children with motor impairments also show poor performance in some executive functions' components. However, there is no consensus on which specific executive subdomain is more impacted.

AIM

The objective of this study was to compare executive functions in children with developmental coordination disorder (DCD), at risk for DCD (r-DCD), and in typically developing (TD) children.

METHODS AND PROCEDURES

A sample of 397 children was assessed using the MABC-2. Two groups of children were identified; DCD (n = 63) and at r-DCD (n = 31). A third matched group of children with TD (n = 63) was formed. The MABC-2 checklist and the WASI tests were used as screening tools. Measures of executive function including verbal and nonverbal tasks for working memory, inhibitory control, and cognitive flexibility were tested. Multivariate analysis of variance followed by analyses of variance and Bonferroni tests were used to verify group effects on executive functions.

RESULTS

A significant group effects were found for Working Memory, Λ = .78, F(4, 360) = 10.12, p ≤ .001, η_p² = .12; Inhibitory Control, Λ = .59, F(16, 294) = 5.48, p ≤ .001, η_p² = .23; and Cognitive Flexibility and Inhibitory Control, Λ = .60, F(22, 288) = 3.74, p ≤ .001, η_p² = .22, with moderate effect sizes. The DCD group showed lower scores compared with the TD group on the visuospatial and verbal working memory; inhibitory control and in tasks of cognitive flexibility; the r-DCD group showed lower scores compared with the TD group for visuospatial working memory and for cognitive flexibility.

CONCLUSIONS AND IMPLICATIONS

Poor performance in several measures of executive functions in children with DCD emphasized the need of motor/executive task-specific interventions. Furthermore, children at r-DCD showed low scores in several executive functions; therefore, preventive services should also be provided for this subclinical group.

How the motor system integrates with working memory

Working memory is vital for basic functions in everyday life. During working memory, one holds a finite amount of information in mind until it is no longer required or when resources to maintain this information are depleted. Convergence of neuroimaging data indicates that working memory is supported by the motor system, and in particular, by regions that are involved in motor planning and preparation, in the absence of overt movement. These "secondary motor" regions are physically located between primary motor and non-motor regions, within the frontal lobe, cerebellum, and basal ganglia, creating a functionally organized gradient. The contribution of secondary motor regions to working memory may be to generate internal motor traces that reinforce the representation of information held in mind. The primary aim of this review is to elucidate motor-cognitive interactions through the lens of working memory using the Sternberg paradigm as a model and to suggest origins of the motor-cognitive interface. In addition, we discuss the implications of the motor-cognitive relationship for clinical groups with motor network deficits.

Cerebellar development and its mediation role in cognitive planning in childhood

Recent evidence suggests that the cerebellum contributes not only to the planning and execution of movement but also to the high-order cognitive planning. Childhood is a critical period for development of the cerebellum and cognitive planning. This study aimed (a) to examine the development of cerebellar morphology and microstructure and (b) to examine the cerebellar mediation roles in the relationship between age and cognitive planning in 6- to 10-year-old children (n = 126). We used an anatomical parcellation to quantify cerebellar regional gray matter (GM) and white matter (WM) volumes, and WM microstructure, including fractional anisotropy (FA) and mean diffusivity (MD). We assessed planning ability using the Stockings of Cambridge (SOC) task in all children. We revealed (a) a measure-specific anterior-to-posterior gradient of the cerebellar development in childhood, that is, smaller GM volumes and greater WM FA of the anterior segment of the cerebellum but larger GM volumes and lower WM FA in the posterior segment of the cerebellum in older children; (b) an age-related improvement of the SOC performance at the most demanding level of five-move problems; and (c) a mediation role of the lateral cerebellar WM volumes in age-related improvement in the SOC performance in childhood. These results highlight the differential development of the cerebellum during childhood and provide evidence that brain adaptation to the acquisition of planning ability during childhood could partially be achieved through the engagement of the lateral cerebellum.

White matter network topology relates to cognitive flexibility and cumulative neurological risk in adult survivors of pediatric brain tumors

Adult survivors of pediatric brain tumors exhibit deficits in executive functioning. Given that brain tumors and medical treatments for brain tumors result in disruptions to white matter, a network analysis was used to explore the topological properties of white matter networks. This study used diffusion tensor imaging and deterministic tractography in 38 adult survivors of pediatric brain tumors (mean age in years = 23.11 (SD = 4.96), 54% female, mean years post diagnosis = 14.09 (SD = 6.19)) and 38 healthy peers matched by age, gender, handedness, and socioeconomic status. Nodes were defined using the Automated Anatomical Labeling (AAL) parcellation scheme, and edges were defined as the mean fractional anisotropy of streamlines that connected each node pair. Global efficiency and average clustering coefficient were reduced in survivors compared to healthy peers with preferential impact to hub regions. Global efficiency mediated differences in cognitive flexibility between survivors and healthy peers, as well as the relationship between cumulative neurological risk and cognitive flexibility. These results suggest that adult survivors of pediatric brain tumors, on average one and a half decades post brain tumor diagnosis and treatment, exhibit altered white matter topology in the form of suboptimal integration and segregation of large scale networks, and that disrupted topology may underlie executive functioning impairments. Network based studies provided important topographic insights on network organization in long-term survivors of pediatric brain tumor.

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Long term brain tumor survivorship is associated with altered white matter networks.

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Hub regions were preferentially impacted in survivors.

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Network properties explain cognitive flexibility differences between survivors and peers.

Asynchronous Development of Cerebellar, Cerebello-Cortical, and Cortico-Cortical Functional Networks in Infancy, Childhood, and Adulthood

Evidence from clinical studies shows that early cerebellar injury can cause abnormal development of the cerebral cortex in children. Characterization of normative development of the cerebellar and cerebello-cortical organization in early life is of great clinical importance. Here, we analyzed cerebellar, cerebello-cortical, and cortico-cortical functional networks using resting-state functional magnetic resonance imaging data of healthy infants (6 months, n = 21), children (4-10 years, n = 68), and adults (23-38 years, n = 25). We employed independent component analysis and identified 7 cerebellar functional networks in infants and 12 in children and adults. We revealed that the cerebellum was functionally connected with the sensorimotor cortex in infants but with the sensorimotor, executive control, and default mode systems of the cortex in children and adults. The functional connectivity strength in the cerebello-cortical functional networks of sensorimotor, executive control, and default mode systems was the strongest in middle childhood, but was weaker in adulthood. In contrast, the functional coherence of the cortico-cortical networks was stronger in adulthood. These findings suggest early synchronization of the cerebello-cortical networks in infancy, particularly in the early developing primary sensorimotor system. Conversely, age-related differences of cerebellar, cerebello-cortical, and cortico-cortical functional networks in childhood and adulthood suggest potential asynchrony of the cerebellar and cortical functional maturation.

Trade-off of cerebello-cortical and cortico-cortical functional networks for planning in 6-year-old children

Childhood is a critical period for the development of cognitive planning. There is a lack of knowledge on its neural mechanisms in children. This study aimed to examine cerebello-cortical and cortico-cortical functional connectivity in association with planning skills in 6-year-olds (n = 76). We identified the cerebello-cortical and cortico-cortical functional networks related to cognitive planning using activation likelihood estimation (ALE) meta-analysis on existing functional imaging studies on spatial planning, and data-driven independent component analysis (ICA) of children's resting-state functional MRI (rs-fMRI). We investigated associations of cerebello-cortical and cortico-cortical functional connectivity with planning ability in 6-year-olds, as assessed using the Stockings of Cambridge task. Long-range functional connectivity of two cerebellar networks (lobules VI and lateral VIIa) with the prefrontal and premotor cortex were greater in children with poorer planning ability. In contrast, cortico-cortical association networks were not associated with the performance of planning in children. These results highlighted the key contribution of the lateral cerebello-frontal functional connectivity, but not cortico-cortical association functional connectivity, for planning ability in 6-year-olds. Our results suggested that brain adaptation to the acquisition of planning ability during childhood is partially achieved through the engagement of the cerebello-cortical functional connectivity.

Contingent Negative Variation and Working Memory Maintenance in Adolescents with Low and High Motor Competencies

Although it has been suggested that motor and cognitive development is interrelated, the link between motor competencies and neurophysiological indices of working memory operations has not yet been examined in adolescents. This study is aimed at comparing contingent negative variation and working memory performance between adolescents with low and high motor competencies. In eighty-two adolescents, motor competencies were assessed with the MOBAK-5 (basic motor competencies, 5th grade) test battery and a median split was performed on this variable to divide them into low and high performers. Additionally, all participants completed a Sternberg paradigm to assess working memory maintenance. The initial (iCNV) and terminal (tCNV) components of the contingent negative variation elicited by the cognitive task were recorded using electroencephalography. Higher working memory maintenance was found in adolescents with high motor competencies compared to those with low motor competencies. Cluster-based permutation testing further revealed increased iCNV in adolescents with higher motor competencies. In contrast, there was no difference in tCNV between groups. The findings suggest that high working memory maintenance and effective task preparation are both linked to high motor competencies. Thus, high performers on complex motor tasks seem to rely more on a proactive control strategy, which is optimal in tasks with high working memory demands.

Infant Neuromotor Development and Childhood Problem Behavior

BACKGROUND

Research of adults and school-aged children suggest a neurodevelopmental basis for psychiatric disorders. We examined whether infant neuromotor development predicted internalizing and externalizing problems in young children.

METHODS

In Generation R, a population-based cohort in the Netherlands (2002-2006), trained research assistants evaluated the neuromotor development of 4006 infants aged 2 to 5 months by using an adapted version of Touwen's Neurodevelopmental Examination (tone, responses, and senses and other observations). We defined nonoptimal neuromotor development as scores in the highest tertile. Mothers and fathers rated their children's behavior at ages 1.5, 3, 6, and 10 years with the Child Behavior Checklist (n = 3474, response: 86.7%). The associations were tested with generalized linear mixed models.

RESULTS

Overall, neuromotor development predicted internalizing scores, but no association was observed with externalizing scores. Nonoptimal muscle tone was associated with higher internalizing scores (mothers' report: β = .07; 95% confidence interval [CI]: 0.01 to 0.13; fathers' report: β = .09, 95% CI: 0.00 to 0.16). In particular, nonoptimal low muscle tone was associated with higher internalizing scores (mothers' report: β = .11; 95% CI: 0.05 to 0.18; fathers' report: β = .13; 95% CI: 0.04 to 0.22). We also observed an association between senses and other observations with internalizing scores. There was no relationship between high muscle tone or reflexes and internalizing scores.

CONCLUSIONS

Common emotional problems in childhood have a neurodevelopmental basis in infancy. Neuromotor assessment in infancy may help identify vulnerability to early internalizing symptoms and offer the opportunity for targeted interventions.

Relationship of cognitive functions and gross motor abilities in children with spastic diplegic cerebral palsy

Spastic diplegic cerebral palsy can be accompanied by a myriad of symptoms affecting other body systems including cognitive dysfunction. The purpose of this study was to determine whether a relationship exists between cognitive functions in the form of selective attention and figural memory domains with standing and walking motor abilities in children with diplegic cerebral palsy. The research design was a correlational study. Tasks assessing cognitive function and gross motor abilities were carried out with a sample of 50 children. The data demonstrated the presence of correlation between selective attention and figural memory domains of cognitive function with standing, walking running, and jumping subscales of the Gross Motor Function Measure (GMFM) scale at different ages, and this correlation was significant between selective attention domain and gross motor abilities. The outcome measurements of the current study provide original evidence based on the necessity of including cognitive and physical impairments in the examination and evaluation of children with diplegic cerebral palsy in research and clinical settings.

Cerebellar fMRI Activation Increases with Increasing Working Memory Demands

The aim of the present study was to explore cerebellar contributions to the central executive in n-back working memory tasks using 7-T functional magnetic imaging (fMRI). We hypothesized that cerebellar activation increased with increasing working memory demands. Activations of the cerebellar cortex and dentate nuclei were compared between 0-back (serving as a motor control task), 1-back, and 2-back working memory tasks for both verbal and abstract modalities. A block design was used. Data of 27 participants (mean age 26.6 ± 3.8 years, female/male 12:15) were included in group statistical analysis. We observed that cerebellar cortical activations increased with higher central executive demands in n-back tasks independent of task modality. As confirmed by subtraction analyses, additional bilateral activations following higher executive demands were found primarily in four distinct cerebellar areas: (i) the border region of lobule VI and crus I, (ii) inferior parts of the lateral cerebellum (lobules crus II, VIIb, VIII, IX), (iii) posterior parts of the paravermal cerebellar cortex (lobules VI, crus I, crus II), and (iv) the inferior vermis (lobules VI, VIIb, VIII, IX). Dentate activations were observed for both verbal and abstract modalities. Task-related increases were less robust and detected for the verbal n-back tasks only. These results provide further evidence that the cerebellum participates in an amodal bilateral neuronal network representing the central executive during working memory n-back tasks.

Cerebellar Symptoms Are Associated With Omission Errors and Variability of Response Time in Children With ADHD

OBJECTIVE

We examined the presence of cerebellar symptoms in ADHD and their association with behavioral markers of this disorder.

METHOD

Sixty-two children with ADHD and 62 typically developing (TD) children were examined for cerebellar symptoms using the ataxia rating scale and tested using Conners' Continuous Performance Test.

RESULTS

Children with ADHD had significantly more cerebellar symptoms compared with the TD children. Cerebellar symptom scores decreased with age in the ADHD group; in the TD group remained stable. In both groups, cerebellar symptoms were associated with parent-rated hyperactive/impulsive symptoms, variability of response time standard error (RT-SE) and increase of RT-SE as the test progresses. More variables were associated with cerebellar symptoms in the ADHD group including omission errors, overall RT-SE and its increase for prolonged interstimulus intervals.

CONCLUSION

Our results highlight the importance of research into motor functions in children with ADHD and indicate a role for cerebellar impairment in this disorder.

Physically Active Math and Language Lessons Improve Academic Achievement: A Cluster Randomized Controlled Trial

OBJECTIVES

Using physical activity in the teaching of academic lessons is a new way of learning. The aim of this study was to investigate the effects of an innovative physically active academic intervention ("Fit & Vaardig op School" [F&V]) on academic achievement of children.

METHODS

Using physical activity to teach math and spelling lessons was studied in a cluster-randomized controlled trial. Participants were 499 children (mean age 8.1 years) from second- and third-grade classes of 12 elementary schools. At each school, a second- and third-grade class were randomly assigned to the intervention or control group. The intervention group participated in F&V lessons for 2 years, 22 weeks per year, 3 times a week. The control group participated in regular classroom lessons. Children's academic achievement was measured before the intervention started and after the first and second intervention years. Academic achievement was measured by 2 mathematics tests (speed and general math skills) and 2 language tests (reading and spelling).

RESULTS

After 2 years, multilevel analysis showed that children in the intervention group had significantly greater gains in mathematics speed test (P < .001; effect size [ES] 0.51), general mathematics (P < .001; ES 0.42), and spelling (P < .001; ES 0.45) scores. This equates to 4 months more learning gains in comparison with the control group. No differences were found on the reading test.

CONCLUSIONS

Physically active academic lessons significantly improved mathematics and spelling performance of elementary school children and are therefore a promising new way of teaching.

Better Movers and Thinkers (BMT): An Exploratory Study of an Innovative Approach to Physical Education

Recent research has confirmed a positive relationship between levels of physical activity and academic achievement. Some of these studies have been informed by neurological models of Executive Functioning (EF). There is a general consensus within the literature that the three core EF skills are; working memory, inhibitory control and cognitive flexibility. The development of these core EF skills has been linked with learning and academic achievement and is an essential component in the delivery of PE using a new and innovative approach called ‘Better Movers and Thinkers (BMT).’ A mixed methods design was used to investigate the effectiveness and feasibility of a 16-week intervention programme using BMT where 46 children were tested on two separate occasions for coordination and balance control, academic skills, working memory and non-verbal reasoning skills. One school acted as the control condition (21 students, aged 9 – 10 years) and another school acted as the intervention condition (25 students, aged 9 – 10 years). Quantitative data revealed an effect between pre and post-test conditions in the areas of phonological skills (p = .042), segmentation skills (p = .014) and working memory (p = .040) in favour of the intervention condition. Further analysis identified a gender-interaction with male students in the intervention condition making significant gains in phonological skills (p = .005) segmentation skills (p = .014) and spelling (p = .007) compared to boys in the control condition. Analysis of qualitative data from a sample of students from the intervention condition and their class teacher indicated good acceptability of BMT as an alternative approach to PE.

Relation of infant motor development with nonverbal intelligence, language comprehension and neuropsychological functioning in childhood: a population-based study

Within a population-based study of 3356 children, we investigated whether infant neuromotor development was associated with cognition in early childhood. Neuromotor development was examined with an adapted version of Touwen's Neurodevelopmental Examination between 9 and 20 weeks. Parents rated their children's executive functioning at 4 years. At age 6 years, children performed intelligence and language comprehension tests, using Dutch test batteries. At age 6-9 years, neuropsychological functioning was assessed in 486 children using the validated NEPSY-II-NL test battery. We showed that less optimal neurodevelopment in infancy may predict poor mental rotation, immediate memory, shifting, and planning; but not nonverbal intelligence or language comprehension.

Building an adaptive brain across development: targets for neurorehabilitation must begin in infancy

Much progress has been made toward behavioral and pharmacological intervention in intellectual disability, which was once thought too difficult to treat. Down syndrome (DS) research has shown rapid advances, and clinical trials are currently underway, with more on the horizon. Here, we review the literature on the emergent profile of cognitive development in DS, emphasizing that treatment approaches must consider how some "end state" impairments, such as language deficits, may develop from early alterations in neural systems beginning in infancy. Specifically, we highlight evidence suggesting that there are pre- and early postnatal alterations in brain structure and function in DS, resulting in disturbed network function across development. We stress that these early alterations are likely amplified by Alzheimer's disease (AD) progression and poor sleep. Focusing on three network hubs (prefrontal cortex, hippocampus, and cerebellum), we discuss how these regions may relate to evolving deficits in cognitive function in individuals with DS, and to their language profile in particular.

Relationship between motor skill competency and executive function in children with Down's syndrome

BACKGROUND

Previous studies suggest that children with Down's syndrome (DS), a genetically based neurodevelopmental disorder, demonstrate motor problems and cognitive deficits. The first aim of this study was to examine motor skills and executive functions (EFs) in school-age children with DS. The second aim was to investigate the relationship between these two performance domains.

METHODS

The Test of Gross Motor Development (TGMD-2), the Movement Assessment Battery Children-2 checklist (MABC2-checklist) and the Trail-Making Test for young children (Trails-P) were used to assess motor and cognitive performances of 18 children (11 boys, 7 girls) with DS aged between 7 and 11 years (9.06 ± 0.96) and an age- and sex-matched sample of 18 typically developing (TD) children (11 boys, 7 girls; 8.99 ± 0.93).

RESULTS

Individuals with DS showed the expected difficulties in attentional control, response suppression and distraction, as well as in locomotor and object control skills, as indicated by poorer performance than TD individuals. Motor performance (bottom-up as well as top-down measures) and EF correlated positively, with regard to the group with DS only though. In the most complex task (distraction), the children of the DS group achieving lower locomotor scores showed lower efficacy scores on the Trails-P. Additionally, strong relationships were found for the perspective of teachers on all sections of the MABC2-Checklist and EF.

CONCLUSION

The findings from this study suggest that children with DS are not only impaired in higher-order EF, but showing also deficits in locomotor and object control skills. This study stresses the importance of early interventions facilitating cognitive abilities and motor skills.

The Epidemiology and Associated Phenomenology of Formal Thought Disorder: A Systematic Review

BACKGROUND

Authors of the Diagnostic and Statistical Manual, Fifth Edition (DSM-V) have recommended to "integrate dimensions into clinical practice." The epidemiology and associated phenomenology of formal thought disorder (FTD) have been described but not reviewed. We aimed to carry out a systematic review of FTD to this end.

METHODS

A systematic review of FTD literature, from 1978 to 2013, using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

A total of 881 abstracts were reviewed and 120 articles met inclusion criteria; articles describing FTD factor structure (n = 15), prevalence and longitudinal course (n = 41), role in diagnosis (n = 22), associated clinical variables (n = 56), and influence on outcome (n = 35) were included. Prevalence estimates for FTD in psychosis range from 5% to 91%. Dividing FTD into domains, by factor analysis, can accurately identify 91% of psychotic diagnoses. FTD is associated with increased clinical severity. Poorer outcomes are predicted by negative thought disorder, more so than the typical construct of "disorganized speech."

CONCLUSION

FTD is a common symptom of psychosis and may be considered a marker of illness severity. Detailed dimensional assessment of FTD can clarify diagnosis and may help predict prognosis.

Multifactorial determinants of cognition - Thyroid function is not the only one

Background

Since the 1960s hypothyroidism together with iodine deficiency have been considered to be a principal determinant of cognition development. Following iodine supplementation programs and improved treatment options for hypothyroidism this relation might not be valid in 2015. On the other hand neurosciences have added different inputs also related to cognition.

Scope of review

We will examine the characteristics of the original and current publications on thyroid function and cognition and also add some general determinants of intelligence and cognition. One central issue for us is the relation of stress to cognition knowing that both physical and psychological stress, are frequent elements in subjects with thyroid dysfunction. We have considered a special type of stress called pre-natal stress which can influence cognitive functions. Fear and anxiety can be intermingled requiring mechanisms of fear extinction.

Major conclusions

Recent studies have failed to show an influence of thyroid medication during pregnancy on intellectual development. Neuroscience offers a better explanation of cognition than hypothyroidism and iodine deficiency. Additional factors relevant to cognition are nutrition, infection, prenatal stress, and early life stress. In turn stress is related to low magnesium levels. Magnesium supplementation can correct both latent hypothyroidism and acquired mild cognitive deficits.

General significance

Cognition is a complex process that depends on many determinants and not only on thyroid function. Magnesium deficiency appears to be a basic mechanism for changes in thyroid function as well as of cognition.

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Untreated hypothyroidism, i.e. hypothyroxinemia, can influence IQ.

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Thyroxine administration to euthyroid pregnant women has no effect on cognition.

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The hippocampus and NMDA receptors play a central role in cognitive processes.

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Antenatal and early life stressors can influence cognition later in life.

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Stressors can lead to decreased levels of magnesium and demands supplementation.

The interrelation between sensorimotor abilities, cognitive performance and individual EEG alpha peak frequency in young children

OBJECTIVE

The aim of this study was to identify the interrelation between sensorimotor abilities, cognitive performance and individual alpha peak frequency (iAPF), an EEG marker of global architectural and functional properties of the human brain, in healthy preschool children.

METHODS

25 participants completed a one minute eyes-closed EEG recording, two cognitive tests assessing processing speed and visual working memory and a sensorimotor test battery.

RESULTS

We found positive correlations between selective sensorimotor abilities and iAPF; however, no significant correlations were observed between iAPF and cognitive performance. Specifically, locomotor skills correlated with iAPF across all cortical regions, except for the occipital cortex. Furthermore, a close relationship was found between sensorimotor and cognitive performance indicating that children with improved sensorimotor abilities were faster and/or more accurate in cognitive task performance. The cumulative pattern of our results indicates that a close relationship exists between sensorimotor and cognitive performance in young children. However, this relationship is dissociated from the iAPF.

CONCLUSION

In contrast to adults, in young children the iAPF is related to locomotor skills and not to cognitive processing speed or visual working memory function.

SIGNIFICANCE

The global architectural and functional properties of the brain are closely related to locomotor skills during development.

The effectiveness of racket-sport intervention on visual perception and executive functions in children with mild intellectual disabilities and borderline intellectual functioning

BACKGROUND

This study aimed to investigate the effects of table tennis training (TTT) versus standard occupational therapy (SOT) on visual perception and executive functions in school-age children with mild intellectual disabilities and borderline intellectual functioning.

SUBJECTS AND METHODS

Children (n=91) were randomly assigned to intervention with either SOT (n=46, 20 females, mean age =10.9±3.9 years) or TTT (n=45, 21 females, mean age =10.6±3.6 years), while another 41 (18 females, mean age =10.7±4.0 years) served as controls. Both the SOT and TTT programs were administered 60 minutes per session, three times a week, for 16 weeks. The Test of Visual Perceptual Skill-third edition (TVPS-3) was used to evaluate visual perception, and executive functions were assessed by the Wisconsin Card Sorting Test 64-card version (WCST-64) and the Stroop test.

RESULTS

At postintervention, the two intervention groups significantly outperformed the control group on all measures of visual perception and executive functions. Participants in the TTT group had significantly greater before-after changes on all measures of the TVPS-3, WCST-64, and the Stroop test compared to the SOT and controls.

CONCLUSION

Table tennis could be considered a therapy option while treating cognitive/perceptual problems in children with mild intellectual disabilities and borderline intellectual functioning. Implications for clinical professionals and recommendations for further research are discussed.

Large-scale brain systems and subcortical relationships: practical applications

This article describes an interactive paradigm for understanding brain functioning. This model requires both explicit and implicit learning processes. This paradigm is illustrated through the interpretation of practical examples of behavior. Applications of current neuropsychological tests are presented within this interactive paradigm. The development of new neuropsychological tests is presented, as derived from experimental test paradigms that evaluate implicit learning processes.

A longitudinal study on the relationship between duration of untreated psychosis and executive function in early-onset first-episode psychosis

BACKGROUND

The relationship between duration of untreated psychosis (DUP) and executive function (EF) in patients with first-episode psychosis (FEP) is controversial. We aim to assess the influence of DUP on changes in EF over a 2-year period in subjects with early-onset FEP (first psychotic symptom before age 18) and less than 6 months of positive symptoms.

METHODS

A total of 66 subjects were included in the study (19 females [28.8%], mean age 16.2 ± 1.6 years). The influence of DUP on changes in EF over the 2-year follow-up (expressed as a composite score of 5 cognitive abilities: attention, working memory, cognitive flexibility, response inhibition, and problem solving) was estimated using a multivariate linear regression model after removing the effect of intelligence quotient and controlling for age, gender, diagnosis, premorbid adjustment, severity of positive and negative symptoms at baseline, global functioning at baseline, and mean daily antipsychotic dosage during follow-up.

RESULTS

Mean DUP was 65.0 ± 6.9 days (95% confidence interval [CI], 51.2, 78.8). Median DUP was 47.5 days (range 2-180 days). Negative symptoms at baseline was the only variable significantly associated with EF at baseline (10.9% of explained variance [e.v. 10.9%], p=0.007). Only shorter DUP (e.v. 8.7%, p=0.013) and greater severity of baseline negative symptoms (e.v. 10.0%, p=0.008) were significantly associated with greater improvement in EF.

CONCLUSIONS

In early-onset FEP, shorter DUP was associated with greater improvement in EF over a 2-year follow-up period.

Transcranial cerebellar direct current stimulation and transcutaneous spinal cord direct current stimulation as innovative tools for neuroscientists

Two neuromodulatory techniques based on applying direct current (DC) non-invasively through the skin, transcranial cerebellar direct current stimulation (tDCS) and transcutaneous spinal DCS, can induce prolonged functional changes consistent with a direct influence on the human cerebellum and spinal cord. In this article we review the major experimental works on cerebellar tDCS and on spinal tDCS, and their preliminary clinical applications. Cerebellar tDCS modulates cerebellar motor cortical inhibition, gait adaptation, motor behaviour, and cognition (learning, language, memory, attention). Spinal tDCS influences the ascending and descending spinal pathways, and spinal reflex excitability. In the anaesthetised mouse, DC stimulation applied under the skin along the entire spinal cord may affect GABAergic and glutamatergic systems. Preliminary clinical studies in patients with cerebellar disorders, and in animals and patients with spinal cord injuries, have reported beneficial effects. Overall the available data show that cerebellar tDCS and spinal tDCS are two novel approaches for inducing prolonged functional changes and neuroplasticity in the human cerebellum and spinal cord, and both are new tools for experimental and clinical neuroscientists.