Localized alterations in cortical thickness and sulcal depth of the cingulo-opercular network in relation to lower reading fluency skills in children with dyslexia

The traditional models of reading development describe how language processing and word decoding contribute to reading comprehension and how impairments in word decoding, a defining feature of dyslexia, affect reading comprehension outcomes. However, these models do not include word and sentence reading (contextual reading) fluency, both of which engage executive functions, with notably decreased performance in children with dyslexia. In the current study, we compared cortical thickness and sulcal depth (CT/SD) in the cingulo-opercular (CO) executive functions brain network in children with dyslexia and typical readers and examined associations with word vs. contextual reading fluency. Overall, CT was lower in insular regions and higher in parietal and caudal anterior cingulate cortex regions in children with dyslexia. Children with dyslexia showed positive correlations between word reading fluency and CT/SD in insular regions, whereas no significant correlations were observed in typical readers. For sentence reading fluency, negative correlations with CT/SD were found in insular regions in children with dyslexia, while positive correlations with SD were found in insular regions in typical readers. These results demonstrate the differential relations between word and sentence reading fluency and anatomical circuitry supporting executive functions in children with dyslexia vs. typical readers. It also suggests that word and sentence reading fluency, relate to morphology of executive function-related regions in children with dyslexia, whereas in typical readers, only sentence reading fluency relates to morphology of executive function regions. The results also highlight the role of the insula within the CO network in reading fluency. Here we suggest that word and sentence reading fluency are distinct components of reading that should each be included in the Simple View of Reading traditional model.

Greater utilization of executive functions networks when listening to stories with visual stimulation is related to lower reading abilities in children

Narrative comprehension relies on basic sensory processing abilities, such as visual and auditory processing, with recent evidence for utilizing executive functions (EF), which are also engaged during reading. EF was previously related to the "supporter" of engaging the auditory and visual modalities in different cognitive tasks, with evidence of lower efficiency in this process among those with reading difficulties in the absence of a visual stimulus (i.e. while listening to stories). The current study aims to fill out the gap related to the level of reliance on these neural circuits while visual aids (pictures) are involved during story listening in relation to reading skills. Functional MRI data were collected from 44 Hebrew-speaking children aged 8-12 years while listening to stories with vs without visual stimuli (i.e., pictures). Functional connectivity of networks supporting reading was defined in each condition and compared between the conditions against behavioral reading measures. Lower reading skills were related to greater functional connectivity values between EF networks (default mode and memory networks), and between the auditory and memory networks for the stories with vs without the visual stimulation. A greater difference in functional connectivity between the conditions was related to lower reading scores. We conclude that lower reading skills in children may be related to a need for greater scaffolding, i.e., visual stimulation such as pictures describing the narratives when listening to stories, which may guide future intervention approaches.

An executive-functions-based reading training enhances sensory-motor systems integration during reading fluency in children with dyslexia

The Simple View of Reading model suggests that intact language processing and word decoding lead to proficient reading comprehension, with recent studies pointing at executive functions as an important component contributing to reading proficiency. Here, we aimed to determine the underlying mechanism(s) for these changes. Participants include 120 8- to 12-year-old children (n = 55 with dyslexia, n = 65 typical readers) trained on an executive functions-based reading program, including pre/postfunctional MRI and behavioral data collection. Across groups, improved word reading was related to stronger functional connections within executive functions and sensory networks. In children with dyslexia, faster and more accurate word reading was related to stronger functional connections within and between sensory networks. These results suggest greater synchronization of brain systems after the intervention, consistent with the "neural noise" hypothesis in children with dyslexia and support the consideration of including executive functions as part of the Simple View of Reading model.

Parent-child couples display shared neural fingerprints while listening to stories

Neural fingerprinting is a method to identify individuals from a group of people. Here, we established a new connectome-based identification model and used diffusion maps to show that biological parent-child couples share functional connectivity patterns while listening to stories. These shared fingerprints enabled the identification of children and their biological parents from a group of parents and children. Functional patterns were evident in both cognitive and sensory brain networks. Defining "typical" shared biological parent-child brain patterns may enable predicting or even preventing impaired parent-child connections that develop due to genetic or environmental causes. Finally, we argue that the proposed framework opens new opportunities to link similarities in connectivity patterns to behavioral, psychological, and medical phenomena among other populations. To our knowledge, this is the first study to reveal the neural fingerprint that represents distinct biological parent-child couples.

Language First, Cognition Later: Different Trajectories of Subcomponents of the Future-Reading Network in Processing Narratives from Kindergarten to Adolescence

Narrative comprehension is a linguistic ability that emerges early in life and has a critical role in language development, reading acquisition, and comprehension. According to the Simple View of Reading model, reading is acquired through word decoding and linguistic comprehension. Here, within and between networks, functional connectivity in several brain networks supporting both language and reading abilities was examined from prereading to proficient reading age in 32 healthy children, ages 5-18 years, scanned annually while listening to stories over 12 years. Functional connectivity changes within and between the networks were assessed and compared between the years using hierarchical linear regression and were related to reading abilities. At prereading age, the networks related to basic language processing accounted for 32.5% of the variation of reading ability at reading age (at 12-14 years) (R2 = 0.325, p = 0.05). At age 17, more complex cognitive networks were involved and accounted for 97.4% of the variation in reading ability (R2 = 0.974, p = 0.022). Overall, networks composing the future-reading network are highly involved in processing narratives along development; however, networks related to semantic, phonological, and syntactic processing predict reading ability earlier in life, and more complex networks predict reading proficiency later in life.

Executive functions-based reading training engages the cingulo-opercular and dorsal attention networks

The aim of this study was to determine the effect of a computerized executive functions (EFs)-based reading intervention on neural circuits supporting EFs and visual attention. Seed-to-voxel functional connectivity analysis was conducted focusing on large-scale attention system brain networks, during an fMRI reading fluency task. Participants were 8- to 12-year-old English-speaking children with dyslexia (n = 43) and typical readers (n = 36) trained on an EFs-based reading training (n = 40) versus math training (n = 39). Training duration was 8 weeks. After the EFs-based reading intervention, children with dyslexia improved their scores in reading rate and visual attention (compared to math intervention). Neurobiologically, children with dyslexia displayed an increase in functional connectivity strength after the intervention between the cingulo-opercular network and occipital and precentral regions. Noteworthy, the functional connectivity indices between these brain regions showed a positive correlation with speed of processing and visual attention scores in both pretest and posttest. The results suggest that reading improvement following an EFs-based reading intervention involves neuroplastic connectivity changes in brain areas related to EFs and primary visual processing in children with dyslexia. Our results highlight the need for training underlying cognitive abilities supporting reading, such as EFs and visual attention, in order to enhance reading abilities in dyslexia.

Fluent contextual reading is associated with greater synchronization of the visual and auditory networks, fluent reading and better speed of processing in children with dyslexia

The asynchrony theory of dyslexia postulates weaker visual (orthographical processing) and auditory (phonological processing) network synchrony in dyslexic readers. The weaker visual-auditory network synchronization is suggested to contribute to slow processing speed, which supports cognitive control, contributing to single-word reading difficulty and lower reading fluency. The current study aims to determine the neurobiological signature for this theory and to examine if prompting enhanced reading speed through deleted text is associated with a greater synchronization of functional connectivity of the visual and auditory networks in children with dyslexia and typical readers (TRs). We further aimed to determine if the change in visual-auditory connectivity prompted by deleted text is associated with reading fluency and processing speed abilities. Nineteen children with dyslexia and 21 typical readers ages 8-12 years old participated in a fMRI under two types of reading conditions: a still text condition and deleted text condition, in which letters was sequentially deleted from the screen. Effects of diagnostic group and condition on functional connectivity (FC) of visual and auditory networks were examined. Results revealed a significant overall effect of condition with a marginally significant Group × Condition interaction, such that as compared with TRs, children with dyslexia showed a significantly greater increase in visual-auditory FC between the still and deleted text conditions. Additionally, for children with dyslexia, this FC increase was significantly correlated with better reading fluency and verbal/nonverbal processing speed. These results support a relationship between the synchronization of the visual and auditory networks, fluent reading and increased speed of processing abilities in children with dyslexia, which can help guide fluency-based intervention strategies.

Executive functions abilities in preschool-age children are negatively related to parental EF, screen-time and positively related to home literacy environment: an EEG study

Environmental factors such as Home Literacy Environment (HLE), screen time, and parental executive functions (EF) may influence the development of the child's EF. The purpose of this study was to determine the effect of these factors on behavioral and neurobiological measures of EF in 4-year-old children. Electroencephalogram (EEG) data were collected while children performed the Attention Network Task (ANT), showing a smaller difference between incongruent and congruent conditions is related to better EF abilities. Data were analyzed using an Event-Related Potential (ERP) technique focusing on the N200 and P300 components (reflecting executive control and orienting attention, respectively). N200 and P300 differences (delta) between amplitudes and latencies for the incongruent and congruent conditions were computed and correlated with child EF skills, HLE, screen exposure, and parental EF. Screen exposure was associated with lower EF in children and their parents. Additionally, smaller differences between N200 amplitudes and latencies for the incongruent vs. congruent conditions were associated with higher HLE scores. In contrast, greater differences between P300 amplitudes and latencies were related to longer screen time. HLE was positively associated with EF's neurobiological (EEG) and behavioral measures, and screen time was negatively associated with these measures. This study also highlights the important relationship between parental EF (i.e., family predisposition) and EF's neurobiological and behavioral measures in their children.

Altered white matter organization and its correlations with executive functioning among adolescents with epilepsy

Deficits in executive functions (EF) are a common comorbidity among adolescents with epilepsy. EF deficits were previously correlated with altered connectivity of the fronto-parietal and cingulo-opercular neural networks. The current study investigated white matter integrity in adolescents with epilepsy (n = 29) relative to healthy controls (n = 19). Participants completed questionnaires, neuropsychological testing, and brain magnetic resonance imaging (MRI) that included diffusion tensor imaging (DTI) sequences. On BRIEF parent-report questionnaires, adolescents with epilepsy demonstrated lower working memory and planning abilities than healthy controls. Among adolescents with epilepsy, DTI measurements revealed lower fractional anisotropy (FA) within the right superior longitudinal fasciculus, forceps minor, and the superior frontal segment of the corpus callosum, and higher FA in the left uncinate fasciculus, compared to healthy controls. Better working memory ability in the epilepsy group was associated with higher FA in the superior frontal segment of the corpus callosum. Only in healthy controls, working memory and planning were positively associated with FA values in the left UF, forceps minor and the superior frontal segment of the corpus callosum. The current study complements previous functional studies on the same cohort and suggests that EF impairments among adolescents with epilepsy may be related to the altered anatomical organization of white matter tracts. Combining structural and functional data could potentially enrich the neuropsychological assessment of executive functioning in adolescents with epilepsy.

Maternal education as an environmental factor related to reading in children with reading difficulties: A functional magnetic resonance imaging study

The expanded simple view of reading (SVR) model suggests that word decoding, language comprehension and executive functions are necessary for reading comprehension. Children with reading difficulties (RDs) often have deficits in critical components of reading established in the expanded SVR model and alterations in brain function of reading-related regions. Maternal education could provide children with advantageous educational opportunities or resources that support reading acquisition. The primary goal of this study was to examine the contributions of maternal education to the behavioural and neurobiological correlates of the expanded SVR model. Seventy-two 8- to 12-year-old children with RDs and typical readers (TRs) completed reading, behavioural and an functional magnetic resonance imaging stories-listening task to determine the functional connectivity of the receptive language network to the whole brain in association with maternal education. Higher maternal education was associated with better vocabulary in children with RDs and positive functional connectivity between the receptive language network and regions related to visual processing in children with RDs versus TRs. These data suggest that maternal education supports the ability to comprehend oral language and engagement of neural networks that support imagination/visualization in children with RDs.

[Formula: see text] Higher access to screens is related to decreased functional connectivity between neural networks associated with basic attention skills and cognitive control in children

Screen-based media has become a prevailing part of children's lives. Different technologies provide limitless access to a wide range of content. This accessibility has immensely increased screen exposure among children, showing that this exposure is associated with decreased cognitive abilities. This study was designed to evaluate how the neurobiological correlates for different sub-components of screen exposure, such as level of access, content, and frequency, are related to different cognitive abilities. Resting-state functional MRI data were collected in 29 native English-speaking children (8-12 years old), in addition to cognitive-behavioral measures. Functional connectivity measures within and between several networks related to cognitive control and attention were calculated [fronto-parietal (FP), cingulo-opercular (CO), dorsal attention (DAN), ventral attention (VAN), salience, default mode (DMN), cerebellar networks]. Sub-components of screen exposure were measured using the Screen-Q questionnaire. Higher access to screens was related to lower functional connectivity between neural networks associated with basic attention skills and cognitive control (i.e., DAN and salience). In addition, higher levels of parent-child interaction during screen exposure were related to increased functional connectivity between networks related to cognitive control and learning (i.e., CO and cerebellar). These findings suggest that screen exposure may reduce the engagement of basic attention and modulation of cognitive control networks and that higher levels of parent-child interaction engage cognitive control networks. An enhanced understanding of these processes can provide an important scientific basis for future educational and medical approaches regarding screen exposure.

Structural white matter characteristics for working memory and switching/inhibition in children with reading difficulties: The role of the left superior longitudinal fasciculus

Reading difficulties (RDs) are characterized by slow and inaccurate reading as well as additional challenges in cognitive control (i.e., executive functions, especially in working memory, inhibition, and visual attention). Despite evidence demonstrating differences in these readers' language and visual processing abilities, white matter differences associated with executive functions (EFs) difficulties in children with RDs are scarce. Structural correlates for reading and EFs in 8- to 12-year-old children with RDs versus typical readers (TRs) were examined using diffusion tensor imaging (DTI) data. Results suggest that children with RDs showed significantly lower reading and EF abilities versus TRs. Lower fractional anisotropy (FA) in left temporo-parietal tracts was found in children with RDs, who also showed positive correlations between reading and working memory and switching/inhibition scores and FA in the left superior longitudinal fasciculus (SLF). FA in the left SLF predicted working memory performance mediated by reading ability in children with RDs but not TRs. Our findings support alterations in white matter tracts related to working memory, switching/inhibition, and overall EF challenges in children with RDs and the linkage between working memory difficulties and FA alterations in the left SLF in children with RDs via reading.

Stroop performance is related to reading profiles in Hebrew-speaking individuals with dyslexia and typical readers

There is a debate in the literature regarding the level of contribution of executive functions (EF) to reading comprehension (RC), in the context of the simple view of reading (SVR) model. The current study aims to create sub-profiles of reading and cognitive abilities based on a measure traditionally used for evaluating EF, that is, the Stroop task, and specifically, Stroop time. Ninety-seven adults with and without reading difficulties performed reading and cognitive tasks, including the Stroop tests. Four groups were created based on Stroop performance time and a reading profile was created for each group. A mediation analysis was conducted to determine if reading accuracy and linguistic abilities predict RC mediated by Stroop time. Participants with a shorter Stroop time demonstrated better reading abilities, whereas those with longer Stroop time showed decreased reading performance. Stroop time was also negatively associated with better performance in additional cognitive abilities. A mediation analysis suggested that decoding ability and linguistic ability predict RC through EF. Our findings support the SVR model and the involvement of EF in reading proficiency and might be used for designing EF-based interventions for reading and RC difficulties.

The role of visual attention in dyslexia: Behavioral and neurobiological evidence

Poor phonological processing has typically been considered the main cause of dyslexia. However, visuo‐attentional processing abnormalities have been described as well. The goal of the present study was to determine the involvement of visual attention during fluent reading in children with dyslexia and typical readers. Here, 75 children (8–12 years old; 36 typical readers, 39 children with dyslexia) completed cognitive and reading assessments. Neuroimaging data were acquired while children performed a fluent reading task with (a) a condition where the text remained on the screen (Still) versus (b) a condition in which the letters were being deleted (Deleted). Cognitive assessment data analysis revealed that visual attention, executive functions, and phonological awareness significantly contributed to reading comprehension in both groups. A seed‐to‐voxel functional connectivity analysis was performed on the fluency functional magnetic resonance imaging task. Typical readers showed greater functional connectivity between the dorsal attention network and the left angular gyrus while performing the Still and Deleted reading tasks versus children with dyslexia. Higher connectivity values were associated with higher reading comprehension. The control group showed increased functional connectivity between the ventral attention network and the fronto‐parietal network during the Deleted text condition (compared with the Still condition). Children with dyslexia did not display this pattern. The results suggest that the synchronized activity of executive, visual attention, and reading‐related networks is a pattern of functional integration which children with dyslexia fail to achieve. The present evidence points toward a critical role of visual attention in dyslexia.

Barriers to cardiac rehabilitation: a first national survey

Introduction

Cardiovascular diseases (CVD) are among the leading causes of morbidity and mortality worldwide. Over three quarters of the cardiovascular deaths take place in low-and middle-income countries. CVD represent half of all death in the country. Despite the benefits and clinical recommendations from ESC/AHA and WHO, Cardiac Rehabilitation (CR) is still not routinely and not universally available. Numerous studies have found that barriers to access to CR are correlated with providers, patients and environment characteristics.

Purpose

This first national survey on CR assesses and identifies what the main barriers to access to CR are. In addition, this study provides suggestions for the implementation of CR in the country. This study takes into consideration the recommendations of cardiologists and cardiac surgeons for further expansion of CR practice. Until 2018, no local comprehensive CR program had been realised. Nevertheless, secondary cardiovascular preventive programs such as CR are not a priority.

Methods

A quantitative cross-sectional study design was adopted using a structured, self-administrated questionnaire. The survey was conducted in December 2018 among cardiologists and cardiac surgeons. A 25item questionnaire was used to collect information on CR. Responses were analysed using descriptive statistics SPSS software (version 24).

Results

The respondents' rate was 41.5% (n=83). 77.7% of Physicians will face barriers to refer patients to a CR program. The top 3 barriers are: first “the lack of specialist”, second barrier to overcome is “the lack of patient motivation” and third “financial covering of CR”. Supplementary learning about the benefits of CR is highly recommended to enrol more patients with CVD. CR need to be covered by a insurances and government policies above all during this time of pandemic.

Conclusions

The role of physicians in promoting patient enrolment should be optimised and exploited in the country. The access barriers identified can help to develop CR programs and to improve CR referral and enrolment rates. Funds from private parties and a budget from the government are needed to launch new CR programs in the country. Further research is needed.

Funding Acknowledgement

Type of funding sources: None.

Two-year incidence of PPMI post SAVR, modified SAVR and TAVR

Background

Moderate and high risk patients presenting with aortic stenosis are offered surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR) as therapeutic options. However, both techniques are associated with postoperative conduction abnormalities necessitating permanent pace maker implantation (PPMI).

Many factors have been implicated in increasing the risk of atrioventricular (AV) block and subsequent PPMI. The stress on the conduction system seems to be a major cause of this complication.

Methods

We conducted a study to compare the incidence of PPMI between two groups of patients. In group A, 62 patients underwent the classic SAVR and in group B, 92 patients underwent a simple modified SAVR technique (3–4 pledgeted ethibond sutures were placed above the annulus, at the commissure between the right and non coronary sinuses) that aims to decrease the mechanical trauma to the conduction system.

Results

The results revealed a significant lower PPMI rate in group B as compared to group A,at thirty days (2.17% versus 14.5%) as well as at two years (2.17% versus 17.7%) postoperatively. The statistical analysis showed that the operative technique was a strong predictor of the need for PPMI. The odds of needing pace maker implantation was significantly lower in the group of patients who underwent the simple modified SAVR technique. Of note is that the reported incidence of PPMI in the literature, at thirty days and two- years post classic SAVR were 6.1% and 11%. In addition, the rate observed in group B, was lower than the post-TAVR incidence of PPMI (9.3% at thirty days and 13% at two years post procedure), as reported by numerous studies, whether self expandable or balloon expandable valves were used.

Conclusion

This reproducible and reliable simple technique should be recommended whenever SAVR is performed.On the other hand,the low incidence of PPMI (2.17%) observed after a modified SAVR technique should be adopted as a benchmark whenever TAVR is offered as a therapeutic option. Moreover, this less traumatic procedure may be taken into consideration whenever stent design modifications for TAVR are considered.

Funding Acknowledgement

Type of funding sources: None.

Higher rates of COVID-19 but less severe infections reported for patients on Dupilumab: a Big Data analysis of the World Health Organization VigiBase

OBJECTIVE

Dupilumab (Dupixent®) is a monoclonal antibody that inhibits IL-4 and IL-13 signaling used for the treatment of allergic diseases. Whilst biologic therapy is traditionally regarded as immunosuppressive and capable to increase the infectious risk, Dupilumab does not display these characteristics and may be even protective in certain cases. We investigated the link between Dupilumab therapy and SARS-CoV-2 infection.

MATERIALS AND METHODS

We carried out a comprehensive data mining and disproportionality analysis of the WHO global pharmacovigilance database. One asymptomatic COVID-19 case, 106 cases of symptomatic COVID-19, and 2 cases of severe COVID-19 pneumonia were found.

RESULTS

Dupilumab treated patients were at higher risk of COVID-19 (with an IC0.25 of 3.05), even though infections were less severe (IC0.25 of -1.71). The risk of developing COVID-19 was significant both among males and females (with an IC0.25 of 0.24 and 0.58, respectively). The risk of developing COVID-19 was significant in the age-group of 45-64 years (with an IC0.25 of 0.17).

CONCLUSIONS

Dupilumab use seems to reduce COVID-19 related severity. Further studies are needed to better understand the immunological mechanisms and clinical implications of these findings. Remarkably, the heterogenous nature of the reports and the database structure did not allow to establish a cause-effect link, but only an epidemiologically decreased risk in the patients subset treated with dupilumab.

Higher maternal education is related to negative functional connectivity between attention system networks and reading-related regions in children with reading difficulties compared to typical readers

Ten to 15% of school-age children have reading difficulties (RD, or dyslexia), defined by deficits in phonological processing, fluency, and executive functions (EFs). Although RD is referred to as a genetic disorder, reading ability may also be affected by environmental factors such as inadequate exposure to literacy and a lack of parental involvement. These environmental components are a part of the socioeconomic status (SES) measure, which is defined by parental occupation, educational attainment, and household income and are positively correlated to reading ability. The goal of the current study was to relate maternal education, a construct of SES to executive functions (EFs) that relate to reading in children with RD compared to typical readers (TRs) using behavioral and neurobiological resting-state fMRI data. The results show that higher maternal education is negatively correlated to inhibitory control for TRs and not for children with RD. Higher maternal education was also associated with negative functional connectivity of the frontal-parietal network to the left central opercular cortex and left occipital gyrus for children with RD compared to TRs. These results suggest that higher maternal education has contrasting roles on the behavioral and neurobiological correlates of EFs for children with RD compared to TRs. We conclude that higher education levels for mothers may provide their children with a structured environment and educational resources that may assist their children with RD and TRs with cognitive development based on their reading profile.

Neuro-Behavioral Correlates of Executive Dysfunctions in Dyslexia Over Development From Childhood to Adulthood

Dyslexia is a neurobiological learning disability in the reading domain that has symptoms in early childhood and persists throughout life. Individuals with dyslexia experience difficulties in academia and cognitive and emotional challenges that can affect wellbeing. Early intervention is critical to minimize the long-term difficulties of these individuals. However, the behavioral and neural correlates which predict dyslexia are challenging to depict before reading is acquired. One of the precursors for language and reading acquisition is executive functions (EF). The present review aims to highlight the current atypicality found in individuals with dyslexia in the domain of EF using behavioral measures, brain mapping, functional connectivity, and diffusion tensor imaging along development. Individuals with dyslexia show EF abnormalities in both behavioral and neurobiological domains, starting in early childhood that persist into adulthood. EF impairment precedes reading disability, therefore adding an EF assessment to the neuropsychological testing is recommended for early intervention. EF training should also be considered for the most comprehensive outcomes.

Maternal depression is associated with decreased functional connectivity within semantics and phonology networks in preschool children

INTRODUCTION

Maternal depression is characterized by a lack of emotional responsiveness and engagement with their child, which may lead to the child's decreased cognitive, and language outcomes all related to the child's future reading outcomes. The relations between maternal depression and functional connectivity in neural circuits supporting language in the child was explored.

METHODS

Eleven 4-year-old girls completed language abilities assessment and resting-state functional magnetic resonance imaging scan. Their mothers completed the Beck's Depression Inventory (BDI) to examine maternal depression when the child was 12 months old and at the age of 4. Functional connections within the child's resting-state phonology, semantics, language networks were correlated with maternal BDI scores at the age of 4 years.

RESULTS

Higher maternal depression was associated with the child's decreased within the semantic and phonological networks connectivity during rest. Higher maternal depression at 4 years moderated the relationship between early depression scores and functional connectivity within the phonological network.

CONCLUSIONS

Maternal depression in the first year of life is related to functional connections of phonological processing and enhanced by current maternal depression levels. We conclude that after a mother gives birth, resources should be provided to minimize depressive symptoms and interventions should be applied to support their child's language development for future reading acquisition.

Current recommendations for clinical surveillance and genetic testing in rhabdoid tumor predisposition: a report from the SIOPE Host Genome Working Group

The rhabdoid tumor (RT) predisposition syndromes 1 and 2 (RTPS1 and 2) are rare genetic conditions rendering young children vulnerable to an increased risk of RT, malignant neoplasms affecting the kidney, miscellaneous soft-part tissues, the liver and the central nervous system (Atypical Teratoid Rhabdoid Tumors, ATRT). Both, RTPS1&2 are due to pathogenic variants (PV) in genes encoding constituents of the BAF chromatin remodeling complex, i.e. SMARCB1 (RTPS1) and SMARCA4 (RTPS2). In contrast to other genetic disorders related to PVs in SMARCB1 and SMARCA4 such as Coffin-Siris Syndrome, RTPS1&2 are characterized by a predominance of truncating PVs, terminating transcription thus explaining a specific cancer risk. The penetrance of RTPS1 early in life is high and associated with a poor survival. However, few unaffected carriers may be encountered. Beyond RT, the tumor spectrum may be larger than initially suspected, and cancer surveillance offered to unaffected carriers (siblings or parents) and long-term survivors of RT is still a matter of discussion. RTPS2 exposes female carriers to an ill-defined risk of small cell carcinoma of the ovaries, hypercalcemic type (SCCOHT), which may appear in prepubertal females. RT surveillance protocols for these rare families have not been established. To address unresolved issues in the care of individuals with RTPS and to propose appropriate surveillance guidelines in childhood, the SIOPe Host Genome working group invited pediatric oncologists and geneticists to contribute to an expert meeting. The current manuscript summarizes conclusions of the panel discussion, including consented statements as well as non-evidence-based proposals for validation in the future.

Children Use Regions in the Visual Processing and Executive Function Networks during a Subsequent Memory Reading Task

Memory encoding is a critical process for memory function, which is foundational for cognitive functioning including reading, and has been extensively studied using subsequent memory tasks. Research in adults using such tasks indicates the participation of visual and cognitive-control systems in remembered versus forgotten words. However, given the known developmental trajectories of these systems, the functional neuroanatomy of memory encoding in children may be different than in adults. We examined brain activation for silent word reading and checkerboard viewing during an event-related reading task in 8-12 year-old children. Results indicate greater activation for checkerboard viewing than lexical processing in early visual regions, as well as for lexical processing versus checkerboard viewing in regions in left sensorimotor mouth, cingulo-opercular and dorsal-attention networks. Greater activation for remembered than forgotten words was observed in bilateral visual system and left lateralized regions within the ventral- and dorsal-attention, cingulo-opercular and fronto-parietal networks. These findings suggest a relatively mature reliance on the cognitive-control system, but greater reliance on the visual system in children when viewing words subsequently remembered. The location of regions with greater activity for remembered words reinforces the involvement of the attention and cognitive-control systems in subsequent memory in reading.

Children with dyslexia utilize both top-down and bottom-up networks equally in contextual and isolated word reading

INTRODUCTION

Executive functions (EF) include cognitive processes that support learning and reading. Children with dyslexia experience challenges with both reading and reading comprehension. The neurobiological support for EF deficits during reading comprehension, however, has yet to be defined. Here we aimed to identify the neural networks related to EF during a reading comprehension task focusing on top-down and bottom-up networks in children with dyslexia and typical readers (TR).

METHOD

Twenty children with dyslexia and 19 TR aged 8-12 were scanned during a sentence comprehension (SC) task that included isolated words and sentences that make sense, in addition to undergoing reading and EF behavioral assessment. Functional connectivity within and between four EF networks related to top-down and bottom-up processing were calculated.

RESULTS

Children with dyslexia scored significantly lower in reading and EF testing in several subdomains compared to TR. Children with dyslexia displayed decreased accuracy in both task conditions compared to TR during the SC task. Neuroimaging data analysis revealed that TR had greater functional connectivity within and between top-down and bottom-up processes, in the sentence vs. isolated word condition, compared to children with dyslexia.

DISCUSSION

TR demonstrate a reliance on top-down and bottom-up networks only during sentence comprehension. In children with dyslexia, however, this reliance was not found in either of the task conditions, suggesting that both conditions were equally challenging for them. These findings emphasize the involvement of EF networks in the reading comprehension process and highlight their impaired functionality among children with reading difficulties.

Stroke symptoms impact on mental and physical health: A Lebanese population based study

BACKGROUND/OBJECTIVE

Stroke symptoms in the absence of diagnosed stroke are common worldwide and associated with stroke risk factors and great impact on the physical and mental health functioning. The aim of this study was to assess, at the national level, the association of stroke symptoms with mental and physical health.

METHODS

Quality of life was assessed using physical and mental component summary scores (PCS and MCS) of the Short Form 12v2 Health Survey in the Lebanese population. We assessed the differences in the mean PCS and MCS scores among asymptomatic individuals with no stroke/transient ischemic attack (TIA) history (n=1167), symptomatic individuals with no stroke/TIA history (n=125) and those with stroke/TIA history (n=46). Psychometric properties of the Lebanese version of the SF- 12v2 were evaluated using principal component analysis.

RESULTS

Symptomatic individuals had an average PCS scores of 2.31 (95%CI: 0.75-3.88) points lower and those with stroke/TIA history had 3.26 (95%CI: 1.01-5.51) points lower when compared with asymptomatic individuals with no stroke/TIA history. Similarly, MCS scores for symptomatic individuals were 2.58 (95%CI: 1.02-4.13) points lower and those with stroke/TIA history had 3.28 (95%CI: 1.06-5.50) points lower than asymptomatic individuals.

CONCLUSION

Physical and mental health functioning declined among symptomatic individuals and those with stroke/TIA history. Thus, frequent monitoring for the early detection of stroke symptoms may be recommended.

Relationship Between Eye-Movement Patterns, Cognitive Load, and Reading Ability in Children with Reading Difficulties

Children with reading difficulties (RD) share challenges in executive functions (EF). Neurobiological correlates provide evidence for EF challenges during reading among these readers, but an online cognitive load detection mechanism has yet to be developed. Nevertheless, eye-movement tracking can provide online data of reading patterns (pupil dilation, fixations) and, indeed, atypical eye-movement patterns of children with RD during reading have been documented. To identify eye-movement patterns related to increased cognitive load during reading in children with RD compared to typical readers, eye movements of 8-12-year-old English-speaking children were recorded during their reading of sentences with increasing difficulty (sentences that make sense, then sentences that do not make sense) and comparing incorrect and correct responses. Children with RD demonstrated greater pupil dilation when reading sentences that make sense than when reading sentences that do not make sense and also when reading incorrectly, compared to typical readers. Increased pupil dilation in children with RD when reading sentences correctly was positively correlated with phonological awareness capabilities. Higher phonological awareness and reading abilities were related to increased pupil dilation only in children with RD during correct reading, which is related to a heavier cognitive load. Results suggest that in addition to traditional findings of altered fixation patterns in children with RD, increased pupil dilation during reading may reflect EF challenges among this population. These findings can potentially be used to adapt online written materials for children with RD based on their fixation and pupil dilation patterns.

Nonalcoholic fatty liver disease as a risk factor for Clostridium difficile-associated diarrhea

AIMS

Clostridium difficile is the most common cause of infectious nosocomial diarrhea among adults in developed countries. Nonalcoholic fatty liver disease (NAFLD) is considered the most common chronic liver disease and it is associated with bacterial infections. Our goal was to assess whether NAFLD considered a risk factor for C. difficile-associated diarrhea (CDAD).

METHODS

We conducted a retrospective study of patients admitted with CDAD at Baruch Padeh Medical Center, Poria, Israel during a period of four years. Data on demographic characteristics, clinical signs, underlying conditions, presence of fatty liver based on computed tomography/ultrasonography imaging and several risk factors for CDI were collected. The control group included patients with diarrhea who were negative for CDT and had been hospitalized during the same period. The controls were matched for age (±5 years) and gender.

RESULTS

Totally, 115/164 patients with CDAD met the inclusion criteria. The control group was consisted of 115 hospitalized patients with non-CDAD. The mean age of all the participants (230) was 69.57 ± 18 years. NAFLD was found in 76/115 (66%) patients with CDAD vs. 35/115 (30.4%) in the control group, P < 0.001. Moreover, we found significant associations between CDAD group and metabolic syndrome, prior use of antibiotic in the last 3 months, NAFLD and high serum levels of C-reactive protein. Multivariate analysis showed that NAFLD, odds ratio 1.51, 95% confidence interval 1.2-1.95, P = 0.05 was significantly associated with CDAD.

CONCLUSIONS

This retrospective study showed that NAFLD is a risk factor for CDAD. Moreover, metabolic syndrome and high serum levels of C-reactive protein were significantly associated with the risk of CDAD.

Decreased Functional Connectivity Between the Left Amygdala and Frontal Regions Interferes With Reading, Emotional, and Executive Functions in Children With Reading Difficulties

INTRODUCTION

Dyslexia is a reading disorder characterized by significant difficulty in reading, as well as reports of altered executive functions (EF). Children with reading difficulties (RD) experience a broad range of social and emotional problems. Recently it was suggested that children with RD have altered functional connections within the amygdala, which is related to emotional processing. Altered brain laterality related to reading was previously reported in children with RD. Hence, we sought to determine the differences in functional connectivity between the right and left emotional network as related to emotional challenges and the other reported difficulties in reading and EF in children with RD compared to typical readers.

METHODS

Sixty-four 8 to 12 year old children, 27 children with RD and 37 age-matched typical readers, participated in the study. Reading, emotional, and EF abilities were assessed. Global efficiency of the emotional network was calculated and compared between the groups, and left vs. right functional connectivity of the amygdala was tested using the CONN toolbox. Functional connectivity measures were then associated with measures of reading, emotional, and EF abilities.

RESULTS

Children with RD showed significantly decreased emotional and EF abilities compared to typical readers. A negative correlation between reading, emotional, and EF abilities was determined in both groups. Neuroimaging results showed decreased global efficiency measures within the emotional network in children with RD, who also showed lower functional connectivity between the amygdala and the left and right frontal pole regions. Results also indicated increased functional connectivity of the right vs. left amygdala with left and right pre-central and post-central gyri regions, which were related to decreased reading, emotional, and EF abilities in both typical readers and children with RD.

CONCLUSION

The positive relationship between EF and emotional abilities in children with RD strengthens the relationship between EF difficulties and emotional stress, which in turn may lower EF abilities (monitoring, inhibition, and attention) as well as decreased reading abilities. The emotional challenges in children with RD were associated with decreased functional connectivity of the left amygdala with pre/post central gyrus and cognitive-control regions. These findings suggest that although the right hemisphere is thought to be related to emotional stress, it was the decreased control of the left hemisphere that was related to emotional disturbance in children with RD.

Maternal depression is associated with altered functional connectivity between neural circuits related to visual, auditory, and cognitive processing during stories listening in preschoolers

BACKGROUND

Maternal depression can influence the early activity of a mother reading stories to a young child, as depressed mothers are less likely to read to their children. Here, maternal depression association to neurobiological circuitry of narrative comprehension, visualization, and executive functions during stories listening was examined in 21 4-year-old girls and their mothers. Maternal depression scores were collected from the mothers, and functional MRI during stories listening was collected from the children.

RESULTS

Increased maternal depression was related to decreased functional connectivity between visualization and auditory regions and increased connectivity between the right visual cortex and dorsolateral prefrontal cortex in the children.

CONCLUSIONS

This study highlights the need to monitor maternal depression and provide interventions to ensure positive linguistic outcomes in children.

Greater functional connectivity within the cingulo-opercular and ventral attention networks is related to better fluent reading: A resting-state functional connectivity study

Executive functions are higher-order cognitive abilities that affect many of our daily actions, including reading. A two-system model for cognitive control comprises a bottom-up system composed of the dorsal and ventral attention networks and a more evolved top-down system involving the frontoparietal and cingulo-opercular networks. We examined both within- and between-network functional connectivity of these four networks in 26 8-12-year-old children with readong difficulties and 30 age-matched typical readers using resting-state functional MRI. Fluency and nonfluency behavioral reading measures were collected, and the scores were analyzed together with the functional data. Children with reading difficulties did not differ in functional connectivity for the four networks compared to typical readers. Grouping the entire cohort into low vs. high fluency-level reading groups, however, revealed significantly higher functional connectivity values within the cingulo-opercular and ventral attention cognitive-control networks for the high fluency group. Higher functional connectivity Trends between the cognitive-control networks were also observed in the high fluency group compared to the low fluency group. A similar analysis using a nonfluency word-reading task grouping did not uncover differences between the two groups. The results emphasize the complexity of the fluency task, as a test that relies on cognitive-control abilities, at both the bottom-up and top-down levels. Therefore, it may be posited that the fluency task may also be a challenge for typical readers despite their intact performance. The results reinforce the relationship between fluent reading and functional connectivity of the cognitive-control networks, emphasizing the various cognitive-control abilities that underlie this complex reading ability.

Hyperconnectivity during screen-based stories listening is associated with lower narrative comprehension in preschool children exposed to screens vs dialogic reading: An EEG study

OBJECTIVES

Dialogic reading (DR) is a shared storybook reading intervention previously shown to have a positive effect on both literacy and general language skills. The aim of this study was to examine the effect of DR compared to screen-based intervention on electrophysiological markers supporting narrative comprehension using EEG.

METHODS

Thirty-two typically developing preschoolers, ages 4 to 6 years, were assigned to one of two intervention groups: Dialogic Reading Group (DRG, n = 16) or Screen Story Group (SSG, n = 16). We examined the effect of intervention type using behavioral assessment and a narrative comprehension task with EEG.

RESULTS

The DRG showed improved vocabulary and decreased functional connectivity during the stories-listening task, whereas the SSG group showed no changes in vocabulary or connectivity. Significantly decreased network strength and transitivity and increased network efficiency were observed in the DRG following intervention. Greater network strength and transitivity at follow-up were correlated with increased vocabulary.

CONCLUSIONS

The results suggest the beneficial effect of DR in preschool-age children on vocabulary and EEG-bands related to attention in the ventral stream during narrative comprehension. Decreased functional connectivity may serve as a marker for language gains following reading intervention.

SIGNIFICANCE

DR intervention for preschool-age children may reduce interfering connections related to attention, which is related to better narrative comprehension.

Screen-exposure and altered brain activation related to attention in preschool children: An EEG study

Exposure to screens has been shown to reduce attention span in children. Increased slow-wave (theta band) and decreased fast-wave (beta and gamma bands) generated from EEG, as well as increased theta/beta ratio, have been observed in children with Attention-Deficit-Hyperactivity-Disorder (ADHD). This study examined the relationship between 6-weeks screen exposure and attention abilities in typically developing preschoolers using EEG during rest. Theta and beta bands were compared, and visual attention and parental reports for attention abilities were controlled. Results suggested that the active control group showed improved visual-attention abilities following the exposure to stories, whereas the screen group did not show improved visual attention. EEG results suggested a higher connectivity in theta vs. beta bands in the screen group, but not in the control group. Results support the negative relationship between screen exposure and attention-related patterns generated from EEG in typically developing preschool children.

Dialogic reading vs screen exposure intervention is related to increased cognitive control in preschool-age children

AIM

Shared reading leads to better language and executive functions. This study was designed to examine the effect of dialogic reading compared to screen-exposed intervention on executive functions using behavioural and electroencephalogram measures.

METHODS

The effect of six weeks of dialogic reading intervention on executive functions was examined in 16 children (seven females, 61.73 months, SD 7.07, min-max 50-170) vs 16 children exposed to screen (six females, 64.31 months, SD 64.31, min-max 52-74) recruited through posted ads in daycares in the north of Israel. Behavioural and attention/inhibition electroencephalogram tasks were used to assess the effects of intervention.

RESULTS

Comparisons using t-test showed that the dialogic reading group demonstrated higher executive functions and language scores vs the screen-exposed group. Greater accuracy rates, shorter reaction times and a smaller gap between P300 amplitudes were found for the dialogic reading group compared to the screen group for the electroencephalogram task.

CONCLUSION

Dialogic reading intervention is related to improved executive functions and language abilities compared to screen-based story-telling. Parents and teachers should consider employing this method in preschool children as a facilitator for future academic abilities.

Altered Functional Connectivity of the Executive Functions Network During a Stroop Task in Children with Reading Difficulties

Children with reading difficulties (RDs) often receive related accommodations in schools, such as additional time for examinations and reading aloud written material. Existing data suggest that these readers share challenges in executive functions (EFs). Our study was designed to determine whether children with RDs have specific challenges in EFs and define neurobiological signatures for such difficulties using magnetic resonance imaging (MRI) data. Reading and EFs abilities were assessed in 8-12-year-old children with RDs and age-matched typical readers. Functional MRI data were acquired during a Stroop task, and functional connectivity of the EFs defined network was calculated in both groups and related to reading ability. Children with RDs showed lower reading and EFs abilities and demonstrated greater functional connectivity between the EFs network and visual, language, and cognitive control regions during the Stroop task, compared to typical readers. Our results suggest that children with RDs utilize neural circuits supporting EFs more so than do typical readers to perform a cognitive task. These results also provide a neurobiological explanation for the challenges in EFs shared by children with RDs and explain challenges this group shares outside of the reading domain.

Increased Functional Connectivity Within and Between Cognitive-Control Networks from Early Infancy to Nine Years During Story Listening

The cingulo-opercular (CO) and frontoparietal (FP) networks are part of the cognitive-control system of the brain. Evidence suggests that over the course of development, brain regions supporting cognitive-control functions become more integrated within their networks (i.e., have increased within-network connectivity), more separated from other networks, and, due to increased maturation along development, are more functionally connected between the networks. The focus of this study was to characterize the developmental trajectory of the CO and FP networks from early infancy (17 months) to 9 years of age in typically developing children while listening to stories, using functional connectivity analyses. Seventy-four children underwent a functional magnetic resonance imaging session while listening to stories inside the scanner. Within- and between-network functional connectivity and graph theory measures were compared during development. Developmental increase in functional connectivity within the CO network and between the CO and FP networks, as well as global efficiency of the CO network from 17 months to 9 years of age, was observed. These findings highlight the involvement of the CO and FP networks in story listening from early infancy, which increases along development. Future studies examining failures in language acquisition to further explore the role of these networks in story listening are warranted.

Decreased functional connectivity of the salience network during narrative comprehension in children with reading difficulties: An fMRI study

Dyslexia is a neurobiological learning disability, reflected through deficits in written (i.e. reading) but not in spoken language. Since written and spoken language rely on cognitive control abilities, we aimed to compare functional connectivity of the understudied salience network which is related to cognitive control in children with dyslexia vs. typical readers during a functional MRI narrative comprehension task. Although children with dyslexia showed similar comprehension levels as typical readers, neuroimaging data revealed children with dyslexia showed significantly decreased functional connectivity values of an independent component (IC) related to the salience network. The functional connectivity values in the salience network IC were negatively correlated with behavioral data of working memory in those with dyslexia. These findings further express that dyslexia is manifested through atypical involvement of neural circuits related to EF, specifically the salience network even when attending narratives. Since the salience network is related to switching abilities and error detection, future research should focus on strengthening these abilities early in life for better future reading outcomes.

•

Behavioral data supports executive functioning and reading deficiencies in dyslexia

•

Significant greater functional connectivity in the salience network IC in typical readers vs children with dyslexia

•

Negative correlation between functional connectivity of the salience network, working memory abilities and processing speed

The Involvement of Speed-of-Processing in Story Listening in Preschool Children: A Functional and Structural Connectivity Study

Story listening in children relies on brain regions supporting speech perception, auditory word recognition, syntax, semantics, and discourse abilities, along with the ability to attend and process information (part of executive functions). Speed-of-processing is an early-developed executive function. We used functional and structural magnetic resonance imaging (MRI) to demonstrate the relationship between story listening and speed-of-processing in preschool-age children. Eighteen participants performed story-listening tasks during MRI scans. Functional and structural connectivity analysis was performed using the speed-of-processing scores as regressors. Activation in the superior frontal gyrus during story listening positively correlated with speed-of-processing scores. This region was functionally connected with the superior temporal gyrus, insula, and hippocampus. Fractional anisotropy in the inferior frontooccipital fasciculus, which connects the superior frontal and temporal gyri, was positively correlated with speed-of-processing scores. Our results suggest that speed-of-processing skills in preschool-age children are reflected in functional activation and connectivity during story listening and may act as a biomarker for future academic abilities.

Maturation of Brain Regions Related to the Default Mode Network during Adolescence Facilitates Narrative Comprehension

Objectives

Although the Default Mode Network (DMN) has been examined extensively in adults, developmental characteristics of this network during childhood are not fully understood.

Methods

In this longitudinal study, we characterized the developmental changes in the DMN in fifteen children who were each scanned three times during a narrative comprehension task using magnetic resonance imaging.

Results

Despite similar brain-activation patterns along developmental ages 5 to 18 years when listening to stories, increased, widely distributed deactivation of the DMN was observed in children between the ages of 11 and 18 years. Our findings suggest that changes occurring with increased age, primarily brain maturation and cognitive development drive deactivation of the DMN, which in turn might facilitate attendance to the task.

Conclusions

The interpretation of our results is as a possible reference for the typical course of deactivation of the DMN and to explain the impaired patterns in this neural network associated with different language-related pathologies.

Antioxidant Enzyme Activity and Cognition in Obese Individuals with or without Metabolic Risk Factors

Background: The metabolic syndrome may be associated with cognitive impairment and increased oxidative stress. Aim: To document the association between metabolic syndrome, cognitive impairment and oxidative stress activity in metabolically healthy obese and in metabolically unhealthy obese individuals. Methods: 60 obese individuals aged (49±10 years, 52% male) were enrolled. Obesity was defined as BMI>30. Metabolic syndrome was defined according to ATP III guidelines. Obese individuals were divided into 2 groups: Group 1, metabolically healthy obese (≤2 components of metabolic syndrome), and Group 2, metabolically unhealthy obese (>2 components of metabolic syndrome). Cognitive dysfunction was determined by Montreal cognitive assessment score. Liver Fibro scan (Elastography), Inflammation (CRP), pro oxidants (MDA), antioxidant activity (SOD, PON, GSH, GPx) and insulin resistance (HOMA-IR) were measured. Results: Of the 30 metabolically unhealthy obese individuals, 13% developed dementia, 51% had mild cognitive impairment, and 36% had a normal cognitive score. In the metabolically healthy obese group, 3% developed dementia, 7% had mild cognitive impairment, and 90% had a normal cognitive score. There was a significant difference in liver stiffness (7±3 vs. 5.2±2.7 kpa, p<0.001), liver fat measurement (337±51 vs. 280±20 db/m, p<0.001), MDA (4.7±0.9 vs. 5.47±1.12 mM, P<0.003), Glutathione GSH (27.2±2.4 vs. 28.4±2.3, P<0.03), CRP (9±6 vs. 7±6 P<0.001) and insulin resistance (2.5±1 vs. 6±5.5 p<0.02) between the 2 groups. Correlations were significant between GPx activity and liver stiffness (r=0.37), GPx activity and abdominal girth (r=-0.22) and glucose concentration and SOD activity (r=0.4). Multivariate analysis showed that HOMA-IR, MDA and GSH were the most powerful predictors of metabolically unhealthy obesity. Conclusion: There is a significant mild cognitive impairment and increased oxidative stress activity in the metabolically unhealthy obese. Whether treatment with anti-oxidants improves cognitive dysfunction remains to be determined.

Blood glucose control using a computer-guided glucose management system in allogeneic hematopoietic cell transplant recipients

Allogeneic hematopoietic cell transplantation (HCT) is a potentially curative treatment for patients with hematological malignancies. However, is associated with substantial rates of morbidity and mortality. We and others have shown that malglycemia is associated with adverse transplant outcome. Therefore, improving glycemic control may improve transplant outcome. In this prospective study we evaluated the feasibility of using Glucommander (a Computer-Guided Glucose Management System; CGGM) in order to achieve improved glucose control in hospitalized HCT patients. Nineteen adult patients contributed 21 separate instances on CGGM. Patients were on CGGM for a median of 43 h. Median initial blood glucose (BG) on CGGM was 244 mg/dL, and patients on 20 study instances reached the study BG target of 100-140 mg/dL after a median of 6 h. After BG reached the target range, the median average BG level per patient was 124 mg/dL. Six patients had a total of 10 events of BG <70 mg/dL (0.9% of BG measurements), and no patients experienced BG level <40 mg/dL. The total estimated duration of BG <70 mg/dL was 3 h (0.2% of the total CGGM time). In conclusion, our study demonstrates that stringent BG control in HCT patients using CGGM is feasible.