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Quantifying cognitive potential relies on psychometric measures that do not directly reflect cortical activity. While the relationship between cognitive ability and resting state EEG signal dynamics has been extensively studied in children with below-average cognitive performances, there remains a paucity of research focusing on individuals with normal to above-average cognitive functioning. This study aimed to elucidate the resting EEG dynamics in children aged four to 12 years across normal to above-average cognitive potential. Our findings indicate that signal complexity, as measured by Multiscale Entropy (MSE), was not significantly predictive of the level of cognitive functioning. However, utilizing Directed Phase Lag Index (DPLI) as an effective connectivity measure, we observed consistent patterns of information flow between anterior and posterior regions. Fronto-parietal as well as local connectivity patterns were seen across most of the cognitive functions. Moreover, specific connectivity patterns were obtained for each intellectual quotient index (namely verbal comprehension, visuospatial, fluid reasoning, and processing speed indexes as well as full-scale intellectual quotient). These results underscore the presence of long-range connections and support fronto-parietal theories of cognitive abilities within the resting state brain dynamics of children. [ABSTRACT FROM AUTHOR]

Objectives: To understand why some long-term childhood cancer survivors experience positive adjustment in the long run,[Q1] this study aimed to (1) explore associations between well-being, health status, social support, and emotion regulation (ER) strategies in a cohort of long-term childhood lymphoblastic leukemia (cALL) survivors, (2) identify the individual contribution of each ER strategy to well-being (3) and their interaction with social support. Methods: We used data from 92 participants from the PETALE cohort (51% female, aged 24 ± 7 years). Measures included well-being (WHO-5), health status (15D), social support (SSQ-6), cognitive reappraisal and expressive suppression (ERQ), and emotional processing and expression (EAC). We modeled the odds of high well-being adjusting for health status in logistic regressions and explored the moderating role of social support with bootstrap techniques. Independent of clinical history, high well-being was associated with better health status, higher social support, more frequent use of cognitive reappraisal and emotional processing. Results: We found a main contribution of emotional processing to well-being (OR = 2.12, 95% CI = 1.09-5.37). The interaction between low suppression and high social support was significant (OR =.40, 95% CI =.13-.79). Probabilities for high well-being were 96% when expressive suppression was low and social support was high. Results suggest approaching one's own emotions may contribute to well-being in long-term childhood cancer survivors. Clinical implications: Combining curbing emotional suppression with promoting supportive social environment could be a promising target for future supportive care interventions in survivors. [ABSTRACT FROM AUTHOR]

Introduction: Metformin has been used as a targeted treatment to potentially improve cognition and slow the typical IQ decline that occurs during development among individuals with fragile X syndrome (FXS). In this follow-up study, we are following the trajectory of IQ and adaptive behavior changes over 1 to 3 years in individuals with FXS who are clinically treated with metformin in an open label trial. Method: Individuals with FXS ages 6 to 25 years (mean 13.15 ± 5.50) and nonverbal IQ mean 57.69 (±15.46) were treated for 1-3 years (1.88 ± 0.63). They all had a baseline IQ test using the Leiter-III non-verbal cognitive assessment and the Vineland-III adaptive behavior assessment before the start of metformin. Repeat Leiter-III and Vineland-III were completed after at least 1 year of metformin (500-1,000 mg/dose given twice a day). Result: There were no significant changes in non-verbal IQ or in the adaptive behavior measurements at FDR < 0.05. The findings thus far indicate that both IQ and adaptive behavior are stable over time, and we did not see a significant decline in either measure. Conclusion: Overall, the small sample size and short follow-up duration limit the interpretation of the effects of metformin on cognitive development and adaptive functioning. There is individual variability but overall for the group there was no significant decline in IQ or adaptive behavior. [ABSTRACT FROM AUTHOR]

Simple Summary: Acute lymphoblastic leukemia (ALL) is the most common childhood cancer in North America, with a survival rate of 85%. Despite improved outcomes, many survivors experience long-term side effects, including cognitive issues. This study investigates whether a brain imaging technique called Magnetization Transfer Ratio (MTR) can detect changes in the brain's white matter of ALL survivors and if these changes are related to cognitive problems. Lower MTR levels in survivors, indicating myelin damage, correlated with cognitive impairments. Additionally, a link between MTR levels and the doses of certain chemotherapy drugs received was discovered. These findings improve our understanding of ALL survivorship and highlight the importance of MTR in monitoring brain health during and after cancer treatment. Acute lymphoblastic leukemia (ALL) stands as the most prevalent form of pediatric cancer in North America, with a current five-year survival rate of 85%. While more children achieved ALL remission and transition into adulthood, the prevalence of long-term treatment-related effects, especially neurocognitive sequelae, remains significant. This study pursues two objectives. Firstly, it investigates if Magnetization Transfer Ratio (MTR), a method assessing myelin integrity, is sensitive to white matter (WM) microstructural changes in long-term ALL survivors and whether these relate to cognitive impairments. Secondly, it examines the dose-related effects of chemotherapy agents on the MTR and its relationship to other risk factors such as female sex, early age diagnosis, and cranial radiotherapy. Magnetization transfer imaging was utilized to assess WM integrity in 35 survivors at a mean of 18.9 years after the onset of ALL (range since diagnosis: 6.9–26.8). Additionally, 21 controls matched for age, sex, and education level, with no history of cancer, were included. MTR was extracted from both the entire brain's WM and the corpus callosum through semi-automated procedures. The results indicated lower MTR means in survivors, which is linked to cognitive function. Negative associations between MTR means and intrathecal agents' (MTX, cytarabine, and hydrocortisone) cumulative doses received were highlighted. This study offers valuable insights into the connections between myelin deterioration, cognitive impairment, and the implications of IT chemotherapy, enhancing our understanding of ALL survivorship dynamics. It underscores MTR's relevance in monitoring neurotoxicity during oncological drug follow-up examinations. [ABSTRACT FROM AUTHOR]

Background: Prepartum and postpartum maternal symptoms of stress, anxiety and depression are likely to influence the child's sensory processing through hormonal alterations and an influence on mother–child interactions. Objective: We investigated the associations between maternal prepartum and postpartum symptoms of depression, anxiety and stress related to the COVID-19 pandemic and childhood sensory avoidance at 18 months. Methods: Longitudinal data from 409 participants followed during the COVID-19 pandemic were used. They completed questionnaires during pregnancy and up to 18 months after delivery. Maternal distress symptoms were assessed prenatally and at 18 months postnatally using the Edinburgh Postnatal Depression Scale, the Generalized Anxiety Disorders 7-item Scale and a 10-point scale assessing the level of stress felt related to the COVID-19 pandemic. Child sensory avoidance was assessed at 18 months postpartum using the Infant/Toddler Sensory Profile—Second Edition. Pearson correlations and multiple regressions measured the associations between maternal distress symptoms and child sensory avoidance. Results: Prepartum and 18-month postpartum maternal depression and anxiety were significantly correlated with childhood sensory avoidance (p < 0.05). Together, these variables explained 7.18% (F = 2.12, p < 0.05) of the variance of childhood sensory avoidance. Conclusions: These results support the contributory effect of prepartum and postpartum maternal distress on childhood sensory development. [ABSTRACT FROM AUTHOR]

Background: The COVID-19 pandemic has significantly affected the mental health of pregnant persons. Objective: We aimed to evaluate the impact of maternal mental health and antidepressant use on children's cognitive development. Methods: We followed a cohort of children born during the COVID-19 pandemic. Maternal mental health was self-reported during pregnancy (Edinburgh Postnatal Depression Scale, General Anxiety Disorder-7, stress levels, and antidepressant use). The child's cognitive development was measured using the third edition of the Ages & Stages Questionnaires® (ASQ-3) at 18 months. Multivariate multinomial logistic regression models were built to assess the association between in utero exposure to maternal mental health and ASQ-3 domains: communication, gross motor, fine motor, problem-solving, and personal–social. Results: Overall, 472 children were included in our analyses. After adjusting for potential confounders, a need for further assessment in communication (adjusted odds ratio (aOR) 12.2, 95% confidence interval (CI) (1.60;92.4)), and for improvement in gross motricity (aOR 6.33, 95%CI (2.06;19.4)) were associated with in utero anxiety. The need for improvement in fine motricity (aOR 4.11, 95%CI (1.00; 16.90)) was associated with antidepressant exposure. In utero depression was associated with a decrease in the need for improvement in problem solving (aOR 0.48, 95%CI (0.24; 0.98)). Conclusions: During the COVID-19 pandemic, maternal mental health appears to be associated with some aspects of children's cognitive development. [ABSTRACT FROM AUTHOR]

Late effects such as neurocognitive issues and fatigue have been reported in childhood acute lymphoblastic leukemia (cALL) survivors. Yet, their association is often poorly understood. In this study, we wished to (1) describe neurocognitive difficulties and fatigue in a well-characterized cohort of long-term cALL survivors and (2) explore the risk of having neurocognitive deficits as a function of fatigue. Childhood ALL survivors (N = 285) from three Canadian treatment centers completed the DIVERGT battery of cognitive tests and the PedsQL Multidimensional Fatigue Scale. We performed logistic regressions to assess the risk of a survivor to show cognitive deficits (<2.0 SD) depending on their fatigue levels. At least one cognitive deficit on the DIVERGT was present in 31% of participants. Domains primarily affected were working memory, fine motor skills, and verbal fluency. Sleep/rest fatigue in youths was higher than norms (d = 0.35). The risk for cognitive deficits increased independently with levels of fatigue in the domains of cognitive speed and flexibility, working memory, and verbal fluency. For every 10-point increase on general or sleep/rest fatigue on the 0-100 scale, there was a median +23–35% risk of showing a deficit among the 7 tasks significantly associated with fatigue. Fatigue may constitute a complementary target when searching to mitigate cognitive issues in this population. [ABSTRACT FROM AUTHOR]

This study contributes to a greater understanding of the utility of molecular biomarkers to identify clinical phenotypes of fragile X syndrome (FXS). Correlations of baseline clinical trial data (molecular measures—FMR1 mRNA, CYFIP1 mRNA, MMP9 and FMRP protein expression levels, nonverbal IQ, body mass index and weight, language level, NIH Toolbox, adaptive behavior rating, autism, and other mental health correlates) of 59 participants with FXS ages of 6–32 years are reported. FMR1 mRNA expression levels correlated positively with adaptive functioning levels, expressive language, and specific NIH Toolbox measures. The findings of a positive correlation of MMP-9 levels with obesity, CYFIP1 mRNA with mood and autistic symptoms, and FMR1 mRNA expression level with better cognitive, language, and adaptive functions indicate potential biomarkers for specific FXS phenotypes. These may be potential markers for future clinical trials for targeted treatments of FXS. [ABSTRACT FROM AUTHOR]

Macrocephaly has been associated with neurodevelopmental disorders; however, it has been mainly studied in the context of pathological or high-risk populations and little is known about its impact, as an isolated trait, on brain development in general population. Electroencephalographic (EEG) power spectral density (PSD) and signal complexity have shown to be sensitive to neurodevelopment and its alterations. We aimed to investigate the impact of macrocephaly, as an isolated trait, on EEG signal as measured by PSD and multiscale entropy during the first year of life. We recorded high-density EEG resting-state activity of 74 healthy full-term infants, 50 control (26 girls), and 24 macrocephalic (12 girls) aged between 3 and 11 months. We used linear regression models to assess group and age effects on EEG PSD and signal complexity. Sex and brain volume measures, obtained via a 3D transfontanellar ultrasound, were also included into the models to evaluate their contribution. Our results showed lower PSD of the low alpha (8–10 Hz) frequency band and lower complexity in the macrocephalic group compared to the control group. In addition, we found an increase in low alpha (8.5–10 Hz) PSD and in the complexity index with age. These findings suggest that macrocephaly as an isolated trait has a significant impact on brain activity during the first year of life. [ABSTRACT FROM AUTHOR]

Neurodevelopmental disorders (NDDs) are mostly diagnosed around the age of 4–5 years, which is too late considering that the brain is most susceptive to interventions during the first two years of life. Currently, diagnosis of NDDs is based on observed behaviors and symptoms, but identification of objective biomarkers would allow for earlier screening. In this longitudinal study, we investigated the relationship between repetition and change detection responses measured using an EEG oddball task during the first year of life and at two years of age, and cognitive abilities and adaptive functioning during preschool years (4 years old). Identification of early biomarkers is challenging given that there is a lot of variability in developmental courses among young infants. Therefore, the second aim of this study is to assess whether brain growth is a factor of interindividual variability that influences repetition and change detection responses. To obtain variability in brain growth beyond the normative range, infants with macrocephaly were included in our sample. Thus, 43 normocephalic children and 20 macrocephalic children were tested. Cognitive abilities at preschool age were assessed with the WPPSI-IV and adaptive functioning was measured with the ABAS-II. Time–frequency analyses were conducted on the EEG data. Results indicated that repetition and change detection responses in the first year of life predict adaptive functioning at 4 years of age, independently of head circumference. Moreover, our findings suggested that brain growth explains variability in neural responses mostly in the first years of life, so that macrocephalic children did not display repetition suppression responses, while normocephalic children did. This longitudinal study demonstrates that the first year of life is an important period for the early screening of children at risk of developing NDDs. [ABSTRACT FROM AUTHOR]

Pleiotropy occurs when a genetic variant influences more than one trait. This is a key property of the genomic architecture of psychiatric disorders and has been observed for rare and common genomic variants. It is reasonable to hypothesize that the microscale genetic overlap (pleiotropy) across psychiatric conditions and cognitive traits may lead to similar overlaps at the macroscale brain level such as large-scale brain functional networks. We took advantage of brain connectivity, measured by resting-state functional MRI to measure the effects of pleiotropy on large-scale brain networks, a putative step from genes to behaviour. We processed nine resting-state functional MRI datasets including 32 726 individuals and computed connectome-wide profiles of seven neuropsychiatric copy-number-variants, five polygenic scores, neuroticism and fluid intelligence as well as four idiopathic psychiatric conditions. Nine out of 19 pairs of conditions and traits showed significant functional connectivity correlations (r Functional connectivity), which could be explained by previously published levels of genomic (r Genetic) and transcriptomic (r Transcriptomic) correlations with moderate to high concordance: r Genetic— r Functional connectivity = 0.71 [0.40–0.87] and r Transcriptomic— r Functional connectivity = 0.83 [0.52; 0.94]. Extending this analysis to functional connectivity profiles associated with rare and common genetic risk showed that 30 out of 136 pairs of connectivity profiles were correlated above chance. These similarities between genetic risks and psychiatric disorders at the connectivity level were mainly driven by the overconnectivity of the thalamus and the somatomotor networks. Our findings suggest a substantial genetic component for shared connectivity profiles across conditions and traits, opening avenues to delineate general mechanisms—amenable to intervention—across psychiatric conditions and genetic risks. [ABSTRACT FROM AUTHOR]

Background: Mutations in the GATOR1 complex genes, DEPDC5 and NPRL3, play a major role in the development of lesional and non-lesional focal epilepsy through increased mTORC1 signalling. We aimed to assess the effects of mTORC1 hyperactivation on GABAergic inhibitory circuits, in 3 and 5 individuals carrying DEPDC5 and NPRL3 mutations respectively using a multimodal approach including transcranial magnetic stimulation (TMS), magnetic resonance spectroscopy (MRS), and electroencephalography (EEG). Results: Inhibitory functions probed by TMS and MRS showed no effect of mutations on cortical GABAergic receptor-mediated inhibition and GABA concentration, in both cortical and subcortical regions. However, stronger EEG theta oscillations and stronger and more synchronous gamma oscillations were observed in DEPDC5 and NPRL3 mutations carriers. Conclusions: These results suggest that DEPDC5 and NPRL3-related epileptic mTORopathies may not directly modulate GABAergic functions but are nonetheless characterized by a stronger neural entrainment that may be reflective of a cortical hyperexcitability mediated by increased mTORC1 signaling. [ABSTRACT FROM AUTHOR]

Background: Acute Kawasaki disease (KD) induces central nervous system inflammation and excessive irritability. Long‐term impacts on children's neurodevelopment have only been studied marginally. This pilot study aimed to describe the neuropsychological profile of primary school‐aged children with a history of KD and to explore the impacts of KD on electroencephalography (EEG) markers associated with attention and brain maturation. Methods: Fifteen children (8.8 ± 2.5 years) were recruited 4.9 ± 2.7 years after KD onset. Intellectual abilities, long‐term memory, and auditory sustained attention were evaluated. Parents completed standardized questionnaires assessing (1) executive functioning; (2) internalizing and externalizing difficulties; (3) attention deficit hyperactivity disorder symptoms; and (4) autism spectrum disorder symptoms. Theta/beta ratio (TBR) and alpha peak (AP) were extracted from resting‐state EEG and compared with 32 controls (8.9 ± 2.1 years). The alpha band was analyzed using a feature reduction algorithm to detect potential groupings. Results: Performances showed preserved intellectual abilities and memory. Sustained attention performance was within the lower range for 4/14 participants (29%), with considerable parental reports of inattention (43%), working memory difficulties (50%), and hyperactivity‐impulsivity (36%). No alterations in the TBR were found but the KD group presented a significantly lower AP amplitude ratio. A clear separation of KD cohort into two clusters showed that acute irritability is associated with a weaker AP. Conclusions: Despite overall preserved cognitive functions, there is a possible association between KD and attention deficit concerns. This first EEG‐based study indicates alpha peak abnormality after KD, predominantly in children with acute irritability. Longitudinal studies are warranted to better characterize patients' neurodevelopmental trajectory. [ABSTRACT FROM AUTHOR]

Background: Neurofibromatosis type 1 (NF1) is a genetic disorder often associated with cognitive dysfunctions, including a high occurrence of deficits in visuoperceptual skills. The neural underpinnings of these visuoperceptual deficits are not fully understood. We used steady-state visual evoked potentials (SSVEPs) to investigate possible alterations in the synchronization of neural activity in the occipital cortex of children with NF1. Methods: SSVEPs were measured using electroencephalography and compared between children with NF1 (n = 28) and neurotypical controls (n = 28) aged between 4 and 13 years old. SSVEPs were recorded during visual stimulation with coloured icons flickering at three different frequencies (6 Hz, 10 Hz, and 15 Hz) and analyzed in terms of signal-to-noise ratios. A mixed design ANCOVA was performed to compare SSVEP responses between groups at the three stimulation frequencies. Pearson's correlations with levels of intellectual functioning as well as with symptoms of ADHD, ASD and emotional/behavioral problems were performed. The impact of psychostimulant medication on the SSVEP responses was analyzed in a subset of the NF1 group (n = 8) with paired t-tests. Results: We observed reduced signal-to-noise ratios of the SSVEP responses in children with NF1. The SSVEP responses were negatively correlated with symptoms of inattention and with symptoms of emotional/behavioral problems in the NF1 group. The SSVEP response generated by the lowest stimulation frequency (i.e., 6 Hz) was rescued with the intake of psychostimulant medication. Conclusions: Impaired processing of rhythmic visual stimulation was evidenced in children with NF1 through measures of SSVEP responses. Those responses seem to be more reduced in children with NF1 who exhibit more symptoms of inattention and emotional/behavioral problems in their daily life. SSVEPs are potentially sensitive electrophysiological markers that could be included in future studies investigating the impact of medication on brain activity and cognitive functioning in children with NF1. [ABSTRACT FROM AUTHOR]

Macrocephaly is present in about 2–5% of the general population. It can be found as an isolated benign trait or as part of a syndromic condition. Brain overgrowth has been associated with neurodevelopmental disorders such as autism during the first year of life, however, evidence remains inconclusive. Furthermore, most of the studies have involved pathological or high-risk populations, but little is known about the effects of brain overgrowth on neurodevelopment in otherwise neurotypical infants. We investigated the impact of brain overgrowth on basic perceptual learning processes (repetition effects and change detection response) during the first year of life. We recorded high density electroencephalograms (EEG) in 116 full-term healthy infants aged between 3 and 11 months, 35 macrocephalic (14 girls) and 81 normocephalic (39 girls) classified according to the WHO head circumference norms. We used an adapted oddball paradigm, time-frequency analyses, and auditory event-related brain potentials (ERPs) to investigate differences between groups. We show that brain overgrowth has a significant impact on repetition effects and change detection response in the 10–20 Hz frequency band, and in N450 latency, suggesting that these correlates of sensorial learning processes are sensitive to brain overgrowth during the first year of life. [ABSTRACT FROM AUTHOR]

Childhood cancer survivors should be routinely screened for psychological distress. However, existing screening tools promoted by cancer care institutions, such as the Distress Thermometer (DT) generate high rates of errors. The aim of this study is to help refining strategies of screening psychological distress in this population by exploring two-step methods combining the DT on step #1 with one question on step #2. Data from 255 survivors of childhood acute lymphoblastic leukemia aged 13–40 years were analyzed (38% 13–18 years, 62% 19+ years, 53% females). We used the DT on step #1 and the individual emotion items from the Pediatric Quality of Life Questionnaire (PedsQL) on step #2, to detect distress, depression and anxiety as measured by standard instruments. We compared sensitivity, specificity, negative and positive predictive values, Youden index, and clinical utility indices, in newly developed two-step strategies. The best two-step strategies to screen anxious-depressive distress were DT ≥ 2 on step #1, with the item of Sadness on step #2, and DT ≥ 2 combined with the item of Concerns. Two-step strategies outperformed the DT alone on the correct identification of distressed survivors. However, two-step strategies did not outperform the DT used alone on the correct detection of no distressed survivors. Results were similar when predicting depression or anxiety alone. Completing the DT with one single question on emotions from the PedsQL may minimize the number of participants falsely identified as distressed, which could be particularly pertinent in resource-limited clinics. [ABSTRACT FROM AUTHOR]

Amongst the numerous genes associated with intellectual disability, SYNGAP1 stands out for its frequency and penetrance of loss-of-function variants found in patients, as well as the wide range of co-morbid disorders associated with its mutation. Most studies exploring the pathophysiological alterations caused by Syngap1 haploinsufficiency in mouse models have focused on cognitive problems and epilepsy; however, whether and to what extent sensory perception and processing are altered by Syngap1 haploinsufficiency is less clear. By performing EEG recordings in awake mice, we identified specific alterations in multiple aspects of auditory and visual processing, including increased baseline gamma oscillation power, increased theta/gamma phase amplitude coupling following stimulus presentation and abnormal neural entrainment in response to different sensory modality-specific frequencies. We also report lack of habituation to repetitive auditory stimuli and abnormal deviant sound detection. Interestingly, we found that most of these alterations are present in human patients as well, thus making them strong candidates as translational biomarkers of sensory-processing alterations associated with SYNGAP1/Syngap1 haploinsufficiency. [ABSTRACT FROM AUTHOR]

Verbal fluency (VF) is a heterogeneous cognitive function that requires executive as well as language abilities. The purpose of this study was to elucidate the specificity of the resting state MEG correlates of the executive and language components. To this end, we administered a VF test, another verbal test (Vocabulary), and another executive test (Trail Making Test), and we recorded 5-min eyes-open resting-state MEG data in 28 healthy participants. We used source-reconstructed spectral power estimates to compute correlation/anticorrelation MEG clusters with the performance at each test, as well as with the advantage in performance between tests, across individuals using cluster-level statistics in the standard frequency bands. By obtaining conjunction clusters between verbal fluency scores and factor loading obtained for verbal fluency and each of the two other tests, we showed a core of slow clusters (delta to beta) localized in the right hemisphere, in adjacent parts of the premotor, pre-central and post-central cortex in the mid-lateral regions related to executive monitoring. We also found slow parietal clusters bilaterally and a cluster in the gamma 2 and 3 bands in the left inferior frontal gyrus likely associated with phonological processing involved in verbal fluency. [ABSTRACT FROM AUTHOR]

Introduction: Fragile X syndrome (FXS) is a genetic disorder caused by a mutation of the fragile X mental retardation 1 gene (FMR1). FXS is associated with neurophysiological abnormalities, including cortical hyperexcitability. Alterations in electroencephalogram (EEG) resting-state power spectral density (PSD) are well-defined in FXS and were found to be linked to neurodevelopmental delays. Whether non-linear dynamics of the brain signal are also altered remains to be studied. Methods: In this study, resting-state EEG power, including alpha peak frequency (APF) and theta/beta ratio (TBR), as well as signal complexity using multi-scale entropy (MSE) were compared between 26 FXS participants (ages 5–28 years), and 7 neurotypical (NT) controls with a similar age distribution. Subsequently a replication study was carried out, comparing our cohort to 19 FXS participants independently recorded at a different site. Results: PSD results confirmed the increased gamma, decreased alpha power and APF in FXS participants compared to NT controls. No alterations in TBR were found. Importantly, results revealed reduced signal complexity in FXS participants, specifically in higher scales, suggesting that altered signal complexity is sensitive to brain alterations in this population. The replication study mostly confirmed these results and suggested critical points of stagnation in the neurodevelopmental curve of FXS. Conclusion: Signal complexity is a powerful feature that can be added to the electrophysiological biomarkers of brain maturation in FXS. [ABSTRACT FROM AUTHOR]

Repetition effects and change detection response have been proposed as neuro‐electrophysiological correlates of fundamental learning processes. As such, they could be a good predictor of brain maturation and cognitive development. We recorded high density EEG in 71 healthy infants (32 females) aged between 3 and 9 months, while they listened to vowel sequences (standard /a/a/a/i/ [80%] and deviant /a/a/a/a/ [20%]). Adaptive skills, a surrogate of cognitive development, were measured via the parent form of the Adaptive Behavior Assessment System Second Edition (ABAS‐II). Cortical auditory‐evoked potentials (CAEPs) analyses, time‐frequency analyses and a statistical approach using linear mixed models (LMMs) and linear regression models were performed. Age and adaptive skills were tested as predictors. Age modulation of repetition effects and change detection response was observed in theta (3–5 Hz), alpha (5–10 Hz) and high gamma (80–90 Hz) oscillations and in all CAEPs. Moreover, adaptive skills modulation of repetition effects was evidenced in theta (3–5 Hz), high gamma oscillations (80–90 Hz), N250/P350 peak‐to‐peak amplitude and P350 latency. Finally, adaptive skills modulation of change detection response was observed in the N250/P350 peak‐to‐peak amplitude. Our results confirm that repetition effects and change detection response evolve with age. Moreover, our results suggest that repetition effects and change detection response vary according to adaptive skills displayed by infants during the first year of life, demonstrating their predictive value for neurodevelopment. [ABSTRACT FROM AUTHOR]

Self‐reported maternal prenatal stress (MPS) has been associated with earlier febrile seizure (FS) age of onset in offspring. Studies are needed to understand how the biological systems associated with exposure to psychological MPS are linked to seizure disorders in children. The present study aimed to investigate whether placental markers of MPS are linked to FS incidence and age at first occurrence. A subsample of children with FS (n = 28) and matched controls (n = 84), were drawn from the longitudinal 3D pregnancy cohort (N = 2366 mother–child dyads). Expression of placental genes associated with glucocorticoids, serotonin and fetal/placental growth were analysed from placental tissues, compared between groups and associated with age at first FS. Overall placental normalized gene expression was statistically different (p <.001). Children with FS showed overexpression of the serotonin transporter (mean difference = 0.61, 95% confidence interval [CI] = 0.9–1.13), connexin 43 (mean difference = 0.69, 95% CI = 0.30–1.09), zonula occludens‐1 (mean difference = 0.84, 95% CI = 0.42–1.26) and underexpression of glucocorticoid receptor β (mean difference = 0.84, 95% CI = −1.49 to 0.19) and serotonin receptor 2B (mean difference = 1.57, 95% CI = −2.35 to 0.78) compared to controls. Increased expression of the serotonin transporter predicted 37.2% in variation of age at first FS. The correlation matrix showed pregnancy‐specific anxiety during the second trimester was moderately associated with age at first FS (r = −0.38) but was not a significant predictor in the regression model. Although our current results do not display a significant effect of self‐reported MPS on FS, the present study is the first to show that placental gene biomarkers usually known to be associated with MPS display different expressions in children with FS. Specifically, our results suggest that placental genes associated with the glucocorticoid, serotonergic and fetal/placental growth systems may be candidate mechanisms leading to increased vulnerability offspring in FS. Because self‐reported MPS was not found as a significant predictor in our statistical models, future studies are needed to investigate the mechanisms causing the observed changes in placental genes and their association with seizure disorders. [ABSTRACT FROM AUTHOR]

Motivation Investigating the relationships between two sets of variables helps to understand their interactions and can be done with canonical correlation analysis (CCA). However, the correlation between the two sets can sometimes depend on a third set of covariates, often subject-related ones such as age, gender or other clinical measures. In this case, applying CCA to the whole population is not optimal and methods to estimate conditional CCA, given the covariates, can be useful. Results We propose a new method called Random Forest with Canonical Correlation Analysis (RFCCA) to estimate the conditional canonical correlations between two sets of variables given subject-related covariates. The individual trees in the forest are built with a splitting rule specifically designed to partition the data to maximize the canonical correlation heterogeneity between child nodes. We also propose a significance test to detect the global effect of the covariates on the relationship between two sets of variables. The performance of the proposed method and the global significance test is evaluated through simulation studies that show it provides accurate canonical correlation estimations and well-controlled Type-1 error. We also show an application of the proposed method with EEG data. Availability and implementation RFCCA is implemented in a freely available R package on CRAN (https://CRAN.R-project.org/package=RFCCA). Supplementary information Supplementary data are available at Bioinformatics online. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to: (1) describe the domains and levels of unmet needs of young adult survivors of childhood acute lymphoblastic leukemia (cALL) with comorbidities, and (2) to explore the factors associated with higher levels of unmet needs. Unmet need was considered as supportive care needs not met. Methods: The most vulnerable cALL survivors from the PETALE study cohort completed the Short-Form Survivor Unmet Needs Survey, the Brief Pain Inventory and the 15D instrument of health-related quality of life. Demographic and clinical information, including comorbidities, were obtained from medical records or self-reporting. The participants' needs and contributing factors to their needs were evaluated using nonparametric tests. Results: Of the 72 participants, 9 (13%) reported moderate/high levels of overall unmet needs. "Worry about earning money" (56%) and "Dealing with feeling tired" (51%) were the most frequent unmet needs (all levels combined). The factors associated significantly with any domain of unmet needs were: having a comorbidity, reporting altered functional health status, high ALL risk status, pain, age (<26 years), and having previously received psychological support. Conclusion: A minority of young adult survivors of cALL with comorbidities interviewed reported moderate/high levels of unmet needs. However, financial concerns and emotional health and relationship are the two domains of greatest need. Survivors with altered health condition are most at risk of experiencing moderate/high levels of unmet needs. If confirmed in larger samples, interventions should target modifiable contributors of unmet needs such as physical health and comfort, fatigue, and emotional health. [ABSTRACT FROM AUTHOR]

Objectives: Primary objective of this pilot study is to evaluate the feasibility and acceptability of the NeuroN‐QI and the study procedures. Secondary objectives are to assess the feasibility and acceptability of the NeuroN‐QI by the nurses, assess the nurses' training needs about the components of the NeuroN‐QI, and estimate the preliminary effects of the NeuroN‐QI on infants' neurodevelopment as well as maternal stress and anxiety at infants' 36 weeks of gestational age. Design: A two‐group pilot parallel randomized clinical trial stratified by center. Methods: The pilot study will be conducted in two neonatal intensive care units (NICUs). A sample of 24 mother–infant dyads born between 26 and 316/7 gestational age will be randomized into an experimental or control group. Fifty nurses will be recruited. The NeuroN‐QI consists of four 2‐hour skin‐to‐skin contact sessions/week with a 15‐minute auditory stimulation by mothers with controlled ambient levels of light and noise. A 1‐hour quiet period will follow where infants will rest in their incubator/crib with their mother's milk for olfactory stimulation and where the light and noise control will be continued. In the control group, mother–infant dyads will do four skin‐to‐skin contacts per week and receive standard care. Acceptability and feasibility of the NeuroN‐QI in addition to maternal stress and anxiety will be measured through questionnaires, while infants' neurodevelopment will be assessed with Assessment of Preterm Infant Behaviour and General Movement Assessment. Conclusions: This pilot trial will address knowledge gaps and generate evidence in neonatal care by evaluating the feasibility and acceptability of a multi‐component developmental care intervention. Impact: This project is an innovative step towards optimizing the neurodevelopmental trajectory of infants in NICUs and consequently promoting their long‐term health outcomes. Trial Registration: NCT04593095. [ABSTRACT FROM AUTHOR]

Developmental coordination disorder (DCD) is a neurodevelopmental disorder affecting primarily motor skills, but attentional and executive impairments are common in affected individuals. Moreover, the presence of neurodevelopmental comorbidities is frequent in this population, which certainly influences the cognitive profile of the children concerned. Previous studies have reported deficits in visuospatial/nonverbal and planning tasks. This systematic review of the literature aims to determine if impairments can be found in other attentional and executive functions as well. The type of cognitive tasks, the tasks' modality (verbal/nonverbal), and the influence of comorbid disorders on attentional and executive profiles are systematically considered. Forty-one studies were identified through the PubMed/Medline and PsycINFO databases according to pre-established eligibility criteria. The results reveal weaknesses in inhibitory control, working memory, planning, nonverbal fluency, and general executive functioning in children with DCD. The presence of comorbid disorders seemingly contributes to the verbal working memory difficulties findings. This review contributes to a better understanding of the cognitive impairments in DCD and of the needs of children with this disorder, allowing to optimize practitioners' therapeutic interventions. [ABSTRACT FROM AUTHOR]

This study investigated which specific behavioural issues is best associated with adaptive functioning in three specific genetic syndromes. Behavioural issues were assessed in neurotypical (NT) (n = 43), Tuberous sclerosis complex (TSC) (n = 19), Down syndrome (DS) (n = 24) and Fragile X syndrome (FXS) (n = 23) participants ranging from 3 to 30 years of age. First, we compared the behaviours characteristics between these genetic conditions and also according to age within these clinical groups. Multiple regressions included five behavioural scales (CBCL/BSI) and IQ as factors associated with adaptive functioning (ABAS-II's composite scores). These regressions were carried out in order to observe which behavioural characteristics are associated with adaptive functioning in each syndrome. Results showed specific behavioural profiles between syndromes but no differences between ages within syndromes. Results also showed that IQ and inattention/ hyperactivity accounted for a large amount of variance of adaptive functioning in TSC and FXS groups in almost all adaptive domains. A lower IQ and more issues in attention and hyperactivity were associated with a lower adaptive functioning. These results are consistent with existing literature on adaptive functioning through neurodevelopmental disorders (Chromik et al. 2019; Stein et al. 1995; Sikora et al. 2012; Liss et al. 2001; Kanne et al. 2011). Results linking social issues and anxiety to adaptive functioning remained inconsistent. [ABSTRACT FROM AUTHOR]

Survivors of childhood acute lymphoblastic leukemia (cALL) are at higher risk of developing cardiometabolic complications. We aimed at exploring the associations between biomarkers of inflammation, oxidative stress, endothelial function, endotoxemia and cardiometabolic risk factors. We conducted a cross-sectional analysis in 246 cALL survivors (mean age, 22.1 ± 6.3 years; mean time since diagnosis, 15.5 ± 5.2 years) and evaluated the associations using a series of logistic regressions. Using structural equation models, we also tested if the relationship between endotoxemia and cardiometabolic complications was mediated by the latent (unobserved) variable inflammation inferred from the observed biomarkers CRP, TNF-α and IL-6. High leptin-adiponectin ratio was associated with obesity [adjusted OR = 15.7; 95% CI (6.2–39.7)], insulin resistance [20.6 (5.2–82.1)] and the metabolic syndrome [11.2 (2.6–48.7)]. Higher levels of plasminogen activator inhibitor-1 and tumor necrosis factor-α were associated with obesity [3.37 (1.6–7.1) and 2.34 (1.3–4.2), respectively] whereas high C-reactive protein levels were associated with insulin resistance [3.3 (1.6–6.8)], dyslipidemia [2.6 (1.4–4.9)] and MetS [6.5 (2.4–17.9)]. Our analyses provided evidence for a directional relationship between lipopolysaccharide binding protein, related to metabolic endotoxemia, inflammation and cardiometabolic outcomes. Identification of biomarkers and biological mechanisms could open new avenues for prevention strategies to minimize the long-term sequelae, improve follow-up and optimize the quality of life of this high-risk population. [ABSTRACT FROM AUTHOR]

Speech perception relies on auditory and visual cues and there are strong links between speech perception and production. We aimed to evaluate the role of auditory and visual modalities on speech perception and production in adults with impaired hearing or sight versus those with normal hearing and sight. We examined speech perception and production of three isolated vowels (/i/, /y/, /u/), which were selected based on their different auditory and visual perceptual saliencies, in 12 deaf adults who used one or two cochlear implants (CIs), 14 congenitally blind adults, and 16 adults with normal sight and hearing. The results showed that the deaf adults who used a CI had worse vowel identification and discrimination perception and they also produced vowels that were less typical or precise than other participants. They had different tongue positions in speech production, which possibly partly explains the poorer quality of their spoken vowels. Blind individuals had larger lip openings and smaller lip protrusions for the rounded vowel and unrounded vowels, compared to the other participants, but they still produced vowels that were similar to those produced by the adults with normal sight and hearing. In summary, the deaf adults, even though they used CIs, had greater difficulty in producing accurate vowel targets than the blind adults, whereas the blind adults were still able to produce accurate vowel targets, even though they used different articulatory strategies. [ABSTRACT FROM AUTHOR]

Introduction. Most childhood acute lymphoblastic leukemia (ALL) survivors develop chronic treatment-related adverse effects several years after the end of the treatment. Regular physical activity and a good cardiorespiratory fitness can decrease the risks of neurological disturbances and increase cognitive function scores. The aim of this study was to examine the effect of good cardiorespiratory fitness and physical activity levels on cognitive functions. Methods. We enrolled 219 survivors of childhood ALL. The participants underwent a cardiopulmonary exercise test, neuropsychological tests of executive functions (i.e. verbal fluency, cognitive flexibility, working memory, processing speed) and completed a physical activity questionnaire. We calculated the odds ratio to obtain the preventive fraction of physical activity and cardiorespiratory fitness levels on cognitive functions. Results. The cohort is 52% male and 48% female. A total of 182 survivors (83%) have a cardiorespiratory fitness below their predicted (<100%). Our analyses show that there is an association between good cardiorespiratory fitness and processing speed (preventive fraction of 70% for dominant hand (p < 0.01) and 65% for non-dominant hand (p < 0.01)) and with cognitive flexibility identified as the category switching measure of the D-KEFS verbal fluency (preventive fraction of 61%; p < 0.05). Conclusion. Good cardiorespiratory fitness and good levels of physical activity were associated to a preventive fraction for most cognitive function parameters measured. Good cardiorespiratory fitness levels were significantly associated with a lower prevalence of deficits in processing speed (i.e., dominant hand and non-dominant hand) and in cognitive flexibility (i.e., category switching) in childhood acute lymphoblastic leukemia survivors. [ABSTRACT FROM AUTHOR]

Objectives: The frequency of cognitive difficulties in childhood cancer survivors varies according to the measurement strategy. The goal of this research is to (a) describe agreements and differences between measures of working memory and attention (b) identify contributors of these differences, such as emotional distress, affects, and fatigue.Methods: We used data available for 138 adults successfully treated for childhood acute lymphoblastic leukemia (ALL) (PETALE cohort). Working memory and attention were assessed using subtests from the WAIS-IV and self-reported questionnaires (BRIEF-SR and CAARS-S:L). Potential contributors included emotional distress, anxiety, depression (BSI-18), affects (PANAS), and fatigue (PedsQL-MFS). We explored measurement agreements and differences using diagnostic indices and multivariate regression models.Results: The frequencies of working memory and attention deficits were higher when using cognitive tests (15%-21%) than with self-reports (10%-11%). Self-reported questionnaires showed high specificity (median 0.87) and low sensitivity (median 0.10), suggesting they did not reliably identify positive cases on cognitive tests. We identified negative affectivity as a possible contributor to inconsistencies between self-report and test results.Conclusions: When measuring working memory and attention in childhood ALL survivors, cognitive test results and self-reports should not be considered equivalent. At best, self-report may be used for screening (high specificity), but not to assess prevalence in large samples. Self-reported difficulties are also probably influenced by the negative mood in this population. [ABSTRACT FROM AUTHOR]

Background: Pediatric low-grade gliomas (PLGG) are the most frequent brain tumors in children. Up to 50% will be refractory to conventional chemotherapy. It is now known that the majority of PLGG have activation of the MAPK/ERK pathway. The same pathway is also activated in plexiform neurofibromas (PNs) which are low-grade tumors involving peripheral nerves in patients with neurofibromatosis type 1 (NF1). These lesions are known to be refractory to chemotherapy. Specific MEK inhibitors such as trametinib are now available and have been approved for other cancers harboring mutations in the MAPK/ERK pathway such as melanoma. We have observed significant responses to trametinib in patients with refractory PLGG in our institutions and results from the phase I study are promising. The treatment appears not only efficacious but is also usually well tolerated. We hypothesize that we will observe responses in the majority of refractory PLGG and PN treated with trametinib in this phase 2 study.Methods: The primary objective is to determine the objective response rate of trametinib as a single agent for treatment of progressing/refractory tumors with MAPK/ERK pathway activation. The TRAM-01 study is a phase II multicentric open-label basket trial including four groups. Group 1 includes NF1 patients with progressing/refractory glioma. Group 2 includes NF1 patients with plexiform neurofibroma. Group 3 includes patients with progressing/refractory glioma with KIAA1549-BRAF fusion. Group 4 includes other patients with progressing/refractory glioma with activation of the MAPK/ERK pathway. Eligible patients for a given study group will receive daily oral trametinib at full dose for a total of 18 cycles of 28 days. A total of 150 patients will be enrolled in seven Canadian centers. Secondary objectives include the assessment of progression-free survival, overall survival, safety and tolerability of trametinib, serum levels of trametinib and evaluation of quality of life during treatment.Discussion: Trametinib will allow us to target directly and specifically the MAPK/ERK pathway. We expect to observe a significant response in most patients. Following our study, trametinib could be integrated into standard treatment of PLGG and PN.Trial Registration: ClinicalTrials.gov Identifier: NCT03363217 December 6, 2017. [ABSTRACT FROM AUTHOR]

Background: Acute lymphoblastic leukemia (ALL) is the most common childhood cancer. Treatments against ALL might lead to later cognitive effects and alterations in brain structure in survivors but to the authors' knowledge the observed variability in the severity of neurocognitive deficits is not fully understood. The objective of the current study was to investigate abnormalities in visual short-term memory (VSTM) brain activation in survivors of childhood ALL using magnetoencephalography.Methods: A VSTM task was completed by 40 survivors of ALL and 26 controls. VSTM capacity (Cowan K) and brain activation were assessed during the retention period of the task (400-1400 milliseconds) using a standard minimum norm source localization method.Results: Performance (Cowan K) was found to be similar between survivors of ALL and controls. Atypical brain activation was found in survivors of ALL during the task, including overactivation of regions usually involved in VSTM (lateral occipital, precentral gyrus, and postcentral gyrus), recruitment of regions that typically are not involved in VSTM (superior/middle temporal gyrus and supramarginal gyrus), and lower activation of frontal brain regions (inferior frontal gyrus). These patterns of activation were modulated by the age at the time of cancer onset (P = .01) because activity was found to be reduced in participants who were younger at diagnosis.Conclusions: The results of the current study suggest a pattern of neural inefficiency and compensatory activity during VSTM in survivors of ALL. [ABSTRACT FROM AUTHOR]

Background: A substantial number of survivors of childhood acute lymphoblastic leukemia suffer from treatment-related late adverse effects including neurocognitive impairment. While multiple studies have described neurocognitive outcomes in childhood acute lymphoblastic leukemia (ALL) survivors, relatively few have investigated their association with individual genetic constitution. Methods: To further address this issue, genetic variants located in 99 genes relevant to the effects of anticancer drugs and in 360 genes implicated in nervous system function and predicted to affect protein function, were pooled from whole exome sequencing data of childhood ALL survivors (PETALE cohort) and analyzed for an association with neurocognitive complications, as well as with anxiety and depression. Variants that sustained correction for multiple testing were genotyped in entire cohort (n = 236) and analyzed with same outcomes. Results: Common variants in MTR, PPARA, ABCC3, CALML5, CACNB2 and PCDHB10 genes were associated with deficits in neurocognitive tests performance, whereas a variant in SLCO1B1 and EPHA5 genes was associated with anxiety and depression. Majority of associations were modulated by intensity of treatment. Associated variants were further analyzed in an independent SJLIFE cohort of 545 ALL survivors. Two variants, rs1805087 in methionine synthase, MTR and rs58225473 in voltage-dependent calcium channel protein encoding gene, CACNB2 are of particular interest, since associations of borderline significance were found in replication cohort and remain significant in combined discovery and replication groups (OR = 1.5, 95% CI, 1–2.3; p = 0.04 and; OR = 3.7, 95% CI, 1.25–11; p = 0.01, respectively). Variant rs4149056 in SLCO1B1 gene also deserves further attention since previously shown to affect methotrexate clearance and short-term toxicity in ALL patients. Conclusions: Current findings can help understanding of the influence of genetic component on long-term neurocognitive impairment. Further studies are needed to confirm whether identified variants may be useful in identifying survivors at increased risk of these complications. [ABSTRACT FROM AUTHOR]

Background: Fragile X syndrome (FXS) is a neurodevelopmental genetic disorder causing cognitive and behavioural deficits. Repetition suppression (RS), a learning phenomenon in which stimulus repetitions result in diminished brain activity, has been found to be impaired in FXS. Alterations in RS have been associated with behavioural problems in FXS; however, relations between RS and intellectual functioning have not yet been elucidated. Methods: EEG was recorded in 14 FXS participants and 25 neurotypical controls during an auditory habituation paradigm using repeatedly presented pseudowords. Non-phased locked signal energy was compared across presentations and between groups using linear mixed models (LMMs) in order to investigate RS effects across repetitions and brain areas and a possible relation to non-verbal IQ (NVIQ) in FXS. In addition, we explored group differences according to NVIQ and we probed the feasibility of training a support vector machine to predict cognitive functioning levels across FXS participants based on single-trial RS features. Results: LMM analyses showed that repetition effects differ between groups (FXS vs. controls) as well as with respect to NVIQ in FXS. When exploring group differences in RS patterns, we found that neurotypical controls revealed the expected pattern of RS between the first and second presentations of a pseudoword. More importantly, while FXS participants in the ≤ 42 NVIQ group showed no RS, the > 42 NVIQ group showed a delayed RS response after several presentations. Concordantly, single-trial estimates of repetition effects over the first four repetitions provided the highest decoding accuracies in the classification between the FXS participant groups. Conclusion: Electrophysiological measures of repetition effects provide a non-invasive and unbiased measure of brain responses sensitive to cognitive functioning levels, which may be useful for clinical trials in FXS. [ABSTRACT FROM AUTHOR]

Repeated visual processing of an unfamiliar face suppresses neural activity in face-specific areas of the occipito-temporal cortex. This "repetition suppression" (RS) is a primitive mechanism involved in learning of unfamiliar faces, which can be detected through amplitude reduction of the N170 event-related potential (ERP). The dorsolateral prefrontal cortex (DLPFC) exerts top-down influence on early visual processing. However, its contribution to N170 RS and learning of unfamiliar faces remains unclear. Transcranial direct current stimulation (tDCS) transiently increases or decreases cortical excitability, as a function of polarity. We hypothesized that DLPFC excitability modulation by tDCS would cause polarity-dependent modulations of N170 RS during encoding of unfamiliar faces. tDCS-induced N170 RS enhancement would improve long-term recognition reaction time (RT) and/or accuracy rates, whereas N170 RS impairment would compromise recognition ability. Participants underwent three tDCS conditions in random order at ∼72 hour intervals: right anodal/left cathodal, right cathodal/left anodal and sham. Immediately following tDCS conditions, an EEG was recorded during encoding of unfamiliar faces for assessment of P100 and N170 visual ERPs. The P3a component was analyzed to detect prefrontal function modulation. Recognition tasks were administered ∼72 hours following encoding. Results indicate the right anodal/left cathodal condition facilitated N170 RS and induced larger P3a amplitudes, leading to faster recognition RT. Conversely, the right cathodal/left anodal condition caused N170 amplitude and RTs to increase, and a delay in P3a latency. These data demonstrate that DLPFC excitability modulation can influence early visual encoding of unfamiliar faces, highlighting the importance of DLPFC in basic learning mechanisms. [ABSTRACT FROM AUTHOR]

Fragile X Syndrome (FXS) is the most common form of X-linked intellectual disability (ID), associated with a wide range of cognitive and behavioral impairments. FXS is caused by a trinucleotide repeat expansion in the FMR1 gene located on the X-chromosome. FMR1 is expected to prevent the expression of the "fragile X mental retardation protein (FMRP)", which results in altered structural and functional development of the synapse, including a loss of synaptic plasticity. This review aims to unveil the contribution of electrophysiological signal studies for the understanding of the information processing impairments in FXS patients. We discuss relevant event-related potential (ERP) studies conducted with full mutation FXS patients and clinical populations sharing symptoms with FXS in a developmental perspective. Specific deviances found in FXS ERP profiles are described. Alterations are reported in N1, P2, Mismatch Negativity (MMN), N2, and P3 components in FXS compared to healthy controls. Particularly, deviances in N1 and P2 amplitude seem to be specific to FXS. The presented results suggest a cascade of impaired information processes that are in line with symptoms and anatomical findings in FXS. [ABSTRACT FROM AUTHOR]