Brain Regions In Children Research Articles

Functional connectivity density of brain in children with primary nocturnal enuresis: results from a resting-state fMRI study.

Primary nocturnal enuresis (PNE) is a disease characterized by involuntary urination during sleep after the age of five, causing inconvenience and psychological burden to children and their families. The onset of PNE is related to many factors, and in recent years, delayed central nervous system maturation has been considered one of the important causes of PNE. Previous studies have demonstrated functional changes in multiple brain regions in children with PNE. However, these studies either focused on changes in local brain regions or the functional connection (FC) between specific brain regions, and there is currently a lack of research on the whole brain FC in children with PNE. This study analyzed functional connectivity density (FCD) across the entire brain based on voxels and comprehensively evaluated the global FCD (gFCD), local FCD (lFCD), and long-range FCD (lrFCD). Decreased gFCD and lFCD were found in the left temporal lobe and the right posterior cerebellum in the children with PNE compared with the HC. The FCD values in these regions were negatively correlated with the scores of hyperactivity/impulsivity in the children with PNE. This study may help to reveal the neural mechanisms underlying the onset of PNE in children from a new perspective.

ADHD classification with cross-dataset feature selection for biomarker consistency detection

Objective. Attention deficit hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder in children. While numerous intelligent methods are applied for its subjective diagnosis, they seldom consider the consistency problem of ADHD biomarkers. In practice, these data-driven approaches lead to varying learned features for ADHD classification across diverse ADHD datasets. This phenomenon significantly undermines the reliability of identified biomarkers and hampers the interpretability of these methods. Approach. In this study, we propose a cross-dataset feature selection (FS) module using a grouped SVM-based recursive feature elimination approach (G-SVM-RFE) to enhance biomarker consistency across multiple datasets. Additionally, we employ connectome gradient data for ADHD classification. In details, we introduce the G-SVM-RFE method to effectively concentrate gradient components within a few brain regions, thereby increasing the likelihood of identifying these regions as ADHD biomarkers. The cross-dataset FS module is integrated into an existing binary hypothesis testing (BHT) framework. This module utilizes external datasets to identify global regions that yield stable biomarkers. Meanwhile, given a dataset which waits for implementing the classification task as local dataset, we learn its own specific regions to further improve the performance of accuracy on this dataset. Main results. By employing this module, our experiments achieve an average accuracy of 96.7% on diverse datasets. Importantly, the discriminative gradient components primarily originate from the global regions, providing evidence for the significance of these regions. We further identify regions with the high appearance frequencies as biomarkers, where all the used global regions and one local region are recognized. Significance. These biomarkers align with existing research on impaired brain regions in children with ADHD. Thus, our method demonstrates its validity by providing enhanced biological explanations derived from ADHD mechanisms.

Sleep Behaviors and the Shape of Subcortical Brain Structures in Children with Overweight/Obesity: A Cross-Sectional Study.

To examine the relationship between sleep and subcortical brain structures using a shape analysis approach. A total of 98 children with overweight/obesity (10.0 ± 1.1 y, 59 boys) were included in the cross-sectional analyses. Sleep behaviors (i.e., wake time, sleep onset time, total time in bed, total sleep time, sleep efficiency, and wakening after sleep onset) were estimated with wrist-worn accelerometers. The shape of the subcortical brain structures was acquired by magnetic resonance imaging. A partial correlation permutation approach was used to examine the relationship between sleep behaviors and brain shapes. Among all the sleep variables studied, only total time in bed was significantly related to pallidum and putamen structure, such that those children who spent more time in bed had greater expansions in the right and left pallidum (211-751 voxels, all p's <0.04) and right putamen (1783 voxels, p = 0.03). These findings suggest that more time in bed was related to expansions on two subcortical brain regions in children with overweight/obesity.

Diffusion kurtosis imaging reveals abnormal gray matter and white matter development in some brain regions of children with attention-deficit/hyperactivity disorder.

In this study, we explored the application of diffusion kurtosis imaging (DKI) technology in the brains of children with attention-deficit/hyperactivity disorder (ADHD). Seventy-two children with ADHD and 79 age- and sex-matched healthy controls were included in the study. All children were examined by means of 3D T1-weighted image, DKI, and conventional sequence scanning. The volume and DKI parameters of each brain region were obtained by software postprocessing (GE ADW 4.6 workstation) and compared between the two groups of children to determine the imaging characteristics of children with ADHD. The result showed the total brain volume was lower in children with ADHD than in healthy children (p < .05). The gray and white matter volumes in the frontal lobe, temporal lobe, hippocampus, caudate nucleus, putamen, globus pallidus, and other brain regions were lower in children with ADHD than in healthy children (p < .05). The axial kurtosis (Ka), mean kurtosis (MK), fractional anisotropy (FA), and radial kurtosis(Kr) values in the frontal lobe, temporal lobe, and caudate nucleus of children with ADHD were lower than those of healthy children, while the mean diffusivity(MD) and fractional anisotropy of kurtosis (FAK) values were higher than those of healthy children (p < .05). Additionally, the Ka, MK, FA, and Kr values in the frontal lobe, caudate nucleus, and temporal lobe could be used to distinguish children with ADHD (AUC > .05, p < .05). In conclusion, DKI showed abnormal gray matter and white matter development in some brain regions of children with ADHD.

Cortical grey matter changes, behavior and cognition in children with sleep disordered breathing.

This paper investigated cortical thickness and volumetric changes in children to better understand the impact of obstructive sleep disordered breathing (SDB) on the neurodevelopment of specific regions of the brain. We also aimed to investigate how these changes were related to the behavioral and cognitive deficits observed in the condition. Neuroimaging, behavioral, and sleep data were obtained from 30 children (15 non-snoring controls, 15 referred for assessment of SDB) aged 7 to 17 years. Gyral-based regions of interest were identified using the Desikan-Killiany atlas. Student's t-tests were used to compare regions of interest between the controls and SDB groups. We found that the cortical thickness was significantly greater in the right caudal anterior cingulate and right cuneus regions and there were volumetric increases in the left caudal middle frontal, bilateral rostral anterior cingulate, left, right, and bilateral caudate brain regions in children with SDB compared with controls. Neither cortical thickness nor volumetric changes were associated with behavioral or cognitive measures. The findings of this study indicate disruptions to neural developmental processes occurring in structural regions of the brain; however, these changes appear unrelated to behavioural or cognitive outcomes.

Quantitative susceptibility mapping shows lower brain iron content in children with childhood epilepsy with centrotemporal spikes.

The dysregulation of brain iron homeostasis is closely relevant to a multitude of chronic neurological disorders. This study employed quantitative susceptibility mapping (QSM) to detect and compare whole-brain iron content between childhood epilepsy with centrotemporal spikes (CECTS) children and typically developing children. 32 children with CECTS and 25 age- and gender-matched healthy children were enrolled. All participants were imaged with 3.0-T MRI to acquire the structural and susceptibility-weighted data. The susceptibility-weighted data were processed using STISuite toolbox to obtain QSM. The magnetic susceptibility difference between the two groups was compared using voxel-wise and region of interest methods. Multivariable linear regression, controlling for age, were employed to investigate the associations between the brain magnetic susceptibility and age at onset. Lower magnetic susceptibility was mainly observed in sensory- and motor-related brain regions in children with CECTS, including bilateral middle frontal gyrus, supplementary motor area, midcingulate cortex, paracentral lobule and precentral gyrus, the magnetic susceptibility of right paracentral lobule, right precuneus and left supplementary motor area were found to have positive correlation with the age at onset. This study suggests that the potential iron deficiency in certain brain regions is associated with CECTS, which might be helpful for further illumination of potential pathogenesis mechanism of CECTS.

Quantitative susceptibility mapping reveals brain iron deficiency in children with attention-deficit/hyperactivity disorder: a whole-brain analysis.

To quantitatively measure and compare the whole-brain iron deposition between attention-deficit/hyperactivity disorder (ADHD) patients and typically developing (TD) children using the quantitative susceptibility mapping (QSM) technique. This study was approved by the institutional review board of our institution (No. [2019]328). Fifty-one patients between 6 and 14years with clinical diagnosis of ADHD and 51 age- and gender-paired TD children were enrolled. For each participant, the 3D T1 and multi-echo GRE sequence were performed to acquire the whole-brain data with 3.0-T MRI. The QSM maps were calculated using STISuite toolbox. After normalizing the QSM images to MNI space, the voxel-based analysis was used to compare the iron content between the two groups. Pearson's correlation test was used to assess the associations between the iron content and the score of the tablet-PC-based cancellation test, which was done to evaluate the attention concentration level. Iron deficiency was observed in several brain regions in children with ADHD, including bilateral striatums, anterior cingulum, olfactory gyrus, and right lingual gyri. In further correlation analysis, the left anterior cingulum was found to show positive correlation with the symptom severity (r = 0.326, p < 0.05). Our study demonstrated that the iron deficiency in several brain regions might be related with ADHD, which might be valuable for further studies. And QSM might have the potential efficacy in the auxiliary diagnosis of ADHD. • Iron deficiency was observed in several brain regions in children with ADHD, which include bilateral striatums, the critical regions in the dopaminergic transmitter system. • The iron content in the left ACG may have association with the symptom severity of ADHD. • QSM might have the potential efficacy in the auxiliary diagnosis of ADHD.

Association between lack of functional connectivity of the frontal brain region and poor response inhibition in children with frontal lobe epilepsy

PurposeWe investigated the relationship between electroencephalographic (EEG) functional connectivity and executive function in children with frontal lobe epilepsy (FLE). MethodsWe enrolled 24 children with FLE (mean age, 11.0 years; 13 boys) and 22 sex-, age-, and intelligence-matched typically developing children (TDC) to undergo 19-channel EEG during light sleep. We estimated functional connectivity using the phase lag index (PLI) that captures the synchronization of EEG. We also performed continuous performance tests (CPTs) on the children and obtained questionnaire responses on attention deficit hyperactivity disorder and oppositional defiant disorder (ODD). ResultsThe average gamma PLI was lower in the FLE group than in the TDC group, especially between long-distance frontoparietal pairs, between interhemispheric frontal pairs, and between interhemispheric parietotemporal pairs. Gamma PLIs with long-distance frontoparietal and interhemispheric frontal pairs were positively associated with inattention, ODD scores, omission error, and reaction time in the FLE group but not in the TDC group. Conversely, they were negatively associated with age, hyperactivity score, and commission error. ConclusionsA lack of functional connectivity of the frontal brain regions in children with FLE was associated with poor response inhibition.

Association of Pediatric Acute-Onset Neuropsychiatric Syndrome With Microstructural Differences in Brain Regions Detected via Diffusion-Weighted Magnetic Resonance Imaging

Epidemiological studies indicate a link between obsessive-compulsive disorder and infections, particularly streptococcal pharyngitis. Pediatric acute-onset neuropsychiatric syndrome (PANS) manifests suddenly with obsessions, compulsions, and other behavioral disturbances, often after an infectious trigger. The current working model suggests a unifying inflammatory process involving the central nervous system, particularly the basal ganglia. To investigate whether diffusion-weighted magnetic resonance imaging (DWI) detects microstructural abnormalities across the brain regions of children with PANS. Case-control study performed at a single-center, multidisciplinary clinic in the United States focusing on the evaluation and treatment of children with PANS. Sixty consecutive patients who underwent 3 Tesla (T) magnetic resonance imaging (MRI) before immunomodulation from September 3, 2012, to March 30, 2018, were retrospectively reviewed for study inclusion. Six patients were excluded by blinded investigators because of imaging or motion artifacts, 3 patients for major pathologies, and 17 patients for suboptimal atlas image registration. In total, 34 patients with PANS before initiation of treatment were compared with 64 pediatric control participants. Using atlas-based MRI analysis, regional brain volume, diffusion, and cerebral blood flow were measured in the cerebral white matter, cerebral cortex, thalamus, caudate, putamen, pallidum, hippocampus, amygdala, nucleus accumbens, and brainstem. An age and sex-controlled multivariable analysis of covariance was used to compare patients with control participants. This study compared 34 patients with PANS (median age, 154 months; age range, 55-251 months; 17 girls and 17 boys) and 64 pediatric control participants (median age, 139 months; age range, 48-213 months); 41 girls and 23 boys). Multivariable analysis demonstrated a statistically significant difference in MRI parameters between patients with PANS and control participants (F21,74 = 6.91; P < .001; partial η2 = 0.662). All assessed brain regions had statistically significantly increased median diffusivity compared with 64 control participants. Specifically, the deep gray matter (eg, the thalamus, basal ganglia, and amygdala) demonstrated the most profound increases in diffusivity consistent with the cardinal clinical symptoms of obsessions, compulsions, emotional dysregulation, and sleep disturbances. No statistically significant differences were found regarding volume and cerebral blood flow. This study identifies cerebral microstructural differences in children with PANS in multiple brain structures, including the deep gray matter structures (eg, the thalamus, basal ganglia, and amygdala). Further study of MRI is warranted in prospective, clinical trials as a potential quantitative method for assessing patients under evaluation for PANS.

Lean mass index is positively associated with white matter volumes in several brain regions in children with overweight/obesity.

The relationship of obesity with grey and white matter volumes has been examined in several studies, and the results are decidedly mixed. To investigate the associations of body mass index (BMI), fat mass index (FMI) and lean mass index (LMI) with total and regional grey and white matter volumes. This is a cross-sectional study involving 100 children (60% boys) with overweight/obesity. T1-weighted images were acquired using magnetic resonance imaging. Dual energy X-ray absorptiometry was used to measure body composition. Separate hierarchical regression analyses were performed between predictor variables (BMI, FMI and LMI) and the total brain volumes including sex, years from peak height velocity and parental education as covariates. In addition, FMI was added as a covariate when LMI was the predictor and vice versa. Statistical analyses of imaging data were performed using three whole-brain voxel-wise multiple regression models and adjusted by the same covariates. LMI was positively associated with white matter in numerous regions and to a lower extent, with grey matter regions. Further, the relationship between LMI, and grey and white matter regions was independent of FMI levels. LMI seems to be a positive predictor of regional white matter volumes in children with overweight/obesity.

Brain Imaging of the Cortex in ADHD: A Coordinated Analysis of Large-Scale Clinical and Population-Based Samples.

Neuroimaging studies show structural alterations of various brain regions in children and adults with attention deficit hyperactivity disorder (ADHD), although nonreplications are frequent. The authors sought to identify cortical characteristics related to ADHD using large-scale studies. Cortical thickness and surface area (based on the Desikan-Killiany atlas) were compared between case subjects with ADHD (N=2,246) and control subjects (N=1,934) for children, adolescents, and adults separately in ENIGMA-ADHD, a consortium of 36 centers. To assess familial effects on cortical measures, case subjects, unaffected siblings, and control subjects in the NeuroIMAGE study (N=506) were compared. Associations of the attention scale from the Child Behavior Checklist with cortical measures were determined in a pediatric population sample (Generation-R, N=2,707). In the ENIGMA-ADHD sample, lower surface area values were found in children with ADHD, mainly in frontal, cingulate, and temporal regions; the largest significant effect was for total surface area (Cohen's d=-0.21). Fusiform gyrus and temporal pole cortical thickness was also lower in children with ADHD. Neither surface area nor thickness differences were found in the adolescent or adult groups. Familial effects were seen for surface area in several regions. In an overlapping set of regions, surface area, but not thickness, was associated with attention problems in the Generation-R sample. Subtle differences in cortical surface area are widespread in children but not adolescents and adults with ADHD, confirming involvement of the frontal cortex and highlighting regions deserving further attention. Notably, the alterations behave like endophenotypes in families and are linked to ADHD symptoms in the population, extending evidence that ADHD behaves as a continuous trait in the population. Future longitudinal studies should clarify individual lifespan trajectories that lead to nonsignificant findings in adolescent and adult groups despite the presence of an ADHD diagnosis.

Changes in the functional connectivity of auditory and language-related brain regions in children with congenital severe sensorineural hearing loss: An fMRI study

Abstract Early hearing deprivation can affect the development of hearing, language, and vision. Thirty-four infants with congenital severe sensorineural hearing loss (CSSHL) and 20 age- and sex-matched subjects with normal hearing were recruited. The amplitude of low-frequency fluctuation (ALFF) of auditory and language-related brain areas was compared between infants with deafness and control subjects. Relative to subjects with normal hearing, infants with CSSHL had decreased ALFF values in the right Brodmann's area (BA) 22 region and in parts of several language-related regions. As the duration of hearing loss increased, the ALFF values in the left auditory and linguistic brain regions increased. These findings indicate that hearing deprivation affects the functional connectivity between auditory and language-related brain regions and the corresponding sensory and visual functional brain regions and that this functional connectivity decreases as the duration of hearing loss increases. Cochlear implantation performed after 24 months may limit the habilitation of hearing and speech functions due to functional reorganization of the auditory and linguistic brain areas over time.

Whole Exome Sequencing: Novel Genetic Polymorphisms in Saudi Arabian Attention Deficit Hyperactivity Disorder (ADHD) Children

Background: Attention-deficit hyperactivity disorder (ADHD) is a widespread and debilitating disorder with relatively high prevalence in Saudi Arabia. Neuropsychological and radiological investigations have revealed that there are some differences in the components of the brain regions in children with and without ADHD. In this study we have performed whole exome sequencing (WES) in four non-familial cases of ADHD from Makkah Region to identify the genetic polymorphisms associated with the disease in our Saudi population. Methods: Exome sequencing was carried out using Ion Proton with AmpliSeq Exome library methods, and the data were analysed by Ion Reporter 5.6 software. Results: A total of 33 variants were identified from 222 genes selected from the GWAS catalogue for ADHD associated genes. However, the SNPs we identified in these genes were not reported to be associated with ADHD in previous studies. We have identified 2 novel missense variants; one in c.3451G > T; p. (Ala1151Ser) in ITGA1 gene and another is c.988G > A; p. (Ala330Thr) in SPATA13 genes. The variants rs928661, rs11150370 and rs386792899 were the only three variants that appeared on all the 4 patients studied. Six missense variants, rs16841277, rs2228209, rs2230283, rs3741883, rs1716 and rs2272606, were found in 3 different patients, respectively. However, the three documented variants are rs13166360 with bipolar disorder, rs920829 with neuropathic pain, and rs6558702 with schizophrenia. Conclusion: We have identified 2 novel variants in ADHD children. SIFT score of all variants indicates that these substitutions have damaging effects on the protein function. Further screening studies are recommended for confirmation.

Mapping alterations of gray matter volume and white matter integrity in children with autism spectrum disorder

This study aimed to identify the neuroanatomical substrates and white matter connectivity in children with autism spectrum disorder (ASD) and the association between gray matter and structural connectivity. A total of 36 children including patients with ASD and healthy controls between 6 and 15 years of age were enrolled in this study. High-resolution structural MRI and functional MRI were performed and analyzed using voxel-based morphometry and tract-based spatial statistics. The relationship between gray matter volume and structural connectivity was generated using Pearson correlation analysis. Voxel-based morphometry analysis showed significantly reduced areas of gray matter in the left cerebellum. Tract-based spatial statistics analysis showed white matter abnormalities in several distinct clusters within the right inferior frontal gyrus (opercular part), the left inferior parietal lobule, and the right mentary motor area. Neither ASD nor healthy controls showed a significant correlation between gray matter volume and white matter integrity. Our study confirmed the presence of several structural and regional abnormalities in ASD children. These findings suggest that there are significant differences in some brain regions in children with autism relative to healthy children, but no association between them.

Modeling the connections of brain regions in children with autism using cellular neural networks and electroencephalography analysis.

The brain connections in the different regions demonstrate the characteristics of brain activities. In addition, in various conditions and with neuropsychological disorders, the brain has special patterns in different regions. This paper presents a model to show and compare the connection patterns in different brain regions of children with autism (53 boys and 36 girls) and control children (61 boys and 33 girls). The model is designed by cellular neural networks and it uses the proper features of electroencephalography. The results show that there are significant differences and abnormalities in the left hemisphere, (p < 0.05) at the electrodes AF3, F3, P7, T7, and O1 in the children with autism compared with the control group. Also, the evaluation of the obtained connections values between brain regions demonstrated that there are more abnormalities in the connectivity of frontal and parietal lobes and the relations of the neighboring regions in children with autism. It is observed that the proposed model is able to distinguish the autistic children from the control subjects with an accuracy rate of 95.1% based on the obtained values of CNN using the SVM method.

The focal alteration and causal connectivity in children with new-onset benign epilepsy with centrotemporal spikes

The aim of the current study was to find the epileptic focus and examine its causal relationship to other brain regions in children with new-onset benign childhood epilepsy with centrotemporal spikes (BECTS). Resting-state functional magnetic resonance imaging (fMRI) was performed in 66 children with BECTS and 37 matched control children. We compared the amplitude of low frequency fluctuation (ALFF) signals between the two groups to find the potential epileptogenic zone (EZ), then used Granger causality analysis (GCA) to explore the causal effects of EZ on the whole brain. Children with BECTS had significantly increased ALFF in the right Broca’s area, and decreased ALFF in bilateral fusiform gyrus. The patients also showed increased driving effect from the EZ in Broca’s area to the right prefrontal lobe, and decreased effects to the frontal lobe and posterior parts of the language network. The causal effect on left Wernicke’s area negatively correlated with verbal IQ (VIQ) score. Our research on new-onset BECTS patients illustrates a possible compensatory mechanism in the language network at early stages of BECTS, and the negative correlation of GCA and VIQ suggest the disturbance of epileptiform activity on language. These findings shed light on the mechanisms of and language dysfunction in BECTS.

T60. ADHD and the Cortex: Evidence From Large Clinical and Population Based Samples

Neuroimaging studies show structural alterations of various brain regions in children and adults with ADHD. However, these studies are often underpowered and heterogeneous in their methods. Here, we present data from large-scale clinical and population-based samples to study links between ADHD and the cortex.

Cortical and Subcortical Brain Morphometry Differences Between Patients With Autism Spectrum Disorder and Healthy Individuals Across the Lifespan: Results From the ENIGMA ASD Working Group.

Neuroimaging studies show structural differences in both cortical and subcortical brain regions in children and adults with autism spectrum disorder (ASD) compared with healthy subjects. Findings are inconsistent, however, and it is unclear how differences develop across the lifespan. The authors investigated brain morphometry differences between individuals with ASD and healthy subjects, cross-sectionally across the lifespan, in a large multinational sample from the Enhancing Neuroimaging Genetics Through Meta-Analysis (ENIGMA) ASD working group. The sample comprised 1,571 patients with ASD and 1,651 healthy control subjects (age range, 2-64 years) from 49 participating sites. MRI scans were preprocessed at individual sites with a harmonized protocol based on a validated automated-segmentation software program. Mega-analyses were used to test for case-control differences in subcortical volumes, cortical thickness, and surface area. Development of brain morphometry over the lifespan was modeled using a fractional polynomial approach. The case-control mega-analysis demonstrated that ASD was associated with smaller subcortical volumes of the pallidum, putamen, amygdala, and nucleus accumbens (effect sizes [Cohen's d], 0.13 to -0.13), as well as increased cortical thickness in the frontal cortex and decreased thickness in the temporal cortex (effect sizes, -0.21 to 0.20). Analyses of age effects indicate that the development of cortical thickness is altered in ASD, with the largest differences occurring around adolescence. No age-by-ASD interactions were observed in the subcortical partitions. The ENIGMA ASD working group provides the largest study of brain morphometry differences in ASD to date, using a well-established, validated, publicly available analysis pipeline. ASD patients showed altered morphometry in the cognitive and affective parts of the striatum, frontal cortex, and temporal cortex. Complex developmental trajectories were observed for the different regions, with a developmental peak around adolescence. These findings suggest an interplay in the abnormal development of the striatal, frontal, and temporal regions in ASD across the lifespan.

Subcortical brain volume differences in participants with attention deficit hyperactivity disorder in children and adults: a cross-sectional mega-analysis

Neuroimaging studies have shown structural alterations in several brain regions in children and adults with attention deficit hyperactivity disorder (ADHD). Through the formation of the international ENIGMA ADHD Working Group, we aimed to address weaknesses of previous imaging studies and meta-analyses, namely inadequate sample size and methodological heterogeneity. We aimed to investigate whether there are structural differences in children and adults with ADHD compared with those without this diagnosis. In this cross-sectional mega-analysis, we used the data from the international ENIGMA Working Group collaboration, which in the present analysis was frozen at Feb 8, 2015. Individual sites analysed structural T1-weighted MRI brain scans with harmonised protocols of individuals with ADHD compared with those who do not have this diagnosis. Our primary outcome was to assess case-control differences in subcortical structures and intracranial volume through pooling of all individual data from all cohorts in this collaboration. For this analysis, p values were significant at the false discovery rate corrected threshold of p=0·0156. Our sample comprised 1713 participants with ADHD and 1529 controls from 23 sites with a median age of 14 years (range 4-63 years). The volumes of the accumbens (Cohen's d=-0·15), amygdala (d=-0·19), caudate (d=-0·11), hippocampus (d=-0·11), putamen (d=-0·14), and intracranial volume (d=-0·10) were smaller in individuals with ADHD compared with controls in the mega-analysis. There was no difference in volume size in the pallidum (p=0·95) and thalamus (p=0·39) between people with ADHD and controls. Exploratory lifespan modelling suggested a delay of maturation and a delay of degeneration, as effect sizes were highest in most subgroups of children (<15 years) versus adults (>21 years): in the accumbens (Cohen's d=-0·19 vs -0·10), amygdala (d=-0·18 vs -0·14), caudate (d=-0·13 vs -0·07), hippocampus (d=-0·12 vs -0·06), putamen (d=-0·18 vs -0·08), and intracranial volume (d=-0·14 vs 0·01). There was no difference between children and adults for the pallidum (p=0·79) or thalamus (p=0·89). Case-control differences in adults were non-significant (all p>0·03). Psychostimulant medication use (all p>0·15) or symptom scores (all p>0·02) did not influence results, nor did the presence of comorbid psychiatric disorders (all p>0·5). With the largest dataset to date, we add new knowledge about bilateral amygdala, accumbens, and hippocampus reductions in ADHD. We extend the brain maturation delay theory for ADHD to include subcortical structures and refute medication effects on brain volume suggested by earlier meta-analyses. Lifespan analyses suggest that, in the absence of well powered longitudinal studies, the ENIGMA cross-sectional sample across six decades of ages provides a means to generate hypotheses about lifespan trajectories in brain phenotypes. National Institutes of Health.

Unidentified bright objects in neurofibromatosis type 1: Results of diffusion tensor imaging in children and adolescents

To evaluate by means of diffusion tensor magnetic resonance imaging (DTI) if changes in apparent diffusion coefficient (ADC) and diffusion tensor fraction anisotropy (FA) in unidentified bright objects (UBOs) and perilesional normal appearing brain regions of children with neurofibromatosis type 1 (NF1) can be observed. Ten children with NF1 underwent conventional magnetic resonance imaging and DTI. The ADC and FA in UBOs and perilesional normal appearing brain of NF1 patients were compared with the same regions of the brain of controls. The ADC increased significantly for UBOs and surrounding normal appearing brain tissue of the brain in children with NF1. We observed no significant differences in FA between the UBOs and perilesional areas or that of controls. Although there is limited neuropathologic information about UBOs, detection of diffusion properties of UBOs can be used to understand tissue characteristics of UBOs, noninvasively.