White matter volume and myelin oligodendrocyte glycoprotein (MOG) microsatellites in pediatric obsessive-compulsive disorder

The myelin oligodendrocyte glycoprotein ( MOG ) gene plays an important role in myelination and has been implicated in the genetics of white matter changes in obsessive-compulsive disorder (OCD). We examined the association between variations of two microsatellite markers across MOG for association and total white matter volume as measured using volumetric MRI in 37 pediatric OCD patients 7-18 years. We compared white matter volumes between microsatellite allele groups using analysis of covariance with covariates of age, gender, and total intracranial volume. After controlling for multiple comparisons, a significant relationship was detected between MOG (TAAA)n and increased total white matter volume ( P  = 0.018-0.028). Although preliminary, our findings provide further support for the involvement of MOG in OCD.

Extreme prematurity and perinatal risk factors related to extremely preterm birth are associated with complex patterns of regional brain volume alterations at 10 years of age: a voxel-based morphometry study

Objective

Structural brain volumetric differences have been investigated previously in very preterm children. However, children born extremely preterm, at the border of viability, have been studied to a lesser degree. Our group previously analyzed children born extremely preterm at term using voxel-based morphometry. In this study, we aimed to examine regional gray and white matter differences for children born extremely preterm derived from the same cohort during childhood. We also aimed to explore the effect of perinatal risk factors on brain volumes in the same group.

Methods

At 10 years of age, 51 children born extremely preterm (before 27 weeks and 0 days) and 38 term-born controls with high-quality 3.0 Tesla magnetic resonance images were included. Statistical analyses using voxel-based morphometry were conducted on images that were normalized using age-specific templates, modulated, and smoothed. Analyses were also performed in stratified groups of children born extremely preterm in the absence or presence of perinatal risk factors that have previously been shown to be associated with volumetric differences at term.

Results

We found volumetric decreases in gray and white matter in the temporal lobes, gray matter decreases in the precuneus gyri, and white matter decreases in the anterior cingulum for children born extremely preterm (all p < 0.001, and p_fwe < 0.05). Gray and white matter increases were predominantly observed in the right posterior cingulum and occipital lobe (all p < 0.001, and p_fwe < 0.05). Of the examined perinatal risk factors, intraventricular hemorrhage grades I-II compared with no intraventricular hemorrhage and patent ductus arteriosus ligation compared with no treated patent ductus arteriosus or patent ductus arteriosus treated with ibuprofen led to volumetric differences at 10 years of age (all p < 0.001, and p_fwe < 0.05).

Conclusions

Children born extremely preterm exhibit volumetric alterations in a pattern overlapping that previously found at term, where many regions with differences are the main hubs of higher order networks. Some, but not all, risk factors known to be associated with structural alterations at term were associated with alterations at 10 years of age.

Magnetic Resonance Imaging as a Diagnostic and Research Tool in Patients with Olfactory Dysfunction: A Systematic Review

BACKGROUND

Patients with acquired, idiopathic olfactory dysfunction (OD) commonly undergo magnetic resonance imaging (MRI) evaluation to rule out intracranial pathologies. This practice is highly debated given the expense of MRI relative to the probability of detecting a treatable lesion. This, combined with the increasing use of MRI in research to investigate the mechanisms underlying OD, provided the impetus for this comprehensive review.

OBJECTIVE

The purpose of this systematic review was to both assess the utility of MRI in diagnosis of idiopathic OD and to describe MRI findings among mixed OD etiologies to better understand its role as a research tool in this patient population.

METHODS

A literature search of PubMed, Embase, Cochrane, Web of Science, and Scopus for studies with original MRI data for patients with OD was completed. Studies exclusively investigating patients with neurocognitive deficits or those studying traumatic or congenital etiologies of OD were excluded.

RESULTS

From 1758 candidate articles, 33 studies were included. Four studies reviewed patients with idiopathic OD for structural pathologies on MRI, of which 17 of 372 (4.6%) patients had a potential central cause identified, and 3 (0.8%) had an olfactory meningioma or olfactory neuroblastoma. Fourteen studies (42.4%) reported significant correlation between olfactory bulb volume and olfactory outcomes, and 6 studies (18.8%) reported gray matter volume reduction, specifically in the orbitofrontal cortex, anterior cingulate cortex, insular cortex, parahippocampal, and piriform cortex areas, in patients with mixed OD etiologies. Functional MRI studies reported reduced brain activation and functional connectivity in olfactory network areas.

CONCLUSION

MRI uncommonly detects intracranial pathology in patients with idiopathic OD. Among patients with mixed OD etiologies, reduced olfactory bulb and gray matter volume are the most common abnormal findings on MRI. Further research is required to better understand the role of MRI and its cost-effectiveness in patients with acquired, idiopathic OD.

Altered Brain Morphometry in Cerebral Small Vessel Disease With Cerebral Microbleeds: An Investigation Combining Univariate and Multivariate Pattern Analyses

Purpose

The objective of this study was to evaluate whether altered gray matter volume (GMV) and white matter volume (WMV) are associated with the presence of cerebral microbleeds (CMBs) in cerebral small vessel disease (CSVD).

Materials and Methods

In this study, we included 26 CSVD patients with CMBs (CSVD-c), 43 CSVD patients without CMBs (CSVD-n) and 39 healthy controls. All participants underwent cognitive assessment testing. Both univariate analysis and multivariate pattern analysis (MVPA) approaches were applied to investigate differences in brain morphometry among groups.

Results

In univariate analysis, GMV and WMV differences were compared among groups using voxel-based morphometry (VBM) with diffeomorphic anatomical registration through exponentiated lie algebra (DARTEL). Compared to healthy controls, the CSVD-c group and CSVD-n group showed significantly lower GMV than the control group in similar brain clusters, mainly including the right superior frontal gyrus (medial orbital), left anterior cingulate gyrus, right inferior frontal gyrus (triangular part) and left superior frontal gyrus (medial), while the CSVD-n group also showed significantly lower WMV in the cluster of the left superior frontal gyrus (medial). No significant GMV or WMV differences were found between the CSVD-c group and the CSVD-n group. Specifically, we applied the multiple kernel learning (MKL) technique in MVPA to combine GMV and WMV features, yielding an average of >80% accuracy for three binary classification problems, which was a considerable improvement over the individual modality approach. Consistent with the univariate analysis, the MKL weight maps revealed default mode network and subcortical region damage associated with CSVD compared to controls. On the other hand, when classifying the CSVD-c group and CSVD-n group in the MVPA analysis, we found that some WMVs were highly weighted regions (left olfactory cortex and right middle frontal gyrus), which hinted at the presence of different white matter alterations in the CSVD-c group.

Conclusion

Our findings not only suggested that the localized alterations in GMV and WMV appeared to be associated with the pathophysiology of CSVD but also indicated that altered brain morphometry could be a potential discriminative pattern to detect CSVD at the individual level.

Grey and White Matter Volume Changes after Preterm Birth: A Meta-Analytic Approach

Cross-sectional studies have reported lower brain grey matter volumes (GMV) and white matter volumes (WMV) in preterm (PT) born individuals. While large MRI studies in the normative population have led to a better understanding of brain growth trajectories across the lifespan, such results remain elusive for PT born individuals since large, aggregated datasets of PT born individuals do not exist. To close this gap, we investigated GMV and WMV in PT born individuals as reported in the literature and contrasted it against individual volumetric data and trajectories from the general population. Systematic database search of PubMed and Web of Science in March 2021, and extraction of outcome measures were conducted by two independent reviewers. Individual data on full-term (FT) controls was extracted from freely available databases. Mean GMV, WMV, total intracranial volume (TIV), and mean age at scan were the main outcome measures. Of 532 identified records, nine studies were included with 538 PT born subjects between 1.1 and 28.5 years of age. Reference data was generated from 880 FT controls between 1 and 30 years of age. GMV was consistently lower in PT born individuals from infancy to early adulthood with no evidence for catch-up growth. While GMV changes followed a similar trajectory as FT controls, WMV was particularly low in adolescence after PT birth. Results demonstrate altered brain volumes after PT birth across the first half of lifespan. Future studies should address this issue in large aggregated datasets of PT born individuals.

White Matter Atrophy in Type 2 Diabetes Mellitus Patients With Mild Cognitive Impairment

Type 2 diabetes mellitus (T2DM) patients are highly susceptible to developing dementia, especially for those with mild cognitive impairment (MCI), but its underlying cause is still unclear. In this study, we performed a battery of neuropsychological tests and high-resolution sagittal T1-weighted structural imaging to explore how T2DM affects white matter volume (WMV) and cognition in 30 T2DM-MCI patients, 30 T2DM with normal cognition (T2DM-NC) patients, and 30 age-, sex-, and education-matched healthy control (HC) individuals. The WMV of the whole brain was obtained with automated segmentation methods. Correlations between the WMV of each brain region and neuropsychological tests were analyzed in the T2DM patients. The T2DM-NC patients and HC individuals did not reveal any significant differences in WMV. Compared with the T2DM-NC group, the T2DM-MCI group showed statistically significant reduction in the WMV of seven brain regions, mainly located in the frontotemporal lobe and limbic system, five of which significantly correlated with Montreal Cognitive Assessment (MoCA) scores. Subsequently, we evaluated the discriminative ability of these five regions for MCI in T2DM patients. The WMV of four regions, including left posterior cingulate, precuneus, insula, and right rostral middle frontal gyrus had high diagnostic value for MCI detection in T2DM patients (AUC > 0.7). Among these four regions, left precuneus WMV presented the best diagnostic value (AUC: 0.736; sensitivity: 70.00%; specificity: 73.33%; Youden index: 0.4333), but with no significant difference relative to the minimum AUC. In conclusion, T2DM could give rise to the white matter atrophy of several brain regions. Each WMV of left posterior cingulate, precuneus, insula, and right rostral middle frontal gyrus could be an independent imaging biomarker to detect cognitive impairment at the early stage in T2DM patients and play an important role in its pathophysiological mechanism.

Structural Analysis of Brain Hub Region Volume and Cortical Thickness in Patients with Mild Cognitive Impairment and Dementia

Background and Objectives: A complex network of axonal pathways interlinks the human brain cortex. Brain networks are not distributed evenly, and brain regions making more connections with other parts are defined as brain hubs. Our objective was to analyze brain hub region volume and cortical thickness and determine the association with cognitive assessment scores in patients with mild cognitive impairment (MCI) and dementia. Materials and Methods: In this cross-sectional study, we included 11 patients (5 mild cognitive impairment; 6 dementia). All patients underwent neurological examination, and Montreal Cognitive Assessment (MoCA) test scores were recorded. Scans with a 3T MRI scanner were done, and cortical thickness and volumetric data were acquired using Freesurfer 7.1.0 software. Results: By analyzing differences between the MCI and dementia groups, MCI patients had higher hippocampal volumes (p < 0.05) and left entorhinal cortex thickness (p < 0.05). There was a significant positive correlation between MoCA test scores and left hippocampus volume (r = 0.767, p < 0.01), right hippocampus volume (r = 0.785, p < 0.01), right precuneus cortical thickness (r = 0.648, p < 0.05), left entorhinal cortex thickness (r = 0.767, p < 0.01), and right entorhinal cortex thickness (r = 0.612, p < 0.05). Conclusions: In our study, hippocampal volume and entorhinal cortex showed significant differences in the MCI and dementia patient groups. Additionally, we found a statistically significant positive correlation between MoCA scores, hippocampal volume, entorhinal cortex thickness, and right precuneus. Although other brain hub regions did not show statistically significant differences, there should be additional research to evaluate the brain hub region association with MCI and dementia.

Specific Brain Morphometric Changes in Spinal Cord Injury: A Voxel-Based Meta-Analysis of White and Gray Matter Volume

The objective of the study was to investigate degenerative changes of white matter volume (WMV) and gray matter volume (GMV) in individuals after a spinal cord injury (SCI). Published studies of whole-brain voxel-based morphometry (VBM) published between January 1, 2006 and March 1, 2018 comparing SCI patients with controls were collected by searching PubMed, Web of Science, and EMBASE databases. Voxel-wise meta-analyses of GMV and WMV differences between SCI patients and controls were performed separately using seed-based d mapping. Twelve studies with 12 GMV data sets and 9 WMV data sets yielded a total of 466 individuals (190 SCI patients and 276 controls) who were included in this meta-analysis. Compared with controls, SCI patients showed GMV atrophy in sensorimotor system regions including the bilateral sensorimotor cortex (S1 and M1), the supplementary motor area (SMA), paracentral gyrus, thalamus, and basal ganglia, as well as WMV loss in the corticospinal tract.GMV aberrancies were also demonstrated in brain regions responsible for cognition and emotion, such as the orbitofrontal cortex (OFC) and the left insula. Additionally, GMV in both the bilateral S1 and the left SMA was positively correlated with the time span after the injury. In conclusion, anatomical atrophy in cortical-thalamic-spinal pathways suggested that SCIs may result in degenerative changes of the sensorimotor system. Further, OFC and insula GMV abnormalities may explain symptoms such as neuropathic pain and potential cognitive-emotional impairments in chronic SCI patients. These findings indicate that anatomical brain magnetic resonance imaging (MRI) protocols could be neuroimaging biomarkers for interventional studies and treatments.

Impact of frequency of internet use on development of brain structures and verbal intelligence: Longitudinal analyses

Excessive internet use is shown to be cross sectionally associated with lower cognitive functioning and reduced volume of several brain areas. However, the effects of daily internet use on the development of verbal intelligence and brain structures have not been investigated. Here, we cross sectionally examined the effects of the frequency of internet use on regional gray/white matter volume (rGMV/rWMV) and verbal intelligence as well as their longitudinal changes after 3.0 ± 0.3 (standard deviation) years in a large sample of children recruited from the general population (mean age, 11.2 ± 3.1 years; range, 5.7-18.4 years). Although there were no significant associations in cross sectional analyses, a higher frequency of internet use was found to be associated with decrease of verbal intelligence and smaller increase in rGMV and rWMV of widespread brain areas after a few years in longitudinal analyses. These areas involve areas related to language processing, attention and executive functions, emotion, and reward. In conclusion, frequent internet use is directly or indirectly associated with decrease of verbal intelligence and development to smaller gray matter volume at later stages.

Functional MRI of Human Eyeblink Classical Conditioning in Children with Fetal Alcohol Spectrum Disorders

Prenatal alcohol exposure has been linked to a broad range of developmental deficits, with eyeblink classical conditioning (EBC) among the most sensitive endpoints. This fMRI study compared EBC-related brain activity in 47 children with fetal alcohol syndrome (FAS), partial FAS (PFAS), heavily exposed (HE) non-syndromal children, and healthy controls. All of the children had previously participated in two EBC studies conducted as part of our longitudinal study of fetal alcohol spectrum disorders. Although learning-related behavioral differences were seen in all groups during the scans, controls showed more conditioned responses (CR) than the alcohol-exposed groups. Despite lower conditioning levels relative to controls, the exposed groups exhibited extensive cerebellar activations. Specifically, children with FAS/PFAS showed increased activation of cerebellar lobule VI in session 2, while HE children showed increased activation in session 1. Continuous measures of prenatal alcohol use correlated with learning-related activations in cerebellum and frontal cortices. Only controls showed significant cerebellar activation-CR correlations in the deep nuclei and lateral lobule VI, suggesting that these key regions supporting EBC may be functionally disorganized in alcohol-exposed children. These findings are the first to characterize abnormalities in brain function associated with the behavioral conditioning deficits seen in children with prenatal alcohol exposure.

Cognitive Function and Kidney Disease: Baseline Data From the Systolic Blood Pressure Intervention Trial (SPRINT)

BACKGROUND

Chronic kidney disease is common and is associated with cardiovascular disease, cerebrovascular disease, and cognitive function, although the nature of this relationship remains uncertain.

STUDY DESIGN

Cross-sectional cohort using baseline data from the Systolic Blood Pressure Intervention Trial (SPRINT).

SETTING & PARTICIPANTS

Participants in SPRINT, a randomized clinical trial of blood pressure targets in older community-dwelling adults with cardiovascular disease, chronic kidney disease, or high cardiovascular disease risk and without diabetes or known stroke, who underwent detailed neurocognitive testing in the cognition substudy, SPRINT-Memory and Cognition in Decreased Hypertension (SPRINT-MIND).

PREDICTORS

Urine albumin-creatinine ratio (ACR) and estimated glomerular filtration rate (eGFR).

OUTCOMES

Cognitive function, a priori defined as 5 cognitive domains based on 11 cognitive tests using z scores, and abnormal white matter volume quantified by brain magnetic resonance imaging.

RESULTS

Of 9,361 SPRINT participants, 2,800 participated in SPRINT-MIND and 2,707 had complete data; 637 had brain imaging. Mean age was 68 years, 37% were women, 30% were black, and 20% had known cardiovascular disease. Mean eGFR was 70.8±20.9mL/min/1.73m² and median urine ACR was 9.7 (IQR, 5.7-22.5) mg/g. In adjusted analyses, higher ACR was associated with worse global cognitive function, executive function, memory, and attention, such that each doubling of urine ACR had the same association with cognitive performance as being 7, 10, 6, and 14 months older, respectively. Lower eGFR was independently associated with worse global cognitive function and memory. In adjusted models, higher ACR, but not eGFR, was associated with larger abnormal white matter volume.

LIMITATIONS

Cross-sectional only, no patients with diabetes were included.

CONCLUSIONS

In older adults, higher urine ACR and lower eGFR have independent associations with global cognitive performance with different affected domains. Albuminuria concurrently identifies a higher burden of abnormal brain white matter disease, suggesting that vascular disease may mediate these relationships.

Structural and resting-state MRI detects regional brain differences in young and mid-age healthy APOE-e4 carriers compared with non-APOE-e4 carriers

The presence of the e4 allele of the apolipoprotein E (APOE) gene is the best-known genetic risk factor for Alzheimer's disease. In this study, we investigated the link between functional and behavioural differences and regional brain volume and cortical thickness differences in those who carry the e4 allele (e4+) and those who only carry the e3 allele (e3/e3). We studied these genotype populations in two age groups: a young group (average age, 21 years) and a mid-age group (average age, 50 years). High-resolution T1 -weighted MRI scans were analysed with Freesurfer to measure regional white matter brain volume and cortical thickness differences between genotype groups at each age. These data were correlated with behavioural findings in the same cohort. Resting-state MRI was also conducted to identify differences in underlying brain functional connectivity. We found that there was a positive correlation between the thickness of the parahippocampal cortex in young e4+ individuals and performance on an episodic memory task. Young e4+ individuals also showed a positive correlation between white matter volume in the left anterior cingulate and performance on a covert attention task. At mid-age, e4+ individuals had structural differences relative to e3/e3 individuals in these areas: the parahippocampal cortex was thicker and white matter volume in the left anterior cingulate was greater than in e3/e3 individuals. We discuss the possibility that an over-engagement with these regions by e4+ individuals in youth may have a neurogenic effect that is observable later in life. The cuneus appears to be an important region for APOE-driven differences in the brain, with greater functional connectivity among young e3/e3 individuals and greater white matter volume in young e4+ individuals.

A voxel-based morphometric study of age- and sex-related changes in white matter volume in the normal aging brain

OBJECTIVE

To carry out a cross-sectional study of 187 cognitively normal Chinese adults using the voxel-based morphometry (VBM) approach to delineate age-related changes in the white matter volume of regions of interest in the brain and further analyze their correlation with age.

MATERIALS AND METHODS

A total of 187 cognitively normal adults were divided into the young, middle, and old age-groups. Conventional magnetic resonance imaging was performed with the Achieva 3.0 T system. Structural images were processed using VBM8 and statistical parametric mapping 8. Regions of interest were obtained by WFU PickAtlas, and all realigned images were spatially normalized.

RESULTS

Females showed significantly greater total white matter volume than males (t=2.36, P=0.0096, false-discovery rate [FDR] corrected). VBM demonstrated statistically significant age-related differences in white matter volume between the young age-group and the middle age-group (P<0.05, FDR corrected) and between the middle age-group and the old age-group (P<0.05, FDR corrected). No interaction was found between age and sex on white matter volume (P<0.05, FDR corrected). Logistic regression analysis revealed nonlinear correlation between total white matter volume and age (R (2)=0.124, P<0.001). White matter volume gradually increased before 40 years of age, peaked around 50 years of age, and rapidly declined after 60 years of age.

CONCLUSION

Significant age-related differences are present in white matter volume across multiple brain regions during aging. The VBM approach may help differentiate underlying normal neurobiological aging changes of specific brain regions from neurodegenerative impairments.

Volumetric Brain Morphometry Changes in Patients with Obstructive Sleep Apnea Syndrome: Effects of CPAP Treatment and Literature Review

INTRODUCTION

Obstructive sleep apnea syndrome (OSAS) is a frequent breathing disorder occurring during sleep that is characterized by recurrent hypoxic episodes and sleep fragmentation. It remains unclear whether OSAS leads to structural brain changes, and if so, in which brain regions. Brain region-specific gray and white matter volume (GMV and WMV) changes can be measured with voxel-based morphometry (VBM). The aims of this study were to use VBM to analyze GMV and WMV in untreated OSAS patients compared to healthy controls (HC); examine the impact of OSAS-related variables (nocturnal hypoxemia duration and sleep fragmentation index) on GMV and WMV; and assess the effects of therapeutic vs. sham continuous positive airway pressure (CPAP) treatment. We discuss our results in light of previous findings and provide a comprehensive literature review.

METHODS

Twenty-seven treatment-naïve male patients with moderate to severe OSAS and seven healthy age- and education-matched HC were recruited. After a baseline fMRI scan, patients randomly received either active (therapeutic, n = 14) or sham (subtherapeutic, n = 13) nasal CPAP treatment for 2 months.

RESULTS

Significant negative correlations were observed between nocturnal hypoxemia duration and GMV in bilateral lateral temporal regions. No differences in GMV or WMV were found between OSAS patients and HC, and no differences between CPAP vs. sham CPAP treatment effects in OSAS patients.

CONCLUSION

It appears that considering VBM GMV changes there is little difference between OSAS patients and HC. The largest VBM study to date indicates structural changes in the lateral aspect of the temporal lobe, which also showed a significant negative correlation with nocturnal hypoxemia duration in our study. This finding suggests an association between the effect of nocturnal hypoxemia and decreased GMV in OSAS patients.

Source-based morphometry reveals distinct patterns of aberrant brain volume in delusional infestation

Little is known about the neural correlates of delusional infestation (DI), the delusional belief to be infested with pathogens. So far, evidence comes mainly from case reports and case series. We investigated brain morphology in 16 DI patients and 16 healthy controls using structural magnetic resonance imaging and a multivariate data analysis technique, i.e. source-based morphometry (SBM). In addition, we explored differences in brain structure in patient subgroups based on disease aetiology. SBM revealed two patterns exhibiting significantly (p<0.05, Bonferroni-corrected) lower grey and higher white matter volume in DI patients compared to controls. Lower grey matter volume was found in medial prefrontal cortex, anterior cingulate cortex, medial temporal lobe structures (parahippocampus and hippocampus), sensorimotor cortices, bilateral insula and thalamus and inferior parietal regions. Higher white matter volume was found in medial and middle frontal and temporal cortices, left insula and lentiform nucleus. Grey matter volume was abnormal in both "psychiatric" (primary DI and DI associated with an affective disorder) and "organic" DI (DI due to a medical condition). In contrast, aberrant white matter volume was only confirmed for the "organic" DI patient subgroup. These results suggest prefrontal, temporal, parietal, insular, thalamic and striatal dysfunction underlying DI. Moreover, the data suggest that aetiologically distinct presentations of DI share similar patterns of abnormal grey matter volume, whereas aberrant white matter volume appears to be restricted to organic cases.

Is there an association between peripheral immune markers and structural/functional neuroimaging findings?

OBJECTIVES

There is mounting evidence that inflammatory processes play a key role in emotional as well as cognitive dysfunctions. In this context, research employing magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MR spectroscopy) suggests a possible link between structural/functional anomalies in the brain and an increase of circulating inflammation markers. The present paper reviews this research, with particular focus on major depressive disorder (MDD), cognitive impairment in older adults, Alzheimer's disease (AD) and schizophrenia.

RESULTS

In MDD, cognitive impairment and AD, inflammatory processes have been found to be associated with both structural and functional anomalies, perhaps under the influence of environmental stress. Not enough research can suggest similar considerations in schizophrenia, although studies in mice and non-human primates support the belief that inflammatory responses generated during pregnancy can affect brain development and contribute to the etiology of schizophrenia.

CONCLUSIONS

The present review suggests a link between inflammatory processes and MRI detected anomalies in the brain of individuals with MDD, older adults with cognitive impairment as well as of individuals with AD and schizophrenia.

Correlations between brain structures and study time at home in healthy children: a longitudinal analysis

INTRODUCTION

Like sleeping and eating habits, the study habits adopted by children when they are at home are important contributors to lifestyle and they affect cognitive ability. It has recently been reported that sleeping and eating habits change the brain structure of children. However, no research on the effect of study habits at home on the brain structure of children has been conducted thus far. We investigated the effects of study habits at home on the brain structures of healthy children by examining correlations between study time at home and changes in brain structure over the course of 3 years.

METHODS

We used the brain magnetic resonance images of 229 healthy children aged 5.6-18.4 years and computed the changes (time 2-time 1) in regional gray matter and white matter volume (rWMV) using voxel-based morphometry. Whole-brain multiple regression analysis revealed a significant positive correlation between study time at home and changes in rWMV in the right superior frontal gyrus (SFG). Behaviorally, we found a significant positive correlation between study time at home and change in the verbal comprehension index (VCI), one of the subscales of the Wechsler Intelligence Scale for Children-third edition (WISC-III).

RESULTS AND CONCLUSIONS

Given that the SFG is involved in memory control and that the VCI measures abilities related to vocabulary, our results indicate that greater SFG involvement in the memorization component of longer study times may result in greater increases in the number of axons and more axon branching and myelination, causing plastic changes in the neural network involved in memory processes.

Abnormal gray and white matter volume in delusional infestation

Little is known about the neural basis of delusional infestation (DI), the delusional belief to be infested with pathogens. Case series and the response to anti-dopaminergic medication indicate disruptions in dopaminergic neurotransmission in the striatum (caudate, putamen), but did not allow for population-based inference. Here, we report the first whole-brain structural neuroimaging study to investigate gray and white matter abnormalities in DI compared to controls. In this study, we used structural magnetic resonance imaging and voxel-based morphometry to investigate gray and white matter volume in 16 DI patients and 16 matched healthy controls. Lower gray matter volume in DI patients compared to controls was found in left medial, lateral and right superior frontal cortices, left anterior cingulate cortex, bilateral insula, left thalamus, right striatal areas and in lateral and medial temporal cortical regions (p<0.05, cluster-corrected). Higher white matter volume in DI patients compared to controls was found in right middle cingulate, left frontal opercular and bilateral striatal regions (p<0.05, cluster-corrected). This study shows that structural changes in prefrontal, temporal, insular, cingulate and striatal brain regions are associated with DI, supporting a neurobiological model of disrupted prefrontal control over somato-sensory representations.

White matter development in adolescence: the influence of puberty and implications for affective disorders

There have been rapid advances in understanding a broad range of changes in brain structure and function during adolescence, and a growing interest in identifying which of these neurodevelopmental changes are directly linked with pubertal maturation—at least in part because of their potential to provide insights into the numerous emotional and behavioral health problems that emerge during this developmental period. This review focuses on what is known about the influence of puberty on white matter development in adolescence.We focus on white matter because of its role in providing the structural architectural organization of the brain and as a structural correlate of communication within complex neural systems. We begin with a review of studies that report sex differences or sex by age interactions in white matter development as these findings can provide, although indirectly,information relevant to puberty-related changes. Studies are also critically reviewed based on methodological procedures used to assess pubertal maturation and relations with white matter changes. Findings are discussed in light of their implications for the development of neural systems underlying the regulation of emotion and behavior and how alterations in the development of these systems may mediate risk for affective disorders in vulnerable adolescents.

Diffusion tensor quantification of the relations between microstructural and macrostructural indices of white matter and reading

Few researchers agree about the relationship between fronto-temporo-parietal white matter microstructure and reading skills. Unlike many previous reports, which only measured fractional anisotropy, we have also measured macroscopic volume (regional white matter tract volume) and three microstructural indices (axial, radial, and mean diffusivity) to increase interpretability of our findings. We examined the reading-related skills and white matter structure in 10 adolescents and adults with a history of poor reading and 20 age-matched typical readers. We applied a diffusion tensor imaging atlas-based algorithm to major white matter pathways. The relation of white matter structural indices to reading group, hemisphere, and reading-related skill was analyzed using linear models. White matter microstructural indices were related to performance on a sublexical decoding task, but the relations between particular microstructural indices and sublexical decoding ability and reading group were different for association (i.e., cortical-cortical) and projection (i.e., subcortical-cortical) white matter pathways. Changes in projection pathways were consistent with alterations in white matter organization and axonal size, whereas changes in association pathways were consistent with alternations in pathway complexity. Changes in macrostructure paralleled changes in microstructure. We conclude that the relations between several microstructural indices and factors related to reading ability are different for association and projection pathways.

Functional differentiation of posterior superior temporal sulcus in autism: a functional connectivity magnetic resonance imaging study

BACKGROUND

Socio-communicative impairments are salient features of autism spectrum disorder (ASD). Abnormal development of posterior superior temporal sulcus (pSTS)--a key processing area for language, biological motion, and social context--could play a role in these deficits.

METHODS

Functional connectivity magnetic resonance imaging was used to examine the synchronization of low-frequency blood oxygen level-dependent fluctuations during continuous performance on a visual search task. Twenty-one children and adolescents with ASD and 26 typically developing individuals-matched on age and IQ-participated in the study. Three subregions of pSTS were delineated with a data-driven approach, and differentiation of pSTS was examined by comparing the connectivity of each subregion.

RESULTS

In typically developing individuals, differentiation of networks was positively associated with age and anatomical maturation (cortical thinning in pSTS, greater white matter volume). In the ASD group, differentiation of pSTS connectivity was significantly reduced, and correlations with anatomical measures were weak or absent. Moreover, pSTS differentiation was inversely correlated with autism symptom severity.

CONCLUSIONS

Atypical maturation of pSTS suggests altered trajectories for functional segregation and integration of networks in ASD, potentially related to impaired cognitive and sensorimotor development. Furthermore, our findings provide a novel explanation for atypically increased connectivity in ASD that has been observed in some functional connectivity magnetic resonance imaging studies.

No change to grey and white matter volumes in bipolar I disorder patients

BACKGROUND

Structural brain imaging is assumed to be a key method to elucidate the underlying neuropathology of bipolar disorder. However, magnetic resonance imaging studies using region of interest analysis and voxel-based morphometry (VBM) revealed quite inconsistent findings. Hence, there is no clear evidence so far for core regions of cortical or subcortical structural abnormalities in bipolar disorder. The aim of this study was to investigate grey and white matter volumes in a large sample of patients with bipolar I disorder.

METHODS

Thirty-five patients with bipolar I disorder and 32 healthy controls matched with respect to gender, handedness and education participated in the study. MRI scanning was performed and an optimized VBM analysis was conducted.

RESULTS

We could not observe any significant differences of grey or white matter volumes between patients with bipolar disorder and healthy control subjects. Additional analyses did not reveal significant correlations between grey or white matter volume with number of manic or depressive episodes, duration of illness, existence of psychotic symptoms, and treatment with lithium or antipsychotics.

CONCLUSIONS

With this VBM study we were not able to identify core regions of structural abnormalities in bipolar disorder.

Cortical gray and white matter volume in unmedicated schizotypal and schizophrenia patients

Magnetic resonance imaging (MRI) studies have revealed fronto-temporal cortical gray matter volume reductions in schizophrenia. However, to date studies have not examined whether age- and sex-matched unmedicated schizotypal personality disorder (SPD) patients share some or all of the structural brain-imaging characteristics of schizophrenia patients. We examined cortical gray/white matter volumes in a large sample of unmedicated schizophrenia-spectrum patients (n=79 SPD, n=57 schizophrenia) and 148 healthy controls. MRI images were reoriented to standard position parallel to the anterior-posterior commissure line, segmented into gray and white matter tissue types, and assigned to Brodmann areas (BAs) using a postmortem-histological atlas. Group differences in regional volume of gray and white matter in the BAs were examined with MANOVA. Schizophrenia patients had significantly reduced gray matter volume widely across the cortex but more marked in frontal and temporal lobes. SPD patients had reductions in the same regions but only about half that observed in schizophrenia and sparing in key regions including BA10. In schizophrenia, greater fronto-temporal volume loss was associated with greater negative symptom severity and in SPD, greater interpersonal and cognitive impairment. Overall, our findings suggest that increased prefrontal volume in BA10 and sparing of volume loss in temporal cortex (BAs 22 and 20) may be a protective factor in SPD which reduces vulnerability to psychosis.