A multiparametric analysis of white matter maturation during late childhood and adolescence

White matter development has been well described using diffusion tensor imaging (DTI), but the microstructural processes driving development remain unclear due to methodological limitations. Here, using neurite orientation dispersion and density imaging (NODDI), inhomogeneous magnetization transfer (ihMT), and multicomponent driven equilibrium single‐pulse observation of T1/T2 (mcDESPOT), we describe white matter development at the microstructural level in a longitudinal cohort of healthy 6–15 year olds. We evaluated age and gender‐related trends in fractional anisotropy (FA), mean diffusivity (MD), neurite density index (NDI), orientation dispersion index (ODI), quantitative ihMT (qihMT), myelin volume fraction (VF_m), and g‐ratio. We found age‐related increases of VF_m in most regions, showing ongoing myelination in vivo during late childhood and adolescence for the first time. No relationship was observed between qihMT and age, suggesting myelin volume increases are driven by increased water content. Age‐related increases were observed for NDI, suggesting axonal packing is also occurring during this time. g‐ratio decreased with age in the uncinate fasciculus, implying changes in communication efficiency are ongoing in this region. FA increased and MD decreased with age in most regions. Gender effects were present in the left cingulum for FA, and an age‐by‐gender interaction was found for MD in the left uncinate fasciculus. These findings suggest that FA and MD remain useful markers of gender‐related processes, and gender differences are likely driven by factors other than myelin. We conclude that white matter development during late childhood and adolescence is driven by a combination of axonal packing and myelin volume increases.     

Association between white matter microstructure,executive functions,and processing speed in older adults: The impact of vascular health

Cerebral white matter damage is not only a commonly reported consequence of healthy aging, but is also associated with cognitive decline and dementia. The aetiology of this damage is unclear; however, individuals with hypertension have a greater burden of white matter signal abnormalities (WMSA) on MR imaging than those without hypertension. It is therefore possible that elevated blood pressure (BP) impacts white matter tissue structure which in turn has a negative impact on cognition. However, little information exists about whether vascular health indexed by BP mediates the relationship between cognition and white matter tissue structure. We used diffusion tensor imaging to examine the impact of vascular health on regional associations between white matter integrity and cognition in healthy older adults spanning the normotensive to moderate–severe hypertensive BP range (43–87 years; N = 128). We examined how white matter structure was associated with performance on tests of two cognitive domains, executive functioning (EF) and processing speed (PS), and how patterns of regional associations were modified by BP and WMSA. Multiple linear regression and structural equation models demonstrated associations between tissue structure, EF and PS in frontal, temporal, parietal, and occipital white matter regions. Radial diffusivity was more prominently associated with performance than axial diffusivity. BP only minimally influenced the relationship between white matter integrity, EF and PS. However, WMSA volume had a major impact on neurocognitive associations. This suggests that, although BP and WMSA are causally related, these differential metrics of vascular health may act via independent pathways to influence brain structure, EF and PS. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc.     

Construction of a stereotaxic DTI atlas with full diffusion tensor information for studying white matter maturation from childhood to adolescence using tractography‐based segmentations

Reconstruction of white matter (WM) fiber tracts based on diffusion tensor imaging (DTI) is increasingly being used in clinical and research settings to study normal and pathological WM tissue as well as the maturation of this WM tissue. Such fiber tracking (FT) methodology, however, is highly dependent on the manual delineation of anatomical landmarks and the algorithm settings, often rendering the reproducibility and reliability questionable. Predefining these regions of interest on a fractional anisotropy (FA) atlas in standard space has already been shown to improve the reliability of FT results. In this paper, we constructed a new DTI atlas, which contains the complete diffusion tensor information in ICBM152 coordinates. From this high‐dimensional DTI atlas, and using robust FT protocols, we reconstructed a large number of WM tracts. Subsequently, we created tract masks from these fiber tract bundles and evaluated the atlas framework by comparing the reproducibility of the results obtained from our standardized tract masks with regions‐of‐interest labels from the conventional FA‐based WM atlas. Finally, we assessed laterality and age‐related WM changes in 42 normal subjects aged 0 to 18 years using these tractography‐derived tract segmentations. In agreement with previous literature, we observed an FA increase with age, which was mainly due to the decrease of perpendicular diffusivity. In addition, major functional pathways in the language, motor, and limbic system, showed a significant asymmetry in terms of the observed diffusion metrics. Hum Brain Mapp, 2010. © 2009 Wiley‐Liss, Inc.     

Cognitive functions correlate with white matter architecture in a normal pediatric population: a diffusion tensor MRI study

A possible relationship between cognitive abilities and white matter structure as assessed by magnetic resonance diffusion tensor imaging (DTI) was investigated in the pediatric population. DTI was performed on 47 normal children ages 5-18. Using a voxelwise analysis technique, the fractional anisotropy (FA) and mean diffusivity (MD) were tested for significant correlations with Wechsler full-scale IQ scores, with subject age and gender used as covariates. Regions displaying significant positive correlations of IQ scores with FA were found bilaterally in white matter association areas, including frontal and occipito-parietal areas. No regions were found exhibiting correlations of IQ with MD except for one frontal area significantly overlapping a region containing a significant correlation with FA. The positive direction of the correlation with FA is the same as that found previously with age, and indicates a positive relationship between fiber organization and/or density with cognitive function. The results are consistent with the hypothesis that regionally specific increased fiber organization is a mechanism responsible for the normal development of white matter tracts.     

Development of superficial white matter and its structural interplay with cortical gray matter in children and adolescents

Healthy human brain undergoes significant changes during development. The developmental trajectory of superficial white matter (SWM) is less understood relative to cortical gray matter (GM) and deep white matter. In this study, a multimodal imaging strategy was applied to vertexwise map SWM microstructure and cortical thickness to characterize their developmental pattern and elucidate SWM‐GM associations in children and adolescents. Microscopic changes in SWM were evaluated with water diffusion parameters including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) in 133 healthy subjects aged 10–18 years. Results demonstrated distinct maturational patterns in SWM and GM. SWM showed increasing FA and decreasing MD and RD underneath bilateral motor sensory cortices and superior temporal auditory cortex, suggesting increasing myelination. A second developmental pattern in SWM was increasing FA and AD in bilateral orbitofrontal regions and insula, suggesting improved axonal coherence. These SWM patterns diverge from the more widespread GM maturation, suggesting that cortical thickness changes in adolescence are not explained by the encroachment of SWM myelin into the GM‐WM boundary. Interestingly, age‐independent intrinsic association between SWM and cortical GM seems to follow functional organization of polymodal and unimodal brain regions. Unimodal sensory areas showed positive correlation between GM thickness and FA whereas polymodal regions showed negative correlation. Axonal coherence and differences in interstitial neuron composition between unimodal and polymodal regions may account for these SWM‐GM association patterns. Intrinsic SWM‐GM relationships unveiled by neuroimaging in vivo can be useful for examining psychiatric disorders with known WM/GM disturbances. Hum Brain Mapp 35:2806–2816, 2014. © 2013 Wiley Periodicals, Inc .     

Intellectual abilities and white matter microstructure in development: A diffusion tensor imaging study

Higher‐order cognitive functions are supported by distributed networks of multiple interconnected cortical and subcortical regions. Efficient cognitive processing depends on fast communication between these regions, so the integrity of the connections between them is of great importance. It is known that white matter (WM) development is a slow process, continuing into adulthood. While the significance of cortical maturation for intellectual development is described, less is known about the relationships between cognitive functions and maturation of WM connectivity. In this cross‐sectional study, we investigated the associations between intellectual abilities and development of diffusion tensor imaging (DTI) derived measures of WM microstructure in 168 right‐handed participants aged 8–30 years. Independently of age and sex, both verbal and performance abilities were positively related to fractional anisotropy (FA) and negatively related to mean diffusivity (MD) and radial diffusivity (RD), predominantly in the left hemisphere. Further, verbal, but not performance abilities, were associated with developmental differences in DTI indices in widespread regions in both hemispheres. Regional analyses showed relations with both FA and RD bilaterally in the anterior thalamic radiation and the cortico‐spinal tract and in the right superior longitudinal fasciculus. In these regions, our results suggest that participants with high verbal abilities may show accelerated WM development in late childhood and a subsequent earlier developmental plateau, in contrast to a steadier and prolonged development in participants with average verbal abilities. Longitudinal data are needed to validate these interpretations. The results provide insight into the neurobiological underpinnings of intellectual development. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.     

White matter structure in autism: preliminary evidence from diffusion tensor imaging.

BACKGROUND: Individuals with autism have severe difficulties in social communication and relationships. Prior studies have suggested that abnormal connections between brain regions important for social cognition may contribute to the social deficits seen in autism. METHODS: In this study, we used diffusion tensor imaging to investigate white matter structure in seven male children and adolescents with autism and nine age-, gender-, and IQ-matched control subjects. RESULTS: Reduced fractional anisotropy (FA) values were observed in white matter adjacent to the ventromedial prefrontal cortices and in the anterior cingulate gyri as well as in the temporoparietal junctions. Additional clusters of reduced FA values were seen adjacent to the superior temporal sulcus bilaterally, in the temporal lobes approaching the amygdala bilaterally, in occipitotemporal tracts, and in the corpus callosum. CONCLUSIONS: Disruption of white matter tracts between regions implicated in social functioning may contribute to impaired social cognition in autism.     

In vivo characterization of emerging white matter microstructure in the fetal brain in the third trimester

The third trimester of pregnancy is a period of rapid development of fiber bundles in the fetal white matter. Using a recently developed motion‐tracked slice‐to‐volume registration (MT‐SVR) method, we aimed to quantify tract‐specific developmental changes in apparent diffusion coefficient (ADC), fractional anisotropy (FA), and volume in third trimester healthy fetuses. To this end, we reconstructed diffusion tensor images from motion corrected fetal diffusion magnetic resonance imaging data. With an approved protocol, fetal MRI exams were performed on healthy pregnant women at 3 Tesla and included multiple (2–8) diffusion scans of the fetal head (1–2 b = 0 s/mm² images and 12 diffusion‐sensitized images at b = 500 s/mm²). Diffusion data from 32 fetuses (13 females) with median gestational age (GA) of 33 weeks 4 days were processed with MT‐SVR and deterministic tractography seeded by regions of interest corresponding to 12 major fiber tracts. Multivariable regression analysis was used to evaluate the association of GA with volume, FA, and ADC for each tract. For all tracts, the volume and FA increased, and the ADC decreased with GA. Associations reached statistical significance for: FA and ADC of the forceps major; volume and ADC for the forceps minor; FA, ADC, and volume for the cingulum; ADC, FA, and volume for the uncinate fasciculi; ADC of the inferior fronto‐occipital fasciculi, ADC of the inferior longitudinal fasciculi; and FA and ADC for the corticospinal tracts. These quantitative results demonstrate the complex pattern and rates of tract‐specific, GA‐related microstructural changes of the developing white matter in human fetal brain.     

Associations between T1 white matter lesion volume and regional white matter microstructure in aging

White matter lesions, typically manifesting as regions of signal intensity abnormality (WMSA) on MRI, increase in frequency with age. However, the role of this damage in cognitive decline and disease is still not clear, as lesion volume has only loosely been associated with clinical status. Diffusion tensor imaging (DTI) has been used to examine the quantitative microstructural integrity of white matter, and has applications in the examination of subtle changes to tissue that appear visually normal on conventional imaging. The primary goal of this study was to determine whether major macrostructural white matter damage, (total WMSA volume), is associated with microstructural integrity of normal appearing white matter, and if these macrostructural changes fully account for microstructural changes. Imaging was performed in 126 nondemented individuals, ages 43–85 years, with no history of cerebrovascular disease. Controlling for age, greater WMSA volume was associated with decreased fractional anisotropy (FA) in widespread brain regions. Patterns were similar for FA and radial diffusivity but in contrast, WMSA was associated with axial diffusivity in fewer areas. Age was associated with FA in several regions, and many of these effects remained even when controlling for WMSA volume, suggesting the etiology of WMSAs does not fully account for all age‐associated white matter deterioration. These results provide evidence that WMSA volume is associated with the integrity of normal‐appearing white matter. In addition, our results suggest that overt lesions may not account for the association of increasing age with decreased white matter tissue integrity. Hum Brain Mapp 35:1085–1100, 2014. © 2013 Wiley Periodicals, Inc.     

Twin–singleton developmental study of brain white matter anatomy

Twin studies provide valuable insights into the analysis of genetic and environmental factors influencing human brain development. However, these findings may not generalize to singletons due to differences in pre‐ and postnatal environments. One would expect the effect of these differences to be greater during the early years of life. To address this concern, we compare longitudinal diffusion data of white matter regions for 26 singletons and 76 twins (monozygotic and dizygotic) from birth to 2 years of age. We use nonlinear mixed effect modeling where the temporal changes in the diffusion parameters are described by the Gompertz function. The Gompertz function describes growth trajectory in terms of intuitive parameters: asymptote, delay, and speed. We analyzed fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD) for 21 regions of interest (ROIs). These ROIs included areas in the association, projection, and commissural fiber tracts. We did not find any differences in the diffusion parameters between monozygotic and dizygotic twins. In addition, FA and RD showed no developmental differences between singletons and twins for the regions analyzed. However, the delay parameter of the Gompertz function of AD for the anterior limb of the internal capsule and anterior corona radiata was significantly different between singletons and twins. Further analysis indicated that the differences are small, and twins “catch up” by the first few months of life. These results suggest that the effects of differences of pre‐ and postnatal environments between twins and singletons are minimal on white matter development and disappear early in life. Hum Brain Mapp 38:1009–1024, 2017. © 2016 Wiley Periodicals, Inc.     

A systematic review of diffusion weighted MRI studies of white matter microstructure in adolescent substance users

Recent studies using diffusion weighted magnetic resonance imaging (DW-MRI) have provided evidence of abnormal white matter microstructure in adults with substance use disorders (SUDs). While there is a growing body of research using DW-MRI to examine the impact of heavy substance use during adolescence, this literature has not been systematically reviewed. Online databases were searched for DW-MRI studies of adolescent substance users, and 10 studies fulfilled the inclusion and exclusion criteria. We identified consistent evidence for abnormal white matter microstructure in neocortical association pathways as well as in projection and thalamic pathways. Dose-dependent relationships between DW-MRI measures and patterns of substance use were also observed. The consistency of these findings with DW-MRI research in adults suggests that white matter microstructure is impacted in the early stages of heavy substance use. However, given the largely cross-sectional nature of the available data, important questions remain regarding the extent to which white matter abnormalities are a consequence of adolescent exposure to alcohol and other drugs of abuse or reflect pre-existing differences that increase risk for SUDs.     

White matter abnormalities observed in bipolar disorder: a diffusion tensor imaging study

OBJECTIVES: An increased incidence in white matter abnormalities is among the most frequently reported brain change in patients with bipolar disorder. The objective of the present study was to examine white matter tract integrity, using diffusion tensor imaging (DTI), in bipolar patients and healthy comparison subjects. METHODS: Eleven DSM-IV bipolar I patients and 10 healthy age- and sex-matched controls were studied. DTI data were acquired on a 1.5 Tesla scanner. Fractional anisotropy (FA) and diffusivity (trace) were determined from axial images using region of interest (ROI) analyses. The ROIs were manually placed in the midline and forward projecting arms of the genu (anterior) and the midline of the splenium (posterior) of the corpus callosum. RESULTS: Bipolar patients had significantly higher FA in the midline of the genu compared with healthy controls. Regional white matter differences were also observed, with significantly lower FA in the genu than forward projecting regions in both groups and lower FA in the genu than the splenium in controls. CONCLUSIONS: Diffusion tensor imaging revealed significant microstructural differences in the genu, as measured by elevated FA in bipolar patients compared with healthy controls. These preliminary findings further support the hypothesis that anomalous frontal brain mechanisms may be associated with bipolar disorder.     

Joint contributions of cortical morphometry and white matter microstructure in healthy brain aging: A partial least squares correlation analysis

Cortical atrophy and degraded axonal health have been shown to coincide during normal aging; however, few studies have examined these measures together. To lend insight into both the regional specificity and the relative timecourse of structural degradation of these tissue compartments across the adult lifespan, we analyzed gray matter (GM) morphometry (cortical thickness, surface area, volume) and estimates of white matter (WM) microstructure (fractional anisotropy, mean diffusivity) using traditional univariate and more robust multivariate techniques to examine age associations in 186 healthy adults aged 20–94 years old. Univariate analysis of each tissue type revealed that negative age associations were largest in frontal GM and WM tissue and weaker in temporal, cingulate, and occipital regions, representative of not only an anterior‐to‐posterior gradient, but also a medial‐to‐lateral gradient. Multivariate partial least squares correlation (PLSC) found the greatest covariance between GM and WM was driven by the relationship between WM metrics in the anterior corpus callosum and projections of the genu, anterior cingulum, and fornix; and with GM thickness in parietal and frontal regions. Surface area was far less susceptible to age effects and displayed less covariance with WM metrics, while regional volume covariance patterns largely mirrored those of cortical thickness. Results support a retrogenesis‐like model of aging, revealing a coupled relationship between frontal and parietal GM and the underlying WM, which evidence the most protracted development and the most vulnerability during healthy aging.     

The joint effect of aging and HIV infection on microstructure of white matter bundles

Recent evidence suggests the aging process is accelerated by HIV. Degradation of white matter (WM) has been independently associated with HIV and healthy aging. Thus, WM may be vulnerable to joint effects of HIV and aging. Diffusion‐weighted imaging (DWI) was conducted with HIV‐seropositive (n = 72) and HIV‐seronegative (n = 34) adults. DWI data underwent tractography, which was parcellated into 18 WM tracts of interest (TOIs). Functional Analysis of Diffusion Tensor Tract Statistics (FADTTS) regression was conducted assessing the joint effect of advanced age and HIV on fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) along TOI fibers. In addition to main effects of age and HIV on WM microstructure, the interactive effect of age and HIV was significantly related to lower FA and higher MD, AD, and RD across all TOIs. The location of findings was consistent with the clinical presentation of HIV‐associated neurocognitive disorders. While older age is related to poorer WM microstructure, its detrimental effect on WM is stronger among HIV+ relative to HIV? individuals. Loss of WM integrity in the context of advancing age may place HIV+ individuals at increased risk for brain and cognitive compromise.     

Fibre orientation atlas guided rapid segmentation of white matter tracts

Fibre tract delineation from diffusion magnetic resonance imaging (MRI) is a valuable clinical tool for neurosurgical planning and navigation, as well as in research neuroimaging pipelines. Several popular methods are used for this task, each with different strengths and weaknesses making them more or less suited to different contexts. For neurosurgical imaging, priorities include ease of use, computational efficiency, robustness to pathology and ability to generalise to new tracts of interest. Many existing methods use streamline tractography, which may require expert neuroimaging operators for setting parameters and delineating anatomical regions of interest, or suffer from as a lack of generalisability to clinical scans involving deforming tumours and other pathologies. More recently, data-driven approaches including deep-learning segmentation models and streamline clustering methods have improved reproducibility and automation, although they can require large amounts of training data and/or computationally intensive image processing at the point of application. We describe an atlas-based direct tract mapping technique called ‘tractfinder’, utilising tract-specific location and orientation priors. Our aim was to develop a clinically practical method avoiding streamline tractography at the point of application while utilising prior anatomical knowledge derived from only 10–20 training samples. Requiring few training samples allows emphasis to be placed on producing high quality, neuro-anatomically accurate training data, and enables rapid adaptation to new tracts of interest. Avoiding streamline tractography at the point of application reduces computational time, false positives and vulnerabilities to pathology such as tumour deformations or oedema. Carefully filtered training streamlines and track orientation distribution mapping are used to construct tract specific orientation and spatial probability atlases in standard space. Atlases are then transformed to target subject space using affine registration and compared with the subject's voxel-wise fibre orientation distribution data using a mathematical measure of distribution overlap, resulting in a map of the tract's likely spatial distribution. This work includes extensive performance evaluation and comparison with benchmark techniques, including streamline tractography and the deep-learning method TractSeg, in two publicly available healthy diffusion MRI datasets (from TractoInferno and the Human Connectome Project) in addition to a clinical dataset comprising paediatric and adult brain tumour scans. Tract segmentation results display high agreement with established techniques while requiring less than 3 min on average when applied to a new subject. Results also display higher robustness than compared methods when faced with clinical scans featuring brain tumours and resections. As well as describing and evaluating a novel proposed tract delineation technique, this work continues the discussion on the challenges surrounding the white matter segmentation task, including issues of anatomical definitions and the use of quantitative segmentation comparison metrics.     

White matter disorders with autosomal dominant heredity: a review with personal clinical case studies and their MRI findings

Sundal C, Ekholm S, Andersen O. White matter disorders with autosomal dominant heredity: a review with personal clinical case studies and their MRI findings.
Acta Neurol Scand: 2010: 121: 328–337.
© 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Background – Leukoencephalopathies are a heterogeneous group of severe encephalopathy syndromes with myelin, axonal or vascular pathology, typically with extensive white matter lesions on MRI T2‐FSE and/or ‐FLAIR sequences. Objectives – This review is restricted to leukoencephalopathies with onset in adult age and a dominant inheritance. These diseases are generally severe and often lethal and present with an exacerbating or insidiously progressive course. Material and methods – The focus is on four syndromes with pure leukoencephalopathies, however, leukoencephalopathies with associated clinical features are included. Results – T2 weighted MR imaging often show features common for leukoencephalopathies, yet shows distinguishing features in transthyretin amyloidosis. Conclusion – The diagnosis within the group of leukoencephalopathies thus characterized by MRI relies mainly upon clinical and genetic analysis. The differential diagnosis against treatable leukoencephalopathies is increasingly relevant.     

抑郁症患者脑白质变化初步研究

目的：利用能够提示脑白质纤维完整性的磁共振弥散张量成像（DTI）探讨首发和复发重性抑郁症患者脑白质纤维的变化及其差异。方法：20例重性抑郁症患者（首发9例，复发11例）和20名正常对照者均经常规磁共振成像（MRI）平扫，未发现异常者继续进行DTI和结构MRI（3D）扫描，基于像素的全脑分析技术对DTI数据进行分析。结果：与对照组相比较，抑郁症组白质纤维结构在双侧额中回、右顶下小叶及双侧脑岛等区域白质的各向异性值（FA）显著降低（各脑区P均〈0.001，cluster〉30像素）;与首发抑郁症患者相比较，复发抑郁症患者右侧额上回、右顶叶、中央前回、中央后回及右顶下小叶等区域FA值降低更为显著（各脑区P均〈0.001，cluster〉10像素）。结论：重性抑郁症患者存在脑白质异常，抑郁反复发作会导致脑白质损害进一步加重。     

Frontal white matter microstructure, aggression, and impulsivity in men with schizophrenia: a preliminary study.

BACKGROUND: Aggression and impulsivity may involve altered frontal white matter. METHODS: Axial diffusion tensor images were acquired in 14 men with schizophrenia using a pulsed gradient, double spin echo, echo planar imaging method. White matter microstructural measures (fractional anisotropy and trace) were calculated from these data. Regions of interest were placed in frontal white matter on four slices. Impulsivity was measured using the Motor Impulsiveness factor of the Barratt Impulsiveness Scale. Aggressiveness was measured using the Assaultiveness scale of the Buss Durkee Hostility Inventory and the Aggression scale of the Life History of Aggression. RESULTS: Lower fractional anisotropy in right inferior frontal white matter was associated with higher motor impulsiveness. Higher trace in these regions was associated with aggressiveness. CONCLUSIONS: Inferior frontal white matter microstructure was associated with impulsivity and aggression in men with schizophrenia. These results implicate frontal lobe dysfunction in aggression and certain aspects of impulsivity.     

Prospective associations,longitudinal patterns of childhood socioeconomic status,and white matter organization in adulthood

The association between childhood socioeconomic status (SES) and brain development is an emerging area of research. The primary focus to date has been on SES and variations in gray matter structure with much less known about the relation between childhood SES and white matter structure. Using a longitudinal study of SES, with measures of income‐to‐needs ratio (INR) at age 9, 13, 17, and 24, we examined the prospective relationship between childhood SES (age 9 INR) and white matter organization in adulthood using diffusion tensor imaging. We also examined how changes in INR from childhood through young adulthood are associated with white matter organization in adult using a latent growth mixture model. Using tract‐based spatial statistics (TBSS) we found that there is a significant prospective positive association between childhood INR and white matter organization in the bilateral uncinate fasciculus, bilateral cingulum bundle, bilateral superior longitudinal fasciculus, and corpus callosum (p < .05, FWE corrected). The probability that an individual was in the high‐increasing INR profile across development compared with the low‐increasing INR profile was positively associated with white matter organization in the bilateral uncinate fasciculus, left cingulum, and bilateral superior longitudinal fasciculus. The results of the current study have potential implications for interventions given that early childhood poverty may have long‐lasting associations with white matter structure. Furthermore, trajectories of socioeconomic status during childhood are important—with individuals that belong to the latent profile that had high increases in INR having greater regional white matter organization in adulthood.