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Tractography methods demonstrated for major cerebral white matter tracts, displayed within the left hemisphere. Tracts are displayed on mid-sagittal T1 images from a representative full term subject. Right hemisphere tract renderings not shown. Panel a illustrates all five tracts: Anterior Superior Longitudinal Fasciculus (aSLF) in yellow, Arcuate Fasciculus (Arc) in red, and Uncinate Fasciculus (UF) in green, Corticospinal Tract (CST) in blue, Inferior Longitudinal Fasciculus (ILF) in purple. Panels b and c include dashed lines to represent the location of the regions of interest (ROIs) used to isolate each cerebral tract; ROI 1, white; ROI 2, black. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)
Source publication
Diffusion properties of white matter tracts have been associated with individual differences in reading. Individuals born preterm are at risk of injury to white matter. In this study we compared the associations between diffusion properties of white matter and reading skills in children and adolescents born full term and preterm. 45 participants, a...
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High angular resolution diffusion imaging (HARDI)-based tractography has been increasingly used in longitudinal studies on white matter macro- and micro-structural changes in the language network during language acquisition and in language impairments. However, test-retest reliability measurements are essential to ascertain that the longitudinal va...
Citations
... Moreover, preterm participants exhibited specific macrostructural, but not microstructural, white-matter abnormalities linked to reading skills and cognitive deficits. Travis et al. (2016;n = 45) also reported differences in the relationships between reading performance and fascicular microstructure in PT vs. FT children. Significant group differences were detected in mean FA for the right anterior SLF and the left arcuate fasciculus (AF), but not in their homologues in the CS tract, uncinate fasciculus or inferior longitudinal fasciculus (ILF). ...
... Specific alterations of neurodevelopmental trajectories were found in PT children, as evidenced by differential associations between white matter properties and task performance between PT and FT participants (Travis et al., 2016;Bruckert et al., 2019;Thompson et al., 2020). Thompson et al. (2020), for example, reported a negative association between reading achievement and connectivity in tracts linking the left caudate and putamen with the lateral prefrontal cortex among FT controls, but not among PT participants. ...
... These results were extended by Kelly et al. (2016) and Collins et al. (2021), who linked CC maturation rate, fiber density, and fiber-bundle cross-section to mathematics achievement and broader cognitive abilities. Finally, differences in the relationships between white matter properties and cognitive and academic performance between PT and FT participants (Travis et al., 2016;Bruckert et al., 2019;Thompson et al., 2020) indicate altered neurodevelopmental trajectories in PT children, pointing to potentially compensatory neurodevelopmental processes. Such findings may support the hypothesis that neurodevelopmental insults from early life adversity, such as preterm birth, can trigger neural plasticity, leading to the recruitment of alternative neural pathways (Johnson and Marlow, 2017). ...
Introduction and methods
In this PRISMA-compliant systematic review, we identify and synthesize the findings of research in which neuroimaging and assessments of achievement have been used to examine the relationships among aspects of developmental programming, neurodevelopment, and achievement in reading and mathematics.
Results
Forty-seven studies met inclusion criteria. The majority examined the impact of prematurity ( n = 32) and prenatal alcohol exposure ( n = 13). Several prematurity studies reported a positive correlation between white-matter integrity of callosal fibers and executive functioning and/or achievement, and white matter properties were consistently associated with cognitive and academic performance in preterm and full-term children. Volumetric studies reported positive associations between academic and cognitive abilities and white and gray matter volume in regions such as the insula, putamen, and prefrontal lobes. Functional MRI studies demonstrated increased right-hemispheric language processing among preterm children. Altered activation of the frontoparietal network related to numerical abilities was also reported. Prenatal alcohol exposure studies reported alterations in white matter microstructure linked to deficits in cognitive functioning and academic achievement, including mathematics, reading, and vocabulary skills. Volumetric studies reported reductions in cerebral, cerebellar, and subcortical gray matter volumes associated with decreased scores on measures of executive functioning, attention, working memory, and academic performance. Functional MRI studies demonstrated broad, diffuse activation, reduced activation in canonical regions, and increased activation in non-canonical regions during numeric tasks.
Discussion
A preponderance of studies linked prematurity and prenatal alcohol exposure to altered neurodevelopmental processes and suboptimal academic achievement. Limitations and recommendations for future research are discussed.
Systematic review registration
Identifier: DOI 10.17605/OSF.IO/ZAN67 .
... Recent studies have used cranial ultrasonography (CUS) and magnetic resonance imaging (MRI) to characterize the anatomical underpinnings of language impairments in full-term and preterm neonates. Several MRI studies based on diffusion tensor imaging (DTI) observed that microstructural changes in cerebral white matter at the school-aged period were associated with language impairments in preterm and full term birth (Travis et al., 2016;Dodson et al., 2018). Greater increases in axonal diffusivity of the left posterior thalamic radiation from term-equivalent postmenstrual age to age 4 years was associated with poorer receptive and expressive language ability at age four (Young et al., 2017). ...
Introduction
Infants born very early preterm are at high risk of language delays. However, less is known about the consequences of late prematurity. Hence, the aim of the present study is to characterize the neural encoding of speech sounds in late preterm neonates in comparison with those born at term.
Methods
The speech-evoked frequency-following response (FFR) was recorded to a consonant-vowel stimulus /da/ in 36 neonates in three different groups: 12 preterm neonates [mean gestational age (GA) 36.05 weeks], 12 “early term neonates” (mean GA 38.3 weeks), and “late term neonates” (mean GA 41.01 weeks).
Results
From the FFR recordings, a delayed neural response and a weaker stimulus F0 encoding in premature neonates compared to neonates born at term was observed. No differences in the response time onset nor in stimulus F0 encoding were observed between the two groups of neonates born at term. No differences between the three groups were observed in the neural encoding of the stimulus temporal fine structure.
Discussion
These results highlight alterations in the neural encoding of speech sounds related to prematurity, which were present for the stimulus F0 but not for its temporal fine structure.
... It is important to take into account here that FA is influenced by a multitude of physiological properties (e.g., crossing fibers, axon density, myelin density). Thus, for VPT born children who may have experienced brain injury and white matter dysmaturity, the processes driving white matter changes may be different as compared to the FT group (Loe et al., 2013;Travis et al., 2016). Variation in FA in these segments could represent different physiological processes or balances for the VPT and FT group (Feldman et al., 2012a;Feldman et al., 2012b;Travis et al., 2016). ...
... Thus, for VPT born children who may have experienced brain injury and white matter dysmaturity, the processes driving white matter changes may be different as compared to the FT group (Loe et al., 2013;Travis et al., 2016). Variation in FA in these segments could represent different physiological processes or balances for the VPT and FT group (Feldman et al., 2012a;Feldman et al., 2012b;Travis et al., 2016). Thus, different physiological properties or a different balance between them (Travis et al., 2016) could be associated with social responsivity. ...
... Variation in FA in these segments could represent different physiological processes or balances for the VPT and FT group (Feldman et al., 2012a;Feldman et al., 2012b;Travis et al., 2016). Thus, different physiological properties or a different balance between them (Travis et al., 2016) could be associated with social responsivity. Nonetheless, showing relations between white matter microstructure and measures of socio-emotional development yields promise for predicting atypical (social-emotional) development or psychiatric conditions from connectivity metrics such as tractometry (Chamberland et al., 2021;Kanel et al., 2021;Neher et al., 2024), eventually creating possibilities for interventions. ...
Children born very preterm (VPT, < 32 weeks of gestation) have an increased risk of developing socio-emotional difficulties. Possible neural substrates for these socio-emotional difficulties are alterations in the structural connectivity of the social brain due to premature birth. The objective of the current study was to study microstructural white matter integrity in VPT versus full-term (FT) born school-aged children along twelve white matter tracts involved in socio-emotional processing. Diffusion MRI scans were obtained from a sample of 35 VPT and 38 FT 8-to-12-year-old children. Tractography was performed using TractSeg, a state-of-the-art neural network-based approach, which offers investigation of detailed tract profiles of fractional anisotropy (FA). Group differences in FA along the tracts were investigated using both a traditional and complementary functional data analysis approach. Exploratory correlations were performed between the Social Responsiveness Scale (SRS-2), a parent-report questionnaire assessing difficulties in social functioning, and FA along the tract. Both analyses showed significant reductions in FA for the VPT group along the middle portion of the right SLF I and an anterior portion of the left SLF II. These group differences possibly indicate altered white matter maturation due to premature birth and may contribute to altered functional connectivity in the Theory of Mind network which has been documented in earlier work with VPT samples. Apart from reduced social motivation in the VPT group, there were no significant group differences in reported social functioning, as assessed by SRS-2. We found that in the VPT group higher FA values in segments of the left SLF I and right SLF II were associated with better social functioning. Surprisingly, the opposite was found for segments in the right IFO, where higher FA values were associated with worse reported social functioning. Since no significant correlations were found for the FT group, this relationship may be specific for VPT children. The current study overcomes methodological limitations of previous studies by more accurately segmenting white matter tracts using constrained spherical deconvolution based tractography, by applying complementary tractometry analysis approaches to estimate changes in FA more accurately, and by investigating the FA profile along the three components of the SLF.
... AFQ allows us to identify white matter pathways in children's native space and has been shown to reliably segment white matter pathways across a wide age-range of children. 30,31 Based on previous findings, we hypothesize that i) children with NF1 would have higher MD and lower FA across many major white matter pathways 16,27 and that ii) the magnitude of these differences would be affected by the age, such that MD/FA differences between children with NF1 and controls would be more pronounced in younger than older children. 24,26 2 Methods ...
Neurofibromatosis type 1 (NF1) is a common genetic condition in which 30-70% of children experience learning challenges including deficits in attention, executive function, and working memory. White matter pathways have been implicated in these cognitive functions; yet, they have not been well characterized in NF1. In this retrospective cohort study, we used diffusion MRI tractography to examine the microstructural properties of major white matter pathways in 20 children with NF1 aged 1 year to 18 years relative to 20 age- and sex-matched controls. An automated approach was used to identify and extract mean diffusivity (MD) and fractional anisotropy (FA) of eight cerebral white matter pathways bilaterally and the anterior and posterior part of the corpus callosum. Compared to controls, children with NF1 had significantly increased MD and significantly decreased FA in multiple white matter pathways including the anterior thalamic radiation, cingulate, uncinate fasciculus, inferior fronto-occipital fasciculus, arcuate fasciculus, and corticospinal tract. Differences in MD and FA remained significant after controlling for intracranial volume. In addition, MD and FA differences between children with NF1 and controls were greater at younger than older ages. These findings have implications for understanding the etiology of the neurocognitive deficits seen in many children with NF1.
... Furthermore, fractional anisotropy in the left superior longitudinal fasciculus 2 was positively associated with the comprehension of verbal instructions and spelling. In addition to our study, previous studies have also found correlations between fractional anisotropy in dorsal routes and language abilities in preterm children and adolescents [34][35][36][37]. In line with our findings, Mullen et al. [34] showed that phonological tasks were positively correlated with fractional anisotropy in the arcuate fasciculus, but bilaterally. ...
... Rights reserved. [35] demonstrated that reading skills were positively associated with fractional anisotropy in the arcuate fasciculus and in segments of anterior superior longitudinal fasciculus. In contrast, Bruckert et al. [11] found that fractional anisotropy in dorsal language pathways was related to reading outcomes in term but not preterm children. ...
Background
Prematurity and perinatal risk factors may influence white matter microstructure. In turn, these maturational changes may influence language development in this high-risk population of children.
Objective
To evaluate differences in the microstructure of association tracts between preterm and term children and between preterm children with appropriate growth and those with fetal growth restriction and to study whether the diffusion tensor metrics of these tracts correlate with language abilities in schoolchildren with no severe neurological impairment.
Materials and methods
This study prospectively followed 56 very preterm children (mean gestational age: 28.7 weeks) and 21 age- and gender-matched term children who underwent diffusion tensor imaging at a mean age of 9 years. We used automated probabilistic tractography and measured fractional anisotropy in seven bilateral association tracts known to belong to the white matter language network. Both groups participated in language assessment using five standardised tests at the same age.
Results
Preterm children had lower fractional anisotropy in the right superior longitudinal fasciculus 1 compared to term children (P < 0.05). Preterm children with fetal growth restriction had lower fractional anisotropy in the left inferior longitudinal fasciculus compared to preterm children with appropriate fetal growth (P < 0.05). Fractional anisotropy in three dorsal tracts and in two dorsal and one ventral tract had a positive correlation with language assessments among preterm children and preterm children with fetal growth restriction, respectively (P < 0.05).
Conclusion
There were some microstructural differences in language-related tracts between preterm and term children and between preterm children with appropriate and those with restricted fetal growth. Children with better language abilities had a higher fractional anisotropy in distinct white matter tracts.
... Children who are poor readers in the early primary grades rarely catch up with good readers ( Ozernov-Palchik et al., 2017 ). and ultimately experience lower academic and occupational attainment and reduced physical and mental health ( Arnold et al., 2005 ;Snowling et al., 2007 ). Understanding the neurobiology of individual differences in reading during childhood range of reading abilities because of potential variation in the neurobiology of reading in the two subgroups ( Bruckert et al., 2019 ;Dodson et al., 2018 ;Travis et al., 2016 ) A large body of literature has used diffusion MRI (dMRI) to investigate associations between individual differences in reading abilities in children and microstructural characteristics of white matter pathways in the brain ( Beaulieu et al., 2005 ;Meisler & Gabrieli, 2022 ;Vandermosten, Boets, Wouters, et al., 2012a ;Wandell & Yeatman, 2013 ). Many studies have found significant associations between reading and related abilities and fractional anisotropy (FA) in left hemisphere dorsal white matter pathways, specifically the arcuate fasciculus (Arc) and superior longitudinal fasciculus (SLF) ( Gullick & Booth, 2014 ;Myers et al., 2014 ;Saur et al., 2008 ;Y. ...
... However, negative associations between reading abilities and FA of the corpus callosum ( Dougherty et al., 2007 ;Odegard et al., 2009 ) have also been reported. Negative associations of reading and FA have also been found in the cerebellum ( Bruckert et al., 2020 ;Travis, Leitner, et al., 2015 ) and even in dorsal and ventral pathways in a modest sample of children (N = 19) across a wide age range (9-17 years) ( Travis et al., 2016 ). If we assume that rapid or efficient information transfer characterizes competent reading performance, then negative associations implicate properties other than myelin or axonal packing as the main drivers of the associations. ...
... Other possibilities might be increased axonal diameter or increased number of crossing fibers leading to increasing signal propagation. Variations, of course, might also be related to other differences across samples, such as socioeconomic status ( Ozernov-Palchik et al., 2019 ;Vanderauwera et al., 2019 ) or age and reading skill ( Travis et al., 2016 ). ...
Many diffusion magnetic resonance imaging (dMRI) studies document associations between reading skills and fractional anisotropy (FA) within brain white matter, suggesting that efficient transfer of information across the brain contributes to individual differences in reading. Use of complementary imaging methods can determine if these associations relate to myelin content of white matter tracts. Compared to children born at term (FT), children born preterm (PT) are at risk for reading deficits. We used two MRI methods to calculate associations of reading and white matter properties in FT and PT children. Participants (N=79: 36 FT and 43 PT) were administered the Gray's Oral Reading Test at age 8. We segmented three dorsal (left arcuate and bilateral superior longitudinal fasciculus) and four ventral (bilateral inferior longitudinal fasciculus and bilateral uncinate) tracts and quantified (1) FA from dMRI and (2) R1 from quantitative T1 relaxometry. We examined correlations between reading scores and these metrics along the trajectories of the tracts. Reading positively correlated with FA in segments of left arcuate and bilateral superior longitudinal fasciculi in FT children; no FA associations were found in PT children. Reading positively correlated with R1 in segments of the left superior longitudinal, right uncinate, and left inferior longitudinal fasciculi in PT children; no R1 associations were found in FT children. Birth group significantly moderated the associations of reading and white matter metrics. Myelin content of white matter may contribute to individual differences in PT but not FT children.
... Different 3D reconstruction tools can be used to assess the main direction of WM bundles in 3D. However, these tools, which are based on simple DTI considering a single fiber population per voxel, must be subject to caution due to the occurrence of false negatives (premature termination of a tract) or false positives (switch of another bundle crossing the same voxel) [40,41]. More complex tools can be used to deal with crossing fibers, but they require the acquisition of longer DTI sequences. ...
... Moreover, Li and al. gathered studies in a meta-analysis comparing PT versus term infants through different periods of life: term equivalent age, infancy, childhood, and adolescence [70]. The decreased FA of numerous WM fascicles persisted over every period of the timeline [40,[70][71][72]. One should bear in mind that FA values need to be interpreted according to the age of PT. ...
Preterm birth disrupts the in utero environment, preventing the brain from fully developing, thereby causing later cognitive and behavioral disorders. Such cerebral alteration occurs beneath an anatomical scale, and is therefore undetectable by conventional imagery. Prematurity impairs the microstructure and thus the histological process responsible for the maturation, including the myelination. Cerebral MRI diffusion tensor imaging sequences, based on water’s motion into the brain, allows a representation of this maturation process. Similarly, the brain’s connections become disorganized. The connectome gathers structural and anatomical white matter fibers, as well as functional networks referring to remote brain regions connected one over another. Structural and functional connectivity is illustrated by tractography and functional MRI, respectively. Their organizations consist of core nodes connected by edges. This basic distribution is already established in the fetal brain. It evolves greatly over time but is compromised by prematurity. Finally, cerebral plasticity is nurtured by a lifetime experience at microstructural and macrostructural scales. A preterm birth causes a negative and early disruption, though it can be partly mitigated by positive stimuli based on developmental neonatal care.
... Variations in the direction of association have been noted in other studies comparing term and preterm children. Travis et al. [52] found negative associations between tract FA and function in reading, in children born at term, and positive association between tract FA and function in reading in children born preterm. In the same sample of children we studied here, we found differences in degree [53] or directionality [52] of association between mean-tract FA and reading. ...
... Travis et al. [52] found negative associations between tract FA and function in reading, in children born at term, and positive association between tract FA and function in reading in children born preterm. In the same sample of children we studied here, we found differences in degree [53] or directionality [52] of association between mean-tract FA and reading. Thus, we interpret the statistical associations between FA of the ICP and internalizing behaviors to suggest that this tract is engaged in this domain, symptoms of internalizing behavioral problems. ...
Accumulating evidence suggests that the role of cerebellum includes regulation of behaviors; cerebellar impairment may lead to behavioral problems. Behavioral problems differ by sex: internalizing problems are more common in girls, externalizing problems in boys. Behavioral problems are also elevated in children born preterm (PT) compared to children born full term (FT). The current study examined internalizing and externalizing problems in 8-year-old children in relation to sex, birth-group, fractional anisotropy (FA) of the three cerebellar peduncles (superior, middle, and inferior), and interactions among these predictor variables. Participants (N = 78) were 44 boys (28 PT) and 34 girls (15 PT). We assessed behavioral problems via standardized parent reports and FA of the cerebellar peduncles using deterministic tractography. Internalizing problems were higher in children born PT compared to children born FT (p = .032); the interaction of sex and birth-group was significant (p = .044). When considering the contribution of the mean-tract FA of cerebellar peduncles to behavioral problems, there was a significant interaction of sex and mean-tract FA of the inferior cerebellar peduncle (ICP) with internalizing problems; the slope was negative in girls (p = .020) but not in boys. In boys, internalizing problems were only associated with mean-tract FA ICP in those born preterm (p = .010). We found no other significant associations contributing to internalizing or externalizing problems. Thus, we found sexual dimorphism and birth-group differences in the association of white matter metrics of the ICP and internalizing problems in school-aged children. The findings inform theories of the origins of internalizing behavioral problems in middle childhood and may suggest approaches to treatment at school age.
... Taken together, the ratio between the neurotransmitters' interchange and the role of CST in cortex maturation through the impacts of developing control of the cortex over the brainstem while the brainstem generates the synchronization within the ANS, suggests that an independent ontogenetic clock of self-regulation is seated in CST function and develops in a stepwise ontogenetic manner with direct and indirect effects on the emergence of executive functions later in childhood [112][113][114], and that this clock is sensitive to the balance between neurotransmitters and levels of synaptic storage during gestation and especially after early birth. ...
To date, there is no overarching proposition for the ontogenetic-neurobiological basis of self-regulation. This paper suggests that the balanced self-regulatory reaction of the fetus, newborn and infant is based on a complex mechanism starting from early brainstem development and continuing to progressive control of the cortex over the brainstem. It is suggested that this balance occurs through the synchronous reactivity between the sympathetic and parasympathetic systems, both which originate from the brainstem. The paper presents an evidence-based approach in which molecular excitation-inhibition balance, interchanges between excitatory and inhibitory roles of neurotransmitters as well as cardiovascular and white matter development across gestational ages, are shown to create sympathetic-parasympathetic synchrony, including the postnatal development of electroencephalogram waves and vagal tone. These occur in developmental milestones detectable in the same time windows (sensitive periods of development) within a convergent systematic progress. This ontogenetic stepwise process is termed “the self-regulation clock” and suggest that this clock is located in the largest connection between the brainstem and the cortex, the corticospinal tract. This novel evidence-based new theory paves the way towards more accurate hypotheses and complex studies of self-regulation and its biological basis, as well as pointing to time windows for interventions in preterm infants. The paper also describes the developing indirect signaling between the suprachiasmatic nucleus and the corticospinal tract. Finally, the paper proposes novel hypotheses for molecular, structural and functional investigation of the “clock” circuitry, including its associations with other biological clocks. This complex circuitry is suggested to be responsible for the developing self-regulatory functions and their neurobehavioral correlates.
... This finding highlights an important point: Association patterns between tractometry and cognitive measures may reveal differences that are invisible to tractometry alone. We see this in other domains as well, for example, differences in association patterns (without accompanying differences in tractometry) were found in comparisons between preterm and full term born children (Travis et al., 2016), high and low performing preschoolers (Qi et al., 2020), people with primary progressive aphasia and controls (Janssen et al., 2020). ...
Introduction
Individuals with persistent developmental stuttering display deficits in aligning motor actions to external cues (i.e., sensorimotor synchronization). Diffusion imaging studies point to stuttering-associated differences in dorsal, not ventral, white matter pathways, and in the cerebellar peduncles. Here, we studied microstructural white matter differences between adults who stutter (AWS) and fluent speakers using two complementary approaches to: (a) assess previously reported group differences in white matter diffusivity, and (b) evaluate the relationship between white matter diffusivity and sensorimotor synchronization in each group.
Methods
Participants completed a sensorimotor synchronization task and a diffusion MRI scan. We identified the cerebellar peduncles and major dorsal- and ventral-stream language pathways in each individual and assessed correlations between sensorimotor synchronization and diffusion measures along the tracts.
Results
The results demonstrated group differences in dorsal, not ventral, language tracts, in alignment with prior reports. Specifically, AWS had significantly lower fractional anisotropy (FA) in the left arcuate fasciculus, and significantly higher mean diffusivity (MD) in the bilateral frontal aslant tract compared to fluent speakers, while no significant group difference was detected in the inferior fronto-occipital fasciculus. We also found significant group differences in both FA and MD of the left middle cerebellar peduncle. Comparing patterns of association with sensorimotor synchronization revealed a novel double dissociation: MD within the left inferior cerebellar peduncle was significantly correlated with mean asynchrony in AWS but not in fluent speakers, while FA within the left arcuate fasciculus was significantly correlated with mean asynchrony in fluent speakers, but not in AWS.
Conclusions
Our results support the view that stuttering involves altered connectivity in dorsal tracts and that AWS may rely more heavily on cerebellar tracts to process timing information. Evaluating microstructural associations with sensitive behavioral measures provides a powerful tool for discovering additional functional differences in the underlying connectivity in AWS.
