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Showing papers on "Inferior longitudinal fasciculus published in 2020"


Journal ArticleDOI
TL;DR: Shape analysis was used to derive length, area, volume, and shape metrics from diffusion MRI tractography and utilized them to study the morphology of human association pathways to show that the overall layout of the association pathways does not variate a lot across subjects, as shown by low between-subject variation.

65 citations


Journal ArticleDOI
TL;DR: Findings suggest that PNSE is associated with altered development of specific frontolimbic pathways in preterm neonates as early as term-equivalent age.

55 citations


Journal ArticleDOI
TL;DR: This study aimed to investigate the mechanism and effective indicators to predict WMH‐related cognitive impairment and to determine the most common neuroimaging manifestation of cerebral small vessel disease.
Abstract: Aims White matter hyperintensity (WMH) is the most common neuroimaging manifestation of cerebral small vessel disease and is related to cognitive dysfunction or dementia. This study aimed to investigate the mechanism and effective indicators to predict WMH-related cognitive impairment. Methods We recruited 22 healthy controls (HC), 25 cases of WMH with normal cognition (WMH-NC), and 23 cases of WMH with mild cognitive impairment (WMH-MCI). All individuals underwent diffusion tensor imaging (DTI) and a standardized neuropsychological assessment. Automated Fiber Quantification was used to extract altered DTI metrics between groups, and partial correlation was performed to assess the associations between WM integrity and cognitive performance. Furthermore, machine learning analyses were performed to determine underlying imaging markers of WMH-related cognitive impairment. Results Our study found that mean diffusivity (MD) values of several fiber bundles including the bilateral anterior thalamic radiation (ATR), the left inferior fronto-occipital fasciculus (IFOF), the right inferior longitudinal fasciculus (ILF), and the right superior longitudinal fasciculus (SLF) were negatively correlated with memory function, while that of the anterior component of the right IFOF and the posterior and intermediate component of the right ILF showed significant negative correlation with MMSE and episodic memory, respectively. Furthermore, machine learning analyses showed that the accuracy of recognizing WMH-MCI patients from the WMH populations was up to 80.5% and the intermediate and posterior components of the right ILF and the anterior component of the right IFOF contribute the most. Conclusions Changes in the properties of DTI may be the potential mechanism of WMH-related MCI, especially the right IFOF and the right ILF, which may become imaging markers for predicting WMH-related cognitive dysfunction.

50 citations


Journal ArticleDOI
TL;DR: This study highlights the principal white-matter pathways of the ITG and demonstrates key underlying connections through DSI-based fibre tracking and presents a summary of the relevant clinical anatomy for this region of the cerebrum as part of a larger effort to understand it in its entirety.

48 citations


Journal ArticleDOI
TL;DR: It is suggested that an increased expression of psychopathology is closely linked to lower rates of myelin maturation in selective brain tracts over time, and impaired myelin growth in limbic association fibres may serve as a neural marker for emerging mental illness during the course of adolescence and early adulthood.
Abstract: Adolescence is a time period associated with marked brain maturation that coincides with an enhanced risk for onset of psychiatric disorder. White matter tract myelination, a process that continues to unfold throughout adolescence, is reported to be abnormal in several psychiatric disorders. Here, we ask whether psychiatric vulnerability is linked to aberrant developmental myelination trajectories. We assessed a marker of myelin maturation, using magnetisation transfer (MT) imaging, in 10 major white matter tracts. We then investigated its relationship to the expression of a general psychopathology "p-factor" in a longitudinal analysis of 293 healthy participants between the ages of 14 and 24. We observed significant longitudinal MT increase across the full age spectrum in anterior thalamic radiation, hippocampal cingulum, dorsal cingulum and superior longitudinal fasciculus. MT increase in the inferior fronto-occipital fasciculus, inferior longitudinal fasciculus and uncinate fasciculus was pronounced in younger participants but levelled off during the transition into young adulthood. Crucially, longitudinal MT increase in dorsal cingulum and uncinate fasciculus decelerated as a function of mean p-factor scores over the study period. This suggests that an increased expression of psychopathology is closely linked to lower rates of myelin maturation in selective brain tracts over time. Impaired myelin growth in limbic association fibres may serve as a neural marker for emerging mental illness during the course of adolescence and early adulthood.

41 citations


Posted ContentDOI
20 Apr 2020-bioRxiv
TL;DR: Shape analysis was used to derive length, area, volume, and shape metrics from diffusion MRI tractography and utilized them to study the morphology of human association pathways to show that the overall layout of the association pathways does not variate a lot across subjects, as shown by low between-subject variation.
Abstract: Shape analysis has been widely used in digital image processing and computer vision, but they have not been utilized to compare the structural characteristics of the human association pathways. Here we used shape analysis to derive length, area, volume, and shape metrics from diffusion MRI tractography and utilized them to study the human association pathways. An augmented fiber tracking combined with automatic segmentation was used to improve reproducibility in tractography. The reliability analysis showed that shape descriptors achieved moderate to good test-retest reliability. Further analysis on association pathways showed left dominance in the arcuate fasciculus, cingulum, uncinate fasciculus, frontal aslant tract, and right dominance in the inferior fronto-occipital fasciculus and inferior longitudinal fasciculus. The superior longitudinal fasciculus has a mixed lateralization profile with different metrics showing either left or right dominance. The analysis of between-subject variations shows that the overall layout of the association pathways does not variate a lot across subjects, as shown by low between-subject variation in length, span, diameter, and radius. In contrast, the area of the pathway innervation region has a considerable between-subject variation. A follow-up analysis is warranted to thoroughly investigate the nature of population variations and their structure-function correlation.

37 citations


Journal ArticleDOI
TL;DR: The white matter structural network model provided superior prediction of impairment and contributed the most to the network model in left and right temporal lobe epilepsy patients with systemic language impairment.

30 citations


Journal ArticleDOI
TL;DR: Findings suggest that childhood maltreatment is associated with widespread WM microstructural abnormalities particularly evident in the fornix, corpus callosum and optic radiations, where the neural pathways linking fronto-limbic and occipital visual cortices presumably involved in conveying and processing the (aversive) experience may be compromised in this population.

30 citations


Journal ArticleDOI
TL;DR: A crucial role of VOF is suggested in integrating visual information to link the broad visual cortex as well as in connecting the dual visual stream.
Abstract: The vertical occipital fasciculus (VOF) is an association fiber tract coursing vertically at the posterolateral corner of the brain. It is re-evaluated as a major fiber tract to link the dorsal and ventral visual stream. Although previous tractography studies showed the VOF’s cortical projections fall in the dorsal and ventral visual areas, the post-mortem dissection study for the validation remains limited. First, to validate the previous tractography data, we here performed the white matter dissection in post-mortem brains and demonstrated the VOF’s fiber bundles coursing between the V3A/B areas and the posterior fusiform gyrus. Secondly, we analyzed the VOF’s structural connectivity with diffusion tractography to link vision-associated cortical areas of the HCP MMP1.0 atlas, an updated map of the human cerebral cortex. Based on the criteria the VOF courses laterally to the inferior longitudinal fasciculus (ILF) and craniocaudally at the posterolateral corner of the brain, we reconstructed the VOF’s fiber tracts and found the widespread projections to the visual cortex. These findings could suggest a crucial role of VOF in integrating visual information to link the broad visual cortex as well as in connecting the dual visual stream.

28 citations


Journal ArticleDOI
TL;DR: The complex functional processes attributed to the lateral occipital lobe, including object recognition, facial recognition, and motion perception are likely related to the subcortical white matter tracts described within this study.
Abstract: White matter tracts link different regions of the brain, and the known functions of those interconnected regions may offer clues about the roles that white matter tracts play in information relay. The authors of this report discuss the structure and function of the lateral occipital lobe and how the lateral occipital lobe communicates with other regions via white matter tracts. The authors used generalized q-sampling imaging and cadaveric brain dissections to uncover the subcortical white matter connections of the lateral occipital lobe. The authors created GQI of ten healthy controls and dissected ten cadaveric brains. The middle longitudinal fasciculus, vertical occipital fasciculus, inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, optic radiations, and a diverse array of U-shaped fibers connect the lateral occipital lobe to itself, parts of the temporal, parietal, and medial occipital cortices. The complex functional processes attributed to the lateral occipital lobe, including object recognition, facial recognition, and motion perception are likely related to the subcortical white matter tracts described within this study. There was good concordance between the white matter tracts generated using GQI and the white matter tracts that were found after dissection of the cadaveric brains. This article presents the anatomic connections of the lateral occipital lobe and discusses the associated functions.

26 citations


Journal ArticleDOI
TL;DR: Microstructural alterations of the limbic and cortico-cortical tracts could be potential biomarkers for early diagnosis in preclinical disease phase.
Abstract: Object: Alzheimer's disease is a progressive, irreversible neurodegenerative disorder associated with brain alterations. Diffusion tensor imaging (DTI) has contributed to identify degeneration in white matter cortical microstructural that can be considered an early and specific biomarker for Alzheimer's disease. This review aimed to provide a summary of DTI studies on white matter damage in Alzheimer's disease.Methods: On PubMed, Web of Science and Scopus databases, we reviewed the studies that used DTI for assessing fractional anisotropy in neurofiber tracts involved in Alzheimer's Disease progression: fornix, the cingulum, uncinate fasciculus, superior and inferior longitudinal fasciculus and corpus callosum. We included nine studies that met search criteria.Results: The results showed decreased fractional anisotropy value in mild cognitive impairment (MCI) patients. White matter diffusivity changes were associated with the progression of Alzheimer's disease.Conclusion: Microstructural alterations of the limbic and cortico-cortical tracts could be potential biomarkers for early diagnosis in preclinical disease phase.

Journal ArticleDOI
01 Mar 2020-Cortex
TL;DR: The functional relevance of the fornix for human spatial learning in a virtual reality environment is demonstrated, and the importance of a distributed neuroanatomical network, underpinned by key white matter pathways, such as thefornix, in complex spatial behaviour is highlighted.

Journal ArticleDOI
TL;DR: Direct evidence for the importance of the integrity of the ventral language stream, in particular the left IFOF, in semantic processing deficits in SSD is found.

Journal ArticleDOI
TL;DR: Novel insights are provided into the putative role of WM tract abnormalities in the pathogenesis of PD-P by demonstrating significant alterations in several WM tracts.
Abstract: Objective The objective of the current study was to compare the microstructural integrity of the white matter (WM) tracts in patients having Parkinson disease (PD) with and without psychosis (PD-P and PD-NP) through diffusion tensor imaging (DTI). Methods This cross-sectional study involved 48 PD-NP and 42 PD-P who were matched for age, sex, and education. Tract-based spatial statistics (TBSS) was used to compare several DTI metrics from the diffusion-weighted MRIs obtained through a 3-Tesla scanner. A set of neuropsychological tests was used for the cognitive evaluation of all patients. Results The severity and stage of PD were not statistically different between the groups. The PD-P group performed poorly in all the neuropsychological domains compared with the PD-NP group. TBSS analysis revealed widespread patterns of abnormality in the fractional anisotropy (FA) in the PD-P group, which also correlated with some of the cognitive scores. These tracts include inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, right parieto-occipital WM, body of the corpus callosum, and corticospinal tract. Conclusion This study provides novel insights into the putative role of WM tract abnormalities in the pathogenesis of PD-P by demonstrating significant alterations in several WM tracts. Additional longitudinal studies are warranted to confirm the findings of our research.

Journal ArticleDOI
TL;DR: Naming recovery in subacute aphasia is associated with change in the integrity of the right ILF, and changes in FA values and change in BNT score were investigated.
Abstract: Background. Despite progress made in understanding functional reorganization patterns underlying recovery in subacute aphasia, the relation between recovery and changes in white matter structure remains unclear. Objective. To investigate changes in dorsal and ventral language white matter tract integrity in relation to naming recovery in subacute poststroke aphasia. Methods. Ten participants with aphasia after left-hemisphere stroke underwent language testing and diffusion tensor imaging twice within 3 months post onset, with a 1-month interval between sessions. Deterministic tractography was used to bilaterally reconstruct the superior longitudinal fasciculus (SLF), inferior fronto-occipital fasciculus (IFOF), inferior longitudinal fasciculus (ILF), middle longitudinal fasciculus (MdLF), and uncinate fasciculus (UF). Per tract, the mean fractional anisotropy (FA) was extracted as a measure of microstructural integrity. Naming accuracy was assessed with the Boston Naming Test (BNT). Correlational analyses were performed to investigate the relationship between changes in FA values and change in BNT score. Results. A strong positive correlation was found between FA change in the right ILF within the ventral stream and change on the BNT (r = 0.91, P < .001). An increase in FA in the right ILF was associated with considerable improvement of naming accuracy (range BNT change score: 12-14), a reduction with limited improvement or slight deterioration. No significant correlations were found between change in naming accuracy and FA change in any of the other right or left ventral and dorsal language tracts. Conclusions. Naming recovery in subacute aphasia is associated with change in the integrity of the right ILF.

Journal ArticleDOI
TL;DR: The findings suggest that autistic males have an altered trajectory of white matter maturation relative to controls, and future longitudinal analyses are required to further characterize the extent and time course of these differences.
Abstract: Autism spectrum condition (ASC) is accompanied by developmental differences in brain anatomy and connectivity. White matter differences in ASC have been widely studied with diffusion imaging but results are heterogeneous and vary across the age range of study participants and varying methodological approaches. To characterize the neurodevelopmental trajectory of white matter maturation, it is necessary to examine a broad age range of individuals on the autism spectrum and typically developing controls, and investigate age × group interactions. Here, we employed a spatially unbiased tract-based spatial statistics (TBSS) approach to examine age-related differences in white matter connectivity in a sample of 41 individuals with ASC, and 41 matched controls between 7–17 years of age. We found significant age-related differences between the ASC and control group in widespread brain regions. This included age-related differences in the uncinate fasciculus, corticospinal tract, inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, anterior thalamic radiation, superior longitudinal fasciculus and forceps major. Measures of fractional anisotropy (FA) were significantly positively associated with age in both groups. However, this relationship was significantly stronger in the ASC group relative to controls. Measures of radial diffusivity (RD) were significantly negatively associated with age in both groups, but this relationship was significantly stronger in the ASC group relative to controls. The generalisability of our findings is limited by the restriction of the sample to right-handed males with an IQ > 70. Furthermore, a longitudinal design would be required to fully investigate maturational processes across this age group. Taken together, our findings suggest that autistic males have an altered trajectory of white matter maturation relative to controls. Future longitudinal analyses are required to further characterize the extent and time course of these differences.

Journal ArticleDOI
TL;DR: Primary brain tumor patients experience language fluency and naming function may be explained by microstructural injury to left-sided perisylvian white matter, representing potential dose-avoidance targets for language preservation.
Abstract: Purpose Our purpose was to investigate the association between imaging biomarkers of radiation-induced white matter (WM) injury within perisylvian regions and longitudinal language decline in patients with brain tumors. Methods and Materials Patients with primary brain tumors (n = 44) on a prospective trial underwent brain magnetic resonance imaging, diffusion-weighted imaging, and language assessments of naming (Boston Naming Test [BNT]) and fluency (Delis–Kaplan Executive Function System Category Fluency [DKEFS-CF]) at baseline and 3, 6, and 12 months after fractionated radiation therapy (RT). Reliable change indices of language function (0-6 months), accounting for practice effects (RCI-PE), evaluated decline. Bilateral perisylvian WM regions (superficial WM subadjacent to Broca’s area and the superior temporal gyrus [STG], inferior longitudinal fasciculus [ILF], inferior fronto-occipital fasciculus [IFOF], and arcuate fasciculus) were autosegmented. We quantified volume and diffusion measures of WM microstructure: fractional anisotropy (FA; lower values indicate disruption) and mean diffusivity (MD; higher values indicate injury). Linear mixed-effects models assessed mean dose as predictor of imaging biomarker change and imaging biomarkers as longitudinal predictors of language scores. Results DKEFS-CF scores declined at 6 months post-RT (RCI-PE, -0.483; P = .01), whereas BNT scores improved (RCI-PE, 0.262; P = .04). Higher mean dose to left and right regions was predictive of decreased volume (left-STG, P = .02; right-ILF and IFOF, P = .03), decreased FA (left-WM tracts, all P Conclusions Patients with primary brain tumors experience language fluency decline post-RT. Poorer fluency and naming function may be explained by microstructural injury to left-sided perisylvian WM, representing potential dose-avoidance targets for language preservation.

Journal ArticleDOI
TL;DR: Left UF and IFO may be the key brain regions affecting arithmetic function, while bilateral IFO has an effect on intelligence in patients with Moyamoya disease and controls.
Abstract: Ischemic Moyamoya disease is one of the important causes of stroke, which leads to severe impairment in cognitive functions. This cognitive impairment occurs prior to stroke. However, the cognitive functions that are impaired and the mechanisms of these impairments have not been determined. We analyzed 12 patients with Moyamoya disease and 12 controls. All participants underwent cognitive tests and magnetic resonance imaging (MRI) scans. The diffusion tensor imaging (DTI) data was processed using Tract-Based Spatial Statistics (TBSS). Significantly different white matter areas were correlated with different cognitive functions. There were significant differences in intelligence and subtraction between the patients and controls (p < 0.05). The parameters of DTI such as fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) have different changes in anterior thalamic radiation, inferior fronto-occipital fasciculus (IFO), superior longitudinal fasciculus (SLF), uncinate fasciculus (UF), inferior longitudinal fasciculus, forceps minor, and other regions between the two groups. Left UF and IFO may be the key brain regions affecting arithmetic function, while bilateral IFO has an effect on intelligence. RD and AD may be better indicators for early prediction of chronic white matter damage than FA, while MD tends to have a comprehensive indirect change. There is cognitive impairment in ischemic MMD, which is closely related to white matter impairment. Clinical Trial Registration, Unique identifier: ChiCTR1900023610 . Registered 4 June 2019 – Prospective study registered.

Journal ArticleDOI
TL;DR: This study used voxel-based lesion-symptom mapping to examine the cortical and white matter regions associated with language production impairments in a sample of 63 preoperative tumour patients, and concludes that the study of tumours offers evidence that complements that available from other populations.

Journal ArticleDOI
TL;DR: It is found that FW was associated with baseline memory and executive function beyond that of hippocampal volume and other comorbidities and should be included in theoretical models of aging, cerebrovascular disease, and Alzheimer's disease.

Journal ArticleDOI
TL;DR: A systematic review of the literature with a focus on anatomo-functional correlations obtained from direct electrostimulation during awake tumor surgery, and conducted between diffusion tensor imaging metrics and behavioral semantic performance in healthy and aphasic individuals suggested that the left inferior fronto-occipital fasciculus contributes to the essential connectivity that allows semantic processing.

Journal ArticleDOI
TL;DR: The results delineate the neural correlates of white-matter microstructure to behavioral language and cognitive performance in white- Matter tracts related to language and Cognitive abilities at the tract level along with development.
Abstract: Extensive improvements in executive functions and language abilities are accompanied by changes in functional connections within the brain and in gray and white matter during the first few years of life. Diffusion tensor imaging provides a unique look into pediatric brain anatomy and critical information regarding white-matter development. The aims of the current study were to investigate the variability in diffusion indices in language and cognitive white-matter tracts, hemispheric lateralization, and how diffusion measures are related to age, language and cognitive abilities from early toddler age to early childhood. Diffusion tensor imaging data were acquired from seventy-four 17–107 month-old typically developing children (mean = 69 months; females = 39). Effects of hemisphere and age on diffusion properties (mean diffusivity, radial diffusivity, axial diffusivity and fractional anisotropy) were measured at 100 points along the length of white-matter tracts related to expressive language and cognitive abilities, including the cingulum bundle, superior longitudinal fasciculus, inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, arcuate fasciculus and corpus callosum (forceps major and forceps minor). Diffusion properties exhibited variability along the length of the tracts, with hemispheric effect and age differences in specific segments of the tracts. Significant positive correlation was found between fractional anisotropy and expressive language and cognitive abilities. Our results provide a detailed examination of the effect of age and hemisphere on diffusion properties. Furthermore, the results delineate the neural correlates of white-matter microstructure to behavioral language and cognitive performance in white-matter tracts related to language and cognitive abilities at the tract level along with development.

Journal ArticleDOI
TL;DR: The findings indicate that a large-scale emotional brain network is affected in BPD with alterations in MD and FA of WM prefrontal-limbic pathways of the heteromodal association cortex involved in emotion processing and emotion regulation.

Journal ArticleDOI
TL;DR: Women with BED show WM alterations in AD in fronto-limbic and parietal pathways that are important in decision-making processes, as BMI was a covariate in the analyses.
Abstract: Objective Research on potential brain circuit abnormalities in binge eating disorder (BED) is limited. Here, we assess white matter (WM) microstructure in obese women with BED. Method Diffusion tensor imaging data were acquired, and tract-based spatial statistics used to examine WM in women with BED who were obese (n = 17) compared to normal-weight (NWC) (n = 17) and to women who were obese (OBC) (n = 13). Body mass index (BMI) was a covariate in the analyses. Results The BED group (vs. NWC) had greater axial diffusion (AD) in the forceps minor, anterior thalamic radiation, superior and inferior longitudinal fasciculus, that is, in pathways connecting fronto-limbic regions. Microstructures differences in AD between the BED and OBC groups were seen in fronto-limbic pathways extending to temporoparietal pathways. The BED (vs. OBC) group had greater fractional anisotropy in the forceps minor and greater AD in the superior longitudinal fasciculus, cingulate gyrus, and corpus callosum, consistent with fronto-tempoparietal pathways. Conclusion Women with BED show WM alterations in AD in fronto-limbic and parietal pathways that are important in decision-making processes. As BMI was a covariate in the analyses, alterations in BED may be part of the pathology, but whether they are a cause or effect of illness is unclear.

Posted ContentDOI
12 Jun 2020-bioRxiv
TL;DR: This study finds reliable evidence supporting the existence of direct white matter connections between individually and functionally defined hMT+/V5 and hPT and proposes to name the middle (or motion) occipito-temporal track (MOTT).
Abstract: In humans, the occipital middle-temporal region (hMT+/V5) specializes in the processing of visual motion, while the Planum Temporale (hPT) specializes in auditory motion processing. It has been hypothesized that these regions might communicate directly to achieve fast and optimal exchange of multisensory motion information. In this study, we investigated for the first time in humans the existence of direct white matter connections between visual and auditory motion-selective regions using a combined functional- and diffusion-MRI approach. We found reliable evidence supporting the existence of direct white matter connections between individually and functionally defined hMT+/V5 and hPT. We show that projections between hMT+/V5 and hPT do not overlap with large white matter bundles such as the Inferior Longitudinal Fasciculus (ILF) nor the Inferior Frontal Occipital Fasciculus (IFOF). Moreover, we did not find evidence for the existence of reciprocal projections between the face fusiform area and hPT, supporting the functional specificity of hMT+/V5 - hPT connections. Finally, evidence supporting the existence of hMT+/V5 - hPT connections was corroborated in a large sample of participants (n=114) from the human connectome project. Altogether, this study provides first evidence supporting the existence of direct occipito-temporal projections between hMT+/V5 and hPT which may support the exchange of motion information between functionally specialized auditory and visual regions and that we propose to name the middle (or motion) occipito-temporal track (MOTT).

Posted ContentDOI
07 Jan 2020-bioRxiv
TL;DR: It is suggested that white matter has a unique role in cognitive decline and, therefore, could be used to provide better disease staging, allowing for more precise disease monitoring in AD.
Abstract: Objective: Hippocampal volume is a sensitive marker of neurodegeneration and a well-established predictor of age-related cognitive impairment. Recently, free-water (FW) magnetic resonance imaging (MRI) has shown associations with pathology in Alzheimer9s disease (AD), but it is still unclear whether these metrics are associated with measures of cognitive impairment. Here, we investigate whether FW and FW-corrected fractional anisotropy (FAT) within medial temporal lobe white matter tracts (cingulum, fornix, uncinate fasciculus, inferior longitudinal fasciculus, and tapetum) provides meaningful contribution to cognition and cognitive decline beyond hippocampal volume. Participants and Methods: Vanderbilt Memory & Aging Project participants (n=319, 73±7 years, 59% male) with normal cognition and mild cognitive impairment (40% of cohort) underwent baseline brain MRI, including structural MRI to quantify hippocampal volume, diffusion MRI to quantify medial temporal lobe white matter tract FW and FAT, and longitudinal neuropsychological assessment with a mean follow-up of 3.5 years. Linear regressions were conducted to determine how hippocampal volume and white matter tract FW and FAT interact with baseline memory and executive function performances. Competitive model analyses determined the unique variance provided by white matter tract FW and FAT beyond that of hippocampal volume and other comorbidities. Linear mixed-effects models were conducted to determine how baseline hippocampal volume and white matter tract FW and FAT interact to explain longitudinal change in memory and executive function performances. Results: FW in the inferior longitudinal fasciculus, tapetum, uncinate fasciculus, and cingulum were robustly associated with baseline memory and executive function. Further, competitive model analysis showed that tract FW contributed unique variance beyond other comorbidities and hippocampal volume for memory (ΔRadj2 range: 0.82-2.00%) and executive function (ΔRadj2 range: 0.88-1.87%). Longitudinal analyses demonstrated significant interactions of hippocampal volume and FAT in the inferior longitudinal fasciculus (p=0.02), tapetum (p=0.02), uncinate fasciculus (p=0.02), and cingulum (p=0.002) with decline in memory. For decline in executive function, we found significant interactions of hippocampal volume and FAT in inferior longitudinal fasciculus (p=0.03), tapetum (p=0.02), uncinate fasciculus (p=0.02), and fornix (p=0.02), as well as cingulum (p=0.02) and fornix (p=0.02) FW. Conclusions: Our results highlight novel associations between FW and FAT measures of medial temporal lobe tract microstructure and cognitive performance such that individuals with smaller hippocampal volumes and lower tract microstructure experience greater cognitive decline. These results suggest that white matter has a unique role in cognitive decline and, therefore, could be used to provide better disease staging, allowing for more precise disease monitoring in AD.

Journal ArticleDOI
TL;DR: In this paper, the effects of white matter connectivity on social-emotional perception in schizophrenia and its impact on patients' clinical symptoms and long-term outcomes were examined and the results suggest that the uncinate fasciculus could affect the pathophysiology of schizophrenia.

Journal ArticleDOI
TL;DR: Diminished white matter density in pathways connecting limbic and cortical regions is associated with childhood aggression and abnormal interhemispheric connectivity via corpus callosum may also reflect a potential neural mechanism involved in aggression.

Journal ArticleDOI
TL;DR: A double disconnection mechanism in Pr MS affecting communication both inside the ToM network and between the Tom network and cognitive execution areas is highlighted, likely explaining the deficit in cognitive ToM.
Abstract: The relationship between cognitive and affective theory of mind (ToM), clinical variables, and brain tissue injury is still a subject of debate in multiple sclerosis (MS). By adopting a ToM Networks model, we investigated ToM performance, and brain imaging correlates in relapsing-remitting (RR) and progressive (Pr) MS. 16RR, 19Pr, and 21 healthy controls were assessed with both cognitive (CToM) and affective ToM (AToM) tests and neuropsychological tools and were evaluated with MRI. Cortical thickness, sub-cortical volumetry, and tract-based-spatial-statistics were analyzed. Our results reported a CToM deficit in Pr, correlated with attention. While no relation between gray matter and CToM was observed, a widespread correlation between CToM and normal-appearing white matter was found. In particular, we registered a significant positive correlation between CToM and fractional anisotropy in Superior and Inferior Longitudinal Fasciculus and right thalamic radiation tracts. Moreover, an inverse correlation between CToM and mean diffusivity of the right fronto-occipital fasciculus, bilateral superior longitudinal fasciculus, cortico-spinal, left uncinate, corpus callosum, and forceps minor tracts was also observed. This work highlighted a double disconnection mechanism in Pr MS affecting communication both (1) inside the ToM network and (2) between the ToM network and cognitive execution areas, likely explaining the deficit in cognitive ToM.

Journal ArticleDOI
TL;DR: This research demonstrates language lateralization differences between patient groups with lTLE and rTLE, and corresponding differences in the connectivity strength of the ILF, IFOF, and UF.