Articles de revues : « Uncinate fasciculu »

1

Peltier, Johann, Sébastien Verclytte, Christine Delmaire, Jean-Pierre Pruvo, Olivier Godefroy et Daniel Le Gars. « Microsurgical anatomy of the temporal stem : clinical relevance and correlations with diffusion tensor imaging fiber tracking ». Journal of Neurosurgery 112, n^o 5 (mai 2010) : 1033–38. http://dx.doi.org/10.3171/2009.6.jns08132.

Texte intégral

Résumé :

Object The authors used a fiber dissection technique to describe the temporal stem and explain the tendency of malignant tumors to spread within both the frontal and temporal lobes. The authors focused on the morphological characteristics and course of various fasciculi of the temporal stem, including the uncinate fascicle, occipitofrontal fascicle, anterior commissure, loop of the optic radiations (Meyer loop), and the ansa peduncularis. Methods Eight previously frozen, formalin-fixed human brains were dissected under an operating microscope using the fiber dissection technique described by Klingler. Lateral, inferior, and medial approaches were made. Cross-sectional 3D MR images obtained in 10 patients without brain lesions demonstrated that fibers of the temporal stem, which were intermingled together in various ways, curved laterally within the basal forebrain. Various pathological entities affecting the temporal stem are described and discussed. Results The uncinate fascicle has 3 portions: a ventral extension, an intermediary segment called the isthmus, and a dorsal segment. The inferior occipitofrontal fasciculus is a layer of more superficial white matter that appeared to be superior to the uncinate fasciculus. A short ventral portion of the radiations of the corpus callosum was sometimes noted to run ventrally to enter the temporal stem and to reach both temporal lobes. Conclusions To the authors' knowledge, a detailed anatomy of the temporal stem has not been previously described in the literature. The unique anatomy of the temporal stem provides a route for tumor spread between the frontal and temporal lobes.

Styles APA, Harvard, Vancouver, ISO, etc.

2

David, Szabolcs, Lieke Heesink, Elbert Geuze, Thomas Gladwin, Jack van Honk, Rolf Kleber et Alexander Leemans. « Regions of white matter abnormalities in the arcuate fasciculus in veterans with anger and aggression problems ». Brain Structure and Function 225, n^o 4 (27 décembre 2019) : 1401–11. http://dx.doi.org/10.1007/s00429-019-02016-2.

Texte intégral

Résumé :

AbstractAggression after military deployment is a common occurrence in veterans. Neurobiological research has shown that aggression is associated with a dysfunction in a network connecting brain regions implicated in threat processing and emotion regulation. However, aggression may also be related to deficits in networks underlying communication and social cognition. The uncinate and arcuate fasciculi are integral to these networks, thus studying potential abnormalities in these white matter connections can further our understanding of anger and aggression problems in military veterans. Here, we use diffusion tensor imaging tractography to investigate white matter microstructural properties of the uncinate fasciculus and the arcuate fasciculus in veterans with and without anger and aggression problems. A control tract, the parahippocampal cingulum was also included in the analyses. More specifically, fractional anisotropy (FA) estimates are derived along the trajectory from all fiber pathways and compared between both groups. No between-group FA differences are observed for the uncinate fasciculus and the cingulum, however parts of the arcuate fasciculus show a significantly lower FA in the group of veterans with aggression and anger problems. Our data suggest that abnormalities in arcuate fasciculus white matter connectivity that are related to self-regulation may play an important role in the etiology of anger and aggression in military veterans.

Styles APA, Harvard, Vancouver, ISO, etc.

3

Ribbeck Lourdes, Simbrón, Sandoval Paredes Josefina, Amador Sánchez Karen et Taboada Barajas Jesús. « Uncinate Fasciculus in Temporal Lobe Epilepsy ». Brain and Neurological Disorders 2, n^o 2 (7 octobre 2019) : 01–04. http://dx.doi.org/10.31579/2642-973x/010.

Texte intégral

Résumé :

Background and purpose: Temporal lobe epilepsy is the most common focal intractable epilepsy. Uncinate fasciculus is a white fiber bundle that connects the orbitofrontal cortex with the anterior temporal lobe, and is implicated in most of the superior mental functions. There is evidence of uncinate fasciculus as a propagation pathway of seizures from temporal lobe. The aim of the study is to determine uncinate fasciculus alterations in patients with temporal lobe epilepsy, through fractional anisotropy. Methods: Thirty-three patients with temporal lobe epilepsy (10 right and 23 left) were studied. All of them were right-handed and had left hemisphere dominance for language. A 1.5 T MR imaging scanner was used to obtain diffusion tensor imaging (DTI). Fractional anisotropy of uncinate fasciculus was calculated through TBSS (Tract Based Spatial Statistics). Statistical analysis was done using IBM SPSS (v. 25). Results: Fractional anisotropy was higher in right uncinate fasciculus, regardless of epilepsy side. Right uncinate fasciculus, at the insula level, showed lower fractional anisotropy in patients with right temporal lobe epilepsy. Conclusions: Results support the evidence of uncinate fasciculus as a pathway of propagation in temporal lobe epilepsy, specially at insular level.

Styles APA, Harvard, Vancouver, ISO, etc.

4

Foley, Sonya F., Matthew Bracher-Smith, Katherine E. Tansey, Judith R. Harrison, Greg D. Parker et Xavier Caseras. « Fractional anisotropy of the uncinate fasciculus and cingulum in bipolar disorder type I, type II, unaffected siblings and healthy controls ». British Journal of Psychiatry 213, n^o 3 (21 juin 2018) : 548–54. http://dx.doi.org/10.1192/bjp.2018.101.

Texte intégral

Résumé :

BackgroundFractional anisotropy in the uncinate fasciculus and the cingulum may be biomarkers for bipolar disorder and may even be distinctly affected in different subtypes of bipolar disorder, an area in need of further research.AimsThis study aims to establish if fractional anisotropy in the uncinate fasciculus and cingulum shows differences between healthy controls, patients with bipolar disorder type I (BD-I) and type II (BD-II), and their unaffected siblings.MethodFractional anisotropy measures from the uncinate fasciculus, cingulum body and parahippocampal cingulum were compared with tractography methods in 40 healthy controls, 32 patients with BD-I, 34 patients with BD-II, 17 siblings of patients with BD-I and 14 siblings of patients with BD-II.ResultsThe main effects were found in both the right and left uncinate fasciculus, with patients with BD-I showing significantly lower fractional anisotropy than both patients with BD-II and healthy controls. Participants with BD-II did not differ from healthy controls. Siblings showed similar effects in the left uncinate fasciculus. In a subsequent complementary analysis, we investigated the association between fractional anisotropy in the uncinate fasciculus and polygenic risk for bipolar disorder and psychosis in a large cohort (n= 570) of healthy participants. However, we found no significant association.ConclusionsFractional anisotropy in the uncinate fasciculus differs significantly between patients with BD-I and patients with BD-II and healthy controls. This supports the hypothesis of differences in the physiological sub-tract between bipolar disorder subtypes. Similar results were found in unaffected siblings, suggesting the potential for this biomarker to represent an endophenotype for BD-I. However, fractional anisotropy in the uncinate fasciculus seems unrelated to polygenic risk for bipolar disorder or psychosis.Declaration of interestNone.

Styles APA, Harvard, Vancouver, ISO, etc.

5

Coppens, Jeroen R., Kelly B. Mahaney et Saleem I. Abdulrauf. « An anteromedial approach to the temporal horn to avoid injury to the optic radiation fibers and uncinate fasciculus : anatomical and technical note ». Neurosurgical Focus 18, n^o 6 (juin 2005) : 1–6. http://dx.doi.org/10.3171/foc.2005.18.6.16.

Texte intégral

Résumé :

Object The aim of this study was to define an anteromedial approach to the temporal horn via a transsylvian approach to avoid injury to the optic radiation fibers as well as the uncinate fasciculus. This route was compared with standard surgical approaches to the temporal horn, and their relationship to the optic radiation and uncinate fasciculus was reviewed. Methods Three cadaveric brain specimens were prepared with freezing and thawing cycles according to the Klingler technique. Dissection was performed in a lateral-to-medial fashion with the help of wooden spatulas. Photographs were taken through the operating microscope at every level of the dissection. The dissection was continued until the optic radiation was encountered. Particular attention was paid to the relationship of the uncinate fasciculus with the optic radiation. An anteromedial transsylvian approach was defined to enter the temporal horn without injuring the optic radiation or the uncinate fasciculus. Conclusions A transsylvian anteromedial approach through the pyriform cortex at the level of the anterior and superior surface of the uncus enables a safe entry into the temporal horn without injury to the optic radiation fibers or the main part of the uncinate fasciculus.

Styles APA, Harvard, Vancouver, ISO, etc.

6

Incekara, Fatih, Djaina Satoer, Evy Visch-Brink, Arnaud Vincent et Marion Smits. « Changes in language white matter tract microarchitecture associated with cognitive deficits in patients with presumed low-grade glioma ». Journal of Neurosurgery 130, n^o 5 (mai 2019) : 1538–46. http://dx.doi.org/10.3171/2017.12.jns171681.

Texte intégral

Résumé :

OBJECTIVEThe authors conducted a study to determine whether cognitive functioning of patients with presumed low-grade glioma is associated with white matter (WM) tract changes.METHODSThe authors included 77 patients with presumed low-grade glioma who underwent awake surgery between 2005 and 2013. Diffusion tensor imaging with deterministic tractography was performed preoperatively to identify the arcuate, inferior frontooccipital, and uncinate fasciculi and to obtain the mean fractional anisotropy (FA) and mean diffusivity per tract. All patients were evaluated preoperatively using an extensive neuropsychological protocol that included assessments of the language, memory, and attention/executive function domains. Linear regression models were used to analyze each cognitive domain and each diffusion tensor imaging metric of the 3 WM tracts.RESULTSSignificant correlations (corrected for multiple testing) were found between FA of the arcuate fasciculus and results of the repetition test for the language domain (β = 0.59, p < 0.0001) and between FA of the inferior frontooccipital fasciculus and results of the imprinting test for the memory domain (β = −0.55, p = 0.002) and the attention test for the attention and executive function domain (β = −0.62, p = 0.006).CONCLUSIONSIn patients with glioma, language deficits in repetition of speech, imprinting, and attention deficits are associated with changes in the microarchitecture of the arcuate and inferior frontooccipital fasciculi.

Styles APA, Harvard, Vancouver, ISO, etc.

7

Burns, J., D. Job, M. E. Bastin, H. Whalley, T. Macgillivray, E. C. Johnstone et S. M. Lawrie. « Structural disconnectivity in schizophrenia : a diffusion tensor magnetic resonance imaging study ». British Journal of Psychiatry 182, n^o 5 (mai 2003) : 439–43. http://dx.doi.org/10.1192/bjp.182.5.439.

Texte intégral

Résumé :

BackgroundThere is growing evidence that schizophrenia is a disorder of cortical connectivity Specifically, frontotemporal and frontoparietal connections are thought to be functionally impaired. Diffusion tensor magnetic resonance imaging (DT–MRI) is a technique that has the potential to demonstrate structural disconnectivity in schizophrenia.AimsTo investigate the structural integrity of frontotemporal and frontoparietal white matter tracts in schizophrenia.MethodThirty patients with DSM–IV schizophrenia and thirty matched control subjects underwent DT–MRI and structural MRI. Fractional anisotropy – an index of the integrity of white matter tracts – was determined in the uncinate fasciculus, the anterior cingulum and the arcuate fasciculus and analysed using voxel-based morphometry.ResultsThere was reduced fractional anisotropy in the left uncinate fasciculus and left arcuate fasciculus in patients with schizophrenia compared with controls.ConclusionsThe findings of reduced white matter tract integrity in the left uncinate fasciculus and left arcuate fasciculus suggest that there is frontotemporal and frontoparietal structural disconnectivity in schizophrenia.

Styles APA, Harvard, Vancouver, ISO, etc.

8

Charlton, R. A., M. Lamar, A. Zhang, S. Yang, O. Ajilore et A. Kumar. « White-matter tract integrity in late-life depression : associations with severity and cognition ». Psychological Medicine 44, n^o 7 (16 septembre 2013) : 1427–37. http://dx.doi.org/10.1017/s0033291713001980.

Texte intégral

Résumé :

BackgroundAlthough significant changes in both gray and white matter have been noted in late-life depression (LLD), the pathophysiology of implicated white-matter tracts has not been fully described. In this study we examined the integrity of specific white-matter tracts in LLD versus healthy controls (HC).MethodParticipants aged ⩾60 years were recruited from the community. The sample included 23 clinically diagnosed individuals with LLD and 23 HC. White-matter integrity metrics [fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD)] were calculated in the bilateral cingulum and uncinate fasciculus. Depression severity was measured using the Center for Epidemiological Studies Depression Scale (CESD). Composite scores for learning and memory and executive function were created using standardized neuropsychological assessments.ResultsWhite-matter integrity was lower in LLD versus HC in the bilateral cingulum and right uncinate fasciculus (p⩽0.05). In the whole sample, depression severity correlated with integrity in the bilateral cingulum and right uncinate fasciculus (p ⩽0.05). In patients, depression severity correlated with the integrity of the left uncinate fasciculus (p = 0.03); this tract also correlated with executive function (p = 0.02). Among HC, tract integrity did not correlate with depression scores; however, learning and memory correlated with integrity of the bilateral uncinate fasciculus and bilateral cingulum; executive function correlated with the right uncinate and left cingulum (p ⩽0.05).ConclusionsWhite-matter tract integrity was lower in LLD than in HC and was associated with depression severity across all participants. Tract integrity was associated with cognition in both groups but more robustly among HC.

Styles APA, Harvard, Vancouver, ISO, etc.

9

Villegas Martínez, J. L., J. A. Blanco Garrote, F. Uribe Ladrón de Cegama, B. Arribas Simón et G. Cabús Piñol. « Diffusion tensor imaging (DTI) findings in schizophrenia : A review ». European Psychiatry 26, S2 (mars 2011) : 960. http://dx.doi.org/10.1016/s0924-9338(11)72665-7.

Texte intégral

Résumé :

IntroductionDiffusion tensor imaging (DTI) is a magnetic resonance imaging technique that have increasingly being used for the non-invasive evaluation of brain white matter (WM) abnormalities. Several studies suggest that the normal integration of cerebral function may be compromised in schizophrenia. Abnormalities in WM tracts may be directly relevant for the neuropathology of schizophrenia.ObjetivesThe purpose of this review was to discuss recent DTI findings in schizophrenia and a methodologic analysis.MethodsThe literature search was performed with the search engine PubMed of the U.S. National Library of Medicine. Search strategy used was based on the Cochrane review technique, limited to the period between 1998 (first report on DTI and schizophrenia) and May 2010. And limited to ‘Title/Abstract’. The reference lists of these studies were used to identify additional studies.ResultsThere is a striking amount of heterogeneity in findings, probably by methodologic problems. Brain regions such as the cingulate bundle, corpus callosum, and regions within frontal and temporal WM have a proportionally larger number of positive findings across the studies. In addition, WM tracts as The superior longitudinal fasciculus, fronto-occipital longitudinal fasciculi, uncinate fasciculi, frontal longitudinal fasciculus and the arcuate fasciculus have also positive findings in patients with schizophrenia. Other brain structures as the cerebellar peduncles, the fornix, the hippocampus and parahippocampal gyrus, the thalamic and optic radiations have been evaluated and shown positive findings. However, these findings are not present in all studies. DTI abnormalities in first-episode patients are less robust than in chronic patients.ConclusionsRecent DTI findings further support the hypothesis of structural dysconnectivity in schizophrenia.

Styles APA, Harvard, Vancouver, ISO, etc.

10

Sundram, F., Q. Deeley, S. Sarkar, E. Daly, R. Latham, G. J. Barker et D. G. M. Murphy. « P02 - 361 White matter microstructural abnormalities in antisocial personality disorder : A pilot diffusion tensor imaging study ». European Psychiatry 26, S2 (mars 2011) : 957. http://dx.doi.org/10.1016/s0924-9338(11)72662-1.

Texte intégral

Résumé :

IntroductionAntisocial personality disorder (ASPD) and psychopathy involve significant interpersonal and behavioural impairments. However, little is known about white matter (WM) abnormalities in tracts linking grey matter regions. A previous diffusion tensor imaging (DT-MRI) tractography study in ASPD and psychopathy revealed abnormalities in the right uncinate fasciculus, indicating fronto-limbic disconnectivity.ObjectivesIt is not clear whether WM abnormalities are restricted to only this tract or are more widespread. Therefore, we planned to use whole brain DT-MRI voxel-based analyses.AimsTo clarify if WM abnormalities extend beyond the frontal lobe.MethodsWe used whole brain DT-MRI to compare WM fractional anisotropy (FA) of 15 adults with ASPD and healthy age, handedness and IQ-matched controls. Also, within ASPD subjects, we related differences in FA to severity of psychopathy measures.ResultsSignificant WM FA reductions were found in ASPD subjects relative to controls. These were found bilaterally in the anterior corpus callosum. Right hemisphere FA reduction was found in the anterior corona radiata, uncinate fasciculus, inferior fronto-occipital fasciculus and internal capsule. Left hemisphere, FA deficits encompassed the inferior longitudinal fasciculus, inferior fronto-occipital fasciculus and internal capsule. There was a significant negative correlation between WM FA in the right uncinate fasciculus and corpus callosum and measures of psychopathy.ConclusionsWe report FA reduction in the uncinate fasciculus and anterior corpus callosum which may be associated with frontal and inter-hemispheric disconnectivity in ASPD, in addition to abnormalities in other tracts which directly or indirectly connect to prefrontal regions.

Styles APA, Harvard, Vancouver, ISO, etc.

11

Hula, William D., Sandip Panesar, Michelle L. Gravier, Fang-Cheng Yeh, Haley C. Dresang, Michael Walsh Dickey et Juan C. Fernandez-Miranda. « Structural white matter connectometry of word production in aphasia : an observational study ». Brain 143, n^o 8 (23 juillet 2020) : 2532–44. http://dx.doi.org/10.1093/brain/awaa193.

Texte intégral

Résumé :

Abstract While current dual-steam neurocognitive models of language function have coalesced around the view that distinct neuroanatomical networks subserve semantic and phonological processing, respectively, the specific white matter components of these networks remain a matter of debate. To inform this debate, we investigated relationships between structural white matter connectivity and word production in a cross-sectional study of 42 participants with aphasia due to unilateral left hemisphere stroke. Specifically, we reconstructed a local connectome matrix for each participant from diffusion spectrum imaging data and regressed these matrices on indices of semantic and phonological ability derived from their responses to a picture-naming test and a computational model of word production. These connectometry analyses indicated that both dorsally located (arcuate fasciculus) and ventrally located (inferior frontal-occipital, uncinate, and middle longitudinal fasciculi) tracts were associated with semantic ability, while associations with phonological ability were more dorsally situated, including the arcuate and middle longitudinal fasciculi. Associations with limbic pathways including the posterior cingulum bundle and the fornix were also found. All analyses controlled for total lesion volume and all results showing positive associations obtained false discovery rates < 0.05. These results challenge dual-stream accounts that deny a role for the arcuate fasciculus in semantic processing, and for ventral-stream pathways in language production. They also illuminate limbic contributions to both semantic and phonological processing for word production.

Styles APA, Harvard, Vancouver, ISO, etc.

12

Lischke, A., M. Domin, H. J. Freyberger, H. J. Grabe, R. Mentel, D. Bernheim et M. Lotze. « Structural alterations in white-matter tracts connecting (para-)limbic and prefrontal brain regions in borderline personality disorder ». Psychological Medicine 45, n^o 15 (19 juin 2015) : 3171–80. http://dx.doi.org/10.1017/s0033291715001142.

Texte intégral

Résumé :

BackgroundA dysfunctional network of prefrontal and (para-)limbic brain region has been suggested to underlie emotional dysregulation in borderline personality disorder (BPD). Abnormal activity in this network may be due to structural alterations in white-matter tracts connecting prefrontal and (para-)limbic brain regions. To test this hypothesis, we investigated the structural integrity of major white-matter tracts connecting these regions in BPD.MethodUsing diffusion tensor imaging, we investigated fractional anisotropy (FA), axonal anisotropy (AD) and radial diffusivity (RD) in the uncinate fasciculus, the major white-matter tract connecting (para-)limbic and prefrontal brain regions, in 26 healthy controls (HC) and 26 BPD participants. To clarify the specificity of possible white-matter alterations among HC and BPD participants, FA, AD and RD were also investigated in the cingulum.ResultsWe found distinct structural alterations in the uncinate fasciculus but not in the cingulum of BPD participants. Compared to HC participants, BPD participants showed lower FA and higher RD in the uncinate fasciculus. By contrast, AD did not differ in the uncinate fasciculus of HC and BPD participants.ConclusionsOur finding of abnormal FA and RD in the uncinate fasciculus indicates distinct white-matter alterations in BPD, presumably due to stress-induced myelin degeneration in the aftermath of stressful life events. Although these alterations may account for abnormal activity in brain regions implicated in emotion dysregulation, such as the amygdala, anterior cingulate cortex and prefrontal cortex, it remains to be determined whether these alterations are specific for BPD.

Styles APA, Harvard, Vancouver, ISO, etc.

13

Kierońska, Sara, Milena Świtońska, Grzegorz Meder, Magdalena Piotrowska et Paweł Sokal. « Tractography Alterations in the Arcuate and Uncinate Fasciculi in Post-Stroke Aphasia ». Brain Sciences 11, n^o 1 (5 janvier 2021) : 53. http://dx.doi.org/10.3390/brainsci11010053.

Texte intégral

Résumé :

Fiber tractography based on diffuse tensor imaging (DTI) can reveal three-dimensional white matter connectivity of the human brain. Tractography is a non-invasive method of visualizing cerebral white matter structures in vivo, including neural pathways surrounding the ischemic area. DTI may be useful for elucidating alterations in brain connectivity resulting from neuroplasticity after stroke. We present a case of a male patient who developed significant mixed aphasia following ischemic stroke. The patient had been treated by mechanical thrombectomy followed by an early rehabilitation, in conjunction with transcranial direct current stimulation (tDCS). DTI was used to examine the arcuate fasciculus and uncinate fasciculus upon admission and again at three months post-stroke. Results showed an improvement in the patient’s symptoms of aphasia, which was associated with changes in the volume and numbers of tracts in the uncinate fasciculus and the arcuate fasciculus.

Styles APA, Harvard, Vancouver, ISO, etc.

14

Koch, Saskia B. J., Mirjam van Zuiden, Laura Nawijn, Jessie L. Frijling, Dick J. Veltman et Miranda Olff. « Decreased uncinate fasciculus tract integrity in male ». Journal of Psychiatry & ; Neuroscience 42, n^o 5 (1 septembre 2017) : 331–42. http://dx.doi.org/10.1503/jpn.160129.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

15

Ribas, Eduardo Carvalhal, Kaan Yagmurlu, Hung Tzu Wen et Albert L. Rhoton. « Microsurgical anatomy of the inferior limiting insular sulcus and the temporal stem ». Journal of Neurosurgery 122, n^o 6 (juin 2015) : 1263–73. http://dx.doi.org/10.3171/2014.10.jns141194.

Texte intégral

Résumé :

OBJECT The purpose of this study was to describe the location of each white matter pathway in the area between the inferior limiting insular sulcus (ILS) and temporal horn that may be crossed in approaches through the temporal stem to the medial temporal lobe. METHODS The fiber tracts in 14 adult cadaveric cerebral hemispheres were examined using the Klingler technique. The fiber dissections were completed in a stepwise manner, identifying each white matter pathway in different planes and describing its position in relation to the anterior end of the ILS. RESULTS The short-association fibers from the extreme capsule, which continue toward the operculae, are the most superficial subcortical layer deep to the ILS. The external capsule fibers are found deeper at an intermediate layer and are formed by the uncinate fasciculus, inferior frontooccipital fasciculus, and claustrocortical fibers in a sequential anteroposterior disposition. The anterior commissure forms the next deeper layer, and the optic radiations in the sublenticular part of the internal capsule represent the deepest layer. The uncinate fasciculus is found deep to the anterior third of the ILS, whereas the inferior frontooccipital fasciculus and optic radiations are found superficial and deep, respectively, at the posterior two-thirds of this length. CONCLUSIONS The authors' findings suggest that in the transsylvian approach, a 6-mm incision beginning just posterior to the limen insula through the ILS will cross the uncinate fasciculus but not the inferior frontooccipital fasciculus or optic radiations, but that longer incisions carry a risk to language and visual functions.

Styles APA, Harvard, Vancouver, ISO, etc.

16

Liu, Duan, Zan Wang, Hao Shu et Zhijun Zhang. « Disrupted white matter integrity is associated with cognitive deficits in patients with amnestic mild cognitive impairment : An atlas-based study ». SAGE Open Medicine 4 (1 janvier 2016) : 205031211664881. http://dx.doi.org/10.1177/2050312116648812.

Texte intégral

Résumé :

Objective: This study investigated white matter integrity in patients with amnestic mild cognitive impairment by diffusion tensor imaging. Methods: A total of 83 patients with amnestic mild cognitive impairment and 85 elderly healthy controls underwent neuropsychological testing and a diffusion tensor imaging scan. Whole-brain white matter data were parcellated into 50 regions based on the anatomical ICBM-DTI-81 atlas, and regional diffusion metrics consisting of fractional anisotropy, mean diffusivity, radial diffusivity, and axial diffusivity were calculated for each region. Diffusion tensor imaging indices were compared between groups, and it was determined that between-group differences were significantly correlated with neurocognitive performance. Results: Relative to the healthy controls group, the amnestic mild cognitive impairment group exhibited poorer cognitive performance in all neuropsychological tests except the complex figure test ( p = 0.083) and showed decreased mean fractional anisotropy in the fornix, increased mean diffusivity in the fornix and bilateral uncinate fasciculus, elevated axial diffusivity in the fornix and genu of corpus callosum, and elevated radial diffusivity in the fornix and bilateral uncinate fasciculus ( p < 0.05). Behaviorally, integrity of the bilateral uncinate fasciculus was correlated positively with episodic memory function, while left uncinate fasciculus integrity was positively associated with language function in the amnestic mild cognitive impairment group ( p < 0.05). Conclusion: White matter abnormalities in neural pathways associated with memory were correlated with neurocognitive deficiencies in amnestic mild cognitive impairment. Given that amnestic mild cognitive impairment is putatively a prodromal syndrome for Alzheimer’s disease, this study furthers our understanding of the white matter changes associated with Alzheimer’s disease pathogenesis in the predementia stage.

Styles APA, Harvard, Vancouver, ISO, etc.

17

Ansari, Mina, Sahand Adib Moradi, Farzaneh Ghazi Sherbaf, Abozar Hedayatnia et Mohammad Hadi Aarabi. « Comparison of structural connectivity in Parkinson's disease with depressive symptoms versus non-depressed : a diffusion MRI connectometry study ». International Psychogeriatrics 31, n^o 1 (21 mars 2018) : 5–12. http://dx.doi.org/10.1017/s1041610218000170.

Texte intégral

Résumé :

ABSTRACTObjective:Research on psychobiological markers of Parkinson's disease (PD) remains a hot topic. Non-motor symptoms such as depression and REM sleep behavior disorder (RBD) each attribute to a particular neurodegenerative cluster in PD, and might enlighten the way for early prediction/detection of PD. The neuropathology of mood disturbances remains unclear. In fact, a few studies have investigated depression using diffusion magnetic resonance imaging (diffusion MRI).Method:Diffusion MRI of PD patients without comorbid RBD was used to assess whether microstructural abnormalities are detectable in the brain of 40 PD patients with depression compared to 19 patients without depression. Diffusion MRI connectometry was used to carry out group analysis between age- and gender-matched PD patients with and without depressive symptoms. Diffusion MRI connectometry is based on spin distribution function, which quantifies the density of diffusing water and is a sensitive and specific analytical method to psychological differences between groups.Results:A significant difference (FDR = 0.016129) was observed in the left and right uncinate fasciculi, left and right inferior longitudinal fasciculi, left and right fornices, left inferior fronto-occipital fasciculus, right corticospinal tract, genu of corpus callosum, and middle cerebellar peduncle.Conclusion:These results suggest the prominent circuits involved in emotion recognition, particularly negative emotions, might be impaired in comorbid depressive symptoms in PD.

Styles APA, Harvard, Vancouver, ISO, etc.

18

Salvati, Luca Francesco, Raffaele De Marco, Giuseppe Palmieri, Massimiliano Minardi, Armando Massara, Alessandro Pesaresi, Bernarda Cagetti, Antonio Melcarne et Diego Garbossa. « The Relevant Role of Navigated Tractography in Speech Eloquent Area Glioma Surgery : Single Center Experience ». Brain Sciences 11, n^o 11 (28 octobre 2021) : 1436. http://dx.doi.org/10.3390/brainsci11111436.

Texte intégral

Résumé :

Background: Gliomas are among the most challenging pathologies for neurosurgeons due to their infiltrative and recurrent nature in functionally relevant regions. Current knowledge confirms that gross total resection highly influence survival in patient with glioma. However, surgery performed in eloquent brain area, could seriously compromise the quality of life in patient with reduced life expectancy even more if it concerns the language function. Methods: 18 right-handed patients with perisylvian gliomas on the left hemisphere were prospectively analyzed over a period of 12 months. Standardized preoperative Diffusion-Tensor-Imaging based tractography of the five main language Tracts (Arcuate Fasciculus, Frontal Aslant Tract, Inferior Fronto-Occipital Fasciculus, Inferior Longitudinal Fasciculus, Uncinate Fasciculus) was navigated during the surgical procedure. Using a validated method, correlations were made between the pre-operative fascicles and their possible infiltration and surgical damage. The language status was assessed using the Aachen Aphasia Test. Results: In all nine patients who developed a permanent disorder there was pre-operative involvement of at least one fascicle and resection of at least one of these. In this way, areas of high risk of permanent language damage have emerged as a result of surgical injury: the temporoparietal junction, the middle portion of the FAT and the temporal stem. Conclusions: Navigated tractography has proven to be a user-friendly tool that can assess perioperative risk, guide surgical resection, and help the neurosurgeon to find that balance between tumor resection and function preservation.

Styles APA, Harvard, Vancouver, ISO, etc.

19

Serpa, M. H., J. Doshi, G. Erus, T. M. Chaim-Avancini, M. Cavallet, M. T. van de Bilt, P. C. Sallet et al. « State-dependent microstructural white matter changes in drug-naïve patients with first-episode psychosis ». Psychological Medicine 47, n^o 15 (22 août 2017) : 2613–27. http://dx.doi.org/10.1017/s0033291717001015.

Texte intégral

Résumé :

BackgroundDiffusion tensor imaging (DTI) studies have consistently shown white matter (WM) microstructural abnormalities in schizophrenia. Whether or not such alterations could vary depending on clinical status (i.e. acute psychosis v. remission) remains to be investigated.MethodsTwenty-five treatment-naïve first-episode psychosis (FEP) patients and 51 healthy-controls (HC) underwent MRI scanning at baseline. Twenty-one patients were re-scanned as soon as they achieved sustained remission of symptoms; 36 HC were also scanned twice. Rate-of-change maps of longitudinal DTI changes were calculated for in order to examine WM alterations associated with changes in clinical status. We conducted voxelwise analyses of fractional anisotropy (FA) and trace (TR) maps.ResultsAt baseline, FEP presented reductions of FA in comparison with HC [p < 0.05, false-discovery rate (FDR)-corrected] affecting fronto-limbic WM and associative, projective and commissural fasciculi. After symptom remission, patients showed FA increase over time (p < 0.001, uncorrected) in some of the above WM tracts, namely the right anterior thalamic radiation, right uncinate fasciculus/inferior fronto-occipital fasciculus, and left inferior fronto-occipital fasciculus/inferior longitudinal fasciculus. We also found significant correlations between reductions in PANSS scores and FA increases over time (p < 0.05, FDR-corrected).ConclusionsWM changes affecting brain tracts critical to the integration of perceptual information, cognition and emotions are detectable soon after the onset of FEP and may partially reverse in direct relation to the remission of acute psychotic symptoms. Our findings reinforce the view that WM abnormalities in brain tracts are a key neurobiological feature of acute psychotic disorders, and recovery from such WM pathology can lead to amelioration of symptoms.

Styles APA, Harvard, Vancouver, ISO, etc.

20

Riggs, Lily, Eric Bouffet, Suzanne Laughlin, Normand Laperriere, Fang Liu, Jovanka Skocic, Nadia Scantlebury et al. « Changes to Memory Structures in Children Treated for Posterior Fossa Tumors ». Journal of the International Neuropsychological Society 20, n^o 2 (24 janvier 2014) : 168–80. http://dx.doi.org/10.1017/s135561771300129x.

Texte intégral

Résumé :

AbstractChildren treated for medulloblastoma (MB) exhibit long-term impairments in declarative memory, but the pathophysiology underlying this is unclear. Previous studies report declines in global white matter volume, but have failed to link this to declines in memory performance. We examined the effects of treatment on measures ofglobalbrain structure (i.e., total white and gray matter volume) andspecificmemory structures (i.e., hippocampus and uncinate fasciculus). We used volumetric MRI and diffusion tensor imaging in pediatric survivors of MB and one survivor of astrocytoma treated with cranial-spinal radiation (n= 20), and healthy controls (n= 13). Compared to controls, the survivor group exhibited reduced white matter volume, damage to the uncinate fasciculus, and a smaller right hippocampus. Critically, reduced hippocampal volume was not related to differences in brain volume, suggesting that the hippocampus may be especially vulnerable to treatment effects. A subset of the survivors (n= 10) also underwent memory testing using the Children's Memory Scale (CMS). Performance on the general index of the CMS was significantly correlated with measures of hippocampal volume and uncinate fasciculus. The examination of treatment effects on specific brain regions provides a better understanding of long-term cognitive outcome in children with brain tumors, particularly medulloblastoma. (JINS, 2014,1, 1–13)

Styles APA, Harvard, Vancouver, ISO, etc.

21

Tröstl, J., R. Sladky, A. Hummer, C. Kraus, E. Moser, S. Kasper, R. Lanzenberger et C. Windischberger. « Reduced connectivity in the uncinate fiber tract between the frontal cortex and limbic subcortical areas in social phobia ». European Psychiatry 26, S2 (mars 2011) : 182. http://dx.doi.org/10.1016/s0924-9338(11)71893-4.

Texte intégral

Résumé :

IntroductionSeveral fMRI and resting-state connectivity studies have demonstrated alterations in the limbic system and frontal areas in social anxiety disorder (SAD).AimsHere we used high-resolution whole-brain diffusion tensor imaging (DTI) to examine differences in anatomical connectivity between patients and controls in the white matter.MethodsWe examined 14 SAD patients (age 26.3 ± 9.0y) and 15 healthy controls (age 25.6 ± 3.3y) using DTI on a 3T Trio MRI scanner (Siemens, Germany). DTI acquisition with 1.6 mm isotropic resolution was performed in 30 directions and a maximum b-value of 800. Fractional anisotropy (FA) maps were obtained using FSL. Group analysis was performed in SPM8 (two sample t-test).ResultsThe figure shows a coronal slice through the uncinate fasciculus. Arrows point to areas where SAD patients show decreased FA-values compared to controls (p < 0.05). Note that these areas are limited to the uncinate fasciculus and are found bilaterally.ConclusionReduced FA-values indicate a reduction in anatomical connectivity strength. Our study thus clearly shows reduced connectivity strength in the uncinate fasciculus connecting frontal regions with limbic areas as the amygdalae and hippocampus. This reduced structural connectivity supports functional data demonstrating alterations of brain activation in the amygdala and prefrontal regions in social phobia.

Styles APA, Harvard, Vancouver, ISO, etc.

22

Kircanski, Katharina, Lucinda M. Sisk, Tiffany C. Ho, Kathryn L. Humphreys, Lucy S. King, Natalie L. Colich, Sarah J. Ordaz et Ian H. Gotlib. « Early life stress, cortisol, frontolimbic connectivity, and depressive symptoms during puberty ». Development and Psychopathology 31, n^o 3 (8 mai 2019) : 1011–22. http://dx.doi.org/10.1017/s0954579419000555.

Texte intégral

Résumé :

AbstractEarly life stress (ELS) is a risk factor for the development of depression in adolescence; the mediating neurobiological mechanisms, however, are unknown. In this study, we examined in early pubertal youth the associations among ELS, cortisol stress responsivity, and white matter microstructure of the uncinate fasciculus and the fornix, two key frontolimbic tracts; we also tested whether and how these variables predicted depressive symptoms in later puberty. A total of 208 participants (117 females; M age = 11.37 years; M Tanner stage = 2.03) provided data across two or more assessment modalities: ELS; salivary cortisol levels during a psychosocial stress task; diffusion magnetic resonance imaging; and depressive symptoms. In early puberty there were significant associations between higher ELS and decreased cortisol production, and between decreased cortisol production and increased fractional anisotropy in the uncinate fasciculus. Further, increased fractional anisotropy in the uncinate fasciculus predicted higher depressive symptoms in later puberty, above and beyond earlier symptoms. In post hoc analyses, we found that sex moderated several additional associations. We discuss these findings within a broader conceptual model linking ELS, emotion dysregulation, and depression across the transition through puberty, and contend that brain circuits implicated in the control of hypothalamic–pituitary–adrenal axis function should be a focus of continued research.

Styles APA, Harvard, Vancouver, ISO, etc.

23

Olson, Elizabeth A., Paul F. Collins, Catalina J. Hooper, Ryan Muetzel, Kelvin O. Lim et Monica Luciana. « White Matter Integrity Predicts Delay Discounting Behavior in 9- to 23-Year-Olds : A Diffusion Tensor Imaging Study ». Journal of Cognitive Neuroscience 21, n^o 7 (juillet 2009) : 1406–21. http://dx.doi.org/10.1162/jocn.2009.21107.

Texte intégral

Résumé :

Healthy participants (n = 79), ages 9–23, completed a delay discounting task assessing the extent to which the value of a monetary reward declines as the delay to its receipt increases. Diffusion tensor imaging (DTI) was used to evaluate how individual differences in delay discounting relate to variation in fractional anisotropy (FA) and mean diffusivity (MD) within whole-brain white matter using voxel-based regressions. Given that rapid prefrontal lobe development is occurring during this age range and that functional imaging studies have implicated the prefrontal cortex in discounting behavior, we hypothesized that differences in FA and MD would be associated with alterations in the discounting rate. The analyses revealed a number of clusters where less impulsive performance on the delay discounting task was associated with higher FA and lower MD. The clusters were located primarily in bilateral frontal and temporal lobes and were localized within white matter tracts, including portions of the inferior and superior longitudinal fasciculi, anterior thalamic radiation, uncinate fasciculus, inferior fronto-occipital fasciculus, corticospinal tract, and splenium of the corpus callosum. FA increased and MD decreased with age in the majority of these regions. Some, but not all, of the discounting/DTI associations remained significant after controlling for age. Findings are discussed in terms of both developmental and age-independent effects of white matter organization on discounting behavior.

Styles APA, Harvard, Vancouver, ISO, etc.

24

Lauro, Leonor Josefina Romero, Christiano Miracapillo, Alessandra Casarotti, Lorenzo Bello et Costanza Papagno. « What is the Role of the Uncinate Fasciculus ? » Procedia - Social and Behavioral Sciences 6 (2010) : 84–85. http://dx.doi.org/10.1016/j.sbspro.2010.08.043.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

25

Duffau, H., P. Gatignol, S. Moritz-Gasser et E. Mandonnet. « Is the left uncinate fasciculus essential for language ? » Journal of Neurology 256, n^o 3 (mars 2009) : 382–89. http://dx.doi.org/10.1007/s00415-009-0053-9.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

26

Liu, Xiaodan, Keita Watanabe, Shingo Kakeda, Reiji Yoshimura, Osamu Abe, Satoru Ide, Kenji Hayashi et al. « Relationship between white matter integrity and serum cortisol levels in drug-naive patients with major depressive disorder : Diffusion tensor imaging study using tract-based spatial statistics ». British Journal of Psychiatry 208, n^o 6 (juin 2016) : 585–90. http://dx.doi.org/10.1192/bjp.bp.114.155689.

Texte intégral

Résumé :

BackgroundHigher daytime cortisol levels because of a hyperactive hypothalamic–pituitary–adrenal axis have been reported in patients with major depressive disorder (MDD). The elevated glucocorticoids inhibit the proliferation of the oligodendrocytes that are responsible for myelinating the axons of white matter fibre tracts.AimsTo evaluate the relationship between white matter integrity and serum cortisol levels during a first depressive episode in drug-naive patients with MDD (MDD group) using a tract-based spatial statistics (TBSS) method.MethodThe MDD group (n = 29) and a healthy control group (n = 47) underwent diffusion tensor imaging (DTI) scans and an analysis was conducted using TBSS. Morning blood samples were obtained from both groups for cortisol measurement.ResultsCompared with the controls, the MDD group had significantly reduced fractional anisotropy values (P<0.05, family-wise error (FWE)-corrected) in the inferior fronto-occipital fasciculus, uncinate fasciculus and anterior thalamic radiation. The fractional anisotropy values of the inferior fronto-occipital fasciculus, uncinate fasciculus and anterior thalamic radiation had significantly negative correlations with the serum cortisol levels in the MDD group (P<0.05, FWE-corrected).ConclusionsOur findings indicate that the elevated cortisol levels in the MDD group may injure the white matter integrity in the frontal–subcortical and frontal–limbic circuits.

Styles APA, Harvard, Vancouver, ISO, etc.

27

Breeden, A. L., E. M. Cardinale, L. M. Lozier, J. W. VanMeter et A. A. Marsh. « Callous-unemotional traits drive reduced white-matter integrity in youths with conduct problems ». Psychological Medicine 45, n^o 14 (19 juin 2015) : 3033–46. http://dx.doi.org/10.1017/s0033291715000987.

Texte intégral

Résumé :

Background.Callous-unemotional (CU) traits represent a significant risk factor for severe and persistent conduct problems in children and adolescents. Extensive neuroimaging research links CU traits to structural and functional abnormalities in the amygdala and ventromedial prefrontal cortex. In addition, adults with psychopathy (a disorder for which CU traits are a developmental precursor) exhibit reduced integrity in uncinate fasciculus, a white-matter (WM) tract that connects prefrontal and temporal regions. However, research in adolescents has not yet yielded similarly consistent findings.Method.We simultaneously modeled CU traits and externalizing behaviors as continuous traits, while controlling for age and IQ, in order to identify the unique relationship of each variable with WM microstructural integrity, assessed using diffusion tensor imaging. We used tract-based spatial statistics to evaluate fractional anisotropy, an index of WM integrity, in uncinate fasciculus and stria terminalis in 47 youths aged 10–17 years, of whom 26 exhibited conduct problems and varying levels of CU traits.Results.Whereas both CU traits and externalizing behaviors were negatively correlated with WM integrity in bilateral uncinate fasciculus and stria terminalis/fornix, simultaneously modeling both variables revealed that these effects were driven by CU traits; the severity of externalizing behavior was not related to WM integrity after controlling for CU traits.Conclusions.These results indicate that WM abnormalities similar to those observed in adult populations with psychopathy may emerge in late childhood or early adolescence, and may be critical to understanding the social and affective deficits observed in this population.

Styles APA, Harvard, Vancouver, ISO, etc.

28

Von Der Heide, Rebecca J., Laura M. Skipper, Elizabeth Klobusicky et Ingrid R. Olson. « Dissecting the uncinate fasciculus : disorders, controversies and a hypothesis ». Brain 136, n^o 6 (6 mai 2013) : 1692–707. http://dx.doi.org/10.1093/brain/awt094.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

29

Di Tella, Sonia, Francesca Baglio, Laura Pelizzari, Monia Cabinio, Raffaello Nemni, Daniela Traficante et Maria Caterina Silveri. « Uncinate fasciculus and word selection processing in Parkinson's disease ». Neuropsychologia 146 (septembre 2020) : 107504. http://dx.doi.org/10.1016/j.neuropsychologia.2020.107504.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

30

Martino, Juan, David Mato, Enrique Marco de Lucas, Juan A. García-Porrero, Andreu Gabarrós, Alejandro Fernández-Coello et Alfonso Vázquez-Barquero. « Subcortical anatomy as an anatomical and functional landmark in insulo-opercular gliomas : implications for surgical approach to the insular region ». Journal of Neurosurgery 123, n^o 4 (octobre 2015) : 1081–92. http://dx.doi.org/10.3171/2014.11.jns141992.

Texte intégral

Résumé :

OBJECT Little attention has been given to the functional challenges of the insular approach to the resection of gliomas, despite the potential damage of essential neural networks that underlie the insula. The object of this study is to analyze the subcortical anatomy of the insular region when infiltrated by gliomas, and compare it with the normal anatomy in nontumoral hemispheres. METHODS Ten postmortem human hemispheres were dissected, with isolation of the inferior fronto-occipital fasciculus (IFOF) and the uncinate fasciculus. Probabilistic diffusion tensor imaging (DTI) tractography was used to analyze the subcortical anatomy of the insular region in 10 healthy volunteers and in 22 patients with insular Grade II and Grade III gliomas. The subcortical anatomy of the insular region in these 22 insular gliomas was compared with the normal anatomy in 20 nontumoral hemispheres. RESULTS In tumoral hemispheres, the distances between the peri-insular sulci and the lateral surface of the IFOF and uncinate fasciculus were enlarged (p < 0.05). Also in tumoral hemispheres, the IFOF was identified in 10 (90.9%) of 11 patients with an extent of resection less than 80%, and in 4 (36.4%) of 11 patients with an extent of resection equal to or greater than 80% (multivariate analysis: p = 0.03). CONCLUSIONS Insular gliomas grow in the space between the lateral surface of the IFOF and uncinate fasciculus and the insular surface, displacing and compressing the tracts medially. Moreover, these tracts may be completely infiltrated by the tumor, with a total disruption of the bundles. In the current study, the identification of the IFOF with DTI tractography was significantly associated with the extent of tumor resection. If the IFOF is not identified preoperatively, there is a high probability of achieving a resection greater than 80%.

Styles APA, Harvard, Vancouver, ISO, etc.

31

Hanson, Jamie L., Annchen R. Knodt, Bartholomew D. Brigidi et Ahmad R. Hariri. « Lower structural integrity of the uncinate fasciculus is associated with a history of child maltreatment and future psychological vulnerability to stress ». Development and Psychopathology 27, n^o 4pt2 (novembre 2015) : 1611–19. http://dx.doi.org/10.1017/s0954579415000978.

Texte intégral

Résumé :

AbstractThe experience of child maltreatment is a significant risk factor for the development of later internalizing disorders such as depression and anxiety. This risk is particularly heightened after exposure to additional, more contemporaneous stress. While behavioral evidence exists for such “stress sensitization,” little is known about the mechanisms mediating such relationships, particularly within the brain. Here we report that the experience of child maltreatment independent of recent life stress, gender, and age is associated with reduced structural integrity of the uncinate fasciculus, a major white matter pathway between the amygdala and ventromedial prefrontal cortex, in young adults. We further demonstrate that individuals with lower uncinate fasciculus integrity at baseline who subsequently experience stressful life events report higher levels of internalizing symptomatology at follow-up. Our findings suggest a novel neurobiological mechanism linking child maltreatment with later internalizing symptoms, specifically altered structural connectivity within the brain's threat-detection and emotion-regulation circuitry.

Styles APA, Harvard, Vancouver, ISO, etc.

32

Luttenbacher, I., A. Philips, R. Kazemi, A. Hadipour, I. Sanghvi, J. Martinez et M. Adamson. « Transdiagnostic Role of Glutamate and White Matter Damage in Neuropsychiatric Disorders : A Systematic Review ». European Psychiatry 65, S1 (juin 2022) : S164—S165. http://dx.doi.org/10.1192/j.eurpsy.2022.440.

Texte intégral

Résumé :

Introduction Neuropsychiatric disorders including Generalized Anxiety Disorder (GAD), Obsessive-Compulsive Disorder (OCD), Major Depressive Disorder (MDD), Bipolar Disorder (BD), and Schizophrenia (SZ) have been considered distinct categories of diseases despite their overlapping characteristics and symptomatology. Objectives We aimed to provide an in-depth review elucidating the role of glutamate/Glx and white matter (WM) abnormalities from a transdiagnostic perspective. Methods The PubMed online database was searched for studies published between 2010 and 2021. After careful screening, 399 studies were included. Results The findings point to decreased levels of glutamate in the Anterior Cingulate Cortex in both SZ and BD, whereas Glx is elevated in the Hippocampus in SZ and MDD. With regard to WM abnormalities, the Corpus Callosum and superior Longitudinal Fascicle were the most consistently identified brain regions showing decreased fractional anisotropy (FA) across all the reviewed disorders, except GAD. Additionally, the Uncinate Fasciculus was found to be affected in all the reviewed disorders, except OCD. Decreased FA was also found in the inferior Longitudinal Fasciculus, inferior Fronto-Occipital Fasciculus, Thalamic Radiation, and Corona Radiata in SZ, BD, and MDD. Decreased FA in the Fornix and Corticospinal Tract were found in BD and SZ patients. The Cingulum and Anterior Limb of Internal Capsule exhibited decreased FA in MDD and SZ patients. Conclusions The results suggest a gradual increase in severity from GAD to SZ defined by the number of brain regions with WM abnormality which may be partially caused by abnormal glutamate levels. WM damage could thus be considered a potential marker of some of the main neuropsychiatric disorders. Disclosure No significant relationships.

Styles APA, Harvard, Vancouver, ISO, etc.

33

Linke, Julia O. « The Uncinate Fasciculus in Anxiety Disorders : A Potential Treatment Target ? » Biological Psychiatry 86, n^o 12 (décembre 2019) : e47-e48. http://dx.doi.org/10.1016/j.biopsych.2019.09.020.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

34

Oishi, Kenichi, Andreia V. Faria, John Hsu, Donna Tippett, Susumu Mori et Argye E. Hillis. « Critical role of the right uncinate fasciculus in emotional empathy ». Annals of Neurology 77, n^o 1 (21 novembre 2014) : 68–74. http://dx.doi.org/10.1002/ana.24300.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

35

Borges, Kellen Christina Malheiros, Hisao Nishijo, Tales Alexandre Aversi-Ferreira, Jussara Rocha Ferreira et Leonardo Ferreira Caixeta. « Anatomical Study of Intrahemispheric Association Fibers in the Brains of Capuchin Monkeys (Sapajussp.) ». BioMed Research International 2015 (2015) : 1–6. http://dx.doi.org/10.1155/2015/648128.

Texte intégral

Résumé :

Previous studies suggest that the complexity of fiber connections in the brain plays a key role in the evolutionary process of the primate brain and behaviors. The patterns of brain fiber systems have been studied in detail in many nonhuman primates, but not inSapajussp. Behavioral studies indicated thatSapajussp. (bearded capuchins) show highly cognitive behaviors such as tool use comparable to those in other nonhuman primates. To compare the brain fiber systems in capuchins with those in other nonhuman primates and humans, the intrahemispheric fibers systems in 24 cerebral hemispheres ofSapajuswere dissected by a freezing-thawing procedure. Dissection of the hemispheres in lateral view indicated short arcuate fibers, uncinate fasciculus, and inferior longitudinal fasciculus, while that in a medial view indicated short arcuate fibers, the cingulum united with the superior longitudinal fasciculus, and inferior longitudinal fasciculus. The results showed that the fiber systems inSapajusare comparable to those in rhesus and humans, except for a lack of independent superior longitudinal fasciculus and cingulum inSapajus.

Styles APA, Harvard, Vancouver, ISO, etc.

36

McKenna, Benjamin S., Rebecca J. Theilmann, Ashley N. Sutherland et Lisa T. Eyler. « Fusing Functional MRI and Diffusion Tensor Imaging Measures of Brain Function and Structure to Predict Working Memory and Processing Speed Performance among Inter-episode Bipolar Patients ». Journal of the International Neuropsychological Society 21, n^o 5 (mai 2015) : 330–41. http://dx.doi.org/10.1017/s1355617715000314.

Texte intégral

Résumé :

AbstractEvidence for abnormal brain function as measured with diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI) and cognitive dysfunction have been observed in inter-episode bipolar disorder (BD) patients. We aimed to create a joint statistical model of white matter integrity and functional response measures in explaining differences in working memory and processing speed among BD patients. Medicated inter-episode BD (n=26; age=45.2±10.1 years) and healthy comparison (HC; n=36; age=46.3±11.5 years) participants completed 51-direction DTI and fMRI while performing a working memory task. Participants also completed a processing speed test. Tract-based spatial statistics identified common white matter tracts where fractional anisotropy was calculated from atlas-defined regions of interest. Brain responses within regions of interest activation clusters were also calculated. Least angle regression was used to fuse fMRI and DTI data to select the best joint neuroimaging predictors of cognitive performance for each group. While there was overlap between groups in which regions were most related to cognitive performance, some relationships differed between groups. For working memory accuracy, BD-specific predictors included bilateral dorsolateral prefrontal cortex from fMRI, splenium of the corpus callosum, left uncinate fasciculus, and bilateral superior longitudinal fasciculi from DTI. For processing speed, the genu and splenium of the corpus callosum and right superior longitudinal fasciculus from DTI were significant predictors of cognitive performance selectively for BD patients. BD patients demonstrated unique brain-cognition relationships compared to HC. These findings are a first step in discovering how interactions of structural and functional brain abnormalities contribute to cognitive impairments in BD. (JINS, 2015, 21, 330–341)

Styles APA, Harvard, Vancouver, ISO, etc.

37

Kadri, Paulo A. S., Jean G. de Oliveira, Niklaus Krayenbühl, Uğur Türe, Evandro P. L. de Oliveira, Ossama Al-Mefty et Guilherme C. Ribas. « Surgical Approaches to the Temporal Horn : An Anatomic Analysis of White Matter Tract Interruption ». Operative Neurosurgery 13, n^o 2 (8 décembre 2016) : 258–70. http://dx.doi.org/10.1093/ons/opw011.

Texte intégral

Résumé :

Abstract BACKGROUND: Surgical access to the temporal horn is necessary to treat tumors and vascular lesions, but is used mainly in patients with mediobasal temporal epilepsy. The surgical approaches to this cavity fall into 3 primary categories: lateral, inferior, and transsylvian. The current neurosurgical literature has underestimated the interruption of involved fiber bundles and the correlated clinical manifestations. OBJECTIVE: To delineate the interruption of fiber bundles during the different approaches to the temporal horn. METHODS: We simulated the lateral (trans-middle temporal gyrus), inferior (transparahippocampal gyrus), and transsylvian approaches in 20 previously frozen, formalin-fixed human brains (40 hemispheres). Fiber dissection was then done along the lateral and inferior aspects under the operating microscope. Each stage of dissection and its respective fiber tract interruption were defined. RESULTS: The lateral (trans-middle temporal gyrus) approach interrupted “U” fibers, the superior longitudinal fasciculus (inferior arm), occipitofrontal fasciculus (ventral segment), uncinate fasciculus (dorsolateral segment), anterior commissure (posterior segment), temporopontine, inferior thalamic peduncle (posterior fibers), posterior thalamic peduncle (anterior portion), and tapetum fibers. The inferior (transparahippocampal gyrus) approach interrupted “U” fibers, the cingulum (inferior arm), and fimbria, and transected the hippocampal formation. The transsylvian approach interrupted “U” fibers (anterobasal region of the extreme capsule), the uncinate fasciculus (ventromedial segment), and anterior commissure (anterior segment), and transected the anterosuperior aspect of the amygdala. CONCLUSION: White matter dissection improves our knowledge of the complex anatomy surrounding the temporal horn. Identifying the fiber bundles at risk during each surgical approach adds important information for choosing the appropriate surgical strategy.

Styles APA, Harvard, Vancouver, ISO, etc.

38

Bassell, Julia, Siddharth Srivastava, Anna K. Prohl, Benoit Scherrer, Kush Kapur, Rajna Filip-Dhima, Elizabeth Berry-Kravis et al. « Diffusion Tensor Imaging Abnormalities in the Uncinate Fasciculus and Inferior Longitudinal Fasciculus in Phelan-McDermid Syndrome ». Pediatric Neurology 106 (mai 2020) : 24–31. http://dx.doi.org/10.1016/j.pediatrneurol.2020.01.006.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

39

Briggs, Robert G., Meherzad Rahimi, Andrew K. Conner, Goksel Sali, Cordell M. Baker, Joshua D. Burks, Chad A. Glenn, James D. Battiste et Michael E. Sughrue. « A Connectomic Atlas of the Human Cerebrum—Chapter 15 : Tractographic Description of the Uncinate Fasciculus ». Operative Neurosurgery 15, suppl_1 (27 septembre 2018) : S450—S455. http://dx.doi.org/10.1093/ons/opy269.

Texte intégral

Résumé :

ABSTRACT In this supplement, we show a comprehensive anatomic atlas of the human cerebrum demonstrating all 180 distinct regions comprising the cerebral cortex. The location, functional connectivity, and structural connectivity of these regions are outlined, and where possible a discussion is included of the functional significance of these areas. In this chapter, we specifically address the regions integrating to form the uncinate fasciculus.

Styles APA, Harvard, Vancouver, ISO, etc.

40

Johnson, Chad P., Jenifer Juranek, Larry A. Kramer, Mary R. Prasad, Paul R. Swank et Linda Ewing-Cobbs. « Predicting Behavioral Deficits in Pediatric Traumatic Brain Injury Through Uncinate Fasciculus Integrity ». Journal of the International Neuropsychological Society 17, n^o 4 (15 avril 2011) : 663–73. http://dx.doi.org/10.1017/s1355617711000464.

Texte intégral

Résumé :

AbstractBehavioral dysregulation is a common and detrimental consequence of traumatic brain injury (TBI) in children that contributes to poor academic achievement and deficits in social development. Unfortunately, behavioral dysregulation is difficult to predict from either injury severity or early neuropsychological evaluation. The uncinate fasciculus (UF) connects orbitofrontal and anterior temporal lobes, which are commonly implicated in emotional and behavioral regulation. Using probabilistic diffusion tensor tractography (DTT), we examined the relationship between the integrity of the UF 3 months post-injury and ratings of executive functions 12 months post-injury in children with moderate to severe TBI and a comparison group with orthopedic injuries. As expected, fractional anisotropy of the UF was lower in the TBI group relative to the orthopedic injury group. DTT metrics from the UF served as a biomarker and predicted ratings of emotional and behavior regulation, but not metacognition. In contrast, the Glasgow Coma Scale score was not related to either UF integrity or to executive function outcomes. Neuroanatomical biomarkers like the uncinate fasciculus may allow for early identification of behavioral problems and allow for investigation into the relationship of frontotemporal networks to brain-behavior relationships. (JINS, 2011, 17, 663–673)

Styles APA, Harvard, Vancouver, ISO, etc.

41

Cattarinussi, Giulia, Hossein Sanjari Moghaddam, Mohammad Hadi Aarabi, Letizia Squarcina, Fabio Sambataro, Paolo Brambilla et Giuseppe Delvecchio. « White Matter Microstructure Associated with the Antidepressant Effects of Deep Brain Stimulation in Treatment-Resistant Depression : A Review of Diffusion Tensor Imaging Studies ». International Journal of Molecular Sciences 23, n^o 23 (6 décembre 2022) : 15379. http://dx.doi.org/10.3390/ijms232315379.

Texte intégral

Résumé :

Treatment-resistant depression (TRD) is a severe disorder characterized by high relapse rates and decreased quality of life. An effective strategy in the management of TRD is deep brain stimulation (DBS), a technique consisting of the implantation of electrodes that receive a stimulation via a pacemaker-like stimulator into specific brain areas, detected through neuroimaging investigations, which include the subgenual cingulate cortex (sgCC), basal ganglia, and forebrain bundles. In this context, to improve our understanding of the mechanism underlying the antidepressant effects of DBS in TRD, we collected the results of diffusion tensor imaging (DTI) studies exploring how WM microstructure is associated with the therapeutic effects of DBS in TRD. A search on PubMed, Web of Science, and Scopus identified 11 investigations assessing WM microstructure in responders and non-responders to DBS. Altered WM microstructure, particularly in the sgCC, medial forebrain bundle, cingulum bundle, forceps minor, and uncinate fasciculus, was associated with the antidepressant effect of DBS in TRD. Overall, the results show that DBS targeting selective brain regions, including the sgCC, forebrain bundle, cingulum bundle, rectus gyrus, anterior limb of the internal capsule, forceps minor, and uncinate fasciculus, seem to be effective for the treatment of TRD.

Styles APA, Harvard, Vancouver, ISO, etc.

42

Seo, Jeong Pyo, Oh Lyong Kim, Seong Ho Kim, Min Cheol Chang, Min-Su Kim, Su Min Son et Sung Ho Jang. « Neural injury of uncinate fasciculus in patients with diffuse axonal injury ». NeuroRehabilitation 30, n^o 4 (1 juin 2012) : 323–28. http://dx.doi.org/10.3233/nre-2012-0762.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

43

Fernandes, Brisa, Alexandre Paim Diaz, Giselli Scaini, Benson Mwangi, Mon-Ju Wu, Joao Quevedo, Marsal Sanches et Jair Soares. « C-Reactive Protein and the Uncinate Fasciculus in Anhedonia and Depression ». Biological Psychiatry 89, n^o 9 (mai 2021) : S272. http://dx.doi.org/10.1016/j.biopsych.2021.02.681.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

44

Bauer, Corinna M., Zaira Cattaneo et Lotfi B. Merabet. « Early blindness is associated with increased volume of the uncinate fasciculus ». European Journal of Neuroscience 47, n^o 5 (16 février 2018) : 427–32. http://dx.doi.org/10.1111/ejn.13848.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

45

Thomas, C., L. Walker, C. Pierpaoli et C. Baker. « The role of the uncinate fasciculus in human visual-associative learning ». Journal of Vision 12, n^o 9 (10 août 2012) : 1189. http://dx.doi.org/10.1167/12.9.1189.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

46

Papagno, Costanza, Alessandra Casarotti, Alessandro Comi, Alberto Pisoni, Federica Lucchelli, Alberto Bizzi, Marco Riva et Lorenzo Bello. « Long-term proper name anomia after removal of the uncinate fasciculus ». Brain Structure and Function 221, n^o 1 (28 octobre 2014) : 687–94. http://dx.doi.org/10.1007/s00429-014-0920-8.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

47

Olson, Ingrid R., Rebecca J. Von Der Heide, Kylie H. Alm et Govinda Vyas. « Development of the uncinate fasciculus : Implications for theory and developmental disorders ». Developmental Cognitive Neuroscience 14 (août 2015) : 50–61. http://dx.doi.org/10.1016/j.dcn.2015.06.003.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

48

Papagno, Costanza. « Naming and the Role of the Uncinate Fasciculus in Language Function ». Current Neurology and Neuroscience Reports 11, n^o 6 (19 août 2011) : 553–59. http://dx.doi.org/10.1007/s11910-011-0219-6.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

49

Rodrigo, S., C. Oppenheim, F. Chassoux, N. Golestani, Y. Cointepas, C. Poupon, F. Semah, J. F. Mangin, D. Le Bihan et J. F. Meder. « Uncinate fasciculus fiber tracking in mesial temporal lobe epilepsy. Initial findings ». European Radiology 17, n^o 7 (12 janvier 2007) : 1663–68. http://dx.doi.org/10.1007/s00330-006-0558-x.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

50

Soliman, Radwa K., Chantal M. W. Tax, Noha Abo-Elfetoh, Ahmed A. Karim, Ayda Youssef, Doaa Kamal et Eman M. Khedr. « Effects of tDCS on Language Recovery in Post-Stroke Aphasia : A Pilot Study Investigating Clinical Parameters and White Matter Change with Diffusion Imaging ». Brain Sciences 11, n^o 10 (26 septembre 2021) : 1277. http://dx.doi.org/10.3390/brainsci11101277.

Texte intégral

Résumé :

Objectives: In this pilot study we investigated the effects of transcranial direct current stimulation (tDCS) on language recovery in the subacute stage of post-stroke aphasia using clinical parameters and diffusion imaging with constrained spherical deconvolution-based tractography. Methods: The study included 21 patients with subacute post-stroke aphasia. Patients were randomly classified into two groups with a ratio of 2:1 to receive real tDCS or sham tDCS as placebo control. Patients received 10 sessions (5/week) bi-hemispheric tDCS treatments over the left affected Broca’s area (anodal electrode) and over the right unaffected Broca’s area (cathodal stimulation). Aphasia score was assessed clinically using the language section of the Hemispheric Stroke Scale (HSS) before and after treatment sessions. Diffusion imaging and tractography were performed for seven patients of the real group, both before and after the 10th session. Dissection of language-related white matter tracts was achieved, and diffusion measures were extracted. A paired Student’s t-test was used to compare the clinical recovery and diffusion measures of the dissected tracts both pre- and post- treatment. The partial correlation between changes in diffusion measures and the language improvements was calculated. Results: At baseline assessment, there were no significant differences between groups in demographic and clinical HSS language score. No significant clinical recovery in HSS was evident in the sham group. However, significant improvements in the different components of HSS were only observed in patients receiving real tDCS. Associated significant increase in the fractional anisotropy of the right uncinate fasciculus and a significant reduction in the mean diffusivity of the right frontal aslant tract were reported. A significant positive correlation was found between the changes in the right uncinate fasciculus and fluency improvement. Conclusions: Aphasia recovery after bi-hemispheric transcranial direct current stimulation was associated with contralesional right-sided white matter changes at the subacute stage. These changes probably reflect neuroplasticity that could contribute to the recovery. Both the right uncinate fasciculus and right frontal aslant tract seem to be involved in aphasia recovery.

Styles APA, Harvard, Vancouver, ISO, etc.

Articles de revues sur le sujet « Uncinate fasciculu »

Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres