Damage to White Matter Pathways in Subacute and Chronic Spatial Neglect: A Group Study and 2 Single-Case Studies with Complete Virtual "In Vivo" Tractography Dissection

The present study used two single case studies to evaluate clinical improvement as a result of cognitive behavior therapy in panic disorder with or without agoraphobia (PDA). A special emphasis was placed on assessing the reduction in catastrophic cognitions, which are considered to be of prime importance in PDA. Multiple measures were employed, during pre and post treatment and at a six month follow-up. Data from self-report questionnaires, physiological measures and cognitive sampling during in vivo exposure were used. Convergent results demonstrated clinical improvement and supported the importance of catastrophic cognitions in the process of change for treatment outcome of PDA.

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A Meta-analysis on the Characteristics and Effects of Meta-Cognitive Strategic Interventions in Korea : Comparison Between Group-Designed Studies and Single Case Studies

Asian Journal of Education ◽

10.15753/aje.2016.09.17.3.21 ◽

2016 ◽

Vol 17 (3) ◽

pp. 21-48 ◽

Cited By ~ 1

Author(s):

Dongil Kim ◽

Soohyun La ◽

Hyeeun Lee

Keyword(s):

Case Studies ◽

Single Case ◽

Meta Analysis

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Comparing Post-communist Authoritarianism in Russia and China

10.1093/oso/9780190846374.003.0008 ◽

2018 ◽

Author(s):

Cheng Chen

Keyword(s):

Comparative Study ◽

East Asia ◽

Eastern Europe ◽

Case Studies ◽

Single Case ◽

Full Range ◽

Geographical Area ◽

Context Sensitive ◽

Elite Politics ◽

Significant Divergence

The studies of post-communist Russia and China have traditionally been dominated by single-case studies and within-region comparisons. This chapter explores why the CAS of post-communist Russia and China is difficult, why it is rare, and how it could yield significant and unique intellectual payoffs. The cross-regional comparative study of anti-corruption campaigns in contemporary Russia and China is used as an example in this chapter to argue that a well-matched and context-sensitive comparison could reveal significant divergence in the elite politics and institutional capacities of these regimes that would otherwise likely be obscured by single-case studies or studies restricted to one single geographical area such as “Eastern Europe” or “East Asia.” By breaking Russia and China out of their respective “regions,” the CAS perspective thus enables us to better capture the full range of existing diversity of post-communist authoritarianism.

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What Has Direct Cortical and Subcortical Electrostimulation Taught Us about Neurolinguistics?

The Oxford Handbook of Neurolinguistics ◽

10.1093/oxfordhb/9780190672027.013.8 ◽

2019 ◽

pp. 185-211

Author(s):

Hugues Duffau

Keyword(s):

White Matter ◽

Large Scale ◽

Functional Neuroimaging ◽

Great Accuracy ◽

Subcortical White Matter ◽

Cerebral Lesions ◽

Physiological Basis ◽

Postoperative Mri ◽

The Brain

Investigating the neural and physiological basis of language is one of the most important challenges in neurosciences. Direct electrical stimulation (DES), usually performed in awake patients during surgery for cerebral lesions, is a reliable tool for detecting both cortical and subcortical (white matter and deep grey nuclei) regions crucial for cognitive functions, especially language. DES transiently interacts locally with a small cortical or axonal site, but also nonlocally, as the focal perturbation will disrupt the entire subnetwork sustaining a given function. Thus, in contrast to functional neuroimaging, DES represents a unique opportunity to identify with great accuracy and reproducibility, in vivo in humans, the structures that are actually indispensable to the function, by inducing a transient virtual lesion based on the inhibition of a subcircuit lasting a few seconds. Currently, this is the sole technique that is able to directly investigate the functional role of white matter tracts in humans. Thus, combining transient disturbances elicited by DES with the anatomical data provided by pre- and postoperative MRI enables to achieve reliable anatomo-functional correlations, supporting a network organization of the brain, and leading to the reappraisal of models of language representation. Finally, combining serial peri-operative functional neuroimaging and online intraoperative DES allows the study of mechanisms underlying neuroplasticity. This chapter critically reviews the basic principles of DES, its advantages and limitations, and what DES can reveal about the neural foundations of language, that is, the large-scale distribution of language areas in the brain, their connectivity, and their ability to reorganize.

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Structural white-matter connections mediating distinct behavioral components of spatial neglect in right brain-damaged patients

Cortex ◽

10.1016/j.cortex.2015.12.008 ◽

2016 ◽

Vol 77 ◽

pp. 54-68 ◽

Cited By ~ 27

Author(s):

Maarten J. Vaessen ◽

Arnaud Saj ◽

Karl-Olof Lovblad ◽

Markus Gschwind ◽

Patrik Vuilleumier

Keyword(s):

White Matter ◽

Spatial Neglect ◽

Right Brain

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Whole-brain 3D MR fingerprinting brain imaging: clinical validation and feasibility to patients with meningioma

Magnetic Resonance Materials in Physics Biology and Medicine ◽

10.1007/s10334-021-00924-1 ◽

2021 ◽

Author(s):

Thomaz R. Mostardeiro ◽

Ananya Panda ◽

Robert J. Witte ◽

Norbert G. Campeau ◽

Kiaran P. McGee ◽

...

Keyword(s):

White Matter ◽

Statistical Significance ◽

Relaxation Times ◽

Brain Structures ◽

Centrum Semiovale ◽

In Vivo Evaluation ◽

Whole Brain ◽

Mean Values ◽

Caudate Head

Abstract Purpose MR fingerprinting (MRF) is a MR technique that allows assessment of tissue relaxation times. The purpose of this study is to evaluate the clinical application of this technique in patients with meningioma. Materials and methods A whole-brain 3D isotropic 1mm3 acquisition under a 3.0T field strength was used to obtain MRF T1 and T2-based relaxometry values in 4:38 s. The accuracy of values was quantified by scanning a quantitative MR relaxometry phantom. In vivo evaluation was performed by applying the sequence to 20 subjects with 25 meningiomas. Regions of interest included the meningioma, caudate head, centrum semiovale, contralateral white matter and thalamus. For both phantom and subjects, mean values of both T1 and T2 estimates were obtained. Statistical significance of differences in mean values between the meningioma and other brain structures was tested using a Friedman’s ANOVA test. Results MR fingerprinting phantom data demonstrated a linear relationship between measured and reference relaxometry estimates for both T1 (r2 = 0.99) and T2 (r2 = 0.97). MRF T1 relaxation times were longer in meningioma (mean ± SD 1429 ± 202 ms) compared to thalamus (mean ± SD 1054 ± 58 ms; p = 0.004), centrum semiovale (mean ± SD 825 ± 42 ms; p < 0.001) and contralateral white matter (mean ± SD 799 ± 40 ms; p < 0.001). MRF T2 relaxation times were longer for meningioma (mean ± SD 69 ± 27 ms) as compared to thalamus (mean ± SD 27 ± 3 ms; p < 0.001), caudate head (mean ± SD 39 ± 5 ms; p < 0.001) and contralateral white matter (mean ± SD 35 ± 4 ms; p < 0.001) Conclusions Phantom measurements indicate that the proposed 3D-MRF sequence relaxometry estimations are valid and reproducible. For in vivo, entire brain coverage was obtained in clinically feasible time and allows quantitative assessment of meningioma in clinical practice.

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Tractography Alterations in the Arcuate and Uncinate Fasciculi in Post-Stroke Aphasia

Brain Sciences ◽

10.3390/brainsci11010053 ◽

2021 ◽

Vol 11 (1) ◽

pp. 53

Author(s):

Sara Kierońska ◽

Milena Świtońska ◽

Grzegorz Meder ◽

Magdalena Piotrowska ◽

Paweł Sokal

Keyword(s):

White Matter ◽

Brain Connectivity ◽

Three Dimensional ◽

Cerebral White Matter ◽

Neural Pathways ◽

Uncinate Fasciculus ◽

Arcuate Fasciculus ◽

Fiber Tractography ◽

Post Stroke

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.

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Creatine Supplementation for Patients with Inflammatory Bowl Diseases: A Scientific Rationale for a Clinical Trial

Nutrients ◽

10.3390/nu13051429 ◽

2021 ◽

Vol 13 (5) ◽

pp. 1429

Author(s):

Theo Wallimann ◽

Caroline H. T. Hall ◽

Sean P. Colgan ◽

Louise E. Glover

Keyword(s):

Ulcerative Colitis ◽

Clinical Trial ◽

Crohn’S Disease ◽

Pilot Study ◽

Crohn's Disease ◽

Single Case ◽

Initial Period ◽

Creatine Supplementation

Based on theoretical considerations, experimental data with cells in vitro, animal studies in vivo, as well as a single case pilot study with one colitis patient, a consolidated hypothesis can be put forward, stating that “oral supplementation with creatine monohydrate (Cr), a pleiotropic cellular energy precursor, is likely to be effective in inducing a favorable response and/or remission in patients with inflammatory bowel diseases (IBD), like ulcerative colitis and/or Crohn’s disease”. A current pilot clinical trial that incorporates the use of oral Cr at a dose of 2 × 7 g per day, over an initial period of 2 months in conjunction with ongoing therapies (NCT02463305) will be informative for the proposed larger, more long-term Cr supplementation study of 2 × 3–5 g of Cr per day for a time of 3–6 months. This strategy should be insightful to the potential for Cr in reducing or alleviating the symptoms of IBD. Supplementation with chemically pure Cr, a natural nutritional supplement, is well tolerated not only by healthy subjects, but also by patients with diverse neuromuscular diseases. If the outcome of such a clinical pilot study with Cr as monotherapy or in conjunction with metformin were positive, oral Cr supplementation could then be used in the future as potentially useful adjuvant therapeutic intervention for patients with IBD, preferably together with standard medication used for treating patients with chronic ulcerative colitis and/or Crohn’s disease.

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The Role of White Matter Disconnection in the Symptoms Relating to the Anarchic Hand Syndrome: A Single Case Study

Brain Sciences ◽

10.3390/brainsci11050632 ◽

2021 ◽

Vol 11 (5) ◽

pp. 632

Author(s):

Valentina Pacella ◽

Giuseppe Kenneth Ricciardi ◽

Silvia Bonadiman ◽

Elisabetta Verzini ◽

Federica Faraoni ◽

...

Keyword(s):

White Matter ◽

Single Case ◽

Brain Lesion ◽

Structural Connectivity ◽

Disconnection Syndrome ◽

Neuroimaging Data ◽

Neuropsychological Investigation ◽

Anterior Posterior

The anarchic hand syndrome refers to an inability to control the movements of one’s own hand, which acts as if it has a will of its own. The symptoms may differ depending on whether the brain lesion is anterior, posterior, callosal or subcortical, but the relative classifications are not conclusive. This study investigates the role of white matter disconnections in a patient whose symptoms are inconsistent with the mapping of the lesion site. A repeated neuropsychological investigation was associated with a review of the literature on the topic to identify the frequency of various different symptoms relating to this syndrome. Furthermore, an analysis of the neuroimaging regarding structural connectivity allowed us to investigate the grey matter lesions and white matter disconnections. The results indicated that some of the patient’s symptoms were associated with structures that, although not directly damaged, were dysfunctional due to a disconnection in their networks. This suggests that the anarchic hand may be considered as a disconnection syndrome involving the integration of multiple antero-posterior, insular and interhemispheric networks. In order to comprehend this rare syndrome better, the clinical and neuroimaging data need to be integrated with the clinical reports available in the literature on this topic.

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