Human beings represent spatial information according to egocentric (body-to-object) and allocentric (object-to-object) frames of reference. In everyday life, we constantly switch from one frame of reference to another in order to react effectively to the specific needs of the environment and task demands. However, to the best of our knowledge, no study to date has investigated the cortical activity of switching and non-switching processes between egocentric and allocentric spatial encodings.
View Article and Find Full Text PDFWhen listeners hear a message produced by their interlocutor, they can predict upcoming words thanks to the sentential context and their attention can be focused on the speaker's communication intention. In two electroencephalographical (EEG) studies, we investigated the oscillatory correlates of prediction in spoken-language comprehension and how they are modulated by the listener's attention. Sentential contexts which were strongly predictive of a particular word were ended by a possessive adjective either matching the gender of the predicted word or not.
View Article and Find Full Text PDF. Since January 2021, the LeksellVantage head frame (V-frame) is used for Gamma Knifetreatments in addition to the historical LeksellG-Frame known as the reference. The aim of this study was to compare the spatial accuracy of treatments with these two frames.
View Article and Find Full Text PDFAdvances in timing research advocate for the existence of two timing mechanisms (automatic vs. controlled) that are related to the level of cognitive control intervening for motor behavior regulation. In the present study, we used the functional near-infrared spectroscopy (fNIRS) cutting-edge technique to examine the hypothesis that prefrontal inhibitory control is needed to perform slow motor activities.
View Article and Find Full Text PDFAdipose tissue is a key regulator of whole-body metabolic fitness because of its role in controlling insulin sensitivity. Obesity is associated with hypertrophic adipocytes with impaired glucose absorption, a phenomenon existing in the ultrarare monogenic disorder Alström syndrome consisting of severe insulin resistance. Inactivation of ALMS1 directly inhibits insulin-mediated glucose absorption in the white adipose tissue and induces severe insulin resistance, which leads to type 2 diabetes, accelerated nonalcoholic liver disease, and fibrosis.
View Article and Find Full Text PDFWe investigated the mechanisms underlying the online-processing of phonological constraints using oddball fast-periodic visual stimulation coupled with EEG. We focused on the Sonority Sequencing Principle and examined whether steady-state visual evoked potentials (SSVEPs) are sensitive to the sonority constraint on syllable onsets. Native French speakers were presented with streams of CCVC non-words (C: consonant, V: vowel) at a fixed 6-Hz base rate.
View Article and Find Full Text PDFIn natural listening situations, understanding spoken sentences requires interactions between several multisensory to linguistic levels of information. In two electroencephalographical studies, we examined the neuronal oscillations of linguistic prediction produced by unimodal and bimodal sentence listening to observe how these brain correlates were affected by the sensory streams delivering linguistic information. Sentence contexts which were strongly predictive of a particular word were ended by a possessive adjective matching or not the gender of the predicted word.
View Article and Find Full Text PDFBackground: Radiosurgery is performed with a diversity of instruments relying usually either on a stereotactic frame or a mask for patient head fixation. Comfort and safety efficacy of the 2 systems have never been rigorously evaluated and compared.
Material And Method: Between February 2016 and January 2017, 58 patients presenting with nonsmall cell lung cancer brain metastases have been treated by Gamma Knife radiosurgery (GKS) with random use of a frame or a mask for fixation were included patients older than 18, with <5 brain metastases (at the exclusion of brainstem and optic pathway's locations) and no earlier history of radiotherapy.
Barded-Biedl syndrome (BBS) is a rare genetic disorder with an unmet medical need for retinal degeneration. Small-molecule drugs were previously identified to slow down the apoptosis of photoreceptors in BBS mouse models. Clinical translation was not practical due to the necessity of repetitive invasive intravitreal injections for pediatric populations.
View Article and Find Full Text PDFIn the context of reducing the patient dose coming from CT scanner examinations without penalizing the diagnosis, the assessment of both patient dose and image quality (IQ) with relevant metrics is crucial. The present study represents the first stage in a larger work, aiming to compare and optimize CT protocols using dose and IQ new metrics. We proposed here to evaluate the capacity of the Non-PreWhitening matched filter with an eye (NPWE) model observer to be a robust and accurate estimation of IQ.
View Article and Find Full Text PDFPeople are able to modify the spontaneous pace of their actions to interact with their environment and others. This ability is underpinned by high-level cognitive functions but little is known in regard to the brain areas that underlie such temporal control. A salient practical issue is that current neuroimaging techniques (e.
View Article and Find Full Text PDFDirect electrical stimulation (DES) is used to perform functional brain mapping during awake surgery and in epileptic patients. DES may be coupled with the measurement of Evoked Potentials (EP) to study the conductive and integrative properties of activated neural ensembles and probe the spatiotemporal dynamics of short- and long-range networks. However, its electrophysiological effects remain by far unknown.
View Article and Find Full Text PDFThe trail making test part B (TMT-B) is one of the most widely used task for the assessment of set-shifting ability in patients. However, the set of brain regions impacting TMT-B performance when lesioned is still poorly known. In this case report, we provide a multimodal analysis of a patient operated on while awake for a diffuse low-grade glioma located in the right supramarginal gyrus.
View Article and Find Full Text PDFObesity is a major risk factor for insulin resistance (IR) and its attendant complications. The pathogenic mechanisms linking them remain poorly understood, partly due to a lack of intermediary monogenic human phenotypes. Here, we report on a monogenic form of IR-prone obesity, Alström syndrome (ALMS).
View Article and Find Full Text PDFAlström Syndrome (ALMS) is an ultra-rare multisystem genetic disorder caused by autosomal recessive variants in the ALMS1 gene, which is located on chromosome 2p13. ALMS is a multisystem, progressive disease characterised by visual disturbance, hearing impairment, cardiomyopathy, childhood obesity, extreme insulin resistance, accelerated non-alcoholic fatty liver disease (NAFLD), renal dysfunction, respiratory disease, endocrine and urologic disorders. Clinical symptoms first appear in infancy with great variability in age of onset and severity.
View Article and Find Full Text PDFDirect electrical stimulation (DES) is used to perform functional brain mapping during awake surgery but its electrophysiological effects remain by far unknown. DES may be coupled with the measurement of evoked potentials (EPs) to study the conductive and integrative properties of activated neural ensembles and probe the spatiotemporal dynamics of short- and long-range networks. We recorded ECoG signals on two patients undergoing awake brain surgery and measured EPs on functional sites after cortical stimulations, using combinations of stimulation parameters.
View Article and Find Full Text PDFThe data management, interpretation and comparison of sets of DNA profiles can be complex, time-consuming and error-prone when performed manually. This, combined with the growing numbers of genetic markers in forensic identification systems calls for expert systems that can automatically compare genotyping results within (large) sets of DNA profiles and assist in profile interpretation. To that aim, we developed a user-friendly software program or DNA eXpert System that is denoted DNAxs.
View Article and Find Full Text PDFObjective: The tremor circuitry has commonly been hypothesized to be driven by one or multiple pacemakers within the cerebello-thalamo-cortical pathway, including the cerebellum, contralateral motor thalamus, and primary motor cortex. However, previous studies, using multiple methodologies, have advocated that tremor could be influenced by changes within the right extrastriate cortex, at both the structural and functional level. The purpose of this work was to evaluate the role of the extrastriate cortex in tremor generation and further arrest after left unilateral stereotactic radiosurgery thalamotomy (SRS-T).
View Article and Find Full Text PDFOBJECTIVEEssential tremor (ET) is the most common movement disorder. Drug-resistant ET can benefit from standard stereotactic deep brain stimulation or radiofrequency thalamotomy or, alternatively, minimally invasive techniques, including stereotactic radiosurgery (SRS) and high-intensity focused ultrasound, at the level of the ventral intermediate nucleus (Vim). The aim of the present study was to evaluate potential correlations between pretherapeutic interconnectivity (IC), as depicted on resting-state functional MRI (rs-fMRI), and MR signature volume at 1 year after Vim SRS for tremor, to be able to potentially identify hypo- and hyperresponders based only on pretherapeutic neuroimaging data.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
July 2018
Direct electrical stimulation (DES) at 60 Hz is used clinically to perform real-time functional mapping of the brain and guide tumor resection during wide-awake neurosurgery. The electrophysiological effects of DES remain by far unknown, both locally and remotely. In this study, by lowering the DES frequency to 9 Hz and by using differential recording of electro-corticographic signals to improve the focality, we were able to observe that the amplitude of the initial P0 component of the direct cortical response increased when the inter-electrode distance was increased and the pulse width was decreased.
View Article and Find Full Text PDFObjectives: The use of zirconia as a framework for prosthetic restorations is increasing due to its favorable mechanical properties. Zirconia also has remarkable aesthetic properties when used as a framework and covered with a layer of cosmetic ceramic. The aim of this study was to compare the fracture toughness of three types of aesthetic ceramics, namely VITA VM®9, ceraMotion® Zr, and IPS e.
View Article and Find Full Text PDFKidney Blood Press Res
August 2018
Bardet Biedl syndrome (BBS) is a rare inherited syndromic condition characterized by renal and extra-renal disorders. Renal defect, at either structural or functional level, is one of the cardinal clinical features, and is a major cause of morbidity. However, the pathogenic mechanism underlying its dysfunction remains largely unknown, and to date only symptomatic treatment with no specific therapy is available for these patients.
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