Altered network efficiency in isolated REM sleep behavior disorder: A multicentric study

INTRODUCTION: Isolated rapid eye movement (REM) sleep behavior disorder (iRBD), characterized by abnormal movements during REM sleep, is a prodromal stage of dementia with Lewy bodies (DLB) and Parkinson's disease (PD). While iRBD shows emerging brain changes, their impact on structural connectivity and network efficiency, and their predictive value, remain poorly characterized. METHODS: In this international prospective study, 198 polysomnography‐confirmed iRBD patients and 174 controls underwent diffusion magnetic resonance imaging and were analyzed. Cutting‐edge diffusion tractography and network‐based statistics were applied to reconstruct individual connectomes and assess network properties predicting DLB or PD. RESULTS: Structural architecture was already disrupted in iRBD, with both reduced and compensatory increased connections. Global efficiency was decreased. Local efficiency in motor regions was altered and associated with early clinical symptoms. Altered local efficiency in the supramarginal gyrus predicted DLB only. DISCUSSION: Early disruption of brain architecture in iRBD predicts progression to synucleinopathy‐related dementia, offering a novel potential prognostic biomarker. Highlights: Isolated rapid eye movement sleep behavior disorder (iRBD) patients show significant alterations in inter‐regional structural connectivity. Global efficiency is reduced in iRBD compared to controls. Areas with increased local efficiency contribute to decreased global efficiency. Altered network efficiency is associated with emerging Parkinsonian features. Higher supramarginal efficiency predicts dementia with Lewy bodies in iRBD

Development and use of a computerized system to track the competency development of family medicine residents: analysis of the convergence between system proposals and assessor decisions

AbstractIn recent decades, a number of training environments have moved toward program approaches targeting the development of competencies. Because of their complexity, monitoring the development of those competencies is a considerable challenge. Our hypothesis is that a computerized system could help overcome this challenge if it is well accepted by its users. We first summarize the context surrounding the implementation of such approaches. Next, we present a computerized assessment system established in the Family Medicine Residency Program of Laval University (Québec, Canada) that we have developed for tracking the development of residents’ competencies. We then present the analysis of interactions between the system and users and the various proposals that were made to improve the system and longitudinal tracking of the development of the targeted competencies. We consider that this research provides useful guidelines for the computerized monitoring of learners' competencies development and for the design of such systems.</jats:p

Development and use of a computerized system to track the competency development of family medicine residents: analysis of the convergence between system proposals and assessor decisions

In recent decades, a number of training environments have moved toward program approaches targeting the development of competencies. Because of their complexity, monitoring the development of those competencies is a considerable challenge. Our hypothesis is that a computerized system could help overcome this challenge if it is well accepted by its users. We first summarize the context surrounding the implementation of such approaches. Next, we present a computerized assessment system established in the Family Medicine Residency Program of Laval University (Québec, Canada) that we have developed for tracking the development of residents’competencies. We then present the analysis of interactions between the system and users and the various proposals that were made to improve the system and longitudinal tracking of the development of the targeted competencies. We consider that this research provides useful guidelines for the computerized monitoring of learners’ competencies development and for the design of such systems

Data from: Electrically induced verbal perseveration: a striatal deafferentation model

Objective: The present study aimed to elucidate the neural correlates of the deafferentation cognitive model of verbal perseveration (VP) by analyzing the connectomics of the sites where electrical stimulation elicited VP during awake left glioma surgery. Methods: We retrospectively reviewed the anatomical sites that generated VP when electrically stimulated, in a series of 21 patients operated on while awake for a left glioma. Each stimulation point was manually located on the postoperative MRI and then registered to the Montreal Neurological Institute template. Connectomics of these sites were further analyzed using Tractotron and disconnectome maps. Results: VP stimulation sites were located within the white matter surrounding the postero-superior head of the caudate nucleus, as well as within the white matter of the external capsule and the supero-lateral wall of the temporal horn of the ventricle. Furthermore, tractotron and disconnectome maps revealed the connectome of these stimulation sites: the inferior fronto-occipital fasciculus, fronto-striatal tract, and anterior thalamic radiations. Conclusion: Based on these results and other data, we propose the following anatomical implementation of the deafferentation cognitive model: the lexico-semantic system – comprising different areas linked together through direct cortico-cortical connections – sends information to the striatum; the striato-thalamic system acts as a tunable filter of this lexico-semantic input; and the thalamus projects back to the lexico-semantic system, amplifying the targeted response and inhibiting its competitors

Electrically induced verbal perseveration: A striatal deafferentation model

International audienceObjective The present study aimed to elucidate the neural correlates of the deafferentation cognitive model of verbal perseveration (VP) by analyzing the connectomics of the sites where electric stimulation elicited VP during awake left glioma surgery. Methods We retrospectively reviewed the anatomic sites that generated VP when electrically stimulated in a series of 21 patients operated on while awake for a left glioma. Each stimulation point was manually located on the postoperative MRI and then registered to the Montreal Neurological Institute template. Connectomics of these sites were further analyzed with Tractotron and disconnectome maps. Results VP stimulation sites were located within the white matter surrounding the posterosuperior head of the caudate nucleus, as well as within the white matter of the external capsule and the superolateral wall of the temporal horn of the ventricle. Furthermore, Tractotron and disconnectome maps revealed the connectome of these stimulation sites: the inferior fronto-occipital fasciculus, frontostriatal tract, and anterior thalamic radiations. Conclusion On the basis of these results and other data, we propose the following anatomic implementation of the deafferentation cognitive model: the lexico-semantic system, comprising different areas linked together through direct cortico-cortical connections, sends information to the striatum; the striato-thalamic system acts as a tunable filter of this lexico-semantic input; and the thalamus projects back to the lexico-semantic system, amplifying the targeted response and inhibiting its competitors

Validation d'un outil critérié d'évaluation des compétences des résidents en médecine familiale : étude qualitative du processus de réponse

Contexte : L'implantation de l'approche par compétences prescrit aux programmes de formation médicale postdoctorale un ajustement de leurs stratégies d'évaluation. Un outil critérié d'évaluation des compétences (OCÉC) a été élaboré à partir de jalons ayant fait l'objet d'une validation de contenu, mais le processus de réponse restait à valider avant son implantation. Objectifs : Évaluer le processus de réponse à l'OCÉC et identifier les difficultés rencontrées par ses usagers pouvant introduire des biais dans l'évaluation. Méthodes : Étude qualitative auprès de dix cliniciens-enseignants volontaires. La collecte de données s'est effectuée au cours d'entrevues individuelles utilisant la méthode de la pensée à voix haute. Une analyse de contenu des verbatims a été réalisée par trois chercheurs, ce qui a permis la triangulation des données. La structure de codification se compose de quatre thèmes : compréhension, récupération de l'information, jugement et sélection de la réponse. Résultats : La compréhension et la récupération de l'information posaient généralement peu problème. Des difficultés aux étapes du jugement (indicateurs hétérogènes et évaluation normative) et de sélection de la réponse (échelle de réponse inadéquate) ont été relevées. Discussion et conclusion : Cette étude a permis de vérifier le processus de réponse à l'OCÉC, qui s'est avéré adéquat pour la compréhension et la récupération de l'information, mais à améliorer en regard du jugement et de la sélection de la réponse. L'OCÉC a été révisé en fonction des résultats obtenus avant son implantation. L'évaluation en cours de la structure interne, des relations avec d'autres variables et des conséquences du test complétera le processus de validation de l'OCÉC

Dissociating motor–speech from lexico-semantic systems in the left frontal lobe: insight from a series of 17 awake intraoperative mappings in glioma patients

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Développement, validation et implantation d’un outil novateur critérié d’évaluation de la progression des compétences des résidents en médecine familiale

Contexte : Avec l’adoption de son cursus axé sur les compétences, le Collège des médecins de famille du Canada invite les programmes de résidence à fournir aux cliniciens enseignants des outils pour mieux guider l’évaluation formative et sanctionnelle des résidents, tels que des indicateurs de développement observables qui définissent les attentes à des étapes significatives de la formation. But : Développer un outil critérié d’évaluation de la progression du développement des compétences reposant sur les attentes des cliniciens enseignants quant au moment d’acquisition des différentes compétences pour chacun des rôles « CanMEDS-médecine familiale » durant la résidence. Méthodes : Les intervalles attendus pour démontrer diverses compétences ont d’abord été définis par méthodologie Delphi auprès de 33 cliniciens enseignants en médecine familiale de l’Université Laval (Québec, Canada). Les validités de contenu et de convergence ont été vérifiées. Un système informatisé a ensuite été développé pour relier les différents niveaux d’autonomie aux intervalles attendus pour le développement des compétences. Le système identifie, au besoin, les diagnostics pédagogiques possibles et suggère des prescriptions pédagogiques. Résultats : L’outil permet de suivre le développement de 34 compétences réparties sous les sept rôles « CanMEDs-médecine familiale » selon trois niveaux d’autonomie : peu autonome, partiellement autonome et autonome et identifie si la progression de chaque compétence se fait selon les attentes. Conclusions/implications : Cet outil novateur critérié d’évaluation de la progression des compétences des résidents permet non seulement d’apprécier cette progression, mais aussi de guider le développement de leurs compétences. Une étude de validation psychométrique est en cours afin d’évaluer l’impact de l’outil sur la qualité des évaluations, sur la pratique des cliniciens enseignants et sur le parcours des résidents