50 research outputs found
Analyse de références architecturales en Flandres: Référence
No full textCette publication comporte une introduction au séminaire de « Critique architecturale contemporaine » tenu par 3 enseignants avec 3 volets méthodologiques distincts. Il est suivi par les articles rédigés par 2 étudiants, Antoine Ghestem et Constance Leduc, lors des visites en Flandre pour leurs études de cas, intégrant ces 3 outils
REVERIES N °2 / JACQUES GHESTEM : Violon, et RAOUL GOLA : PIANO
No full textComprend : DANSE HONGROISE N °5 / BRAHMS - MELODIE EN FA / ANTOINE RUBINSTEIN - CHANSON HINDOUE / RIMSKY-KORSAKOFF - MENUET / MOZART - AVE MARIA / GOUNOD - SERENADE / F. SCHUBERT - CHANSON DE SOLVEJG / GRIEG - NOCTURNE N °2 EN MI BEMOL / CHOPIN - MENUET DU BOURGEOIS GENTILHOMME / LULLI - VALSE EN LA / BRAHMSBnF-Partenariats, Collection sonore - BelieveContient une table des matière
Endogenous multidien rhythm of epilepsy in rats.
No full textRecent trials of chronic EEG in humans showed that epilepsy is a cyclical disorder of the brain with rhythms at multiple time-scales: circadian, multi-day (multidien) or even seasonal. Here, we analyzed chronic EEG data (>30 days) in male epileptic rats and unraveled not only circadian but also, slower, multidien rhythms of interictal epileptiform activity with periodicity of about 2-3 and 5-7 days. Importantly, seizures were not uniformly distributed over time, but rather clustered at preferential phases of these underlying rhythms, delineating critical circadian times and multidien phase of heightened seizure risk. Multidien rhythms were not synchronous across animals or with human intervention suggesting an endogenous generator. In epilepsy, across species, unknown factors modulate seizure timing in cyclical patterns over multiple days
Mapping global brain reconfigurations following local targeted manipulations
No full textInternational audienceUnderstanding how localized brain interventions influence whole-brain dynamics is essential for deciphering neural function and designing therapeutic strategies. Using longitudinal functional MRI datasets collected from mice, we investigated the effects of focal interventions, such as thalamic lesions and chemogenetic silencing of cortical hubs. We found that these local manipulations disrupted the brain’s ability to sustain network-wide activity, leading to global functional connectivity (FC) reconfigurations. Personalized mouse brain simulations based on experimental data revealed that alterations in local excitability modulate firing rates and frequency content across distributed brain regions, driving these FC changes. Notably, the topography of the affected brain regions depended on the intervention site, serving as distinctive signatures of localized perturbations. These findings suggest that focal interventions produce consistent yet region-specific patterns of global FC reorganization, providing an explanation for the seemingly paradoxical observations of hypo- and hyperconnectivity reported in the literature. This framework offers mechanistic insights into the systemic effects of localized neural modulation and holds potential for refining clinical diagnostics in focal brain disorders and advancing personalized neuromodulation strategies
Caffeine Consumption During Pregnancy Accelerates the Development of Cognitive Deficits in Offspring in a Model of Tauopathy
No full textInternational audiencePsychoactive drugs used during pregnancy can affect the development of the brain of offspring, directly triggering neurological disorders or increasing the risk for their occurrence. Caffeine is the most widely consumed psychoactive drug, including during pregnancy. In Wild type mice, early life exposure to caffeine renders offspring more susceptible to seizures. Here, we tested the long-term consequences of early life exposure to caffeine in THY-Tau22 transgenic mice, a model of Alzheimer's disease-like Tau pathology. Caffeine exposed mutant offspring developed cognitive earlier than water treated mutants. Electrophysiological recordings of hippocampal CA1 pyramidal cells in vitro revealed that early life exposure to caffeine changed the way the glutamatergic and GABAergic drives were modified by the Tau pathology. We conclude that early-life exposure to caffeine affects the Tau phenotype and we suggest that caffeine exposure during pregnancy may constitute a risk-factor for early onset of Alzheimer's disease-like pathology
Progressive decrease of amyloid precursor protein carboxy terminal fragments (APP‐CTFs), associated with tau pathology stages, in Alzheimer's disease
No full textIn Vivo Characterization of Neurophysiological Diversity in the Lateral Supramammillary Nucleus during Hippocampal Sharp-wave Ripples of Adult Rats
No full textInternational audienceThe extent of the networks that control the genesis and modulation of hippocampal sharp-wave ripples (SPW-Rs), which are involved in memory consolidation, remains incompletely understood. Here, we performed a detailed in vivo analysis of single cell firing in the lateral supramammillary nucleus (lSuM) during theta and slow oscillations, including SPW-Rs, in anesthetized rats. We classified neurons as SPW-R-active and SPW-R unchanged according to whether or not they increased their firing during SPW-Rs. We show that lSuM SPW-R active neurons increase their firing prior to SPW-Rs peak power and prior to hippocampal excitatory cell activation. Moreover, lSuM SPW-R-active neurons show increased firing activity during theta and slow oscillations as compared to unchanged neurons. These results suggest that a sub-population of lSuM neurons can interact with the hippocampus during SPW-Rs, raising the possibility that the lSuM may modulate memory consolidation
Cell Assemblies in the Cortico-Hippocampal-Reuniens Network during Slow Oscillations
No full textInternational audienceThe nucleus reuniens (NR) is an important anatomic and functional relay between the medial prefrontal cortex (mPFC) and the hippocampus (HPC). Whether the NR controls neuronal assemblies, a hallmark of information exchange between the HPC and mPFC for memory transfer/consolidation, is not known. Using simultaneous local field potential and unit recordings in NR, HPC, and mPFC in male rats during slow oscillations under anesthesia, we identified a reliable sequential activation of NR neurons at the beginning of UP states, which preceded mPFC ones. NR sequences were spatially organized, from dorsal to ventral NR. Chemical inactivation of the NR disrupted mPFC sequences at the onset of UP states as well as HPC sequences present during sharp-wave ripples. We conclude that the NR contributes to the coordination and stabilization of mPFC and HPC neuronal sequences during slow oscillations, possibly via the early activation of its own sequences
Spatio-temporal heterogeneity in hippocampal metabolism in control and epilepsy conditions
No full textInternational audienceThe hippocampus’s dorsal and ventral parts are involved in different operative circuits, the functions of which vary in time during the night and day cycle. These functions are altered in epilepsy. Since energy production is tailored to function, we hypothesized that energy production would be space- and time-dependent in the hippocampus and that such an organizing principle would be modified in epilepsy. Using metabolic imaging and metabolite sensing ex vivo, we show that the ventral hippocampus favors aerobic glycolysis over oxidative phosphorylation as compared to the dorsal part in the morning in control mice. In the afternoon, aerobic glycolysis is decreased and oxidative phosphorylation increased. In the dorsal hippocampus, the metabolic activity varies less between these two times but is weaker than in the ventral. Thus, the energy metabolism is different along the dorsoventral axis and changes as a function of time in control mice. In an experimental model of epilepsy, we find a large alteration of such spatiotemporal organization. In addition to a general hypometabolic state, the dorsoventral difference disappears in the morning, when seizure probability is low. In the afternoon, when seizure probability is high, the aerobic glycolysis is enhanced in both parts, the increase being stronger in the ventral area. We suggest that energy metabolism is tailored to the functions performed by brain networks, which vary over time. In pathological conditions, the alterations of these general rules may contribute to network dysfunctions
