Search results for " COGNITION"
showing 10 items of 1218 documents
Watching happy faces potentiates incentive salience but not hedonic reactions to palatable food cues in overweight/obese adults
2019
International audience; ‘Wanting’ and ‘liking’ are mediated by distinct brain reward systems but their dissociation in human appetite and overeating remains debated. Further, the influence of socioemotional cues on food reward is little explored. We examined these issues in overweight/obese (OW/OB) and normal-weight (NW) participants who watched food images varying in palatability in the same time as videoclips of avatars looking at the food images while displaying facial expressions (happy, disgust or neutral) with their gaze directed only toward the food or consecutively toward the food and participants. We measured heart rate (HR) deceleration as an index of attentional/incentive salienc…
An Acute Dose of Specific Grape and Apple Polyphenols Improves Endurance Performance: A Randomized, Crossover, Double-Blind versus Placebo Controlled…
2017
International audience; Polyphenols are thought to be an interesting ergogenic aid for exercise and recovery. However, most studies regarding the effects of polyphenols investigated several days of supplementations. The present work aimed to study the effects of an acute intake of grape and apple polyphenols on the capacity to maintain intense exercise, here named endurance performance. Forty-eight physically active men (31 ± 6 years) were included in this study. During the two testing sessions, volunteers completed an endurance test at a high percentage of their maximal aerobic power and time to exhaustion was measured. Respiratory and pain parameters were also monitored. The preceding eve…
Cholesterol Hydroxylating Cytochrome P450 46A1: From Mechanisms of Action to Clinical Applications
2021
Cholesterol, an essential component of the brain, and its local metabolism are involved in many neurodegenerative diseases. The blood-brain barrier is impermeable to cholesterol; hence, cholesterol homeostasis in the central nervous system represents a balance betweenin situbiosynthesis and elimination. Cytochrome P450 46A1 (CYP46A1), a central nervous system-specific enzyme, converts cholesterol to 24-hydroxycholesterol, which can freely cross the blood-brain barrier and be degraded in the liver. By the dual action of initiating cholesterol efflux and activating the cholesterol synthesis pathway, CYP46A1 is the key enzyme that ensures brain cholesterol turnover. In humans and mouse models,…
The Early Indicators of Functional Decrease in Mild Cognitive Impairment
2016
OBJECTIVES: Motor deficiency is associated with cognitive frailty in patients with Mild Cognitive Impairments (MCI). In this study we aimed to test the integrity of the muscle synergy involved in an arm-pointing movement in MCI patients, non-impaired functionally. Thus, we were able to test the hypothesis that early motor indicators exist in this population at a preclinical level. METHODS: The electromyographic signals were collected for 11 muscles in 3 groups: Young Adults (YA), Aged Adults (AA), and MCI patients. The AA and MCI groups presented the same functional status. Each subject performed twenty arm-pointing movements from a standing position. RESULTS: The main differences were (1) …
Direct Sensing of Nutrients via a LAT1-like Transporter in Drosophila Insulin-Producing Cells
2016
Summary Dietary leucine has been suspected to play an important role in insulin release, a hormone that controls satiety and metabolism. The mechanism by which insulin-producing cells (IPCs) sense leucine and regulate insulin secretion is still poorly understood. In Drosophila, insulin-like peptides (DILP2 and DILP5) are produced by brain IPCs and are released in the hemolymph after leucine ingestion. Using Ca2+-imaging and ex vivo cultured larval brains, we demonstrate that IPCs can directly sense extracellular leucine levels via minidiscs (MND), a leucine transporter. MND knockdown in IPCs abolished leucine-dependent changes, including loss of DILP2 and DILP5 in IPC bodies, consistent wit…
Reliable determination of new lipid peroxidation compounds as potential early Alzheimer Disease biomarkers.
2018
Lipid peroxidation plays an important role in Alzheimer Disease, so corresponding metabolites found in urine samples could be potential biomarkers. The aim of this work is to develop a reliable ultra-performance liquid chromatography-tandem mass spectrometry analytical method to determine a new set of lipid peroxidation compounds in urine samples. Excellent sensitivity was achieved with limits of detection between 0.08 and 17 nmol L-1, which renders this method suitable to monitor analytes concentrations in real samples. The method's precision was satisfactory with coefficients of variation around 5-17% (infra-day) and 8-19% (inter-day). The accuracy of the method was assessed by analysis o…
Evolution of Pallial Areas and Networks Involved in Sociality: Comparison Between Mammals and Sauropsids
2019
Birds are extremely interesting animals for studying the neurobiological basis of cognition and its evolution. They include species that are highly social and show high cognitive capabilities. Moreover, birds rely more on visual and auditory cues than on olfaction for social behavior and cognition, just like primates. In primates, there are two major brain networks associated to sociality: (1) one related to perception and decision-making, involving the pallial amygdala (with the basolateral complex as a major component), the temporal and temporoparietal neocortex, and the orbitofrontal cortex; (2) another one related to affiliation, including the medial extended amygdala, the ventromedial …
L’adaptation optimale du mouvement humain au milieu gravitaire
2017
International audience
The Active Inference Approach to Ecological Perception: General Information Dynamics for Natural and Artificial Embodied Cognition
2018
The emerging neurocomputational vision of humans as embodied, ecologically embedded, social agents – who shape and are shaped by their environment – offers a golden opportunity to revisit and revise ideas about the physical and information-theoretic underpinnings of life, mind, and consciousness itself. In particular, the active inference framework (AIF) makes it possible to bridge connections from computational neuroscience and robotics/AI to ecological psychology and phenomenology, revealing common underpinnings and overcoming key limitations. AIF opposes the mechanistic to the reductive, while staying fully grounded in a naturalistic and information theoretic foundation, using the princi…
Brain-like large scale cognitive networks and dynamics
2018
A new approach to the study of the brain and its functions known as Human Connectomics has been recently established. Starting from magnetic resonance images (MRI) of brain scans, it is possible to identify the fibers that link brain areas and to build an adjacency matrix that connects these areas, thus creating the brain connectome. The topology of these networks provides a lot of information about the organizational structure of the brain (both structural and functional). Nevertheless this knowledge is rarely used to investigate the possible emerging brain dynamics linked to cognitive functions. In this work, we implement finite state models on neural networks to display the outcoming bra…