1,773 research outputs found
Social cognition in normal and pathological aging
The concept of social cognition refers to a set of skills and to emotional and social experiences regulating relationships between individuals. This concept is appropriate in order to help us to explain individual human behaviours and behaviours in groups. Social cognition involves social knowledge, perception and processing of social cues, and the representation of mental states. The concept of social cognition thus refers to a multitude of skills. This paper stops on several of them, namely theory of mind, empathy, moral reasoning, emotional processing and emotional regulation. We propose a conceptual approach to each of these skills also stopping on their cerebral underpinnings. We also make an inventory of knowledge about the effects of age and neurodegenerative diseases on social cognition
Theory of mind, empathy and emotion perception in cortical and subcortical neurodegenerative diseases
Although the impact of neurodegenerative diseases on everyday interactions is well known in the literature, their impact on social cognitive processes remains unclear. The concept of social cognition refers to a set of skills, all of which are essential for living in a community. It involves social knowledge, perception and processing of social cues, and representation of mental states. This report is a review of recent findings on the impact of cortical and subcortical neurodegenerative diseases on three social cognitive processes, namely, the theory of mind, empathy and processing emotions. The focus here is on a conceptual approach to each of these skills and their cerebral underpinnings
Blind fluorescence structured illumination microscopy: A new reconstruction strategy
In this communication, a fast reconstruction algorithm is proposed for
fluorescence \textit{blind} structured illumination microscopy (SIM) under the
sample positivity constraint. This new algorithm is by far simpler and faster
than existing solutions, paving the way to 3D and/or real-time 2D
reconstruction.Comment: submitted to IEEE ICIP 201
Virtual reality as a new approach to assess cognitive decline in the elderly
Brain aging is a natural process that leads to a change in cognitive functions. Mild Cognitive Impairment (MCI) is a condition in which a person has cognitive functions that are below normal for his age. However, these deficits are not pronounced enough to confirm for the diagnosis of dementia. It is therefore important to develop new ways to assess cognitive functions in the elderly. This would indeed lead to a better identification of the cognitive losses that are related to normal or pathological aging. The objective of this study was to investigate the relevance of virtual reality as a new evaluation approach in psychology. To do this, 10 elderly people with Mild Cognitive Impairment, and 20 elderly people without cognitive problems, were compared using tests of prospective memory that were presented in a traditional way and in virtual reality. The diagnosis of MCI was made using the Montreal Cognitive Assessment (MoCA). Significant differences between the two groups were noted in virtual reality. Nevertheless, no difference was observed between the two groups with the traditional task. A significant positive correlation between the virtual reality task and the MoCA, but not between the traditional task and the MoCA, was observed. An evaluative approach based on virtual reality seems more sensitive to cognitive impairment associated with aging than an approach based on traditional neuropsychological tests.
Utilisation de la Réalité Virtuelle en neuropsychologie clinique
Dans cet article, les principales applications des techniques de Réalité Virtuelle en clinique neuropsychologique sont examinées. Il s\u27agit, d\u27une part, de l\u27aide à l\u27évaluation des troubles cognitifs et comportementaux secondaires aux lésions du système nerveux central et, d\u27autre part, des perspectives ouvertes dans le champ de la prise en charge rééducative de ces déficits. Ces données cliniques et expérimentales permettent de discuter l\u27intérêt et les limites de l\u27utilisation de ces techniques
Early SPI/INTEGRAL contraints on the morphology of the 511 keV line emission in the 4th galactic quadrant
We provide first constraints on the morphology of the 511 keV line emission
from the galactic centre region on basis of data taken with the spectrometer
SPI on the INTEGRAL gamma-ray observatory. The data suggest an azimuthally
symmetric galactic bulge component with FWHM of ~9 deg with a 2 sigma
uncertainty range covering 6-18 deg. The 511 keV line flux in the bulge
component amounts to (9.9+4.7-2.1) 10e-4 ph cm-2 s-1. No evidence for a
galactic disk component has been found so far; upper 2 sigma flux limits in the
range (1.4-3.4) 10e-3 ph cm-2 s-1 have been obtained that depend on the assumed
disk morphology. These limits correspond to lower limits on the bulge-to-disk
ratio of 0.3-0.6.Comment: 5 pages, 3 figures, accepted for publication in A&
Les phénomènes de dépendance à l’environnement: réflexions sur l’autonomie humaine à partir de la clinique neurologique
Dans cet article, nous proposons d’analyser la perte d’autonomie caractérisée par les phénomènes de dépendance à l’environnement observés chez certains patients neurologiques présentant des lésions des lobes frontaux. Des propositions théoriques issues de la neuropsychologie cognitive et de la théorie de la médiation sont développées et confrontées. La démarche offre l’occasion, au plan théorique, de questionner la détérioration possible du système de la personne suite à des lésions cérébrales et, au plan méthodologique, d’interroger notre manière d’examiner ces patients en confrontant les modèles théoriques aux observations clinique
Aggregation of frictional particles due to capillary attraction
Capillary attraction between identical millimeter sized spheres floating at a
liquid-air interface and the resulting aggregation is investigated at low
Reynolds number. We show that the measured capillary forces between two spheres
as a function of distance can be described by expressions obtained using the
Nicolson approximation at low Bond numbers for far greater particle sizes than
previously assumed. We find that viscous hydrodynamics interactions between the
spheres needs to be included to describe the dynamics close to contact. We then
consider the aggregates formed when a third sphere is added after the initial
two spheres are already in contact. In this case, we find that linear
superposition of capillary forces describes the observed approach qualitatively
but not quantitatively. Further, we observe an angular dependence of the
structure due to a rapid decrease of capillary force with distance of
separation which has a tendency to align the particles before contact. When the
three particles come in contact, they may preserve their shape or rearrange to
form an equilateral triangle cluster - the lowest energy state - depending on
the competition between attraction between particles and friction. Using these
observations, we demonstrate that a linear particle chain can be built from
frictional particles with capillary attraction.Comment: accepted for Physical Review
Internal Dust Correction Factors for Star Formation Rates Derived for Dusty \HII Regions and Starburst Galaxies
Star formation rates in galaxies are frequently estimated using the Balmer
line fluxes. However, these can be systematically underestimated because dust
competes for the absorption of Lyman continuum photons in the ionized gas. Here
we present theoretical correction factors in a simple analytic form. T These
factors scale as the product of the ionization parameter, , and the
nebular O/H abundance ratio, both of which can now be derived from the
observation of bright nebular line ratios. The correction factors are only
somewhat dependent upon the photoelectron production by grains, but are very
sensitive to the presence of complex PAH-like carbonaceous molecules in the
ionized gas, providing that these can survive in such an environment.Comment: 13 pages, 1 figures, Accepted for publication in ApJ. (Feb 1, 2003
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