L'homme gothique contre l'homme classique. Huysmans, Worringer et l'héritage grec

International audienceJ.-K. Huysmans est connu pour son rejet du monde méridional et de la culture antique. Il incarne parfaitement "l'homme gothique", contre "l'homme classique", définis par Wilhelm Worringer (1881-1965) dans "L'Art gothique" (1927)

Huysmans et l’affaire de l’Index (1898-1899)

International audienceEn 1898 et 1899, l'oeuvre de Huysmans fait l'objet d'une dénonciation auprès du Saint-Siège, mêlant Secrétairerie d'État, Saint-Office et Congrégation de l'Index. L'oeuvre n'a cependant pas été mise en l'Index. Le présent article s'appuie sur les archives inédites de la Congrégation pour la Doctrine de la foi pour éclairer cette affaire

Gene flow rise with habitat fragmentation in the bog fritillary butterfly (Lepidoptera: Nymphalidae)

<p>Abstract</p> <p>Background</p> <p>The main components of the spatial genetic structure of the populations are neighbourhood size and isolation by distance. These may be inferred from the allele frequencies across a series of populations within a region. Here, the spatial population structure of <it>Proclossiana eunomia </it>was investigated in two mountainous areas of southern Europe (Asturias, Spain and Pyrenees, France) and in two areas of intermediate elevation (Morvan, France and Ardennes, Belgium).</p> <p>Results</p> <p>A total of eight polymorphic loci were scored by allozyme electrophoresis, revealing a higher polymorphism in the populations of southern Europe than in those of central Europe.</p> <p>Isolation by distance effect was much stronger in the two mountain ranges (Pyrenees and Asturias) than in the two areas of lower elevation (Ardennes and Morvan). By contrast, the neighbourhood size estimates were smaller in the Ardennes and in the Morvan than in the two high mountain areas, indicating more common movements between neighbouring patches in the mountains than in plains.</p> <p>Conclusion</p> <p>Short and long dispersal events are two phenomena with distinct consequences in the population genetics of natural populations. The differences in level of population differentiation within each the four regions may be explained by change in dispersal in lowland recently fragmented landscapes: on average, butterflies disperse to a shorter distance but the few ones which disperse long distance do so more efficiently. Habitat fragmentation has evolutionary consequences exceeding by far the selection of dispersal related traits: the balance between local specialisation and gene flow would be perturbed, which would modify the extent to which populations are adapted to heterogeneous environments.</p

Brain responses in humans reveal ideal observer-like sensitivity to complex acoustic patterns

This study was funded by a Deafness Research UK fellowship and Wellcome Trust Project Grant 093292/Z/10/Z (to M.C.)

Neural Correlates of Auditory Figure-Ground Segregation Based on Temporal Coherence

To make sense of natural acoustic environments, listeners must parse complex mixtures of sounds that vary in frequency, space, and time. Emerging work suggests that, in addition to the well-studied spectral cues for segregation, sensitivity to temporal coherence-the coincidence of sound elements in and across time-is also critical for the perceptual organization of acoustic scenes. Here, we examine pre-attentive, stimulus-driven neural processes underlying auditory figure-ground segregation using stimuli that capture the challenges of listening in complex scenes where segregation cannot be achieved based on spectral cues alone. Signals ("stochastic figure-ground": SFG) comprised a sequence of brief broadband chords containing random pure tone components that vary from 1 chord to another. Occasional tone repetitions across chords are perceived as "figures" popping out of a stochastic "ground." Magnetoencephalography (MEG) measurement in naïve, distracted, human subjects revealed robust evoked responses, commencing from about 150 ms after figure onset that reflect the emergence of the "figure" from the randomly varying "ground." Neural sources underlying this bottom-up driven figure-ground segregation were localized to planum temporale, and the intraparietal sulcus, demonstrating that this area, outside the "classic" auditory system, is also involved in the early stages of auditory scene analysis.

Is predictability salient? A study of attentional capture by auditory patterns.

In this series of behavioural and electroencephalography (EEG) experiments, we investigate the extent to which repeating patterns of sounds capture attention. Work in the visual domain has revealed attentional capture by statistically predictable stimuli, consistent with predictive coding accounts which suggest that attention is drawn to sensory regularities. Here, stimuli comprised rapid sequences of tone pips, arranged in regular (REG) or random (RAND) patterns. EEG data demonstrate that the brain rapidly recognizes predictable patterns manifested as a rapid increase in responses to REG relative to RAND sequences. This increase is reminiscent of the increase in gain on neural responses to attended stimuli often seen in the neuroimaging literature, and thus consistent with the hypothesis that predictable sequences draw attention. To study potential attentional capture by auditory regularities, we used REG and RAND sequences in two different behavioural tasks designed to reveal effects of attentional capture by regularity. Overall, the pattern of results suggests that regularity does not capture attention.This article is part of the themed issue 'Auditory and visual scene analysis'

A Brain System for Auditory Working Memory

The brain basis for auditory working memory, the process of actively maintaining sounds in memory over short periods of time, is controversial. Using functional magnetic resonance imaging in human participants, we demonstrate that the maintenance of single tones in memory is associated with activation in auditory cortex. In addition, sustained activation was observed in hippocampus and inferior frontal gyrus. Multivoxel pattern analysis showed that patterns of activity in auditory cortex and left inferior frontal gyrus distinguished the tone that was maintained in memory. Functional connectivity during maintenance was demonstrated between auditory cortex and both the hippocampus and inferior frontal cortex. The data support a system for auditory working memory based on the maintenance of sound-specific representations in auditory cortex by projections from higher-order areas, including the hippocampus and frontal cortex

Diversité génétique, variation géographique et flux géniques chez quelques Lépidoptères Rhopalocères français

International audienceWe present here a comparative and synthetic study of the genetic structure of the populations of three French butterfly species, Proclossiana eunomia, Parnassius apollo and Euphydryas aurinia. Using allozyme electrophoresis, it is possible to estimate the level of genetic variation within and between populations of these species in various regions of France and neighbouring countries. These data also allow us to suggest an explanation of this variation: present functioning of populations and metapopulations, adaptation to foodplants and history of the European biomes during the last twenty millenia. Each of the presented cases presents a biogeographical specificity: very disjunct distribution of the “glacial relict” type (Proclossiana eunomia), widespread mountain species, presently in strong regression (Parnassius apollo), ecologically very diversified species (Euphydryas aurinia). Generally speaking, genetic variation is large at both local and regional scale in southern regions where the genetic structure follows a clear geographic structure. Northern populations show a lower genetic diversity and a confused genetic structure, with an isolation-by-distance effect lower or absent. This phenomenon is the most obvious in P. eunomia populations resulting from a deliberate introduction in northeastern Massif Central 25 years ago. In the case of E. aurinia, the adaptation to different foodplants plays a rôle in genetic differentiation and its geographic variation. These characteristics can be explained at least in part by the postglacial colonization of northern Europe from southern refugia where temperate and mediterranean biomes were concentrated during glacial times. This extension has been accompanied by a loss of genetic diversity and a variation without clearcut geographic organization. Otherwise, the very large ecological diversity of southern Europe has allowed and still allows a larger genetic differentiation within species. The northwards shift of species distribution associated with present climate change is therefore likely to cause a severe loss of genetic diversity within species.Nous présentons une étude synthétique et comparative de la structure génétique des populations de trois papillons diurnes français, Proclossiana eunomia, Parnassius apollo et Euphydryas aurinia. Grâce à l’électrophorèse des allozymes, il a été possible d’estimer comparativement le niveau de variation génétique à l’intérieur des divers peuplements des espèces étudiées. Ces données permettent également de proposer des éléments d’explication de cette variation: fonctionnement actuel des populations et métapopulations, histoire des biomes ouest-européens au cours des vingt derniers millénaires. Chacun des cas étudiés possède une spécificité biogéographique: distribution de type „ relique glaciaire ” très disjointe (P. eunomia), espèce de montagne largement répandue, mais en forte régression (P. apollo), espèce très diversifiée écologiquement (E. aurinia). D’une manière générale, les populations méridionales montrent des variations importantes au niveau local et régional et présentent une structuration géographique nette. Les populations septentrionales montrent une diversité génétique plus faible et une structuration spatiale confuse, avec un effet d’isolement par la distance faible ou absent. Ce phénomène est le plus accusé pour les populations du Nord-Est du Massif Central de P. eunomia, qui résultent d’une introduction délibérée datant de 25 ans. Dans le cas d’ E. aurinia, l’adaptation à des plantes nourricières différentes est aussi liée à la différenciation génétique et à sa variation géographique. Ces caractéristiques peuvent être au moins partiellement expliquées par la colonisation postglaciaire du nord de l’Europe à partir des refuges méridionaux où les biomes tempérés et méditerranéens étaient concentrés pendant les glaciations. Cette colonisation s’est accompagnée d’une perte de diversité génétique et d’une variation sans structuration géographique nette. Par ailleurs, la diversification écologique très élevée du sud de l’Europe permet et a permis une plus grande diversification génétique. Le glissement vers le nord des aires de nombreuses espèces risque donc de s’accompagner d’une perte de diversité génétique

Detecting and representing predictable structure during auditory scene analysis

We use psychophysics and MEG to test how sensitivity to input statistics facilitates auditory-scene-analysis (ASA). Human subjects listened to ‘scenes’ comprised of concurrent tonepip streams (sources). On occasional trials a new source appeared partway. Listeners were more accurate and quicker to detect source appearance in scenes comprised of temporally-regular (REG), rather than random (RAND), sources. MEG in passive listeners and those actively detecting appearance events revealed increased sustained activity in auditory and parietal cortex in REG relative to RAND scenes, emerging ~400 ms of scene-onset. Over and above this, appearance in REG scenes was associated with increased responses relative to RAND scenes. The effect of temporal structure on appearance-evoked responses was delayed when listeners were focused on the scenes relative to when listening passively, consistent with the notion that attention reduces ‘surprise’. Overall, the results implicate a mechanism that tracks predictability of multiple concurrent sources to facilitate active and passive ASA