Search results for "REPRESENTATION"
showing 10 items of 1710 documents
The role of posterior parietal cortices on prismatic adaptation effects on the representation of time intervals
2013
Previous studies provided evidence of an ascending left-to-right spatial representation of time durations by using a technique affecting high levels of spatial cognition, i.e. prismatic adaptation (PA). Indeed, PA that induced a leftward aftereffect distorted time representation toward an underestimation, while PA that induced a rightward aftereffect distorted time representation toward an overestimation. The present study advances previous findings on the effects of PA on time by investigating the neural basis subtending these effects. We focused on the posterior parietal cortex (PPC) since it is involved in the PA procedure and also in the formulation of the spatial representation of time…
Distinctive Representation of Mispredicted and Unpredicted Prediction Errors in Human Electroencephalography
2015
The predictive coding model of perception proposes that neuronal responses are modulated by the amount of sensory input that the internal prediction cannot account for (i.e., prediction error). However, there is little consensus on what constitutes nonpredicted stimuli. Conceptually, whereas mispredicted stimuli may induce both prediction error generated by prediction that is not perceived and prediction error generated by sensory input that is not anticipated, unpredicted stimuli involves no top-down, only bottom-up, propagation of information in the system. Here, we examined the possibility that the processing of mispredicted and unpredicted stimuli are dissociable at the neurophysiologic…
Neurobiological signature of intimacy in anorexia nervosa
2019
Background Intimacy and psychosexual development represent core problems of anorexia nervosa (AN). Experiential and neurobiological evidence however is scarce. Material and methods Thirty-one female AN patients were compared with 35 non-patients (NP) and 22 recovered participants (REC) by using functional magnetic resonance imaging. Participants viewed pictures of couples in intimate relationships and control stimuli. Results AN patients experienced intimate stimuli with lower valence and dominance. AN showed decreased activation of parietal cortices. NP decreased the prefrontal cortex response, which AN patients did not. REC participants did not differ from NP on a behavioural level, thoug…
Quantifying stenosis in renal arteriograms: a fuzzy syntactic analysis.
1999
AbstractThe introduction of fuzzy logic improves a system for the automatic quantification of renal artery lesions seen in digital subtraction angiograms. A two-step approach has been followed. An earlier system based on non-fuzzy syntactic analysis provided a clear symbolic description of the stenotic lesions. Although this system worked correctly, it did not take into account the variability and uncertainty inherent to image processing and to knowledge on the reference diameter. This system has been improved by the introduction of fuzzy logic in the representation of the reference diameter. It provides a description of the stenosis in terms of fuzzy quantities. To illustrate the benefits …
Thompson Sampling Guided Stochastic Searching on the Line for Non-stationary Adversarial Learning
2015
This paper reports the first known solution to the N-Door puzzle when the environment is both non-stationary and deceptive (adversarial learning). The Multi-Armed-Bandit (MAB) problem is the iconic representation of the exploration versus exploitation dilemma. In brief, a gambler repeatedly selects and play, one out of N possible slot machines or arms and either receives a reward or a penalty. The objective of the gambler is then to locate the most rewarding arm to play, while in the process maximize his winnings. In this paper we investigate a challenging variant of the MAB problem, namely the non-stationary N-Door puzzle. Here, instead of directly observing the reward, the gambler is only…
Polar Bear in 'Fortitude'. Affective Aesthetics and Politics of Climate Change
2021
In the first season of the television Eco Noir crime series “Fortitude” (2015) the polar bear appears as a sticky object that embodies an ambiguous affective charge as an icon of global warming. This article discusses the ways in which the polar bear evokes viewer affect in the series through two discourses. The first one relates to violence, essentially present in crime narratives, and how the human and nonhuman animal are positioned in relation to global warming, violence and each other. It raises questions of place and belonging in a local and global context and examines how the polar bear is constructed in terms of stranger danger and victimization in relation to human animals and the t…
Deafferentation and pointing with visual double-step perturbations
1999
The capability of reprogramming movement responses following changes in the visual goal has been studied through the double-step paradigm. These studies have shown that: (a) continuous internal feedback-loops correct unconsciously the dynamic errors throughout the movement; (b) proprioceptive information and/or the efference copy have a privileged status among central processes, insuring on-line regulation of the initial motor commands; and (c) generation of the motor program starts after target presentation, and is continuously updated in the direction of the current internal representation of the target, at least until the onset of hand movement. This main corrective process of the initia…
Nuevas terminaciones para nuevas realidades: performatividad, afiliación y atenuación en la comunidad de habla LGTBI
2021
Este artículo presenta un estudio sobre las terminaciones -i/-is y -e/-es en la comunidad de habla LGTBI. La motivación de esta investigación viene de la representación del género no binario en la lengua española, marcado recientemente por las terminaciones en -e, que además es utilizado para crear un plural inclusivo que evite el masculino genérico. En la misma línea, se han detectado usos, dentro de la comunidad de habla LGTBI, de otro grupo de terminaciones (-i/-is) que parecen anular la distinción de género. Los datos han sido extraídos de una encuesta sociolingüística elaborada por el autor de este trabajo. En la parte sociolingüística se pretende perfilar el tipo de usuario de estas t…
Darstellung von Hyperebenen in verallgemeinerten affinen Räumen durch Moduln
1994
The starting point of this article is a generalized concept of affine space which includes all affine spaces over unitary modules. Our main result is a representation theorem for hyperplanes of affine spaces: Every hyperplane which satisfies a weak richness condition is induced by a module. 1
Affine Kettengeometrien �ber Jordanalgebren
1996
It is shown that an affine chain geometry over a Jordan algebra can be constructed in a nearly classical manner. Conversely, such chain geometries are characterized as systems of rational normal curves having a group of automorphisms with certain properties.