Stephane Rousset | Université Grenoble Alpes (original) (raw)

Papers by Stephane Rousset

Cognitive Processing, Aug 2, 2015

The memory alignment effect is the advantage of reasoning from a perspective which is aligned wit... more The memory alignment effect is the advantage of reasoning from a perspective which is aligned with the frame of reference used to encode an environment in memory. It usually occurs when participants have to consciously take a perspective to perform a spatial memory task. The present experiment assesses whether the memory alignment effect can occur without requiring to consciously take a given perspective, when the misaligned perspective is only perceptively provided. In others words, does the memory alignment effect still arise when it is only implicitly prompted? Thirty participants learned a sequence of four objects&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; positions in a room from a north-as-up survey perspective. During the testing phase, they had to point to the direction of a target object from another object (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;the reference&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;) with a fixed north-up orientation. The background behind the reference object displayed either a uniform color (control condition) or a misaligned ground-level perspective. The latter displayed a reference object&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s position information which was either congruent with the studied environment (congruent misaligned condition) or incongruent (incongruent misaligned condition). Mean pointing errors were higher in the congruent misaligned condition than in the control condition, whereas the incongruent misaligned condition did not differ from the control one. The present study shows that the memory alignment effect can arise without requiring a conscious misaligned perspective taking. Moreover, the perceived misaligned perspective must share the same spatial content as the memorized spatial representation in order to induce an alignment effect.

shows a bird’s eye perspective, looking straight down, with 15% of the environment visib... more shows a bird’s eye perspective, looking straight down, with 15% of the environment visible at any moment and the camera scans the map of the environment with a fixed orientation. The camera movement simulates a path of about 20 m with one or two direction changes, and a speed of a moderately paced walk (approximately 1.5 m/sec).</p

presents a straight view from the perspective of a 180 cm tall observer; camera movement... more presents a straight view from the perspective of a 180 cm tall observer; camera movement make it possible to simulate the view of an observer walking through the environment to enhance both spatial immersion and the sense of self agency. The camera movement simulates a path of about 20 m with one or two direction changes, and a speed of a moderately paced walk ( approximately 1.5 m/sec).</p

HAL (Le Centre pour la Communication Scientifique Directe), Jun 7, 2012

HAL (Le Centre pour la Communication Scientifique Directe), 2007

International audienceAre humans able to learn never seen items from pattern attractors generated... more International audienceAre humans able to learn never seen items from pattern attractors generated by a highly distributed artificial neural network? Such attractors are at the core of the memory self refreshing mechanism of human memory models that suppose memories are dynamically maintained in a distributed network (Ans, 2004; Ans & Rousset, 1997, 2000; Ans, Rousset, French & Musca, 2002, 2004). First, an opposition method was implemented to ensure that the attractors are not the items used to train the network, the source items: attractors were selected to resemble (both at the exemplar and the centroïd level) more some control items than the source items. In spite of this very severe selection, new networks trained only on selected attractors performed better at test on the never seen source items than on the never seen control items. The results of two behavioural experiments using the opposition method show that humans, just as networks, exhibit more familiarity with the never seen source items than with the never seen control items. Thus, humans are sensitive to the particular type of information that allows distributed artificial neural networks to dynamically maintain their memory, and this information does not amount to the exemplars used to train the network that produced the attractors

HAL (Le Centre pour la Communication Scientifique Directe), 2015

2020 19th IEEE International Conference on Machine Learning and Applications (ICMLA)

Proofs Proposition 1. A perfect lossy autoencoder of a random variable X with density p is a diff... more Proofs Proposition 1. A perfect lossy autoencoder of a random variable X with density p is a diffeomorphism r of R n minimizing the following expected loss: L λ (r) = E X∼p ||x − r(x)|| 2 2 + λ log |J r| (1) for some λ > 0, where J r being the Jacobian matrix (J r) ij = ∂ri ∂xj .

Proceedings of the 13th International Conference on Agents and Artificial Intelligence, 2021

Consciousness and Cognition, 2015

Recent models suggest that spatial updating of position with self-motion is a key component of re... more Recent models suggest that spatial updating of position with self-motion is a key component of remembering. In the first experiment, participants simultaneously performed a spatial task and a source recall. In the spatial task, blindfolded participants rotated to a new orientation and then pointed to an object&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s position. They pointed either from their new orientation (in the updating condition), or as if they were still in their starting orientation (in the ignoring condition). In the updating condition, participants had to accurately integrate their own movement whereas, in the ignoring condition, they had to ignore it. If spatial updating and episodic memory rely on the same network, only the updating condition should interfere with source recall. Results are in line with this prediction. A second experiment using a semantic memory task instead of source recall showed no interference effect. These results suggest that episodic memory and spatial updating are functionally linked.

Psychological Research

In the field of memory, it is now admitted that an experience of memory is not only the consequen... more In the field of memory, it is now admitted that an experience of memory is not only the consequence of the activation of a precise content, but also results from an inference associated with the transfer of the manner in which the process was carried out (i.e., fluency) in addition to the transfer of the process itself. The aim of this work was to show that experience of memory is also associated with the fluency that is due to the transfer of a processing carried out in our interactions with our past environment. Firstly, participants performed a perceptual discrimination task (geometric shapes: circle or square) that involves a fluent or a non-fluent gesture to respond. Motor fluency vs. non-fluency was implicitly associated with the colour of the geometric shapes. Secondly, participants had to perform a classical memory recognition task. During the recognition phase, items appeared either with the colour associated with motor fluency or with the colour associated with motor non-fluency. We used a Go-NoGo task to avoid having a confused factor (response space). Results show that items were better recognised with a colour associated with motor fluency than with a colour associated with non-motor fluency. These findings support the idea that an experience of memory is also associated with the transfer of the motor feeling of fluency linked to our interaction with the environment.

SIGLECNRS 17660 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

PLOS ONE, 2021

A large body of research has shown that visually induced self-motion (vection) and cognitive proc... more A large body of research has shown that visually induced self-motion (vection) and cognitive processing may interfere with each other. The aim of this study was to assess the interactive effects of a visual motion inducing vection (uniform motion in roll) versus a visual motion without vection (non-uniform motion) and long-term memory processing using the characteristics of standing posture (quiet stance). As the level of interference may be related to the nature of the cognitive tasks used, we examined the effect of visual motion on a memory task which requires a spatial process (episodic recollection) versus a memory task which does not require this process (semantic comparisons). Results confirm data of the literature showing that compensatory postural response in the same direction as background motion. Repeatedly watching visual uniform motion or increasing the cognitive load with a memory task did not decrease postural deviations. Finally, participants were differentially cont...

Motor Control, 2021

The aim of this experiment was to investigate the postural response to specific types of long-ter... more The aim of this experiment was to investigate the postural response to specific types of long-term memory (episodic vs. semantic) in young adults performing an unperturbed upright stance. Although a similar level of steadiness (mean distance) was observed, dual tasking induced a higher velocity, more energy in the higher frequency range (power spectral density), and less regularity (sample entropy) compared with a simple postural task. Moreover, mean velocity was always greater in the semantic than in the episodic task. The differences in postural control during dual tasking may result from the types of processes involved in the memory task. Findings suggest a spatial process sharing between posture and episodic memory.

Review of Philosophy and Psychology, 2014

Although episodic memory is a widely studied form of memory both in philosophy and psychology, it... more Although episodic memory is a widely studied form of memory both in philosophy and psychology, it still raises many burning questions regarding its definition and even its acceptance. Over the last two decades, cross-disciplinary discussions between these two fields have increased as they tackle shared concerns, such as the phenomenology of recollection, and therefore allow for fruitful interaction. This editorial introduction aims to provide a comprehensive and up-to-date presentation of the main existing conceptions and issues on the topic. After delineating Tulving's chief theoretical import and multifaceted legacy, it goes on to chart the different attempts to capture the episodicity feature of memory according to three categories: a first approach aims to show the cognitive abilities required for a subject to episodically remember; the second defines episodicity as a stage-specific feature; the last explains episodicity in terms of the epistemological properties of episodic memory. This state of the art thereby sets the stage for the contributions of the present volume, which will be introduced in conclusion.

Le modele de Tulving (1976, 1982, 1983) prolonge par les modeles d'appariement global (SAM, R... more Le modele de Tulving (1976, 1982, 1983) prolonge par les modeles d'appariement global (SAM, Raaijmakers & Shiffrin, 1981; MINERVA 2, Hintzman, 1988; CHARM, Eich, 1982), considere que le souvenir emerge de la synergie entre les composants des indices presents dans la situation de recuperation et les composants des traces des experiences passees. Le modele SCAPE (Selective Construction And Preservation of Experience) de Whittlesea (Leboe & Whittlesea, 2002; Whittlesea, 1997, 2002) prolonge cette conception de la memoire en proposant que la recuperation d'une connaissance implique deux etapes: a) la construction d'un etat mental qui est de produit de l'appariement entre les composants des indices presents et les composants des experiences passees, b) l'occurrence d'un sentiment subjectif de familiarite, produit d'une evaluation et d'une inference. Ici, l'evaluation ne refere pas a un jugement sur le stimulus, mais a un jugement sur l'acces a l'etat mental construit (i.e. acces facile vs difficile). L'inference repose quant a elle sur le sentiment qui resulte de l'acces a l'etat mental construit. C'est-a-dire que la personne tente d'attribuer a une source objective (i.e., le stimulus) le sentiment subjectif lie a l'acces a l'etat mental (Whittlesea & Williams, 1998). Comme la personne n'est pas consciente que l'etat mental est une construction elle a recours a un processus d'attribution elementaire: si j'ai le sentiment que l'acces a cet etat mental est facile, cela signifie que j'ai deja ete en contact avec le stimulus. En effet la personne a deja fait l'experience que quelque chose de connu est plus facile a traiter que quelque chose d'inconnu. Autrement dit la personne commet une erreur d'attribution qui l'a conduit a produire un jugement de reconnaissance (Whittlesea, 2011)

Advances in Psychology, 1990

AbStI &amp;amp;amp;amp;#x27;8Ct. Context effects in face recognition have been interprete... more AbStI &amp;amp;amp;amp;#x27;8Ct. Context effects in face recognition have been interpreted either in terms of response bias, or as evidence in favour of the specificity encoding principle. This second interpretation was studied through a connectionist simulation. From a cognitive model of ...

Psychological Research, 2014

The aim of this study was to show that sensorymotor consequences of past actions form part of mem... more The aim of this study was to show that sensorymotor consequences of past actions form part of memory trace components cued by current experience. In a first task participants had to learn a list of words. Then in a guessing task they played against the computer. Finally, in a recognition task, they had to judge if the words were or were not present in the learning task. Words appeared either in the colour associated with success or failure in the guessing task, or in a non-informative colour. In the first experiment, results show that when the words to be judged were in the colour associated with success, participants answered faster and produced more ''old'' responses than when the words to be judged were in the colour associated with failure in the previous task. Moreover, when the words to be judged were in the colour associated with failure, participants were slower and produced less ''old'' responses than when the words were in a colour not informative of success or failure. The second experiment confirms that the results obtained in Experiment 1 were linked to the sensory-motor consequences of past actions associated with the colour and not to the colour itself.