Malika Auvray

The multisensory perception of flavor.

Following on from ecological theories of perception, such as the one proposed by [Gibson, J. J. (1966). The senses considered as perceptual systems. Boston: Houghton Mifflin] this paper reviews the literature on the multisensory interactions underlying the perception of flavor in order to determine the extent to which it is really appropriate to consider flavor perception as a distinct perceptual system. We propose that the multisensory perception of flavor may be indicative of the fact that the taxonomy currently used to define our senses is simply not appropriate. According to the view outlined here, the act of eating allows the different qualities of foodstuffs to be combined into unified percepts; and flavor can be used as a term to describe the combination of tastes, smells, trigeminal, and tactile sensations as well as the visual and auditory cues, that we perceive when tasting food.

The sensory-discriminative and affective-motivational aspects of pain.

What is the difference between pain and standard exteroceptive perceptual processes, such as vision or audition? According to the most common view, pain constitutes the internal perception of bodily damage. Following on from this definition, pain is just like exteroceptive perception, with the only difference being that it is not oriented toward publicly available objects, but rather toward events that are taking place in/to ones own body. Many theorists, however, have stressed that pain should not be seen as a kind of perception, but rather that it should be seen as a kind of affection or motivation to act instead. Though pain undeniably has a discriminatory aspect, what makes it special is its affective-motivational quality of hurting. In this article, we discuss the relation between pain and perception, at both the conceptual and empirical levels. We first review the ways in which the perception of internal damage differs from the perception of external objects. We then turn to the question of how the affective-motivational dimension of pain is different from the affective-motivational aspects that are present for other perceptual processes. We discuss how these differences between pain and exteroceptive perception can account for the fact that the experience of pain is more subjective than other perceptual experiences.

Reading the World through the Skin and Ears: A New Perspective on Sensory Substitution.

Sensory substitution devices aim at replacing or assisting one or several functions of a deficient sensory modality by means of another sensory modality. Despite the numerous studies and research programs devoted to their development and integration, sensory substitution devices have failed to live up to their goal of allowing one to “see with the skin” (White et al., 1970) or to “see with the brain” (Bach-y-Rita et al., 2003). These somewhat peremptory claims, as well as the research conducted so far, are based on an implicit perceptual paradigm. Such perceptual assumption accepts the equivalence between using a sensory substitution device and perceiving through a particular sensory modality. Our aim is to provide an alternative model, which defines sensory substitution as being closer to culturally implemented cognitive extensions of existing perceptual skills such as reading. In this article, we will show why the analogy with reading provides a better explanation of the actual findings, that is, both of the positive results achieved and of the limitations noticed across the field of research on sensory substitution. The parallel with the most recent two-route and interactive models of reading (e.g., Dehaene et al., 2005) generates a radically new way of approaching these results, by stressing the dependence of integration on the existing perceptual-semantic route. In addition, the present perspective enables us to generate innovative research questions and specific predictions which set the stage for future work.

Perceptual crossing: the simplest online paradigm

Researchers in social cognition increasingly realize that many phenomena cannot be understood by investigating offline situations only, focusing on individual mechanisms and an observer perspective. There are processes of dynamic emergence specific to online situations, when two or more persons are engaged in a real-time interaction that are more than just the sum of the individual capacities or behaviors, and these require the study of online social interaction. Auvray et al.s (2009) perceptual crossing paradigm offers possibly the simplest paradigm for studying such online interactions: two persons, a one-dimensional space, one bit of information, and a yes/no answer. This study has provoked a lot of resonance in different areas of research, including experimental psychology, computer/robot modeling, philosophy, psychopathology, and even in the field of design. In this article, we review and critically assess this body of literature. We give an overview of both behavioral experimental research and simulated agent modeling done using the perceptual crossing paradigm. We discuss different contexts in which work on perceptual crossing has been cited. This includes the controversy about the possible constitutive role of perceptual crossing for social cognition. We conclude with an outlook on future research possibilities, in particular those that could elucidate the link between online interaction dynamics and individual social cognition.

The Perception of Space and Form Recognition in a Simulated Environment: The Case of Minimalist Sensory-Substitution Devices

Whenever we explore a simulated environment, the sensorimotor interactions that underlie our perception of space may be modified. We investigated the conditions under which it is possible to acquire the mastery of new sensorimotor laws and thereby to infer new perceptual spaces. A computer interface, based on the principles of minimalist sensory-substitution devices, was designed to enable different possible links between a users actions (manipulation of a mouse and/or keys of a keyboard) and the resulting pattern of sensory stimulation (visual or auditory) to be established. The interface generated an all-or-none stimulus whose activation varied as a function of the participants exploration of a hidden form. In this study we addressed the following questions: What are the conditions necessary for participants to understand their actions as constituting a displacement in a simulated space? What are the conditions required for participants to conceive of sensations as originating from the encounter with an object situated in this space? Finally, what are the conditions required for participants to recognise forms within this space? The results of the two experiments reported here show that, under certain conditions, participants can interpret the new sensorimotor laws as movements in a new perceptual space and can recognise simple geometric forms, and that this occurs no matter whether the sensory stimulation is presented in the visual or auditory modality.

Tactile short-term memory for stimuli presented on the fingertips and across the rest of the body surface.

The aim of this study was to investigate the extent to which tactile information that is unavailable for full conscious report can be accessed using partial-report procedures. In Experiment 1, participants reported the total number of tactile stimuli (up to six) presented simultaneously to their fingertips (numerosity judgment task). In another condition, after being presented with the tactile display, they had to detect whether or not the position indicated by a (visual or tactile) probe had previously contained a tactile stimulus (partial-report task). Participants correctly reported up to three stimuli in the numerosity judgment task, but their performance was far better in the partial-report task: Up to six stimuli were perceived at the shortest target–probe intervals. A similar pattern of results was observed when the participants performed a concurrent articulatory suppression task (Exp. 2). The results of a final experiment revealed that performance in the partial-report task was overall better for stimuli presented on the fingertips than for stimuli presented across the rest of the body surface. These results demonstrate that tactile information that is unavailable for report in a numerosity task can nevertheless sometimes still be accessed when a partial-report procedure is used instead.

Differentiated audio-tactile correspondences in sighted and blind individuals.

The aim of the present study is to investigate whether the crossmodal correspondence robustly documented between auditory pitch and visual elevation has analogues in the audio-tactile domain. Across 4 experiments, the compatibility effects between intuitively congruent pairs of stimuli (i.e., outward tactile movement, going from the inside of the finger toward the fingertip and increasing pitch, or inward tactile movement and decreasing pitch) and incongruent pairs stimuli (i.e., the reverse associations) were measured. Two methods were compared to assess the behavioral effects of such a correspondence: One where participants have to respond to either the auditory or tactile stimulus presented simultaneously, while ignoring the other (speeded classification task), and the other where the auditory and tactile stimuli are presented sequentially and associated to different response buttons (implicit association test). No significant compatibility effect was observed under the speeded classification task. The implicit association test revealed a significant compatibility effect. This effect was similar in the conditions where the finger was placed vertically and horizontally. However, this implicit association between pitch and tactile movements was not observed in blind participants. These results have methodological implications for the explanation and testing of crossmodal correspondences, and the origin of the widely discussed association between pitch and vertical elevation. (PsycINFO Database Record

Improvement of collaborative selection in 3D complex environments

Closely coupled interactions in 3D Collaborative Virtual Environments present a new challenge for the design of Computer-Human Interfaces. Among emerging issues, the collaborative selection of artifact presents several constraints since it requires a good understanding of the workspace of the partner and a good coordination between their actions. However, existing Collaborative Virtual Environments inhibit some mechanisms of communication and interpersonal awareness processes, and this limits the efficiency of such collaborative tasks. To go beyond these constraints, we propose in this article a metaphor for the collaborative selection of 3D artifacts. The proposed approach exploits the haptic channel through a gestural guidance strategy. Once the target is selected by one partner, the second partner is attracted through a suitable force model toward the target. An experimental study was carried out in the context of molecular design, investigating different working strategies. The results show that the proposed metaphor significantly improves the efficiency of the group during the deformation of molecular structures. Moreover, the proposed approach provides a suitable learning support for beginners and enables the more experienced user to implicitly convey and explain some features of the molecular structures.

Short paper: study of synchronous and colocated collaboration for search tasks

Nowadays, Collaborative Virtual Environments offer new working methods allowing for the association of several experts in the same problem-solving process. These new platforms have the potential to improve the processing of complex environments with large dataflow and requiring different skills. This article proposes the investigation of a synchronous and colocated approach for a molecular design task. The aim of this research is to highlight the role and the contribution of Collaborative Virtual Environments for the improvement of complex tasks fulfillment.

Haptic Shape Constancy Across Distance

To explore haptic shape constancy across distance, we measured perceived curvature thresholds of cylindrical shapes, cut out of acetal resin blocks. On each trial, blindfolded observers used their bare finger to scan the surface of two shapes consecutively. One shape was close to the observer and the other positioned further away. This spatial displacement changes the available proprioceptive information about the object shape, and therefore the combined proprio-tactile information may signal different objects at the two distances. The results reveal a perceptual compensation for the change in proprioceptive information. However, two distinct patterns of distance compensation emerged: the data from one group are consistent with predictions from visual object constancy. The other group of observers demonstrate the reverse pattern of response such that objects further away need to have lower curvature to be perceived having equal curvature. We suggest that perceived haptic curvature across distance depends on observers’ differential weighting of the multiple available cues.