This article reviews experimental evidence for a specific sensorimotor function which can be dissociated from higher level representations of space. It attempts to delineate this function on the basis of results obtained by psychophysical experiments performed with brain damaged and healthy subjects. Eye and hand movement control exhibit automatic features, such that they are incompatible with conscious control. In addition, they rely on a reference frame different from the one used by conscious perception. Neuropsychological cases provide a strong support for (...) this specific motor representation of space, which can be spared in patients with lesions of primary sensory systems who have lost conscious perception of visual, tactile or proprioceptive stimuli. Observation of these patients also showed that their motor behavior can be ''attracted'' by a goal only under specific conditions, that is, when the response is immediate and when no cognitive representation of this goal is elaborated at the same time. Beyond the issue of the dissociation between an implicit motor representation and more cognitive processing of spatial information, the issue of the interaction between these two systems is thus a matter of interest. It is suggested that the conscious, cognitive representation of a stimulus can contaminate or override the short-lived motor representation, but no reciprocal influence seem to occur. The interaction observed in patients can also be investigated in normals. The literature provides examples of interaction between sensorimotor and cognitive framing of space, which confirm that immediate action is not mediated by the same system as delayed action, and that elaborating a categorial representation of the action goal prevents the expression of the short-lived sensorimotor representation. It is concluded that action can be controlled by a sensory system which is specialized for on-line processing of relevant goal characteristics. The temporal constraints of this system are such that it can affect the action before a full sensory analysis of this goal has been completed. The performance obtained on the basis of this spatial sensory processing suggests that short-lived motor representations may rather be considered as real ''presentation'' of the action world, which share its metric properties. (shrink)

INTRODUCTION Beyond Dissociations Reassembling the mind-brain after all? Yves Rossetti Antti Revonsuo "Comme des banes de poissons de meme espece, ...

Philosophical considerations as well as several recent studies from neurophysiology, neuropsychology, and psychophysics converged in showing that the peripersonal space is structured in a body-centred manner and represented through integrated sensory inputs. Multisensory representations may deserve the function of coding peripersonal space for avoiding or interacting with objects. Neuropsychological evidence is reviewed for dynamic interactions between space representations and action execution, as revealed by the behavioural effects that the use of a tool, as a physical extension of the reachable space, (...) produces on visual–tactile extinction. In particular, tool-use transiently modifies action space representation in a functionally effective way. The possibility is discussed that the investigation of multisensory space representations for action provides an empirical way to consider in its specificity pre-reflexive self-consciousness by considering the intertwining of self-relatedness and object-directness of spatial experience shaped by multisensory and sensorimotor integrations. (shrink)

The originality of Glenberg's theoretical account lies in the claim that memory works in the service of physical interaction with the three-dimensional world. Little consideration is given, however, to the role of memory in action. We present and discuss data on spatial memory for action. These empirical data constitute the first step of reasoning about the link between memory and action, and allow several aspects of Glenberg's theory to be tested.

A further step in Pylyshyn's discontinuity thesis is to examine the penetrability of haptic (tactual-kinesthetic) perception. The study of the perception of orientation and the “oblique effect” (lower performance in oblique orientations than in vertical–horizontal orientations) in the visual and haptic modalities allows this question to be discussed. We suggest that part of the visual process generating the visual oblique effect is cognitively impenetrable, whereas all haptic processes generating the haptic oblique effect are cognitively penetrable.

Dienes & Perner's (D&P's) target articles proposes an analysis of explicit knowledge based on a progressive transformation of implicit into explicit products, applying this gradient to different aspects of knowledge that can be represented. The goal is to integrate a philosophical concept of knowledge with relevant psychophysical and neuropsychological data. D&P seem to fill an impressive portion of the gap between these two areas. We focus on two examples where a full synthesis of theoretical and empirical data seems difficult to (...) establish and would require further refinement of the model: action representation and the closely related consciousness of action, which is in turn related to self-consciousness. (shrink)

A visual analogue, two-route model of somatosensory processing is advanced in this commentary. Touch for perception is seen as separate from, although interconnected with, touch for action. Separate modules are additionally proposed for internal (body) and external (object-related) somatosensation. Here we ask whether dissociation (divide) guarantees better efficiency (impera) in terms of the heuristic model within the somatosensory modality and across modalities.

Plamondon's kinematic theory is very powerful from a descriptive point of view. Unfortunately, the fact that it neglects some fundamental features of the motor system, such as nonlinear inertial torque interactions or joint redundancies, limits its explanatory power and biological validity. As a consequence, the data presented by Plamondon & Alimi should be analyzed and interpreted with caution. There appears to be a gap between the observations reported by the authors and some of the conclusions they draw.

The concept of a conservative control strategy minimizing the number of degrees of freedom used is criticised with reference to 3-D simple reaching and grasping experiments. The vector error in a redundant system would not be the prime controlled variable, but rather the posture for reaching, as exemplified by nearly straight displacements in joint space as opposed to curved ones in task space.

Some data concerning visual illusions are hardly compatible with the perception–action model, assuming that only the perception system is influenced by visual context. The planning–control dichotomy offers an alternative that better accounts for some controversy in experimental data. We tested the two models by submitting the patient I. G. to the induced Roelofs effect. The similitude of the results of I. G. and control subjects favoured Glover's model, which, however, presents a paradox that needs to be clarified.

Is there any ecological purpose in assuming that perception for action exists only through a global array of energy? Unlike Stoffregen & Bardy, who assume that behavior consists of movements, we would argue that behavior consists of a stable coupling between perception and action achieved through experience in an adaptive context. Determining target position in an aiming manual task and temporal control of impact movement illustrate that patterns of energy used for action are task-dependent.

Prism Adaptation is a useful method to study the mechanisms of sensorimotor adaptation. After-effects following adaptation to the prismatic deviation constitute the probe that adaptive mechanisms occurred, and current evidence suggests an involvement of the cerebellum at this level. Whether after-effects are transferable to another task is of great interest both for understanding the nature of sensorimotor transformations and for clinical purposes. However, the processes of transfer and their underlying neural substrates remain poorly understood. Transfer from throwing to pointing is (...) known to occur only in individuals who had previously reached a good level of expertise in throwing, not in novices. The aim of this study was to ascertain whether anodal stimulation of the cerebellum could boost after-effects transfer from throwing to pointing in novice participants. Healthy participants received anodal or sham transcranial direction current stimulation of the right cerebellum during a PA procedure involving a throwing task and were tested for transfer on a pointing task. Terminal errors and kinematic parameters were in the dependent variables for statistical analyses. Results showed that active stimulation had no significant beneficial effects on error reduction or throwing after-effects. Moreover, the overall magnitude of transfer to pointing did not change. Interestingly, we found a significant effect of the stimulation on the longitudinal evolution of pointing errors and on pointing kinematic parameters during transfer assessment. These results provide new insights on the implication of the cerebellum in transfer and on the possibility to use anodal tDCS to enhance cerebellar contribution during PA in further investigations. From a network approach, we suggest that cerebellum is part of a more complex circuitry responsible for the development of transfer which is likely embracing the primary motor cortex due to its role in motor memories consolidation. This paves the way for further work entailing multiple-sites stimulation to explore the role of M1-cerebellum dynamic interplay in transfer. (shrink)

Thales the Measurer offers a comprehensive and iconoclastic account of Thales of Miletus, considering the full extent of our evidence to build a new picture of his intellectual interests and activity. Thales is most commonly associated with the claim that 'everything is water', but closer examination of the evidence that we have suggests that he could not have said anything of the sort. His real interests, and his real innovations, lay in challenges of quantitative measurement, especially measurements related to the (...) movement of the sun. In this he had no predecessors - and, for centuries to follow, no real successors either. This book is of interest for scholars in the history of philosophy, science, and life sciences. It is aimed especially at researchers in the field, but is also accessible to students and a more general readership. (shrink)

Présenter un aperçu de la « mystique chrétienne médiévale » n’est possible qu’en la situant brièvement dans l’histoire de la « mystique » en Occident. Le terme n’est pas dénué d’ambiguïté. Apparaissant dans le contexte des religions à mystères, la mystique évolue vers une expérience silencieuse que les mots ne peuvent capter, avant de désigner des phénomènes anormaux décrits dans une rhétorique de l’étrange. Par rapport à la littérature moderne, les textes médiévaux sont très sobres. Faisant à écho à la (...) théologie mystique de Denys l’Aréopagite (ve-vie s.), ils présentent une voie d’union à l’Un en deçà des mots et des concepts. Il ne suffit pas de connaître (mathein) Dieu par un savoir notionnel, il faut en faire l’expérience, « en pâtir » (pathein). Ce « pâtir Dieu » sera repris par Maître Eckhart (1260-1328), le chef de file de la mystique rhénane. (shrink)

Why does something please us? Is there right and wrong in aesthetics? What is the value of art? What do philosophical and aesthetic problems have in common? Wittgenstein worked intensively on these and other questions and wrote of the strange resemblance between aesthetics and philosophy. This study shows how Wittgenstein s arguments have substantially contributed to explaining systematic questions in aesthetics.".

Le constat est maintenant partout: la puissance du fondamentalisme religieux, la montee des populismes de droite comme de gauche, le discredit de la classe politique, le rejet de la construction europeenne, rendent caducs les schemas anciens. En particulier l'idee que la democratie, a force de bienveillance, peut tolerer toutes les differences, toutes les croyances. Oui! Il y a des croyances insupportables et intolerables. Non! Le populisme n'est pas une illusion qui se dissipera d'elle-meme avec un peu de pedagogie et de (...) bonne volonte. Non! La politique internationale n'obeit pas aux chartes du droit international. Il faut denoncer la tyrannie des bons sentiments, la politique de l'emotion et de la compassion. Non que la bienveillance soit un sentiment indigne, mais nous devons cesser de croire qu'on peut batir sur elle une communaute politique. (shrink)

« Déconstruire l’idée que l’animal serait sans intelligence, sans conscience, sans langage, etc., n’est qu’une étape vers une entreprise plus essentielle : la reconnaissance de la richesse des mondes animaux, dans leur diversité, sans céder à la tentation de les hiérarchiser. Tel est l’esprit qui m’anime dans cet ouvrage. Parce que les animaux, humains ou non humains, ne sont pas les jouets passifs du monde qui les entoure et qu’ils en sont au contraire les créateurs actifs, parce qu’ils sont porteurs (...) d’une vision du monde, je les considère comme des philosophes. Ils ne se contentent pas de percevoir passivement leur environnement, ils l’élaborent, ils l’anticipent. Ils donnent du sens aux choses. » Y. C. Biologiste et journaliste scientifique, Yves Christen préside la Fondation Ipsen. Il a notamment publié Le Peuple léopard, Les Surdoués du monde animal et L’animal est-il une personne?. (shrink)

Comment les scientifiques peuvent-ils participer aux controverses dont font l’objet certains développements techniques? En injectant une sensibilité littéraire dans cette participation. Telle est la thèse de cet ouvrage. Au travers d’illustrations telles qu’un poème d’Henri Michaux ou une déclaration de faucheur volontaire d’OGM, Yves Citton examine comment les scientifiques peuvent participer aux débats publics et civils et contribuer à sortir de la confrontation des disciplines, des domaines et des opinions.

Le monde qui nous est commun et connu disparaît face à l'accélération technologique et à l'immensité de ce qui reste à découvrir. Le présent quant à lui est devenu envahissant et s'abîme à chaque instant dans l'immédiateté. La société contemporaine cesse d'être un projet identifié et identifiable. Nous en sommes réduits à essayer d'apprendre le monde plutôt que d'imaginer demain. L'éthique est l'un des outils à notre disposition pour regarder et comprendre le monde nouveau, celui d'une modernité consciente. Malmené par (...) la crise, les angoisses, les références à un passé définitivement révolu, les discours à la mode et la pensée unique, le concept éthique requiert d'être dépoussiéré, repensé, actualisé. Cet essai est un appel à réfléchir et travailler pour, pierre après pierre, reconstruire un principe d'espérance pour demain. (shrink)

Que peut nous apporter aujourd’hui la lecture des Idéologues, ces penseurs qui ont reconfiguré le champ des savoirs au début du XIXe siècle? La mise au jour d’un moment idéologique. Ce moment est celui qui voit une radicalité des Lumières se scinder entre divers branchements disciplinaires, entre diverses conceptions de la subjectivité et de l’émancipation. Le moment idéologique est un moment de passage, mais surtout de décantation. On y voit émerger, quoiqu’encore entremêlés et solidaires, ce que nous sommes habitués à (...) distinguer : Lumières et romantisme, rationalisme et sentiment, radicalité et conservatisme, nécessité et volontarisme, colonialisme et soif d’altérité, science et littérature. Les dix chapitres de cet ouvrage ont en commun de visiter ce moment idéologique à partir de questions concrètes, analysées sur des objets textuels précisément circonscrits : une fausse polémique, un cours d’histoire, une analogie hydraulique, des théories de l’imagination, des épisodes de réminiscence involontaire, un voyage à Alexandrie, un projet d’alphabet universel, une explication de l’amitié, une réécriture romanesque de la folle « science des idées ». C’est à partir de ces cas particuliers que prend forme une image d’ensemble du moment idéologique, où se révèlent à la fois la reconfiguration des champs du savoir et ce que cette reconfiguration a occulté : l’inséparabilité de ce qui devient alors, d’un côté, « la littérature » et, de l’autre, « les sciences » (de l’homme) – le moment idéologique nous faisant voir que ce sont les deux faces d’une même pièce. (shrink)