Lightness effects in Delboeuf and Ebbinghaus size-contrast illusions

We examined lightness effects observed in Delboeuf and Ebbinghaus size-contrast illusions. Results of four experiments are reported. Experiment 1 was conducted with Delboeuf-like stimuli and shows that the disk that appears bigger appears either lighter or darker than the disk that appears smaller, depending on the contrast polarity between disks and background. Experiment 2 shows that the direction of these lightness effects is not influenced by the luminance of the size-contrast inducers. Experiment 3 shows that a similar lightness effect is also observed in modified Ebbinghaus size-contrast displays. Experiment 4 tested the presence of the size-contrast illusion in the stimuli used in experiments 2 and 3.     

Does terrain slope really dominate goal searching?

If you can locate a target by using one reliable source of information, why would you use an unreliable one? A similar question has been faced in a recent study on homing pigeons, in which, despite the presence of better predictors of the goal location, the slope of the floor in an arena dominated the searching process. This piece of evidence seems to contradict straightforward accounts of associative learning, according to which behavior should be controlled by the stimulus that best predicts the reward, and has fueled interest toward one question that, to date, has received scarce attention in the field of spatial cognition: how are vertical spaces represented? The purpose of this communication is to briefly review the studies on this issue, trying to determine whether slope is a special cue--driving behavior irrespective of other cues--or simply a very salient one.     

Eye gaze cannot be ignored (but neither can arrows)

Recent studies have tried to shed light on the automaticity of attentional shifts triggered by gaze and arrows with mixed results. In the present research, we aimed at testing a strong definition of resistance to suppression for orienting of attention elicited by these two cues. In five experiments, participants were informed with 100% certainty about the future location of a target they had to react to by presentation of either a direction word at the beginning of each trial or instructions at the beginning of each block. Gaze and arrows were presented before the target as uninformative distractors irrelevant for the task. The results showed similar patterns for gaze and arrows-namely, an interference effect when the distractors were incongruent with the upcoming target location. This suggests that the orienting of attention mediated by gaze and arrows can be considered as strongly automatic.     

Idiolects and Language

The present paper is intended to analyse from a theoretical point of view the relationships between natural language and idiolects in the context of communication by means of the Davidson–Dummett controversy on the nature of language. I will explore from a pragmatic point of view the reliability of an alternative position inspired by the recent literalism/contextualism debate in philosophy of language in order to overcome some limitations of Dummett’s and Davidson’s perspectives on language, idiolects and communication.     

Effects of predation risk on the sensory asymmetries and defensive strategies of Bufotes balearicus tadpoles

Animal Cognition - Lateralization consists of the differential use of bilateral organs or limbs and is well described in many taxa and in several contexts. Common ecological frameworks where it can...     

Analyse d'une Sepreuve d'image mentale chez des adolescents presentant des difficultis d'apprentissage scolaire1

Le travail faisant l'objet de cet article s'inscrit dans le cadre d'un programme de recherche plus large qui s'intéresse à la variabilité individuelle des processus cognitifs et à son influence éventuelle sur les lois générates du développement de l'intelligence. Une partie des résultats a déjàété présentée dans d'autres publications auxquelles le lecteur pourra se référer pour plus de détails (par exemple, Rieben et al., 1983). Nous nous contenterons de les décrire brièvement afin d'introduire l'aspect spécifique sur lequel nous nous sommes centrées ici.     

The Theoretical Reformer: on Husserl’s Plato (Husserl and the Figures of the History of Philosophy)

ABSTRACT

The present research contributes to the elucidation of an important aspect of Husserl’s interpretation of the history of philosophy, that is, his reading of the beginning of Western thought. In particular, it aims to clarify the sense in which Husserl deems Plato the father of the idea itself of philosophy as a science. As will be maintained, Husserl thinks of Socrates and Plato together as providing the first reform of philosophy, whose overall goal is to give reason (Vernunft) a universal method of self-justification against the general skepticism of the sophists. The analysis will be both systematically and historically oriented, for, it will try to both reconstruct Husserl’s interpretation of the background against which Plato first introduces the idea of philosophy as a science, and to show that what is truly at stake for Husserl is the nature of philosophy itself.     

Righting behaviour in the European pond turtle (Emys orbicularis): relations between behavioural and morphological lateralization

Animal Cognition - Lateralization represents a key property of many behavioural traits, with the right and left sides of the brain providing different and integrative functions. Common ecological...