Electrophysiological correlates of the composite face illusion: Disentangling perceptual and decisional components of holistic face processing in the human brain

When the bottom halves of two faces differ, people’s behavioral judgment of the identical top halves of those faces is impaired: they report that the top halves are different, and/or take more time than usual to provide a response. This behavioral measure is known as the composite face effect (CFE) and has traditionally been taken as evidence that faces are perceived holistically. Recently, however, it has been claimed that this effect is driven almost entirely by decisional, rather than perceptual, factors ( Richler, Gauthier, Wenger, & Palmeri, 2008). To disentangle the contribution of perceptual and decisional brain processes, we aimed to obtain an event-related potential (ERP) measure of the CFE at a stage of face encoding ( Jacques & Rossion, 2009) in the absence of a behavioral CFE effect. Sixteen participants performed a go/no-go task in an oddball paradigm, lifting a finger of their right or left hand when the top half of a face changed identity. This change of identity of the top of the face was associated with an increased ERP signal on occipito-temporal electrode sites at the N170 face-sensitive component (∼160 ms), the later decisional P3b component, and the lateralized readiness potential (LRP) starting at ∼350 ms. The N170 effect was observed equally early when only the unattended bottom part of the face changed, indicating that an identity change was perceived across the whole face in this condition. Importantly, there was no behavioral response bias for the bottom change trials, and no evidence of decisional biases from electrophysiological data (no P3b and LRP deflection in no-go trials). These data show that an early CFE can be measured in ERPs in the absence of any decisional response bias, indicating that the CFE reflects primarily the visual perception of the whole face.     

Education and interactivism: Levels of interaction influencing learning processes

The aim of this paper is to explore some consequences of interactivism within learning situations. Since the original interactivist point of view focused on the Subject/Object relationship, much research has stressed the importance of the non-individualistic aspects of learning, and we have found it revealing to point out the mediation processes occurring inside and outside the S/O relationship (e.g. mediation involving cultural context or artifacts). We have combined different learning theory frameworks, chosen for their complementary conceptions of learning, with a view toward describing the system of interactions involved in teaching/learning processes.The cultural-historical approach to learning insists on the fundamental role of socially constructed tools in human development and education (Vygotsky). Clot and Engeström consider educational institutions as working communities that constrain Subject/Object interaction by rules and habits. Chevallard describes the implications of various categories of actors in the definition of curricula. Within the classroom, besides the obvious mutual influences of individual participants, problems to be solved, as organized by the teacher, influence the attitude of the learner towards the knowledge to be acquired (Brousseau). Furthermore, these situations contain multiple artifacts aimed at facilitating the acquisition of the skills necessary in order to use artifacts outside of the educational context (Rabardel & Bourmaud). Finally, Vergnaud suggests that it is more fruitful to consider the relationship between scheme and situation rather than that between subject and object.We will consider how these various levels of mediation shape the Subject/Object relationship and the learning process.     

Effects of study list composition on the word frequency effect and metacognitive attributions in recognition memory

In two experiments, study-list composition was manipulated and its impact was observed on metacognitive judgements associated with recognition hits (Hs) and false alarms (FAs). Both studies involved recognition of high-frequency (HF) and low-frequency (LF) words, and focused on the FA portion of the word frequency effect. Our hypothesis was that participants can actively reject items that are distinctive from the study list, and that this effect may be strong enough to overcome the FA word frequency effect. Experiment 1 manipulated list composition with a conjunctive rule and Experiment 2 varied it by having participants study either HF or LF items prior to a test consisting of words of both frequencies. In each study H rate, FA rate, and metacognitive attributions underlying recognition decisions were investigated. In both studies, participants reported rejecting test items predominantly through a process of active rejection, which was more often reported for LF items. This effect was strong enough to reverse the FA portion of the word frequency effect in Experiment 2, but not Experiment 1. The results are discussed in terms of metacognitive rejection mechanisms in recognition memory.     

Action blindness in response to gradual changes

The goal of this study is to characterize observers’ abilities to detect gradual changes and to explore putative dissociations between conscious experience of change and behavioral adaptation to a changing stimulus. We developed a new experimental paradigm in which, on each trial, participants were shown a dot pattern on the screen. Next, the pattern disappeared and participants had to reproduce it. In some conditions, the target pattern was incrementally rotated over successive trials and participants were either informed or not of this change. We analyzed both awareness of the changes and the dynamics of behavioral adaptation, in a way that makes it possible to assess both variability and accuracy as they change over time. Results indicate a dissociation between change awareness and behavioral adaptation to the changes, and support the notion that unconscious representations of visual stimuli are more precise and detailed than previously suggested. We discuss the implications of these results for theories of change detection.     

Rational Choice Virtues

In this essay, I review some results that suggest that rational choice theory has interesting things to say about the virtues. In particular, I argue that rational choice theory can show, first, the role of certain virtues in a game-theoretic analysis of norms. Secondly, that it is useful in the characterization of these virtues. Finally, I discuss how rational choice theory can be brought to bear upon the justification of these virtues by showing how they contribute to a flourishing life. I do this by discussing one particular example of a norm - the requirement that agents to honor their promises of mutual assistance - and one particular virtue, trustworthiness.     

The Role of Occupational Characteristics and Occupational Imbalance in Explaining Well-being

One of the key factors for promoting well-being lies in balancing one’s daily life occupations and the nature of these occupations. Occupation refers to a group of everyday life goal-directed activities which may be associated to any life domain, not necessarily work, such as leisure, education, or self-care. Yet it is not clear what constitutes occupational imbalance, and its association to other factors has not been examined systematically. This study proposed and tested a theoretical model for specifying the structural relationships between occupational imbalance, occupational characteristics, personality and well-being. 288 working adults completed the following questionnaires: Inter-goal Relations Questionnaire (occupational imbalance), Personal Projects Analysis (occupational characteristics), the Big Five Inventory (personality traits) and the Satisfaction with Life Scale (well-being). Twenty-five models were tested using structural equation modeling. All the models fit the data well. Occupational characteristics, with the exception of stress, served as significant mediators between personality and well-being, yet occupational imbalance did not play a significant role across all models. Our findings provide substantial support for the importance of occupation to well-being, however occupational imbalance is still an elusive concept that requires further investigation theoretically and empirically.     

How does the strength of the relationships between cognitive abilities evolve over the life span for low-IQ vs high-IQ adults?

The present study was designed to examine how the correlations between cognitive abilities evolve during adulthood. Data from 1104 participants on the French version of the Wechsler Adult Intelligence Scale-Third Edition were analyzed. The entire sample was divided into four age groups (16–24 years; 25–44 years; 45–69 years and 70–89 years), which were themselves split into two IQ-levels using the mean standard score on Vocabulary and Block Design. For every age group, the mean correlation between subtest scores of low-IQ participants was higher than that of high-IQ participants. There was also no interaction between age and IQ for the strength of subtest relationships. Indeed, the effect sizes of correlation differences between low- and high-IQ participants appeared to be relatively constant across age. A general developmental schema of how the strength of correlations between cognitive abilities of low- and high-IQ individuals evolves during the entire life span is sketched in the discussion.     

Newborns' face recognition is based on spatial frequencies below 0.5 cycles per degree

A critical question in Cognitive Science concerns how knowledge of specific domains emerges during development. Here we examined how limitations of the visual system during the first days of life may shape subsequent development of face processing abilities. By manipulating the bands of spatial frequencies of face images, we investigated what is the nature of the visual information that newborn infants rely on to perform face recognition. Newborns were able to extract from a face the visual information lying from 0 to 1 cpd (Experiment 1), but only a narrower 0-0.5 cpd spatial frequency range was successful to accomplish face recognition (Experiment 2). These results provide the first empirical support of a low spatial frequency advantage in individual face recognition at birth and suggest that early in life low-level, non-specific perceptual constraints affect the development of the face processing system.     

Value-based accounts of normative powers and the wishful thinking objection

Philosophical Studies - Normative powers like promising allow agents to effect changes to their reasons, permissions and rights by the means of communicative actions whose function is to effect...