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Human performance at categorizing natural visual images surpasses automatic algorithms, but how and when this function arises and develops remain unanswered. We recorded scalp electrical brain activity in 4–6 months infants viewing images of objects in their natural background at a rapid rate of 6 images/second (6 Hz). Widely variable face images appearing every 5 stimuli generate an electrophysiological response over the right hemisphere exactly at 1.2 Hz (6 Hz/5). This face-selective response is absent for phase-scrambled images and therefore not due to low-level information. These findings indicate that right lateralized face-selective processes emerge well before reading acquisition in the infant brain, which can perform figure-ground segregation and generalize face-selective responses across changes in size, viewpoint, illumination as well as expression, age and gender. These observations made with a highly sensitive and objective approach open an avenue for clarifying the developmental course of natural image categorization in the human brain. DOI: http://dx.doi.org/10.7554/eLife.06564.001, eLife digest Putting names to faces can sometimes be challenging, but humans are generally extremely good at recognising faces. Computers, on the other hand, often find it difficult to categorize a face as a face. Indeed, a major challenge in face recognition arises because faces come in many different shapes and sizes. Moreover, both the lighting conditions and the orientation of the head can change, which makes the challenge even more difficult. Young infants also show a preference for pictures of human faces over nonsense images, which suggests that the ability to recognise faces is at least partly hard-wired. Neuroimaging studies have revealed that face recognition depends on activity in specific regions of the right hemisphere of the brain, and adults who sustain damage to these regions lose their face recognition skills. De Heering and Rossion have now provided the first evidence that the right hemisphere is specialized for distinguishing between natural images of faces and ‘non-face objects’ in infants as young as 4 to 6 months. By using scalp electrodes to record electrical activity in the brain as the infants viewed images on a screen, De Heering and Rossion showed that photographs of human faces triggered a distinct pattern of electrical activity in the right hemisphere: this pattern was clearly different to the patterns triggered by photographs of animals or objects. A consistent response was triggered by faces of different genders and expressions, and by faces presented from various viewpoints and under different lighting conditions. In a control experiment, De Heering and Rossion demonstrated that low-level visual features such as differences in luminance or contrast do not contribute to this selective response to faces. These results argue against the idea that face perception only becomes assigned to the right hemisphere of the brain when children learn to read (that is, when language processing begins to occupy parts of the left hemisphere). By generating significant responses in a short period of time (just five minutes or less), the protocol developed by De Heering and Rossion has the potential to prove very useful to researchers investigating developmental changes to the perception of visual images during childhood. DOI: http://dx.doi.org/10.7554/eLife.06564.002

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People tend to perceive identical top halves (i.e. above the nose) of two face stimuli as being different when they are aligned with distinct bottom halves. This face composite illusion has been demonstrated almost 20 years ago (Young et al., 1987), and is generally considered as the most compelling evidence that facial features are integrated into a holistic representation. Here, we recorded eye movements during the face composite effect, i.e. when the top and the bottom parts of a composite face stimulus are integrated into a single holistic face representation. The behavioral results showed a strong face composite effect when subjects maintained fixation to the top part of the face stimulus. Fixation sites and eye movements were virtually identical when the top and bottom parts were aligned (composite illusion) or misaligned (no illusion), indicating that holistic face processing can be independent of gaze behavior. These findings reinforce the view that holistic representations of individual faces can be extracted early on from low spatial frequency analysis, independently of overt attention.

The European Union has played an important role in international efforts to help the Central and Eastern European nuclear sector to improve the level of safety of their power plants. This is in line with the 1992 G7 summit which called for the early closure of the older, less safe Soviet design reactors, namely the VVER-440/ 230 and RBMK-type reactors. The enlargement process initiated in 1997 added a new dimension which was reinforced in Agenda 2000 which put into a political perspective the issue of nuclear safety in the countries applying for accession in the EU. At the end of 1999, the decision was taken between the European Commission and the three countries operating those reactors which were deemed non-upgradable, to close those reactors. This paper looks at the key issues surrounding accession and the nuclear industry, what progress has been made to date and what assistance is needed in the future.

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.

Publiees a Xining (Chine) en 2007, Joies et peines de l’enfant Naktsang, un temoignage historique sans precedent sur les annees 1950 en Amdo (nord-est du Tibet), sont tres vite devenues un best-seller du marche litteraire local. Contrairement aux pratiques dominant l’ecriture du tibetain, le texte entremele les registres litteraire et oral, mettant les dialectes pastoraux par ecrit « tels quels ». L’ethnographie des experiences de lecture et des receptions de l’ouvrage permet d’analyser la diversite des appreciations formulees a l’egard de cette ecriture atypique, pour degager certaines des sources de la justesse de ton qu’un grand nombre de lecteurs reconnait a l’enfant Naktsang.

This article examines the relationships between administrators and the administered within the framework of local development brokerage practices directed at setting up running water systems for domestic consumption in Tibetan rural areas of Qinghai Province. Split between several locations, the activities of the brokers entail finding agreements and compromises in various forms with a variety of interlocutors: local government, the recipients of the project – and also the deities.

In two experiments, we investigated whether adults use holistic processing even for faces that are grossly distorted because their eyes have been moved asymmetrically to violate the common layout of a face (distorting its first-order relations). To this end we used a compelling demonstration that faces are processed as wholes, the composite-face effect. Specifically, adults judged the similarity of sequentially presented top halves of normal (original condition) and distorted faces with one eye (one-eye condition) or two eyes (two-eyes condition) shifted up by an abnormal amount. Trials were either blocked by type of distortion (experiment 1) or intermixed within the experiment (experiment 2). In both experiments, participants demonstrated a composite-face effect of the same magnitude in the three conditions, a pattern suggesting that they processed holistically even faces whose first-order relations were violated.

Patients treated for bilateral congenital cataract are later impaired on several hallmarks of adults' expertise with upright faces but report no problem with remembering faces. Here, we provide the first formal data on their face memory. We compared 12 adults with a history of visual deprivation from bilateral congenital cataracts to 24 age-matched controls with normal vision on their ability to recognize famous and recently learned faces, and on their subjective impression of their face memory. Bilateral congenital cataract patients demonstrated a prosopagnosic-like deficit, being slower and less accurate in recognizing both famous faces and recently learned faces, despite not differing on most questions about their impression of their face memory. Patients' results on three perceptual tasks (the composite face effect, the Benton test of recognizing faces through a change in point of view, and the Jane test of sensitivity to feature spacing) were also not correlated with their face memory deficits. These results suggest that early visual input is necessary not only for perceptual expertise in differentiating among unfamiliar upright faces, but also for normal accuracy in remembering the identity of individual faces.

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Conventional processing of synthetic aperture sonar (SAS) data is equivalent to a two-dimensional matched filter operation. In principle, two-dimensional deconvolution improves the resolution of the processed image. However, its direct implementation is generally impractical, due to numerical problems. The paper discusses the development of iterative algorithms that efficiently perform the deconvolution of broadband synthetic aperture data and gives examples of their application. It is concluded that, in many cases, the proposed approach is preferable to more classical solutions. >

Whether the development of face recognition abilities truly reflects changes in how faces, specifically, are perceived, or rather can be attributed to more general perceptual or cognitive development, is debated. Event-related potential (ERP) recordings on the scalp offer promise for this issue because they allow brain responses to complex visual stimuli to be relatively well isolated from other sensory, cognitive and motor processes. ERP studies in 5- to 16-year-old children report large age-related changes in amplitude, latency (decreases) and topographical distribution of the early visual components, the P1 and the occipito-temporal N170. To test the face specificity of these effects, we recorded high-density ERPs to pictures of faces, cars, and their phase-scrambled versions from 72 children between the ages of 4 and 17, and a group of adults. We found that none of the previously reported age-dependent changes in amplitude, latency or topography of the P1 or N170 were specific to faces. Most importantly, when we controlled for age-related variations of the P1, the N170 appeared remarkably similar in amplitude and topography across development, with much smaller age-related decreases in latencies than previously reported. At all ages the N170 showed equivalent face-sensitivity: it had the same topography and right hemisphere dominance, it was absent for meaningless (scrambled) stimuli, and larger and earlier for faces than cars. The data also illustrate the large amount of inter-individual and inter-trial variance in young children's data, which causes the N170 to merge with a later component, the N250, in grand-averaged data. Based on our observations, we suggest that the previously reported "bi-fid" N170 of young children is in fact the N250. Overall, our data indicate that the electrophysiological markers of face-sensitive perceptual processes are present from 4 years of age and do not appear to change throughout development., info:eu-repo/semantics/published

The paper presents results from active sonar trials of the detection of icebergs (both in free water and ice locked) at 36 kHz. It is observed that the average target strength of the bergs, can be approximately expressed as a function of their estimated mass by a simple expression having physical plausibility. Further, observations of the echo duration, maximum detection range, sonar self‐noise and under ice reverberation are presented and discussed.

Background: Using the well-known composite illusion as a marker of the holistic perception of faces, we tested how prolonged visual experience with a specific population of faces (4- to 6-year-old children) modulates the face perception system in adulthood. Methodology/Prindpal Findings: We report a face composite effect that is larger for adult than children faces in a group of adults without experience with children faces ("children-face novices"), while it is of equal magnitude for adults and children faces in a population of preschool teachers ("children-face experts"). When considering preschool teachers only, we observed a significant correlation between the number of years of experience with children faces and the differential face composite effect between children and adults faces. Participants with at least 10 years of qualitative experience with children faces had a larger composite face effect for children than adult faces. Conclusions/Significance: Overall, these observations indicate that even in adulthood face processes can be reshaped qualitatively, presumably to facilitate efficient processing of the differential morphological features of the frequently encountered population of faces. © 2008 de Heering, Rossion., info:eu-repo/semantics/published