The right hemispheric dominance for face perception in preschool children depends on the visual discrimination level

The developmental origin of human adults’ right hemispheric dominance in response to face stimuli remains unclear, in particular because young infants’ right hemispheric advantage in face‐selective response is no longer present in preschool children, before written language acquisition. Here we used fast periodic visual stimulation (FPVS) with scalp electroencephalography (EEG) to test 52 preschool children (5.5 years old) at two different levels of face discrimination: discrimination of faces against objects, measuring face‐selectivity, or discrimination between individual faces. While the contrast between faces and nonface objects elicits strictly bilateral occipital responses in children, strengthening previous observations, discrimination of individual faces in the same children reveals a strong right hemispheric lateralization over the occipitotemporal cortex. Picture‐plane inversion of the face stimuli significantly decreases the individual discrimination response, although to a much smaller extent than in older children and adults tested with the same paradigm. However, there is only a nonsignificant trend for a decrease in right hemispheric lateralization with inversion. There is no relationship between the right hemispheric lateralization in individual face discrimination and preschool levels of readings abilities. The observed difference in the right hemispheric lateralization obtained in the same population of children with two different paradigms measuring neural responses to faces indicates that the level of visual discrimination is a key factor to consider when making inferences about the development of hemispheric lateralization of face perception in the human brain.     

Frontal Lobe Function and Pain in the Elderly

We review the literature on pain and aging and conclude that evidence supports a hypothesis that right frontal cortex contributes to the mediation of the chronic pain experience in elderly persons with chronic pain syndromes. Evidence for the right frontal pain hypothesis comes from clinical, neurocognitive, and neuroimaging studies, which implicate right inferior and orbitofrontal cortex in (1) the persistent pain experience, (2) negative emotional states, (3) retrieval of negative emotional and autobiographical memories, (4) regulation of autonomic arousal, and (5) regulation of attentional and pain functions of the anterior cingulate region. Right frontal dysfunction is also implicated in the effects of cognitive aging. If right frontal neurocognitive systems are affected in cognitively impaired elderly, and if (by hypothesis) the right frontal cortex also plays a major role in the experience of chronic pain, then cognitively impaired elderly with right frontal dysfunction should be protected to some extent from persistent pain syndromes. Available evidence supports this proposition.     

A comparative study on GaN luminescence under/after inductively coupled plasma exposure

GaN luminescence, induced by ultraviolet light under/after inductively coupled plasma exposure, has been measured in situ and ex situ. After the plasma exposure, both near-band edge (NBE) and yellow luminescence (YL) intensities decrease. The decay times of NBE and YL in the in situ measurement are shorter than those of the ex situ measurement on account of the temperature rise induced by the plasma. On the other hand, with increasing plasma power, the decay times decrease. It is considered that this decrease is strongly related to non-radiative defects introduced by the Ar plasma. The results suggest that in situ photoluminescence monitoring can be used to reveal plasma-induced damage at GaN surfaces.     

L’anormalité du dommage : une notion juridique stabilisée ?

Medical liability, in accordance with liability law, is traditionally based on the triad of operative event, causal link and damage. The emergence of systems of no-fault liability gave rise to the concept of abnormal damage, which is a necessary condition for liability. In terms of medical liability, in 1958 the administrative courts ruled that this criterion was necessary in order to compensate medical damage in situations of liability for alleged misconduct, then from 1990 in situations of no-fault liability. This condition was extended to compensate medical hazard from 1993. The Court of Cassation refused to adopt a no-fault liability system, leading to unequal treatment. Thus, the law of March 4, 2002 created a system which, in situations of no-fault liability, allowed national solidarity to be engaged in the event of abnormal damage. However, the legislation did not clearly set out the character of this abnormality, and jurisprudential hesitation over this criterion has made compensation uncertain. In 2014, the administrative and judicial courts clarified their jurisprudence by adopting a more specific definition of this criterion of abnormality. However, a very restrictive view taken of this criterion means that many victims now risk being excluded from the scope of compensation. As such, this jurisprudential stability is perhaps but temporary.     

Covert reading of letters in a case of global alexia

This study describes the case of a global alexic patient with a severe reading deficit affecting words, letters and Arabic numbers, following a left posterior lesion. The patient (VA) could not match spoken letters to their graphic form. A preserved ability to recognize shape and canonical orientation of letters indicates intact access to the representation of letters and numbers as visual objects. A relatively preserved ability to match lowercase to uppercase letters suggests partially spared access to abstract letter identities independently of their visual forms. The patient was also unable to match spoken letters and numbers to their visual form, indicating that she could not access the graphemic representations of letters from their phonological representations. This pattern of performance suggests that the link between graphemic and phonological representations is disrupted in this patient. We hypothesize that VA’ residual reading abilities are supported by the right hemisphere.     

The role of the right hemisphere in speech act comprehension

In this research the role of the RH in the comprehension of speech acts (or illocutionary force) was examined. Two split-screen experiments were conducted in which participants made lexical decisions for lateralized targets after reading a brief conversation remark. On one-half of the trials the target word named the speech act performed with the preceding conversation remark; on the remaining trials the target did not name the speech act that the remark performed. In both experiments, lexical decisions were facilitated for targets representing the speech act performed with the prior utterance, but only when the target was presented to the left visual field (and hence initially processed by the RH) and not when presented to the right visual field. This effect occurred at both short (Experiment 1: 250 ms) and long (Experiment 2: 1000 ms) delays. The results demonstrate the critical role played by the RH in conversation processing.     

From left to right: Processing acronyms referring to names of political parties activates spatial associations

In line with previous studies, showing that abstract concepts like “power” or “god” implicitly activate spatial associations, in the present study we hypothesized that spatial associations are coactivated during the processing of acronyms referring to names of political parties as well. In four studies, it was found that the reading of these acronyms was accompanied by the implicit activation of spatial left–right associations. That is, participants responded faster to left-wing parties by means of a left-hand button press and vice versa for right-wing parties (Experiments 1 to 3), and participants responded faster when a political acronym was presented at the side of the screen corresponding to the political orientation of the acronym (Experiment 4). Interestingly, a correlation was observed between the effect size for left-wing parties and participants' political preferences, suggesting that the reaction time effects reflect the perceived distance of a party to one's own political orientation. Together these findings indicate that spatial representations activated in response to political acronyms do not simply reflect lexical–semantic associations or spatial metaphors, but representations of parties' political orientation relative to one's own sociopolitical position.     

No trust on the left side: Hemifacial asymmetries for trustworthiness and emotional expressions

People can discriminate cheaters from cooperators by their appearance. However, successful cheater detection can be thwarted by a posed smile, which cheaters display with greater emotional intensity than cooperators. The present study investigated the underlying neural and cognitive mechanisms of a posed smile, which cheaters use to conceal their anti-social attitude, in terms of hemifacial asymmetries of emotional expressions. Raters (50 women and 50 men) performed trustworthiness judgments on composite faces of cheaters and cooperators, operationally defined by the number of deceptions in an economic game. The left–left composites of cheaters were judged to be more trustworthy than the right–right composites when the models posed a happy expression. This left-hemiface advantage for the happy expression was not observed for cooperators. In addition, the left-hemiface advantage of cheaters disappeared for the angry expression. These results suggest that cheaters used the left hemiface, which is connected to the emotional side of the brain (i.e., the right hemisphere), more effectively than the right hemiface to conceal their anti-social attitude.     

Midgap photon effects in As2S3 glass

Photo-induced phenomena in glasses excited by two-photon absorption have been studied and compared with those produced by bandgap illumination. The two-photon excitation of As₂S₃ gives a refractive-index increase, unaccompanied by photodarkening. Raman-scattering spectra show that the excitation increases the density of ‘wrong’ bonds. These observations are discussed and compared with photo-induced changes in SiO₂.