Pupil dilation reflects the social and motion content of faces.

Human facial features (eyes, nose, and mouth) allow us to communicate with others. Observing faces triggers physiological responses, including pupil dilation. Still, the relative influence of social and motion content of a visual stimulus on pupillary reactivity has never been elucidated. A total of 30 adults aged 18-33 years old were recorded with an eye tracker. We analysed the event-related pupil dilation in response to stimuli distributed along a gradient of social salience (non-social to social, going from objects to avatars to real faces) and dynamism (static to micro- to macro-motion). Pupil dilation was larger in response to social (faces and avatars) compared to non-social stimuli (objects), with surprisingly a larger response for avatars. Pupil dilation was also larger in response to macro-motion compared to static. After quantifying each stimulus' real quantity of motion, we found that the higher the quantity of motion, the larger the pupil dilated. However, the slope of this relationship was not higher for social stimuli. Overall, pupil dilation was more sensitive to the real quantity of motion than to the social component of motion, highlighting the relevance of ecological stimulations. Physiological response to faces results from specific contributions of both motion and social processing.

Sounds Pleasantness Ratings in Autism: Interaction Between Social Information and Acoustical Noise Level.

A lack of response to voices, and a great interest for music are part of the behavioral expressions, commonly (self-)reported in Autism Spectrum Disorder (ASD). These atypical interests for vocal and musical sounds could be attributable to different levels of acoustical noise, quantified in the harmonic-to-noise ratio (HNR). No previous study has investigated explicit auditory pleasantness in ASD comparing vocal and non-vocal sounds, in relation to acoustic noise level. The aim of this study is to objectively evaluate auditory pleasantness. 16 adults on the autism spectrum and 16 neuro-typical (NT) matched adults rated the likeability of vocal and non-vocal sounds, with varying harmonic-to-noise ratio levels. A group by category interaction in pleasantness judgements revealed that participants on the autism spectrum judged vocal sounds as less pleasant than non-vocal sounds; an effect not found for NT participants. A category by HNR level interaction revealed that participants of both groups rated sounds with a high HNR as more pleasant for non-vocal sounds. A significant group by HNR interaction revealed that people on the autism spectrum tended to judge as less pleasant sounds with high HNR and more pleasant those with low HNR than NT participants. Acoustical noise level of sounds alone does not appear to explain atypical interest for voices and greater interest in music in ASD.

Facial mask disturbs ocular exploration but not pupil reactivity.

Introduction: The COVID-19 pandemic has imposed to wear a face mask that may have negative consequences for social interactions despite its health benefits. A lot of recent studies focused on emotion recognition of masked faces, as the mouth is, with the eyes, essential to convey emotional content. However, none have studied neurobehavioral and neurophysiological markers of masked faces perception, such as ocular exploration and pupil reactivity. The purpose of this eye tracking study was to quantify how wearing a facial accessory, and in particular a face mask, affected the ocular and pupillary response to a face, emotional or not. Methods: We used videos of actors wearing a facial accessory to characterize the visual exploration and pupillary response in several occlusion (no accessory, sunglasses, scarf, and mask) and emotional conditions (neutral, happy, and sad) in a population of 44 adults. Results: We showed that ocular exploration differed for face covered with an accessory, and in particular a mask, compared to the classical visual scanning pattern of a non-covered face. The covered areas of the face were less explored. Pupil reactivity seemed only slightly affected by the mask, while its sensitivity to emotions was observed even in the presence of a facial accessory. Discussion: These results suggest a mixed impact of the mask on attentional capture and physiological adjustment, which does not seem to be reconcilable with its strong effect on behavioral emotional recognition previously described.

[Management of simple acute diverticulitis : Towards a "less is more" approach]. / Prise en charge de la diverticulite aiguë simple : vers une approche plus « less is more ¼.

Acute diverticulitis is the most common complication of diverticular disease, increasing in industrialized countries and in young people under 45 years of age. The modified Hinchey classification remains the most widely used and includes simple diverticulitis, i.e. localized inflammation without sepsis, and complicated diverticulitis from pericolic abscess to stercoral peritonitis. Recent studies recommend conservative management of uncomplicated forms. This article summarizes the management of simple acute left-sided diverticulitis based on the new recommendations and focusing on antibiotic treatment, outpatient or inpatient management and indications for colonoscopy.

La diverticulite aiguë est la complication la plus fréquente de la maladie diverticulaire. Son incidence est en augmentation dans les pays industrialisés, notamment chez les jeunes de moins de 45 ans. La classification de Hinchey modifiée reste la plus utilisée et comprend la diverticulite simple, inflammation localisée sans sepsis, et la diverticulite compliquée, de l'abcès péricolique jusqu'à la péritonite stercorale. Les récentes études favorisent une prise en charge de plus en plus conservatrice des formes non compliquées. Cet article résume la prise en charge de la diverticulite aiguë gauche simple, en s'appuyant sur les nouvelles recommandations et en abordant principalement le traitement antibiotique, la prise en charge ambulatoire ou hospitalière et les indications à la coloscopie.