Toward a typeface for the transcription of facial actions in sign languages

International audienceNon-manual actions, and more specifically facial actions (FA) can be found in all Sign Languages (SL). Those actions involve all the different facial parts and can have various and intricate linguistic relations with manual signs. Unlike in vocal languages, FA in SL provide more meaning than simple expressions of feelings and emotions. Yet non-manual parameters are among the most unknown formal features in SL studies. During the past 30 years, some studies have started questioning the meanings and linguistic values and the relations between manual and non-manual signs (Crashborn et al. 2008; Crashborn & Bank 2014); more recently, SL corpora have been analysed, segmented, and transcribed to help study FA (Vogst-Svenden 2008; Bergman et al. 2008; Sutton-Spence & Day 2008).Moreover, to fill the lack of an annotation system for FA, a few manual annotation systems have integrated facial glyphs, such as HamNoSys (Prillwitz et al. 1989) and SignWriting (Sutton 1995). On one hand, HamNoSys has been developed to describe all existing SLs at a phonetic level; it allows a formal, linear, highly detailed and searchable description of manual parameters. As for non-manual parameters, HamNoSys offers the replacement of hands by another articulators. Non-manual parameters can be written as “eyes” or “mouth” and described by the same symbols developed for hands (Hanke 2004). Unfortunately only a limited number of manual symbols can be translated into FA and the annotation system remains incomplete. On the other hand, SignWriting describes SL with iconic symbols placed in a 2D space representing the signer’s body. Facial expressions are divided into mouth, eyes, nose, eyebrows, etc., and are drawn in a circular “head” much like emoticons. SignWriting offers a detailed description of posture and actions of non-manual parameters, but does not ensure compatibility with the most common annotation software used by SL linguists (e.g., ELAN).Typannot, a interdisciplinary project led by linguists, designers, and developers, which aims to set up a complete transcription system for SL that includes every SL parameter (handshape, localisation, movement, FA), has developed a different methodologie. As mentioned earlier, FA have various linguistic values (mouthings, adverbial mouth gestures, semantically empty, enacting, whole face) and also include prosody and emotional meanings. In this regard, they can be more variable and signer-related than manual parameters. To offer the best annotation tool, Typannot’s approach has been to define facial parameters and all their possible tangible configurations. The goal is to set up the most efficient, simple, yet complete and universal formula to describe all possible FA.This formula is based on a 3 dimensional grid. Indeed all the different configurations of FA can be described by its X, Y, Z axis position. As a result, all FA can be described and encoded using a restricted list of 39 qualifiers. Based on this model and to help reduce the annotation process, a set of generic glyphs has been developed. Each qualifier has its own symbolic “generic” glyph. This methodical decomposition of all facial components enables a precise and accurate transcription of a complex FA using only a few glyphs.This formula and its generic glyphs have gone through a series of tests and revisions. Recently, an 18m20s long FA corpus of two deaf signers has been recorded using two different cameras. The first one, RGB HQ, is used to capture a high quality image and the second, infrared Kinect, is used to captured the depth. The latter was linked with Brekel Proface 2 (Leong et al. 2015), a 3D animation software that enables an automatic recognition of FA. This corpus has been fully annotated using Typannot’s generic glyphs. These annotations have enabled the validation of the general structure of Typannot FAformula and to identify some minor corrections to be made. For instance, it has been shown that the description of the air used to puff out or suck in cheeks is too restrictive and the description of the opening and closure of the eyelids is too unnecessarily precise.When those changes are implemented, our next task will be to develop a morphological glyphic system that will combine the different generic glyphs used for each facial parameter into one unique morphological glyph. This means that for any given FA, all the information contained in Typannot descriptive formula will be contained within one legible glyph. Some early research and work has already begun on this topic, but needs further development before providing a statement on its typographic structure. When this system is completed, it will be released with its own virtual keyboard (Typannot Keyboard, currently in development for handshapes) to help transcription and improve annotation processes.Bibliography :-Chételat-Pelé, E. (2010). Les Gestes Non Manuels en Langue des Signes Française ; Annotation, analyse et formalisation : application aux mouvements des sourcils et aux clignements des yeux. Université de Provence - Aix-Marseille I.-Crasborn, O., Van Der Kooij, E., Waters, D., Woll, B., & Mesch, J. (2008). Frequency distribution and spreading behavior of different types of mouth actions in three sign languages. Sign Language & Linguistics, 11(1), 45–67.-Crasborn, O. A., & Bank, R. (2014). An annotation scheme for the linguistic study of mouth actions in sign languages. http://repository.ubn.ru.nl/handle/2066/132960-Fontana, S. (2008). Mouth actions as gesture in sign language. Gesture, 8(1), 104‑123.-Hanke, T. (2004). HamNoSys—Representing sign language data in language resources and language processing contexts. In Workshop on the Representation and Processing of Sign Languages on the occasion of the Fourth International Conference on Language Resources and Evaluation (p. 1‑6).-Leong, C. W., Chen, L., Feng, G., Lee, C. M., & Mulholland, M. (2015). Utilizing depth sensors for analyzing multimodal presentations: Hardware, software and toolkits (p. 547‑556).Presented at Proceedings of the 2015 ACM on International Conference on Multimodal Interaction, ACM.-Prillwitz, S., Leven, R., Zienert, H., Hanke, T., & Henning, J. (1989). Hamburg notation system for sign languages: An introductory guide. Signum Press, Hamburg.-Sandler, W. (2009). Symbiotic symbolization by hand and mouth in sign language. Semiotica, 2009(174), 241‑275. http://doi.org/10.1515/semi.2009.035-Sutton, V. (1995). Lessons in Sign Writing: Textbook. DAC, La Jolla (CA).-Sutton-Spence, R., & Boyes-Braem, P. (2001). The hands are the head of the mouth: The mouth as articulator in sign languages. Signum Press, Hamburg

Involvement of a ventral tegmental area-Amygdala pathway in anxiety and fear

Les troubles mentaux sont la principale cause d'handicap au monde (OMS). Les expériences traumatiques et le stress social favorisent le développement des troubles mentaux tels que les troubles du stress post-traumatique et les troubles anxieux. Le manque de connaissance sur l'étiologie de ces troubles a conduit à ce que les thérapies ciblent les symptômes plutôt que les causes sous-jacentes de ces troubles. Ainsi, un enjeu clinique majeur est de comprendre comment les individus contrôlent leurs émotions et gèrent les situations stressantes.Mon projet de thèse vise à étudier les mécanismes fondamentaux régulant les troubles mentaux où les individus sont submergés par le stress, tel que les désordres de l'anxiété et de la peur. L'ATV est une structure hétérogène connue pour son rôle dans la sensation de plaisir mais aussi pour son implication dans la valence négative où certaines de ses sous-populations neuronales sont activées par des stimuli aversifs. Cette diversité fonctionnelle pourrait être liée aux différentes sous-populations neuronales de l'ATV ainsi qu'à leurs différentes connections afférentes et efférentes. Néanmoins, l'interaction entre l'ATV et les structures régulant les comportementaux défensifs associés à l'anxiété et la peur reste mal compris.L'hypothèse de ma thèse place l'ATV comme un important modulateur de l'activité de l'amygdale pouvant ainsi réguler l'anxiété et la peur. Mon projet est organisé sur l'utilisation d'un modèle de souris d'anxiété et de peur pour répondre à des objectifs distincts mais entrecroisé :-Disséquer les projections glutamatergiques de l'ATV vers l'amygdale ainsi que leur contribution dans l'anxiété adaptative et pathologique-Déterminer les afférences et efférences neuronales de l'ATV régulant la réponse de peur J 'ai complété mon premier objectif par des approches histologiques en cartographiant la distribution des neurones glutamatergiques de l'ATV et leurs innervations de l'amygdale. Ces résultats sont en accord avec une accumulation de preuves indiquant que l'ATV est une structure composée de populations neuronales compartimentalisées selon leurs fonctions.A l'aide de techniques d'électrophysiologie et du modèle de défaite sociale chronique (DSC) afin d'induire des troubles anxieux de longue durée, nous avons trouvé des altérations de la plasticité pré- et post-synaptique suggérant une potentialisation de la transmission neuronale glutamatergique entre l'ATV et l'amygdale suite à un DSC. Par la suite, j'ai induit une activation chronique des projections glutamatergique de l'ATV allant à l'amygdale via des techniques d'optogénétiques in vivo. Cette modulation est suffisante pour augmenter l'anxiété et causer des changements de plasticité synaptique similaires à ceux retrouvés durant le DSC. Ainsi, cet axe de ma thèse suggère fortement un rôle de cette projections neuronale dans l'induction des troubles anxieux.Mon second objectif est basé sur la découverte d'une régulation de la peur par des efférences du tegmentum latérodorsal allant à l'ATV. J'ai étudié ici la connectivité de l'ATV avec plusieurs centres de la peur où j'ai déterminé le type cellulaire et les connections responsables de cette régulation. Une modulation des projections de l'ATV allant à l'amygdale a été suffisantes pour altérer l'induction contextuelle de la peur. De plus, l'inhibition des projections GABAergiques de l'ATV vers l'amygdale ont réduit la réponse contextuelle de peur. Ainsi, le second axe de ma thèse a révélé le rôle des neurones GABAergiques de l'ATV projetant à l'amygdale dans l'induction de la peur.En conclusion, mes travaux mettent en évidence la connectivité entre deux centres cérébraux de la saillance émotionnelle, l'ATV et l'amygdale. De plus, mon étude suggère que les effets du stress sur ces connections pourrait contribuer aux troubles anxieux. De future thérapies pourraient cibler le réseau neuronal ATV-Amygdale afin de soulager les symptômes des troubles anxieux.Mental disorders are the leading cause of disability-adjusted life years worldwide. Traumatic experiences and social stress promote the onset of mental disorders including post-traumatic stress disorders (PTSD) and anxiety disorders. A lack of understanding in the etiology of these disorders have led current therapies to aim at treating symptoms rather than the underlying dysfunctions. Hence, a major clinical challenge is to unravel how individuals control their emotions and cope with stressful events. My PhD project addresses the fundamental mechanisms that underpin mental disorders where individuals cannot cope with stressful events leading to excessive fear and anxiety. While the ventral tegmental area (VTA) is a heterogeneous brain structure well-studied for its function in reward processing, this brain region also plays a role in signaling negative valence. Indeed, subpopulations of VTA neurons respond to aversive stimuli. This functional divergence could arise from the unique properties in distinct target-specific cell populations within the VTA. However, our understanding of the inputs and outputs of the VTA that could contribute to the onset of exacerbated anxiety and fear responses is currently very limited.The central hypothesis of my PhD project is that VTA projection neurons are significant modulators of the main center of anxiety and fear: the amygdala. My project is designed to model and study these defensive behaviors in mice. Hence, my thesis addresses two distinct but overlapping aims:(i) Dissecting VTA glutamatergic projections to the amygdala and their contribution to adaptative and pathological anxiety.(ii) Assessing the inputs and outputs of VTA projection neurons regulating fear responses.For my first aim, I studied the distribution pattern of VTA glutamatergic neurons and their axonal innervation of the amygdala through histological studies. My results are consistent with a growing body of evidence depicting the VTA as a structure comprised of well-compartmentalized cell populations with different functional roles. Secondly, relying upon electrophysiological tools and the use of the chronic social defeat (CSD) paradigm to induce anxiety disorders, I found alterations of both presynaptic and post-synaptic plasticity in VTA glutamatergic neurons projecting to the amygdala. This suggests a potentiation of the neuronal transmission for these efferences to the amygdala paralleled with the appearance of anxiety following CSD. Causality was shown using optogenetic tools to chronically activate these projecting neurons. Indeed, this modulation was sufficient to increase anxiety levels and induce similar change in synaptic plasticity as in CSD. Hence, this first aim strongly suggests a role of this neuronal projection in anxiety disorders.My second aim was based upon the discovery that the laterodorsal tegmentum contribute to fear responses, namely freezing, through efferences to the VTA. I focused on unravelling the connectivity of the VTA with fear centers, and dissecting the contribution of individual cell-types to this newly discovered role. Using chemogenetic tools, I showed that activation of VTA-amygdala pathway is necessary for the manifestation of unconditionned freezing upon electric foot shock exposure. In contrast to my first aim, I showed in this second axis that VTA GABAergic projecting neurons to the amygdala, but not glutamatergic neither dopaminergic cells, are responsible for this fear response.Overall, my thesis work brings new insights into the interconnectivity of two salience centers in the brain, namely the VTA and the amygdala. Moreover, my results suggest that stress challenges on this brain connections contribute to maladaptive anxiety. I propose that future circuit-based therapies could be targeted at the VTA-amygdala pathway to alleviates anxiety symptoms

Implication d'une voie neuronale allant de l'aire tegmentale ventrale à l'amygdale dans l'anxiété et la peur

Mental disorders are the leading cause of disability-adjusted life years worldwide. Traumatic experiences and social stress promote the onset of mental disorders including post-traumatic stress disorders (PTSD) and anxiety disorders. A lack of understanding in the etiology of these disorders have led current therapies to aim at treating symptoms rather than the underlying dysfunctions. Hence, a major clinical challenge is to unravel how individuals control their emotions and cope with stressful events. My PhD project addresses the fundamental mechanisms that underpin mental disorders where individuals cannot cope with stressful events leading to excessive fear and anxiety. While the ventral tegmental area (VTA) is a heterogeneous brain structure well-studied for its function in reward processing, this brain region also plays a role in signaling negative valence. Indeed, subpopulations of VTA neurons respond to aversive stimuli. This functional divergence could arise from the unique properties in distinct target-specific cell populations within the VTA. However, our understanding of the inputs and outputs of the VTA that could contribute to the onset of exacerbated anxiety and fear responses is currently very limited.The central hypothesis of my PhD project is that VTA projection neurons are significant modulators of the main center of anxiety and fear: the amygdala. My project is designed to model and study these defensive behaviors in mice. Hence, my thesis addresses two distinct but overlapping aims:(i) Dissecting VTA glutamatergic projections to the amygdala and their contribution to adaptative and pathological anxiety.(ii) Assessing the inputs and outputs of VTA projection neurons regulating fear responses.For my first aim, I studied the distribution pattern of VTA glutamatergic neurons and their axonal innervation of the amygdala through histological studies. My results are consistent with a growing body of evidence depicting the VTA as a structure comprised of well-compartmentalized cell populations with different functional roles. Secondly, relying upon electrophysiological tools and the use of the chronic social defeat (CSD) paradigm to induce anxiety disorders, I found alterations of both presynaptic and post-synaptic plasticity in VTA glutamatergic neurons projecting to the amygdala. This suggests a potentiation of the neuronal transmission for these efferences to the amygdala paralleled with the appearance of anxiety following CSD. Causality was shown using optogenetic tools to chronically activate these projecting neurons. Indeed, this modulation was sufficient to increase anxiety levels and induce similar change in synaptic plasticity as in CSD. Hence, this first aim strongly suggests a role of this neuronal projection in anxiety disorders.My second aim was based upon the discovery that the laterodorsal tegmentum contribute to fear responses, namely freezing, through efferences to the VTA. I focused on unravelling the connectivity of the VTA with fear centers, and dissecting the contribution of individual cell-types to this newly discovered role. Using chemogenetic tools, I showed that activation of VTA-amygdala pathway is necessary for the manifestation of unconditionned freezing upon electric foot shock exposure. In contrast to my first aim, I showed in this second axis that VTA GABAergic projecting neurons to the amygdala, but not glutamatergic neither dopaminergic cells, are responsible for this fear response.Overall, my thesis work brings new insights into the interconnectivity of two salience centers in the brain, namely the VTA and the amygdala. Moreover, my results suggest that stress challenges on this brain connections contribute to maladaptive anxiety. I propose that future circuit-based therapies could be targeted at the VTA-amygdala pathway to alleviates anxiety symptoms.Les troubles mentaux sont la principale cause d'handicap au monde (OMS). Les expériences traumatiques et le stress social favorisent le développement des troubles mentaux tels que les troubles du stress post-traumatique et les troubles anxieux. Le manque de connaissance sur l'étiologie de ces troubles a conduit à ce que les thérapies ciblent les symptômes plutôt que les causes sous-jacentes de ces troubles. Ainsi, un enjeu clinique majeur est de comprendre comment les individus contrôlent leurs émotions et gèrent les situations stressantes.Mon projet de thèse vise à étudier les mécanismes fondamentaux régulant les troubles mentaux où les individus sont submergés par le stress, tel que les désordres de l'anxiété et de la peur. L'ATV est une structure hétérogène connue pour son rôle dans la sensation de plaisir mais aussi pour son implication dans la valence négative où certaines de ses sous-populations neuronales sont activées par des stimuli aversifs. Cette diversité fonctionnelle pourrait être liée aux différentes sous-populations neuronales de l'ATV ainsi qu'à leurs différentes connections afférentes et efférentes. Néanmoins, l'interaction entre l'ATV et les structures régulant les comportementaux défensifs associés à l'anxiété et la peur reste mal compris.L'hypothèse de ma thèse place l'ATV comme un important modulateur de l'activité de l'amygdale pouvant ainsi réguler l'anxiété et la peur. Mon projet est organisé sur l'utilisation d'un modèle de souris d'anxiété et de peur pour répondre à des objectifs distincts mais entrecroisé :-Disséquer les projections glutamatergiques de l'ATV vers l'amygdale ainsi que leur contribution dans l'anxiété adaptative et pathologique-Déterminer les afférences et efférences neuronales de l'ATV régulant la réponse de peur J 'ai complété mon premier objectif par des approches histologiques en cartographiant la distribution des neurones glutamatergiques de l'ATV et leurs innervations de l'amygdale. Ces résultats sont en accord avec une accumulation de preuves indiquant que l'ATV est une structure composée de populations neuronales compartimentalisées selon leurs fonctions.A l'aide de techniques d'électrophysiologie et du modèle de défaite sociale chronique (DSC) afin d'induire des troubles anxieux de longue durée, nous avons trouvé des altérations de la plasticité pré- et post-synaptique suggérant une potentialisation de la transmission neuronale glutamatergique entre l'ATV et l'amygdale suite à un DSC. Par la suite, j'ai induit une activation chronique des projections glutamatergique de l'ATV allant à l'amygdale via des techniques d'optogénétiques in vivo. Cette modulation est suffisante pour augmenter l'anxiété et causer des changements de plasticité synaptique similaires à ceux retrouvés durant le DSC. Ainsi, cet axe de ma thèse suggère fortement un rôle de cette projections neuronale dans l'induction des troubles anxieux.Mon second objectif est basé sur la découverte d'une régulation de la peur par des efférences du tegmentum latérodorsal allant à l'ATV. J'ai étudié ici la connectivité de l'ATV avec plusieurs centres de la peur où j'ai déterminé le type cellulaire et les connections responsables de cette régulation. Une modulation des projections de l'ATV allant à l'amygdale a été suffisantes pour altérer l'induction contextuelle de la peur. De plus, l'inhibition des projections GABAergiques de l'ATV vers l'amygdale ont réduit la réponse contextuelle de peur. Ainsi, le second axe de ma thèse a révélé le rôle des neurones GABAergiques de l'ATV projetant à l'amygdale dans l'induction de la peur.En conclusion, mes travaux mettent en évidence la connectivité entre deux centres cérébraux de la saillance émotionnelle, l'ATV et l'amygdale. De plus, mon étude suggère que les effets du stress sur ces connections pourrait contribuer aux troubles anxieux. De future thérapies pourraient cibler le réseau neuronal ATV-Amygdale afin de soulager les symptômes des troubles anxieux

Hyperactive and anxiolytic‐like behaviors result from loss of COUP‐TFI/Nr2f1 in the mouse cortex

International audienceThe nuclear receptor COUP TFI (also known as Nr2f1) plays major roles in specifying distinct neuronal subtypes during patterning of the neocortical motor and somatosensory cortex, as well as in regulating the longitudinal growth of the hippocampus during development. In humans, mutations in the NR2F1 gene lead to a global developmental delay and intellectual disabilities. While more than 30% of patients show behavioral features of autism spectrum disorder, 16% of haploinsufficient children show signs of hyperactivity and impulsivity. Loss of COUP-TFI in the cortical mouse primordium results in altered area organization and serotonin distribution, abnormal coordination of voluntary movements and learning and memory deficits. Here, we asked whether absence of COUP-TFI affects locomotor activity, anxiety, as well as depression. Mice mutant for COUP-TFI have normal motor coordination, but significant traits of hyperactivity, which does not seem to respond to N-Methyl-D-aspartate (NMDA) antagonists. However, no changes in anxiety, despite increased locomotor performances, were observed in the open field task. On the contrary, elevated plus maze and dark-light test explorations indicate a decreased anxiety-like behavior in COUP-TFI mutant mice. Finally, significantly reduced immobility in the forced swim test and no changes in anhedonia in the sucrose preference task suggest no particular depressive behaviors in mutant mice. Taken together, our study shows that loss of COUP-TFI leads to increased locomotor activity but less anxiety and contributes in further deciphering the pathophysiology of patients haploinsufficient for NR2F1

Dopamine and glutamate receptors control social stress-induced striatal ERK1/2 activation

International audienceStress has been acknowledged as one of the main risk factors for the onset of psychiatric disorders. Social stress is the most common type of stressor encountered in our daily lives. Uncovering the molecular determinants of the effect of stress on the brain would help understanding the complex maladaptations that contribute to pathological stress-related mental states. We examined molecular changes in the reward system following social defeat stress in mice, as increasing evidence implicates this system in sensing stressful stimuli. Following acute or chronic social defeat stress, the activation (i.e. phosphorylation) of extracellular signal-regulated kinases ERK1 and ERK2 (pERK1/2), markers of synaptic plasticity, was monitored in sub-regions of the reward system. We employed pharmacological antagonists and inhibitory DREADD to dissect the sequence of events controlling pERK1/2 dynamics. The nucleus accumbens (NAc) showed marked increases in pERK1/2 following both acute and chronic social stress compared to the dorsal striatum. Increases in pERK1/2 required dopamine D1 receptors and GluN2B-containing NMDA receptors. Paraventricular thalamic glutamatergic inputs to the NAc are required for social stress-induced pERK1/2. The molecular adaptations identified here could contribute to the long-lasting impact of stress on the brain and may be targeted to counteract stress-related psychopathologies

Guida all'annotazione per il font Typannot, nell'ambito del progetto Typannot-Graphé

rapporto R01The sign language transcription system "Typannot" is developed by the GestualScript research team. Its purpose is to transcribe the form of all sign languages in the world, taking care for all parameters. The requirement of transcription leads to consider that one must therefore develop a font by parameter. The foundations and characteristics of Typannot fonts are presented first in a deliberately practical manner in order to meet the operational requirements, which are covered by an annotation guide; the insertion and the use of these fonts in the ELAN software, main place used for the transcription of LS, are shown subsequently. This annotation guide was created during a specific state of development of Typannot fonts, and it is obviously going to evolve according to advanced fonts and the virtual keyboard; therefore, the guide will be updated regularly.Le système de transcription des langues des signes Typannot est développé par l’équipe de recherche GestualScript. Il a pour vocation de transcrire la forme de l’ensemble des langues des signes dans le monde pour tous ses paramètres. L’exigence de la transcription amène à considérer qu’on doit élaborer donc une police de caractère par paramètre. Dans un premier temps, les fondements et les caractéristiques des polices Typannot sont présentés de manière volontairement pratique afin de répondre aux exigences opératoires qui relève d’un guide d’annotation. Puis, dans un deuxième temps, on montre l’insertion et l’utilisation de ces polices de caractères dans le logiciel ELAN, principal lieu utilisés pour la transcription des LS. Ce guide d’annotation a été constitué lors d’un état particulier de développement des polices de caractères Typannot, et il est évidemment amené à évoluer en fonction des avancés des polices de caractère et du clavier virtuel; le guide sera donc mis à jour régulièrement.Il sistema di trascrizione della lingua dei segni Typannot viene sviluppato dal team di ricerca GestualScript. Il suo scopo è trascrivere la forma di tutte le lingue dei segni nel mondo per tutti i parametri. Il requisito della trascrizione porta a considerare che bisogna quindi sviluppare una font di caratteri per parametro. Inizialmente, le basi e le caratteristiche dei caratteri Typannot sono presentate in modo deliberatamente pratico per soddisfare i requisiti operativi che rientrano in una guida all'annotazione. Quindi, in una seconda fase, viene mostrato l'inserimento e l'uso di questi caratteri nel software ELAN, principale sito utilizzato per la trascrizione di LS. Questa guida all'annotazione è stata creata durante un momento puntuale di sviluppo dei font Typannot e si evolverà ovviamente in base agli avanzamenti dei caratteri e della tastiera virtuale; la guida sarà quindi aggiornata regolarmente

A non-canonical GABAergic pathway to the VTA promotes unconditioned freezing

International audienceAbstract Freezing is a conserved defensive behaviour that constitutes a major stress-coping mechanism. Decades of research have demonstrated a role of the amygdala, periaqueductal grey and hypothalamus as core actuators of the control of fear responses, including freezing. However, the role that other modulatory sites provide to this hardwired scaffold is not known. Here, we show that freezing elicited by exposure to electrical foot shocks activates laterodorsal tegmentum (LDTg) GABAergic neurons projecting to the VTA, without altering the excitability of cholinergic and glutamatergic LDTg neurons. Selective chemogenetic silencing of this inhibitory projection, but not other LDTg neuronal subtypes, dampens freezing responses but does not prevent the formation of conditioned fear memories. Conversely, optogenetic-activation of LDTg GABA terminals within the VTA drives freezing responses and elicits bradycardia, a common hallmark of freezing. Notably, this aversive information is subsequently conveyed from the VTA to the amygdala via a discrete GABAergic pathway. Hence, we unveiled a circuit mechanism linking LDTg-VTA-amygdala regions, which holds potential translational relevance for pathological freezing states such as post-traumatic stress disorders, panic attacks and social phobias

Il corpo tra senso e forma: analisi kinesiologica e rappresentazione tipografica del movimento in Lingua dei Segni

International audienceMost of the research on Sign Languages (SLs) and gesture is characterized by a focus on hands, considered the sole parts responsible for the creation of meaning. The corporal part of signs and gestures is then blurred by hand dominance. This particularly impacts the linguistic analysis of movement, which is described as unstable, even idiosyncratic. Boutet's Kinesiological Approach (KinApp) repositions the speaker's body at the core of meaning emergence: how this approach considers and conceptualizes movement is the subject of this article. First, the reasons that led SLs researchers to neglect the analysis of the sign signifying form, focusing on the hand, are exposed. The following part introduces KinApp which, thru a radical change of point of view, allows to reveal the movement simplicity and stability: understanding the cognitive and motor reasons for this stability are the subject of research whose methodology is described. Setting the body at the center of analysis requires a descriptive model capable of accounting for the SLs signifying form, thus going beyond existing transcription systems. The last part is devoted to the presentation of Typannot, a new transcription system, aimed not only at a kinesiological description of SLs but also at assisting researchers to modify their way to understand and analyze movement.La plupart des recherches sur les Langues des Signes (LS) et la gestualité sont caractérisées par une focalisation sur les mains, considérées les seules responsables de la création du sens. La nature corporelle des signes et des gestes est alors cachée par leur apparence manuelle. Ceci impacte particulièrement l’analyse linguistique du mouvement, qui est décrit comme instable, voire idiosyncratique. L’Approche Kinésiologique (KinApp) de Boutet remet au cœur de l’émergence du sens le corps du locuteur. La manière dont cette approche appréhende et conceptualise le mouvement est l’objet de cet article. En premier lieu, seront présentées les raisons ayant conduit les chercheurs de LS à mettre de côté l’analyse de la forme signifiante des signes et à se focaliser sur les mains. Ensuite, sera présentée la KinApp qui, à travers un changement radical de point de vue, permet de révéler la simplicité et la stabilité du mouvement. La compréhension des raisons cognitives et motrices de cette stabilité sont l’objet d’une recherche dont la méthodologie sera explicitée ici. Mettre le corps au centre de l’analyse nécessite d’un modèle descriptif capable de rendre compte de la forme signifiante des LS, dépassant ainsi les limites des systèmes de transcription existants. La dernière partie de l’article sera consacrée à la présentation de Typannot, un nouveau système de transcription, dont le but n’est pas seulement de permettre une description kinésiologique de la LS, mais aussi d’aider les chercheurs à modifier leur façon d’appréhender et d’analyser le mouvement.La maggior parte della ricerca sulle Lingue dei Segni (LS) e sulla gestualità è focalizzata sulle mani, considerate le uniche responsabili della creazione di significato. La natura corporea di segni e gesti è quindi nascosta dalla loro componente manuale: ciò ha un notevole impatto sull'analisi linguistica del movimento, che è descritto come instabile, persino idiosincratico. L'Approccio Kinesiologico di Boutet (KinApp) riporta il corpo di chi parla al centro dell'emergere del significato; il modo in cui questo approccio vede e concettualizza il movimento è l'argomento di questo articolo. Per prima cosa vengono presentate le ragioni che hanno portato i ricercatori di LS a mettere da parte l'analisi della forma significante dei segni e a concentrarsi sulle mani. Successivamente, viene presentata la KinApp che, tramite un radicale cambio di punto di vista, rivela la semplicità e la stabilità del movimento. La comprensione delle ragioni cognitive e motorie di questa stabilità è ad oggi oggetto di ricerca, di cui si spiega la metodologia. Mettere il corpo al centro dell'analisi richiede un modello descrittivo in grado di rendere conto della forma significante, ben oltre i limiti dei sistemi di trascrizione esistenti: l'ultima parte è quindi dedicata alla presentazione di Typannot, un nuovo sistema di trascrizione, il cui scopo non è solo quello di consentire una descrizione kinesiologica delle LS, ma anche di aiutare i ricercatori a modificare il modo di farlo capire ed analizzare il movimento

Trascrivere le lingue dei segni con Typannot, un sistema tipografico con più strati di informazione

International audienceThere are more than 140 sign languages (SLs) in the world and studying them is a relatively recent field of research (starting in the 1960s). Linguists have the need to represent the different levels of gestures that make up the signs in order to analyze the way SLs work. Such transcription requires the use of a dedicated graphic system (Slobin et al. 2001). TYPANNOT, the transcription system presented in this article, is a typographic system that allows the description of all formal features of SLs. Our contribution to the field of grapholinguistics is a phonological model and a transcription system for SLs that are rooted in the articulatory possibilities of the signer's body. Compared to existing graphematic systems, our approach of SLs description is both phonological, allowing descriptions of the different articulatory structures (low level) involved in SLs, and logographical, allowing users to read the transcriptions from a unified perspective (high level). We will detail the design principles that drive the development of such a typographic system, the graphemic model that derives from linguistic study, and the tools that allow researchers to use TYPANNOT to its fullest capacities. This article also outlines the kinesiological approach (Boutet, 2018), which TYPANNOT uses, noting radical changes in the way researchers should look at meaning through gesture. This approach opens new perspectives in researching movement itself as a central source of meaning in human communication via gesture.Il existe plus de 140 langues des signes (LS) dans le monde et leur étude est un domaine de recherche relativement récent. Les linguistes ont besoin de représenter les différents niveaux de gestes qui composent les signes afin d'analyser le fonctionnement des LS. Une telle transcription nécessite l'utilisation d'un système graphique dédié. Typannot, le système de transcription présenté dans cet article, est un système typographique qui permet la description de toutes les fonctionnalités formelles des LS: la contribution au domaine de la grapholinguistique est un modèle phonologique et un système de transcription pour les LS, les deux enracinés dans les possibilités articulatoires du corps du signeur. Par rapport aux systèmes graphématiques existants, l'approche à la description des LS est à la fois phonologique - permettant des descriptions des différentes structures articulatoires (de bas niveau) impliquées dans les LS -, et logographique - permettant de lire les transcriptions dans une perspective unifiée (de haut niveau). On détaille les principes de conception qui mènent au développement d'un tel système typographique, le modèle graphémique issu de l'étude linguistique et les outils qui permettent aux chercheurs d'utiliser Typannot à son maximum. Cet article décrit également l'approche kinésiologique que Typannot utilise, notant des changements radicaux dans la façon dont les chercheurs devraient étudier le sens par le geste. Cette approche ouvre de nouvelles perspectives dans la recherche du mouvement, lui-même considéré comme source centrale de sens dans la communication gestuelle.Nel mondo esistono più di 140 lingue dei segni (LS), e studiarle è un campo di ricerca relativamente recente. I linguisti hanno la necessità di rappresentare i diversi livelli di gestualità che compongono i segni al fine di analizzare il modo in cui funzionano le LS. Tale trascrizione richiede l'utilizzo di un sistema grafico dedicato. Typannot, il sistema di trascrizione presentato in questo articolo, è un sistema tipografico che consente di descrivere tutte le caratteristiche formali delle LS: il contributo al campo della grafolinguistica è un modello fonologico e un sistema di trascrizione per LS, ambedue radicati nelle possibilità articolatorie del corpo del segnante. Rispetto ai sistemi grafematici esistenti, l'approccio alla descrizione delle LS è sia fonologico – descrivendo le strutture articolatorie (basso livello) coinvolte negli SL -, sia logografico - consentendo di leggere le trascrizioni in una prospettiva unificata (alto livello). Vengono di seguito descritti i principi progettuali che guidano lo sviluppo di Typannot, il modello grafico derivato dallo studio linguistico ed infine gli strumenti che consentono ai ricercatori il pieno utilizzo di Typannot. Questo articolo delinea anche l'approccio kinesiologico utilizzato in Typannot, che palesa la necessità di cambiamenti radicali nello studio dei significati attraverso i gesti. Questo approccio apre nuove prospettive nella ricerca sulla comunicazione gestuale, ponendo il movimento stesso come fonte centrale di significato