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International audience; Disinhibition, mainly caused by damage in frontotemporal brain regions, is one of the major causes of caregiver distress in neurodegenerative dementias. Behavioural inhibition deficits are usually described as a loss of social conduct and impulsivity, whereas cognitive inhibition deficits refer to impairments in the suppression of prepotent verbal responses and resistance to distractor interference. In this review, we aim to discuss inhibition deficits in neurodegenerative dementias through behavioural, cognitive, neuroanatomical and neurophysiological exploration. We also discuss impulsivity and compulsivity behaviours as related to disinhibition. We will therefore describe different tests available to assess both behavioural and cognitive disinhibition and summarise different manifestations of disinhibition across several neurodegenerative diseases (behavioural variant of frontotemporal dementia, Alzheimer's disease, Parkinson's disease, progressive supranuclear palsy, Huntington's disease). Finally, we will present the latest findings about structural, metabolic, functional, neurophysiological and also neuropathological correlates of inhibition impairments. We will briefly conclude by mentioning some of the latest pharmacological and non pharmacological treatment options available for disinhibition. Within this framework, we aim to highlight i) the current interests and limits of tests and questionnaires available to assess behavioural and cognitive inhibition in clinical practice and in clinical research; ii) the interpretation of impulsivity and compulsivity within the spectrum of inhibition deficits; and iii) the brain regions and networks involved in such behaviours.

International audience; Apathy, a common neuropsychiatric symptom associated with dementia, has a strong impact on patients’ and caregivers’ quality of life. However, it is still poorly understood and hard to define. The main objective of the ECOCAPTURE programme is to define a behavioural signature of apathy using an ecological approach. Within this program, ECOCAPTURE@HOME is an observational study which aims to validate a method based on new technologies for the remote monitoring of apathy in real life. For this study, we plan to recruit 60 couples: 20 patient-caregiver dyads in which patients suffer from behavioral variant Fronto-Temporal Dementia, 20 patient-caregiver dyads in which patients suffer from Alzheimer Disease and 20 healthy control couples. These dyads will be followed for 28 consecutive days via multi-sensor bracelets collecting passive data (acceleration, electrodermal activity, blood volume pulse). Active data will also be collected by questionnaires on a smartphone application. Using a pool of metrics extracted from these passive and active data, we will validate a measurement model for three behavioural markers of apathy (i.e., daytime activity, quality of sleep, and emotional arousal). The final purpose is to facilitate the follow-up and precise diagnosis of apathy, towards a personalised treatment of this condition within everyday life.

International audience; Introduction: We aimed to investigate phenotypic heterogeneity in the behavioral variant of frontotemporal dementia (bvFTD) through assessment of inhibition deficits.Methods: We assessed occurrences of 16 behavioral inhibition deficits from video recordings of 15 bvFTD patients (early stage) and 15 healthy controls (HC) in an ecological setting. We extracted dimensions of inhibition deficit and analyzed their correlations with cognitive and clinical measures. Using these dimensions, we isolated patient clusters whose atrophy patterns were explored.Results: After identifying two patterns of inhibition deficit (compulsive automatic behaviors and socially unconventional behaviors), we isolated three behavioral clusters with distinct atrophy patterns. BvFTD-G0 (N = 3), an outlier group, showed severe behavioral disturbances and more severe ventromedial prefrontal cortex/orbitofrontal cortex atrophy. Compared to bvFTD-G1 (N = 6), bvFTD-G2 (N = 6) presented higher anxiety and depression along with less diffuse atrophy especially in midline regions.Discussion: Identifying clinico-anatomical profiles through behavior observation could help to stratify bvFTD patients for adapted treatments.

WOS:000393629800002; International audience; Rothbart's model of temperament, defined as individual differences in reactivity and self-regulation, has a strong heuristic value with applications in a wide variety of children's outcomes. Our objective was to test Rothbart's model applied to children's food behaviours and BMI outcome through behavioural measures. Our hypotheses, according to Rothbart's model, were as follows: (i) self-regulation in eating modulates appetite reactivity; (ii) appetite reactivity increases the risk of excess BMI, whereas self regulation in eating limits this risk. One hundred and four children aged between 7 and 12 years completed four behavioural tasks to assess scores for two components of appetite reactivity (i.e. appetite arousal and appetite persistence) and two components of self-regulation in eating (i.e. self-regulation in eating without hunger and self-regulation in eating speed). Their heights and weights were measured in order to calculate their BMI-for-age. T-tests and regression analysis were used to verify our hypotheses. None of the scores of self-regulation in eating was directly associated with BMI but we observed a significant impact of self-regulation in eating without hunger on appetite arousal (p-value = 0.04), together with a modest but significant association between appetite persistence and BMI (p value = 0.02). We can thus conclude that our behavioural measures could be used for the determination of the child's eating temperament. Further studies are needed to investigate how to use these measures to improve the treatment of overweight in children. (C) 2016 Elsevier Ltd. All rights reserved.

International audience; Background/Objective: Appetitive traits and general temperament traits have both been correlated with adiposity and obesity in children. However, very few studies have tested structural models to identify the links between temperament, appetitive traits and adiposity in children. A validated structural model would help suggesting mechanisms to explain the impact of temperament on body mass index (BMI). In this study, we used Rothbart's heuristic definition of temperament as a starting point to define four appetitive traits, including two appetite reactivity dimensions (Appetite Arousal and Appetite Persistence) and two dimensions of self-regulation in eating (Self-regulation In Eating Without Hunger and Self-regulation in Eating Speed). We conducted a cross-sectional study in young adolescents to validate a structural model including these four appetitive traits, Effortful Control (a general temperament trait) and adiposity. Subjects/Methods: A questionnaire assessing the four appetitive trait dimensions and Effortful Control was completed by adolescents from 10 to 14 years old (n=475), and their BMI-for-age was calculated (n=441). In total, 74% of the study participants were normal weight, 26% were overweight and 8% were obese. We then used structural equation modelling to test the structural model. Results: We identified a well-fitting structural model (Comparative Fit Index=0.91; Root Mean Square Error of Approximation=0.04) that supports the hypothesis that Effortful Control impacts both dimensions of self-regulation in eating, which in turn are linked with both appetite reactivity dimensions. Moreover, Appetite Persistence is the only appetitive trait that was significantly related to adiposity (B=0.12; Ptextless0.05). Conclusions: Our model shows that Effortful Control is related to adiposity through the mediation of an individual's `eating temperament' (appetite reactivity and self-regulation in eating). Results suggest that young adolescents who exhibit high appetite reactivity but a low level of self-regulation in eating are at higher risk for excess adiposity.

International audience; Selon le modèle de Rothbart [1], le tempérament est défini, d'une part, par le niveau de réactivité des enfants, et d'autre part, par leur capacité d'autorégulation. Au moyen de deux études, nous avons cherché a testé la valeur de ce modèle tempéramental dans le domaine alimentaire enfantin. La première étude [2] est relative à la question du surpoids. Nous avons émis l'hypothèse que les enfants les plus à risque de surpoids étaient les enfants les plus réactifs à la nourriture et s'autorégulant le moins bien. À partir des réponses de 475~pré-adolescents ayant rempli un questionnaire ad hoc et dont on a mesuré l'IMC, l'hypothèse a été confirmée, mais de façon directe pour une des dimensions seulement. La seconde étude [3] concerne la problématique de la néophobie alimentaire, à savoir la réticence à goûter les aliments inconnus qui conduit à une faible consommation de fruits et légumes notamment. Notre hypothèse était que les enfants ayant de faibles capacités à autoréguler leurs émotions consommeraient moins d'un aliment inconnu que des enfants s'autorégulant facilement, et ceci d'autant plus que la consigne de la consommation était incitative plutôt que directive (selon le concept de Goodness of fit suggéré par Thomas et Chess [4]). Quatre-vingt-dix-huit enfants, âgés entre 2~et 3 ans ont participé à une étude expérimentale les amenant à goûter à 5~occasions un aliment inconnu dans un contexte soit incitatif soit directif. Les résultats du post-test ont indiqué que la consommation de l'aliment était supérieure chez les enfants s'autorégulant facilement dans le contexte incitatif, que chez les enfants s'autorégulant difficilement dans le contexte directif. Il apparaît ainsi que le concept de tempérament selon Rothbart, et notamment à travers les capacités d'autorégulation, joue un rôle dans les conduites alimentaires de l'enfant dans leur dimension quantitative (quantités consommées et du surpoids) et qualitative (néophobie et variété du répertoire de consommation).