Cardiorespiratory responses during affective picture viewing: metabolic and attentional aspects

Several lines of research point to a hierarchical structure of emotion with the affective dimensions of valence (degree of pleasantness) and arousal (degree of activation) as strategic determinants of emotion. Pictures, for their ecological validity, have been widely used to evoke and investigate affective reactions in the laboratory and they were adopted in this study. Reactions of most individuals to positive and negative arousing images activate phylogenetically primitive motivational systems. Several somato-physiological measures covary to a certain degree with self-reported valence and arousal evaluations. The goals of this study were multifold: • to replicate previous findings concerning the relationships between breathing variables and self-rated valence and arousal to assess to which extent changes in ventilation are in equilibrium with metabolic activity to determine the level of visual attention involvement during picture viewing to extend our knowledge about autonomic responding by measuring blood pressure (a rather neglected parameter in emotion research). Thirteen picture series, each one of a different content (e.g., erotic couples, nature scenes, mutilated bodies, household objects), were shown to 41 subjects (20 men, 21 women, aged 18-38 years), while breathing parameters (i.e., inspiratory time, expiratory time, inspiratory volume, flow parameters, thoraco-abdominal balance), end-tidal pCO2, heart rate, blood pressure, skin conductance, spontaneous eye-blink rate and affective judgments were recorded. Series consisted of ten pictures of 6-s duration each. Mixed effects regression models were used to assess the relationships between affective judgments and physiological measures. The models tested included a random intercept for each subject and fixed effects for valence, arousal and the interaction term. Sex effects were also tested. More negative valence ratings were associated with larger heart rate deceleration, lower eye-blink rate, and lower end-tidal pCO2. Sustained heart rate deceleration and blink rate inhibition are indicative of increased attention to aversive stimuli and lower pCO2 contributes to heightened sensory perception. We interpret these relationships in terms of an attention bias towards negative stimuli. With increasing arousal, minute ventilation, inspiratory volume, skin conductance and blood pressure increased. These relationships suggest increased energy mobilization in response to both positive and negative arousing stimuli and confirm that breathing parameters are more consistently related to arousal than valence. The ventilatory changes along the arousal dimension are in balance with metabolic activity. Importantly, the arousal effect for blood pressure was limited to the male subjects indicating a sex difference in the reactivity to high-arousal events on this specific parameter. An important, yet not exhaustively answered question is how and to what extent physiological reactions to affective challenges influence human well-being. To be able to address this question we first need to refine our understanding of the physiological, cognitive and behavioral emotion systems. By investigating a broad range of psychophysiological responses to affective pictures from a two-dimensional perspective of emotion, this study enriches our knowledge about the connection between the subjective realm of the emotions and their neurophysiological substrate

Caractérisation expérimentale de métamatériaux en utilisant une ligne triplaque à hauteur variable

National audienceNous présentons une méthode de caractérisation expérimentale des propriétés électromagnétiques des métamatériaux dans la bande (1-6 GHz). Cette technique se base sur la mesure des paramètres de répartition d'une ligne triplaque à hauteur variable permettant ainsi de caractériser des métamatériaux dont le nombre de cellules peut varier suivant plusieurs directions. Cette possibilité d'augmenter le nombre de cellules est nécessaire pour l'étude de la réponse asymptotique des métamatériaux. Nous présentons la cellule de mesure, la procédure expérimentale et les premiers résultats expérimentaux

The down-regulation of disgust by implementation intentions: experiential and physiological concomitants

Emotion regulation plays a key role in mental health and psychopathology. Therefore, it seems important to develop effective forms of emotion regulation. Implementation intentions are if-then plans that help people attain their self-regulatory goals. Perspective-taking and response-focused implementation intentions have been shown to reduce feelings of unpleasantness and arousal, respectively, in response to briefly presented disgusting pictures. The present study addressed the open research questions whether forming these types of implementation intentions is effective in regulating affect during prolonged presentation of disgusting pictures, and whether it is associated with changes in physiological arousal. Eighty-one participants viewed disgusting, neutral, and pleasant pictures of 6 s duration under four instructions: the goal intention to not get disgusted, this goal intention furnished with a perspective-taking or a response-focused implementation intention, and no emotion regulation instructions. The dependent variables were ratings of disgust, valence, arousal, and electrodermal activity. Only perspective-taking implementation intention participants significantly reduced their disgust and unpleasantness as compared to goal-intention and control participants. Arousal and skin conductance did not significantly differ between conditions. The effectiveness of response-focused but not perspective-taking implementation intentions seems to be substantially reduced during sustained exposure duration

Asymmetrical Stripline Based Method for the Electromagnetic Characterization of Metamaterials

International audienceAn experimental method for obtaining the effective electromagnetic parameters of metamaterials is presented. The measurement cell consists in an asymmetric stripline which satisfies certain conditions required for the characterization of this type of materials. The advantages of this cell, its electromagnetic analysis and preliminary experimental and simulated results are shown

Méthode de mesure basée sur une ligne triplaque asymétrique pour la caractérisation électromagnétique des métamatériaux

National audienceUne méthode large bande en ligne triplaque pour mesurer des propriétés électromagnétiques (permittivité e et perméabilité μ complexes) des métamatériaux est présentée. La bande de fréquence, la géométrie et la configuration des champs électromagnétiques de la ligne utilisée sont bien adaptées à la caractérisation de ce type de matériaux. La description de la cellule, les conditions nécessaires pour garantir la validité des mesures et quelques résultats expérimentaux sont présentés

Optimization of electricity / hydrogen cogeneration from generation IV nuclear energy systems

One of the great motivations of studying and developing Generation IV (Gen IV) reactors of VHTR (Very High Temperature Reactor) design concept is their capacity to efficiently produce both electricity and H2 (hydrogen). This study aims at developing an optimization methodology for cogeneration systems of H2 and electricity, from Gen IV nuclear reactors, with respect to energy constraints, economics and conjuncture in term of demand. It lies within a scope of a collaboration between the Laboratoire de Génie Chimique (Toulouse, France) and the Commissariat à l’Energie Atomique (CEA, Cadarache, France) in order to compare various cogeneration systems from both energy and economics viewpoint. This paper presents the results of an optimization study based on the “minimal destruction of exergy” or “exergy loss” concept. This criterion, used within the framework of a mono-objective genetic algorithm optimizer, was applied successfully to electric and heat production from Gen IV systems

Physicians' psychophysiological stress reaction in medical communication of bad news: A critical literature review.

Stress is a common phenomenon in medical professions. Breaking bad news (BBN) is reported to be a particularly distressing activity for physicians. Traditionally, the stress experienced by physicians when BBN was assessed exclusively using self-reporting. Only recently, the field of difficult physician-patient communication has used physiological assessments to better understand physicians' stress reactions. This paper's goals are to (a) review current knowledge about the physicians' psychophysiological stress reactions in BBN situations, (b) discuss methodological aspects of these studies and (c) suggest directions for future research. The seven studies identified all used scenarios with simulated patients but were heterogeneous with regard to other methodological aspects, such as the psychophysiological parameters, time points and durations assessed, comparative settings, and operationalisation of the communication scenarios. Despite this heterogeneity, all the papers reported increases in psychological and/or physiological activation when breaking bad news in comparison to control conditions, such as history taking or breaking good news. Taken together, the studies reviewed support the hypothesis that BBN is a psychophysiologically arousing and stressful task for medical professionals. However, much remains to be done. We suggest several future directions to advance the field. These include (a) expanding and refining the conceptual framework, (b) extending assessments to include more diverse physiological parameters, (c) exploring the modulatory effects of physicians' personal characteristics (e.g. level of experience), (d) comparing simulated and real-life physician-patient encounters and (e) combining physiological assessment with a discourse analysis of physician-patient communication

Autonomic nervous system reactivity within the valence-arousal affective space: modulation by sex and age

In the present study, we examined how sex and age shape cardiovascular, electrodermal, and pupillary reactivity to picture series within the valence-arousal affective space in a sample of 176 healthy younger, middle-aged, and older men and women. Across participants, heart rate (HR) decelerated with increasing self-reported unpleasantness, whereas skin conductance level (SCL) and pupil size (PS) increased with increasing self-rated arousal. Systolic (SBP) and diastolic (DBP) blood pressure increased with increasing self-rated arousal when valence was pleasant but much less when valence was unpleasant. Compared to women, men exhibited a stronger correlation between valence and HR and an SBP response characterized by larger increases for pleasant high-arousal states and lower change scores for unpleasant low- and high-arousal and pleasant low-arousal states. Men's largest SCL change scores were for pleasant high-arousal states, whereas women's largest SCL change scores were for unpleasant high-arousal states. The arousal-PS relationship was stronger among women, in particular for unpleasant series. From younger to older age, there were decreases in the strength of the valence-HR, arousal-SCL, and arousal-PS relationships. Older adults had larger overall increases in SBP and DBP than younger adults, but the relationships with self-reported valence and arousal were not age dependent. We discuss how the observed sex and age effects may reflect sex and age differences in emotional processing and in basic autonomic nervous system functioning

Content-specific gender differences in emotion ratings from early to late adulthood

The investigation of gender differences in emotion has attracted much attention given the potential ramifications on our understanding of sexual differences in disorders involving emotion dysregulation. Yet, research on content-specific gender differences across adulthood in emotional responding is lacking. The aims of the present study were twofold. First, we sought to investigate to what extent gender differences in the self-reported emotional experience are content specific. Second, we sought to determine whether gender differences are stable across the adult lifespan. We assessed valence and arousal ratings of 14 picture series, each of a different content, in 94 men and 118 women aged 20 to 81. Compared to women, men reacted more positively to erotic images, whereas women rated low-arousing pleasant family scenes and landscapes as particularly positive. Women displayed a disposition to respond with greater defensive activation (i.e., more negative valence and higher arousal), in particular to the most arousing unpleasant contents. Importantly, significant interactions between gender and age were not found for any single content. This study makes a novel contribution by showing that gender differences in the affective experiences in response to different contents persist across the adult lifespan. These findings support the "stability hypothesis" of gender differences across age