Schaer M.,Office Medico Pedagogique |
Schaer M.,University of Zürich |
Poryazova R.,University of Zürich |
Schwartz S.,University of Geneva |
And 3 more authors.
Journal of Sleep Research | Year: 2012
The sleep-wake disorder narcolepsy with cataplexy is associated with the loss of hypocretin-(orexin-) producing neurons in the lateral hypothalamus. Several studies have reported abnormal cerebral activation in patients with narcolepsy with cataplexy. It remains unclear, however, whether these functional changes are related to structural alterations, particularly at the cortical level. To quantify structural brain changes associated with narcolepsy with cataplexy, we used high-resolution T1-weighted magnetic resonance imaging (MRI) in 12 patients compared with 12 healthy participants matched for age and gender. Subcortical and regional cortical volumes were measured using a method unbiased by non-linear registration. Further whole-brain analyses were conducted, measuring cortical characteristics, such as cortical thickness and gyrification, at thousands of points across each hemisphere using validated algorithms. Statistical analyses accounted for an effect of age and gender. We observed decreased cortical volume in the left paracentral lobule and increased cortical volume in the left caudal part of the middle frontal gyrus in narcoleptic patients compared with controls. Cortical thickness in prefrontal areas was inversely correlated with the severity of narcolepsy. Further, we observed several clusters of cortical thinning in patients with childhood or adolescent onset of narcolepsy compared with patients with adult onset of the disease. Our results suggest that specific anatomical changes may differentiate subgroups of narcolepsy patients with different clinical profiles (such as varying symptom severity or different age at onset). Future studies with larger groups of sleepy patients are required to assess whether distinct patterns of anatomical changes may distinguish narcolepsy from non-hypocretin-deficient hypersomnia disorders. © 2012 European Sleep Research Society.
Robineau F.,University Hospitals Geneva Medical Center |
Robineau F.,Geneva Neuroscience Center |
Rieger S.W.,Geneva Neuroscience Center |
Rieger S.W.,Swiss Center for Affective science |
And 16 more authors.
NeuroImage | Year: 2014
Recent advances in neurofeedback based on real-time functional magnetic resonance imaging (fMRI) allow for learning to control spatially localized brain activity in the range of millimeters across the entire brain. Real-time fMRI neurofeedback studies have demonstrated the feasibility of self-regulating activation in specific areas that are involved in a variety of functions, such as perception, motor control, language, and emotional processing. In most of these previous studies, participants trained to control activity within one region of interest (ROI). In the present study, we extended the neurofeedback approach by now training healthy participants to control the interhemispheric balance between their left and right visual cortices. This was accomplished by providing feedback based on the difference in activity between a target visual ROI and the corresponding homologue region in the opposite hemisphere. Eight out of 14 participants learned to control the differential feedback signal over the course of 3 neurofeedback training sessions spread over 3. days, i.e., they produced consistent increases in the visual target ROI relative to the opposite visual cortex. Those who learned to control the differential feedback signal were subsequently also able to exert that control in the absence of neurofeedback. Such learning to voluntarily control the balance between cortical areas of the two hemispheres might offer promising rehabilitation approaches for neurological or psychiatric conditions associated with pathological asymmetries in brain activity patterns, such as hemispatial neglect, dyslexia, or mood disorders. © 2014 Elsevier Inc.
Dardard F.,Telecom ParisTech |
Gnecco G.,IMT Institute for Advanced Studies |
Glowinski D.,Swiss Center for Affective science
Transactions on Interactive Intelligent Systems | Year: 2016
The aim of the present work is to analyze automatically the leading interactions between the musicians of a string quartet, using machine-learning techniques applied to nonverbal features of the musicians' behavior, which are detected through the help of a motion-capture system. We represent these interactions by a graph of "influence" of the musicians, which displays the relations "is following" and "is not following" with weighted directed arcs. The goal of the machine-learning problem investigated is to assign weights to these arcs in an optimal way. Since only a subset of the available training examples are labeled, a semisupervised support vector machine is used, which is based on a linear kernel to limit its model complexity. Specific potential applications within the field of human-computer interaction are also discussed, such as e-learning, networked music performance, and social active listening.
Billieux J.,University of Geneva |
Billieux J.,Swiss Center for Affective science |
Chanal J.,University of Geneva |
Khazaal Y.,University of Geneva |
And 7 more authors.
Psychopathology | Year: 2011
Background: Massively Multiplayer Online Role-Playing Games (MMORPGs) are video games in which a large number of players interact with one another in a persistent virtual world. MMORPGs can become problematic and result in negative outcomes in daily living (e.g. loss of control on gaming behaviors, compromised social and individual quality of life). The aim of the present study is to investigate psychological predictors of problematic involvement in MMORPGs. Sampling and Methods: Fifty-four males who played MMORPGs regularly were recruited in cybercafés and screened using the UPPS Impulsive Behavior Scale (which assesses 4 facets of impulsivity) and the Motivation to Play Online Questionnaire (which assesses personal motives to play online). Negative consequences due to excessive time spent on the Internet were assessed with the Internet Addiction Test. Results: Multiple regression analysis showed that problematic use of MMORPGs is significantly predicted by: (1) high urgency (b = 0.45), and (2) a motivation to play for immersion (b = 0.35). Conclusion: This study showed that, for certain individuals (who are characterized by a proneness to act rashly in emotional contexts and motivated to play to be immersed in a virtual world), involvement in MMORPGs can become problematic and engender tangible negative consequences in daily life. Copyright © 2011 S. Karger AG, Basel.
Oud B.,University of Zürich |
Coppin G.,Swiss Center for Affective science |
Coppin G.,University of Geneva
Journal of Neuroscience | Year: 2012
Shall I go see a movie tonight, or rather buy some Chinese food? Obviously, such choices between different classes of goods ("reward types") are conceptually complex and methodologically challenging to investigate. Yet, they occur frequently in everyday life. How, then, does the brain solve such problems? The view that diverse behavioral acts and sensory stimuli may be compared via a value signal that is computed on a common scale, much like an internal currency (Montague and Berns, 2002), is gaining traction in decision neuroscience and neuroeconomics. According to this notion, a decision value is computed for each option. These are then compared,andthe optionwith thehighest decision value is most likely chosen. Such comparisons require that decision values areonthe same scale-which is what the notion of a common currency captures. © 2012 the authors.
Allali G.,University of Geneva |
Van Der Meulen M.,University of Geneva |
Van Der Meulen M.,University Hospitals Geneva Medical Center |
Beauchet O.,University of Angers |
And 5 more authors.
Journals of Gerontology - Series A Biological Sciences and Medical Sciences | Year: 2014
Background. Aging is often associated with modifications of gait. Recent studies have revealed a strong relationship between gait and executive functions in healthy and pathological aging. We hypothesized that modification of gait due to aging may be related to changes in frontal lobe function. Methods. Fourteen younger (27.0±3.6 years) and 14 older healthy adults (66.0±3.5 years) performed a motor imagery task of gait as well as a matched visual imagery task. Task difficulty was modulated to investigate differential activation for precise control of gait. Task performance was assessed by recording motor imagery latencies, eye movements, and electromyography during functional magnetic resonance imaging scanning. Results. Our results showed that both healthy older and young adults recruited a network of brain regions comprising the bilateral supplementary motor cortex and primary motor cortex, right prefrontal cortex, and cerebellum, during motor imagery of gait. We observed an age-related increase in brain activity in the right supplementary motor area (BA6), the right orbitofrontal cortex (BA11), and the left dorsolateral frontal cortex (BA10). Activity in the left hippocampus was significantly modulated by task difficulty in the elderly participants. Executive functioning correlated with magnitude of increases in right primary motor cortex (BA4) during the motor imagery task. Conclusions. Besides demonstrating a general overlap in brain regions recruited in young and older participants, this study shows age-related changes in cerebral activation during mental imagery of gait. Our results underscore the importance of executive function (dorsolateral frontal cortex) and spatial navigation or memory function (hippocampus) in gait control in elderly individuals. © The Author 2013.
Korb S.,International School for Advanced Studies |
Malsert J.,Swiss Center for Affective science |
Malsert J.,University of Geneva |
Rochas V.,University of Geneva |
And 7 more authors.
Cortex | Year: 2015
Under theories of embodied emotion, exposure to a facial expression triggers facial mimicry. Facial feedback is then used to recognize and judge the perceived expression. However, the neural bases of facial mimicry and of the use of facial feedback remain poorly understood. Furthermore, gender differences in facial mimicry and emotion recognition suggest that different neural substrates might accompany the production of facial mimicry, and the processing of facial feedback, in men and women. Here, repetitive transcranial magnetic stimulation (rTMS) was applied to the right primary motor cortex (M1), the right primary somatosensory cortex (S1), or, in a control condition, the vertex (VTX). Facial mimicry of smiles and emotion judgments were recorded in response to video clips depicting changes from neutral or angry to happy facial expressions. While in females rTMS over M1 and S1 compared to VTX led to reduced mimicry and, in the case of M1, delayed detection of smiles, there was no effect of TMS condition for males. We conclude that in female participants M1 and S1 play a role in the mimicry and in the use of facial feedback for accurate processing of smiles. © 2015 Elsevier Ltd.
Gentsch K.,Swiss Center for Affective science |
Gentsch K.,University of Geneva |
Grandjean D.,Swiss Center for Affective science |
Grandjean D.,University of Geneva |
Scherer K.R.,Swiss Center for Affective science
Biological Psychology | Year: 2014
Componential theories assume that emotion episodes consist of emergent and dynamic response changes to relevant events in different components, such as appraisal, physiology, motivation, expression, and subjective feeling. In particular, Scherer's Component Process Model hypothesizes that subjective feeling emerges when the synchronization (or coherence) of appraisal-driven changes between emotion components has reached a critical threshold. We examined the prerequisite of this synchronization hypothesis for appraisal-driven response changes in facial expression. The appraisal process was manipulated by using feedback stimuli, presented in a gambling task. Participants' responses to the feedback were investigated in concurrently recorded brain activity related to appraisal (event-related potentials, ERP) and facial muscle activity (electromyography, EMG). Using principal component analysis, the prediction of appraisal-driven response changes in facial EMG was examined. Results support this prediction: early cognitive processes (related to the feedback-related negativity) seem to primarily affect the upper face, whereas processes that modulate P300 amplitudes tend to predominantly drive cheek region responses. © 2013 Elsevier B.V.
Goudbeek M.,University of Tilburg |
Scherer K.,Swiss Center for Affective science
Journal of the Acoustical Society of America | Year: 2010
The important role of arousal in determining vocal parameters in the expression of emotion is well established. There is less evidence for the contribution of emotion dimensions such as valence and potency/control to vocal emotion expression. Here, an acoustic analysis of the newly developed Geneva Multimodal Emotional Portrayals corpus, is presented to examine the role of dimensions other than arousal. This corpus contains twelve emotions that systematically vary with respect to valence, arousal, and potency/control. The emotions were portrayed by professional actors coached by a stage director. The extracted acoustic parameters were first compared with those obtained from a similar corpus [Banse and Scherer (1996). J. Pers. Soc. Psychol. 70, 614-636] and shown to largely replicate the earlier findings. Based on a principal component analysis, seven composite scores were calculated and were used to determine the relative contribution of the respective vocal parameters to the emotional dimensions arousal, valence, and potency/control. The results show that although arousal dominates for many vocal parameters, it is possible to identify parameters, in particular spectral balance and spectral noise, that are specifically related to valence and potency/control. © 2010 Acoustical Society of America.
Glowinski D.,University of Genoa |
Dael N.,Swiss Center for Affective science |
Camurri A.,University of Genoa |
Volpe G.,University of Genoa |
And 2 more authors.
IEEE Transactions on Affective Computing | Year: 2011
This paper presents a framework for analysis of affective behavior starting with a reduced amount of visual information related to human upper-body movements. The main goal is to individuate a minimal representation of emotional displays based on nonverbal gesture features. The GEMEP (Geneva multimodal emotion portrayals) corpus was used to validate this framework. Twelve emotions expressed by 10 actors form the selected data set of emotion portrayals. Visual tracking of trajectories of head and hands were performed from a frontal and a lateral view. Postural/shape and dynamic expressive gesture features were identified and analyzed. A feature reduction procedure was carried out, resulting in a 4D model of emotion expression that effectively classified/grouped emotions according to their valence (positive, negative) and arousal (high, low). These results show that emotionally relevant information can be detected/measured/obtained from the dynamic qualities of gesture. The framework was implemented as software modules (plug-ins) extending the EyesWeb XMI Expressive Gesture Processing Library and is going to be used in user centric, networked media applications, including future mobiles, characterized by low computational resources, and limited sensor systems. © 2011 IEEE.