<p>Recent studies have linked expressive suppression to impairments in interpersonal functioning, but the mechanism underlying this relationship has not been well articulated. One possibility is that the individual who engages in expressive suppression is impaired in perceiving the emotions of others, a critical ability in successful interpersonal functioning. In the current study, participants were presented with a series of photographs of facial expressions that were manipulated so that they appeared to "morph" from neutral into full emotion expressions. As they viewed these images, participants were instructed to identify the expression as quickly as possible, by selecting one of the six emotion labels (happiness, sadness, fear, anger, surprise, and disgust) on the screen. Prior to this task, participants were randomized to one of three groups: instructed to mimic the expressions on the screen, instructed to suppress all emotion expressions, or not given specific instructions on how to control expressions (the control group). The speed with which participants accurately identified emotional expressions (emotion sensitivity) was the primary variable of interest. Overall, participants in the suppression condition were found to be slower to accurately identify emotions, while no statistically-significant differences were found between the mimicry and no-instructions conditions. The decreased emotion sensitivity in the suppression group could not be accounted for by impulsive responding, decreased sensitivity at full expression, or perceived difficulty of task.</p> / Dissertation

Underlättar kongruens mellan sinnestillstånd och påstående (vad gäller dess värdeladdning) vid bedömning av ett påståendes sanningshalt? Denna fråga uppkom via studier av embodiment och lögner, forskning från de båda områdena påvisar nämligen att olika ”kroppsliga signaler” kan hjälpa oss att avslöja om andra människor ljuger. Frågan har undersökts via en faktoriell design med repeterade mätningar där deltagarna försattes i olika sinnestillstånd varpå de utsattes för olika stimuli och fick göra olika bedömningar. Resultatet visade att kongruenta betingelser varken underlättar eller påskyndar vid bedömning av ett påståendes sanningshalt, däremot erhölls ett signifikant resultat som indikerade att kongruenta betingelser ökar människans konfidensnivå (högre grad av säkerhet vad gäller att en korrekt bedömning gjorts) vid bedömning av falska påståenden.

Can a common facial cosmetic procedure buffer against the negative impact of adverse social interactions? This pilot tested the hypothesis that an injection of botulinum toxin (Botox) to the corrugator supercilii muscles used in anger, compared to a placebo injection to the same location, will reduce the impact of social rejection on mood, self-esteem, control, meaningful existence, and aggression. Freezing facial musculature was hypothesized to alter the first physical signal of negative emotional reactions, thereby reducing the impact of social rejection on distress and aggression. This was the first study using Botox to examine the effects of reduced facial feedback on felt emotions during social interactions. While the findings in this pilot were not statistically significant, a trend in the data suggests that the effect was in the opposite direction of the prediction such that participants in the Botox (vs. saline) condition experienced greater feelings of rejection. Further investigation is needed.

La maladie de Parkinson est une affection neurodégénérative principalement associée à la dégénérescence progressive des neurones dopaminergiques du mésencéphale provoquant un dysfonctionnement des noyaux gris centraux. En parallèle de symptômes moteurs bien connus, cette affection entraîne également l’émergence de déficits émotionnels impactant en outre l’expression et la reconnaissance des émotions. Ici, se pose la question d’un déficit de reconnaissance des émotions faciales chez les patients parkinsoniens lié au moins en partie aux troubles moteurs. En effet, selon les théories de simulation des émotions, copier les émotions de l’autre nous permettrait de mieux les reconnaître. Ce serait le rôle du mimétisme facial. Automatique et inconscient, ce phénomène est caractérisé par des réactions musculaires congruentes à l’émotion exprimée par autrui. Dans ce contexte, une perturbation des capacités motrices pourrait conduire à une altération des capacités de reconnaissance des émotions. Or, l’un des symptômes moteurs les plus fréquents dans la maladie de Parkinson, l’amimie faciale, consiste en une perte de la mobilité des muscles du visage. Ainsi, nous avons examiné l’efficience du mimétisme facial dans la maladie de Parkinson, son influence sur la qualité du processus de reconnaissance des émotions, ainsi que l’effet du traitement dopaminergique antiparkinsonien sur ces processus. Pour cela, nous avons développé un paradigme permettant l’évaluation simultanée des capacités de reconnaissance et de mimétisme (corrugator supercilii, zygomaticus major et orbicularis oculi) d’émotions exprimées sur des visages dynamiques (joie, colère, neutre). Cette expérience a été proposée à un groupe de patients parkinsoniens comparé à un groupe de sujets sains témoins. Nos résultats supportent l’hypothèse selon laquelle le déficit de reconnaissance des émotions chez le patient parkinsonien pourrait résulter d’un système « bruité » au sein duquel le mimétisme facial participerait. Cependant, l’altération du mimétisme facial dans la maladie de Parkinson et son influence sur la reconnaissance des émotions dépendraient des muscles impliqués dans l’expression à reconnaître. En effet, ce serait davantage le relâchement du corrugateur plutôt que les contractions du zygomatique ou de l’orbiculaire de l’œil qui nous aiderait à bien reconnaître les expressions de joie. D’un autre côté, rien ne nous permet ici de confirmer l’influence du mimétisme facial sur la reconnaissance des expressions de colère. Enfin, nous avons proposé cette expérience à des patients en condition de traitement habituel et après une interruption temporaire de traitement. Les résultats préliminaires de cette étude apportent des éléments en faveur d’un effet bénéfique du traitement dopaminergique tant sur la reconnaissance des émotions que sur les capacités de mimétisme. L’hypothèse d’un effet bénéfique dit « périphérique » sur la reconnaissance des émotions par restauration du mimétisme facial reste à tester à ce jour. Nous discutons l’ensemble de ces résultats selon les conceptions récentes sur le rôle des noyaux gris centraux et sous l’angle de l’hypothèse de feedback facial. / Parkinson’s disease is a neurodegenerative condition primarily resulting from a dysfunction of the basal ganglia following a progressive loss of midbrain dopamine neurons. Alongside the well-known motor symptoms, PD patients also suffer from emotional disorders including difficulties to recognize and to produce facial emotions. Here, there is a question whether the emotion recognition impairments in Parkinson’s disease could be in part related to motor symptoms. Indeed, according to embodied simulation theory, understanding other people’s emotions would be fostered by facial mimicry. Automatic and non-conscious, facial mimicry is characterized by congruent valence-related facial responses to the emotion expressed by others. In this context, disturbed motor processing could lead to impairments in emotion recognition. Yet, one of the most distinctive clinical features in Parkinson’s disease is facial amimia, a reduction in facial expressiveness. Thus, we studied the ability to mimic facial expression in Parkinson’s disease, its effective influence on emotion recognition as well as the effect of dopamine replacement therapy both on emotion recognition and facial mimicry. For these purposes, we investigated electromyographic responses (corrugator supercilii, zygomaticus major and orbicularis oculi) to facial emotion among patients suffering from Parkinson’s disease and healthy participants in a facial emotion recognition paradigm (joy, anger, neutral). Our results showed that the facial emotion processing in Parkinson’s disease could be swung from a normal to a pathological, noisy, functioning because of a weaker signal-to-noise ratio. Besides, facial mimicry could have a beneficial effect on the recognition of emotion. Nevertheless, the negative impact of Parkinson’s disease on facial mimicry and its influence on emotion recognition would depend on the muscles involved in the production of the emotional expression to decode. Indeed, the corrugator relaxation would be a stronger predictor of the recognition of joy expressions than the zygomatic or orbicularis contractions. On the other hand, we cannot conclude here that the corrugator reactions foster the recognition of anger. Furthermore, we proposed this experiment to a group of patients under dopamine replacement therapy but also during a temporary withdrawal from treatment. The preliminary results are in favour of a beneficial effect of dopaminergic medication on both emotion recognition and facial mimicry. The potential positive “peripheral” impact of dopamine replacement therapy on emotion recognition through restoration of facial mimicry has still to be tested. We discussed these findings in the light of recent considerations about the role of basal ganglia-based circuits and embodied simulation theory ending with the results’ clinical significances.