INdividual personality traits and emotion in the Perception-ACTion Loop – IN-PACT

These hypotheses are tested in four workpackages, each containing several studies. Each study requires the collection of data from a large number of participants in order to relate performance on perceptual and/or motor tasks to individual personality traits measured with questionnaires in the general population. Depending on the study, the stimuli are social or non-social and the perceptual tasks are more or less complex: size estimation, judgment of gaze direction, estimation of interpersonal distance, identification of emotions, etc. In parallel with these perceptual tasks, a recording of postural variables is carried out, which objectively measure action tendencies indexed by the forward or backward displacement of the body, or oculomotor variables, which provide information on the observer's visual exploration. Finally, in each study of each WP, the individual traits of the participants are measured with questionnaires used by previous studies in the literature: sensitivity to approach or avoidance, anxiety trait, anger trait , Big Five personality traits (openness, conscientiousness, extraversion, agreeableness, neuroticism), schizotypal traits. The first WP aims to examine the interactions between the perception of facial expressions and action tendencies measured by posturographic recordings as a function of individual traits. The second WP aims to test whether the oculomotor exploration of a social stimulus is modified according to the expression presented and the individual traits of the observer. The third WP examines whether individual traits, reinforcing action tendencies, modulate the perception of non-social stimuli. Finally, the fourth WP replicates some of the tasks from WP1 and 2 with participants with schizotypal traits to examine whether they exhibit heightened action tendencies that would consequently modify their perception.

Our studies show how personality can modulate the effect of emotions on motor and perceptual processes:

• Personality modulates visual exploration of an emotional face: For subtle emotions, people with high scores of neuroticism and anxiety fixate the eyes while those with high scores of extraversion and agreeableness fixate the mouth, respectively diagnostic areas for the detection of negative and positive emotions. At a higher intensity, these behaviors persist only when the emotion matches the personality of the participants -e.g. eye fixation for negative personalities only for fear or anger-.

• Personality modulates action tendencies: While disgust, anger or fear generally trigger avoidance and joy of approach (see Figure B), the measurement of action tendencies on postural behavior is subtle, requires a large number of participants and the use of dynamic stimuli. It can be modulated by other factors such as the direction of the facial gaze and the personality of the observer.

• Personality modulates emotion recognition: our studies did not highlight any effect of neuroticism, extraversion and agreeableness on emotion recognition. Nevertheless, we showed that people with an avoidant temperament (high sensitivity to the behavioral inhibition system and neuroticism) had a better ability to identify emotions compared to non-avoidants but a specific response bias to anger, leading them to over-report this emotion.

• Personality modulates the perception of two crucial social cues for social interactions - gaze direction and interpersonal distance: the adjustment of interpersonal distance and the judgment of the extent of gaze directions directed towards oneself depend on the emotion of others. A shorter distance is preferred for happy faces and a greater distance for disgusted or angry faces (see Figure A). The latter are judged as looking more directly at the observer than happy, neutral or sad faces while fearful faces are judged as looking more at the environment. Personality can modulate these effects. Thus, anxious individuals will prefer a greater distance in the face of anger and will judge sad faces as looking more at the environment.

Our research project contributes to advance theoretical knowledge on perception-action and emotion relationships. By placing emotions at the heart of the perception-action loop, our project highlights how emotion perception influences action tendencies and how action tendencies also modulate the perception of social and non-social stimuli. Moreover, while the link between emotion processing and individual traits is a very current topic in the literature, giving a central role to individual traits in perceptual and motor processes is new and should impact theoretical models of sensorimotor control.

Beyond these scientific considerations, a more unified understanding of the interactions between emotion, perception-action and individual traits is essential, particularly in the clinical field to design assessment and remediation tools adapted to pathologies that affect social behavior. In particular, better understanding the role of emotions in the perception-action loop in people with schizotypal personality traits provides a useful framework for understanding the development of schizophrenia and bipolar spectrum disorders in order to develop prevention strategies and limit the impact on the education and training of young people. Finally, our project could also have a great impact in the field of education. Much research in the fields of psychology, neuroscience and more broadly in the human and social sciences agrees on the importance of the relationship between emotion and cognition for lifelong learning. Learning situations are often rich in emotions and involve the ability to decode the behavior of others and modulate our own reactions. The learner must be able to adapt his behavior to the cognitive and emotional state of the teacher and vice versa, for the learning situation to be effective. A better understanding of the influence of individual traits on learner behaviour will undoubtedly help teachers to take this into account in order to manage and improve interaction during learning. Furthermore, the objective of education has now expanded from the acquisition of technical knowledge and skills to the acquisition of “soft skills” or “social and emotional skills” among which we distinguish the ability to manage one’s emotions (sometimes called emotional intelligence), the ability to communicate and teamwork. Such skills will be necessary throughout our lives, including in professional contexts.

The first results for this ANR were presented in two manuscripts, the first is submitted, the second is under review.

Emotions, far from being passive, can be viewed as an interface between an individual and the environment. Thus, it is not surprising that emotions have been assigned a motivational function, i.e. preparing the body to act through action tendencies such as approach or avoidance behavior. However, despite this functional significance, emotions are almost never examined through the lens of the Perception-Action loop. Some studies have examined how the perception of emotional stimuli an affect action tendencies, assessed using self-report questionnaires, joystick tasks or more directly through posturographic measurement of body sway in passive perception tasks of emotional stimuli. While the perception of disgust or happy stimuli generally induces avoidance or approach tendencies respectively, action patterns associated with anger, sadness and fear are still debated. The contradictory results on these emotions may be related to differences in individual personality traits that could play a role in this relation by accentuating approach or avoidance tendencies. To our knowledge, no prior study has examined the other end of the loop, i.e. the influence of action tendencies on perception. The main objective of the project is then to integrate emotions in the perception-action loop as predispositions to act and to examine how the individual personality traits -from normal to sub-clinical dimensions- may be a major interacting factor in these relations. By placing our research in the theoretical framework of the distance-regulating view of motivation, we postulate 1/ that approach and avoidance tendencies, viewed as a readiness to decrease or increase the physical distance with the environment, should involve changes in the perceptual experience of the observer, and 2/ that individual personality traits should act as reinforcers of action tendencies leading to specific perceptual/motor performances. We will test these hypotheses in four experimental workpackages (WP) by combining for the first time on a large number of participants oculomotor/posturographic measures, perceptual responses on social or non-social stimuli and self-report questionnaires. In the first WP, we will examine the interactions between the perception of facial expressions and action tendencies as a function of the individual traits by using posturographic measures. In the second WP, we will focus on the observer's gaze behavior by looking at whether the perception of different expressions leads to specific oculomotor explorations of faces depending of the observer’s personality traits. In the third WP, we will examine the hypothesis that individual traits, as reinforcers of action tendencies, modulate perception even for non-social stimuli. Finally, in the fourth WP, some of the tasks from WP1-2 will be conducted with individuals with hypomanic and schizotypal traits to examine whether they present exacerbated action tendencies that could modify their perception accordingly. This project should provide a unique opportunity to achieve an integrated view of the place of emotions and the major role of individual traits in the perception-action loop.