Does Friendship Influence Space Perception? With Particular Reference to the Curse of the Suspicious Participants

Do Friendship Influence Space Perception? With Particular Reference to the Curse of the Suspicious Participants Nicolas Morgado (nicolas.morgado@upmf-grenoble.fr) Laboratoire de Psychologie et Neurocognition (CNRS), Universite Pierre-Mendes-France, 38040 Grenoble, France Dominique Muller (dominique.muller@upmf-grenoble.fr) Laboratoire Interuniversitaire de Psychologie, Institut Universitaire de France et Universite Pierre-Mendes-France, 38040 Grenoble, France Mathieu Pinelli (mathieu.pinelli@upmf-grenoble.fr) Laboratoire de Psychologie et Neurocognition (CNRS), Universite Pierre-Mendes-France, 38040 Grenoble, France Eric Guinet (eric.guinet@upmf-grenoble.fr) Laboratoire de Psychologie et Neurocognition (CNRS), Universite Pierre-Mendes-France, 38040 Grenoble, France Edouard Gentaz (edouard.gentaz@unige.ch) Universite de Geneve / FAPSE UNI MAIL ; 40, Boulevard du Pont-d'Arve 1211 Geneve 4 Richard Palluel-Germain (richard.palluel@upmf-grenoble.fr) Laboratoire de Psychologie et Neurocognition (CNRS), Universite Pierre-Mendes-France, 38040 Grenoble, France Abstract In this study, we tested the hypothesis that social relationships affect the perception of distance. When participants imagined passing through a wall and a disliked-person, they perceived shorter aperture widths than when they intended to pass between a wall and a liked-person. This result was observed only for passable apertures suggesting that social constraints may influence visual perception only when people can actually perform this action. We discuss the results according to an embodied approach to visual perception but also with an alternative explanation in terms of possible demand characteristics. We also discuss some methodological points supposed to improve the validity of such experiments. Keywords: Space Perception; Embodiement, Psychosocial Resources; Affective Closeness; Demand Characteristics Introduction According to Proffitt and Linkenauger (2013) the visual perception of space depends on the phenotype of the perceiver. More precisely, the optical information would be scaled on the morphological, physiological, and behavioral properties of the body. For instance, decreasing people’s ability to reach an object leads them to perceive it as being farther away (e.g., Lourenco & Longo, 2009; Morgado, Gentaz, Guinet, Osiurak, & Palluel-Germain, in press). Previous works tried to extend this account to the influence of social factors on visual perception (Chambon, 2009; Harber, Yeung, & Iacovelli, 2011; Morgado, Muller, Gentaz, & Palluel-Germain, 2011). For example, Schnall, Harber, Stefanucci, & Proffitt (2008) observed that people underestimate the slant of a steep hill when they are accompanied by a friend instead of being alone. According to the authors, this difference in slant estimation reflects that social support, as a social resource, can compensate the potential effort associated with climbing the hill and thus reduces its perceived steepness. In some cases, however, the social constraints associated with a given action constitute a cost rather than a resource. Previous works suggest that people maintain a personal space around them and that they feel discomfort when someone invades this space (Hayduk, 1983). Moreover, this discomfort seems to increase as the physical interpersonal distance decrease (Hayduk, 1981). Interestingly, the discomfort associated with personal space invasion seems to vary according to the social relationship (Sundstrom & Altman, 1976). Consistent with these findings, we recently observed that people’s action-scaled perception of a space between two acquaintances is correlated with the participants’ affective closeness toward these acquaintances (Morgado et al., 2011). Indeed, the closer participants felt to their classmates, the more passable the space between the classmates pictures appeared and the less space they needed to pass. These results might suggest that participants perceived the space between the two classmate pictures (i.e., the aperture width) differently because of the closeness feeling. In the present study, we aimed to investigate further whether social relationships influence the visual perception of an aperture between a wall and an acquaintance. More precisely, participants had to estimate the width of an aperture between the picture of a wall and that of a human figure evoking a liked person or a disliked person. Participants also indicated if the aperture was wide enough to allow them to pass. Our hypothesis was that the participants from the disliked-person group should perceive smaller apertures than participants from the liked-person