Multisensory Origin of the Subjective First-Person Perspective: Visual, Tactile, and Vestibular Mechanisms

Christian Pfeiffer (1) , Christophe Lopez (2) , Valentin Schmutz (1) , Julio Angel Duenas (3) , Roberto Martuzzi (1) , Olaf Blanke (4, 1)

1 EPFL - Ecole Polytechnique Fédérale de Lausanne
2 LNIA - Laboratoire de Neurosciences intégratives et adaptatives
3 ETH Zürich - Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich]
4 Department of Neurology

In three experiments we investigated the effects of visuo-tactile and visuo-vestibular conflict about the direction of gravity on three aspects of bodily self-consciousness: self-identification, self-location, and the experienced direction of the first-person perspective. Robotic visuo-tactile stimulation was administered to 78 participants in three experiments. Additionally, we presented participants with a virtual body as seen from an elevated and downward-directed perspective while they were lying supine and were therefore receiving vestibular and postural cues about an upward-directed perspective. Under these conditions, we studied the effects of different degrees of visuo-vestibular conflict, repeated measurements during illusion induction, and the relationship to a classical measure of visuo-vestibular integration. Extending earlier findings on experimentally induced changes in bodily self-consciousness, we show that self-identification does not depend on the experienced direction of the first-person perspective, whereas self-location does. Changes in bodily self-consciousness depend on visual gravitational signals. Individual differences in the experienced direction of first-person perspective correlated with individual differences in visuo-vestibular integration. Our data reveal important contributions of visuo-vestibular gravitational cues to bodily self-consciousness. In particular we show that the experienced direction of the first-person perspective depends on the integration of visual, vestibular, and tactile signals, as well as on individual differences in idiosyncratic visuo-vestibular strategies.

Mots clés: Vision; Robotics; Sensory perception; Self-consciousness; Visual signals; Analysis of variance; Acceleration; Acoustics

Domaines: Neurosciences [q-bio.NC]

Christian Pfeiffer, Christophe Lopez, Valentin Schmutz, Julio Angel Duenas, Roberto Martuzzi, et al.. Multisensory Origin of the Subjective First-Person Perspective: Visual, Tactile, and Vestibular Mechanisms. PLoS ONE, 2013, 8 (4), pp.e61751. ⟨10.1371/journal.pone.0061751⟩. ⟨hal-01449853⟩