INFLUENCES ÉGOCENTRÉES SUR LA PERCEPTION DE L'ESPACE GÉOCENTRÉ - OBJECTIVATION AU TRAVERS DE L'ESTIMATION DU FRANCHISSEMENT D'OBSTACLES HAUTS

• Bourrelly Aurore

• Spatial perception
• Postural orientation
• Visually induced self-motion
• Optic flow
• Egocentric
• Geocentric
• Allocentric refrence frame
• Multisensorial integration

Perceiving space is a relevant task in determining our relationships with the environment. In behavioral neuroscience, investigating this spatial relationship can classically be explored with two theoretical approaches. The first one uses direct perception to describe the spatial relationships, involving affordances (i.e. the action ability naturally offer by the environment). The other one investigates the cognitive aspect of perception implying the use of spatial representation process. The later one traduces the existence of represented states which can be described through the interaction of different stable states called spatial reference frames. The present work investigates the contribution of the egocentric reference frame (body- related) on the perception of the geocentric space (earth-based). This was questioned through two research lines, (i) the origin of egocentric influence previously observed in darkness upon geocentric perception, (ii) the existence of the egocentric phenomenon in an enriched visual scene. To answer these questions, four experiments were conducted where the paradigm of passing under high obstacles was used. Overall, these results stress the powerful and complex aspect of the egocentric phenomenon observed upon geocentric perception. This work, discussed in term of interpenetrability between reference frames, provide an interesting support on the way how spatial reference frames are used in perceiving space.