Effect of gravito-inertial cues on the coding of orientation in pre-attentive vision.
To see if the spatial reference frame used by pre-attentive vision is specified in a retino-centered frame or in a reference frame integrating visual and nonvisual information (vestibular and somatosensory), subjects were centrifuged in a non-pendular cabin and were asked to search for a target distinguishable from distractors by difference in orientation (Treisman's "pop-out" paradigm [1]). In a control condition, in which subjects were sitting immobilized but not centrifuged, this task gave an asymmetric search pattern: Search was rapid and pre-attentional except when the target was aligned with the horizontal retinal/head axis, in which case search was slow and attentional (2). Results using a centrifuge showed that slow/serial search patterns were obtained when the target was aligned with the subjective horizontal axis (and not with the horizontal retinal/head axis). These data suggest that a multisensory reference frame is used in pre-attentive vision. The results are interpreted in terms of Riccio and Stoffregen's "ecological theory" of orientation in which the vertical and horizontal axes constitute independent reference frames (3).
Stivalet
P
P
Centre de Recherches du Service de Santé des Armées, La Tronche, France.
Marendaz
C
C
Barraclough
L
L
Mourareau
C
C
D000328:Adult; D001288:Attention / Q000502:physiology*; D006112:Gravitation; D006801:Humans; D008297:Male; D009068:Movement; D009949:Orientation / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*; D014785:Vision, Ocular / Q000502:physiology*