000			04942cam a2200397 4500500
005			20250125131248.0
041			_afre
042			_adc
100	1	0	_aMars, Franck _eauthor
700	1	0	_a Bringoux, Lionel _eauthor
700	1	0	_a Cian, Corinne _eauthor
700	1	0	_a Barraud, Pierre-Alain _eauthor
700	1	0	_a Raphel, Christian _eauthor
700	1	0	_a Vercher, Jean-Louis _eauthor
245	0	0	_aPerception de la verticale avec un cadre visuel solidaire de la tête : implications pour l'utilisation des visiocasques
260			_c2005.
500			_a85
520			_aRÉSUMÉ Les travaux présentés visent à déterminer comment la présence de références visuelles fixes dans le référentiel de la tête peut influencer la perception de l’orientation spatiale. Une première expérience étudie l’influence d’un cadre visuel céphalocentré sur la verticale subjective, lors d’inclinaison de la tête. Une seconde expérience s’intéresse aux effets d’un tel cadre visuel sur la verticale subjective et sur la performance dans une tâche de réorientation de la tête lors d’inclinaisons du corps entier. Les deux études mettent l’accent sur le rôle fondamental du référentiel céphalocentré dans le traitement des informations visuelles pour la perception de l’orientation spatiale. Elles suggèrent qu’un cadre visuel céphalocentré tel qu’on peut le trouver dans un visiocasque peut contribuer à désorienter l’utilisateur, en particulier dans les environnements de réalité augmentée.
520			_aPERCEPTION OF THE VERTICAL WITH A HEAD-FIXED VISUAL FRAME : IMPLICATIONS FOR USING HEAD-MOUNTED DISPLAYS Head-mounted displays are now extensively developed and tested to be used in enhanced reality environments. The technique consists in transmitting synthetic visual information to the user’s eyes in such a way that virtual objects are superimposed on the real world. Some displays give the feeling of viewing a rectangular head-fixed virtual screen with clearly visible contours. In addition, head-mounted displays allow for the presentation of head-fixed visual information to the user and this may be an advantage in some applications, military aeronautics for instance. Presenting head-fixed visual information may not be trivial with regard to actual models of spatial orientation. This study addressed the question of potential disorienting effects associated with head-mounted displays by investigating the influence of a head-fixed visual frame on the perception of the vertical when the head or the whole body was tilted in the frontal plane. In a first experiment, subjects were instructed to indicate the vertical by rotating a visual rod that appeared at the centre of the frame whilst tilting the head in various positions. This performance was compared with the effect on the subjective vertical of a tilted earth-based visual frame without head tilts as well as with the effect of tilting the head without a frame. With the tilted frames, subjects set the rod in an intermediate direction between the gravitational vertical and the orientation of the frame. Errors were substantially larger with a head-fixed visual frame during head tilt than with a tilted earth-based frame. This difference cannot be attributed to the addition of a postural effect caused by the head being tilted. Moreover, continuous vision of the frame when its orientation changed improved performance only when the head and the frame were dissociated, i.e. with an earth-based frame. A second experiment investigated the effects of a head-fixed frame on the subjective vertical and on the voluntary control of head orientation when the whole body was tilted. The effect of a head-fixed frame was contrasted with the effect of a trunk-fixed frame. Results show that the head-fixed frame modified the head behaviour when subjects were instructed to align the head with the trunk. These errors contributed to an increase in the visual frame influence on the subjective vertical. Results of both experiments suggest that integrating visual information in the head-centric reference frame is crucial for spatial orientation. This property of the perceptual system may be relevant for the design and use of head-mounted displays.
690			_aVisiocasque
690			_aRéalité augmentée
690			_aIntégration sensorielle
690			_aRéferentiels spatiaux
690			_aOrientation spatiale
690			_aVision
690			_aVerticale subjective
690			_aReference Frames
690			_aSensory Integration
690			_aSpatial Orientation
690			_aSubjective Vertical
690			_aHead-Mounted Displays
690			_aEnhanced Reality
690			_aVision
786	0		_nLe travail humain | 68 | 2 | 2005-06-01 | p. 125-152 | 0041-1868
856	4	1	_uhttps://shs.cairn.info/revue-le-travail-humain-2005-2-page-125?lang=fr&redirect-ssocas=7080
999			_c991067 _d991067