Adaptation of egocentric distance perception under telestereoscopic viewing within reaching space

• Published in: Experimental brain research 2010-05, Vol.202 (4), p.825-836
• Main Authors: Priot, Anne-Emmanuelle, Laboissière, Rafael, Sillan, Olivier, Roumes, Corinne, Prablanc, Claude
• Format: Article
• Language: English
• Subjects: Adaptation; Adaptation, Psychological; Adjustment (Psychology); Adult; Applied physiology; Biological and medical sciences; Biomedical and Life Sciences; Biomedicine; Body Image; Calibration; Cognitive science; Darkness; Depth perception; Experiments; Feedback; Feedback, Psychological; Female; Fundamental and applied biological sciences. Psychology; Hand; Human physiology applied to population studies and life conditions. Human ecophysiology; Humans; Life Sciences; Male; Medical sciences; Middle Aged; Motor Activity; Motor control and motor pathways. Reflexes. Control centers of vegetative functions. Vestibular system and equilibration; Neurology; Neurons and Cognition; Neurosciences; Perceptions; Photic Stimulation; Physiological aspects; Psychological aspects; Psychology; Psychomotor Performance; Psychophysics; Research Article; Space Perception; Task Performance and Analysis; Transports. Aerospace. Diving. Altitude; Vertebrates: nervous system and sense organs; Visual Perception; Young Adult
• ISSN: 0014-4819; 1432-1106
• DOI: 10.1007/s00221-010-2188-4

Telestereoscopic viewing provides a method to distort egocentric distance perception by artificially increasing the interpupillary distance. Adaptation to such a visual rearrangement is little understood. Two experiments were performed in order to dissociate the effects of a sustained increased vergence demand, from those of an active calibration of the vergence/distance mapping. Egocentric distances were assessed within reaching space through open-loop pointing to small targets in the dark. During the exposure condition of the first experiment, subjects were instructed to point to the targets without feedback, whereas in the second experiment, hand visual feedback was available, resulting in a modified relationship between vergence-specified distance and reach distance. The visual component of adaptation in the second experiment was assessed on the unexposed hand. In the post-tests of both experiments, subjects exhibited a constant distance overestimation across all targets, with a more than twice larger aftereffect in the second one. These findings suggest two different processes: (1) an alteration in the vergence effort following sustained increased vergence; (2) a calibration of the vergence/distance mapping uncovering the visual component of adaptation.