Judgments of eye level in light and in darkness

Subjects judged eye level in the light and in the dark by raising and lowering themselves in a dental chair until a stationary target appeared to be at the level of their eyes. This method reduced the possibility of subjects’ using visible landmarks as reference points for setting eye level during lighted trials, which may have contributed to artificially low estimates of the variability of this judgment in previous studies. Chair settings were 2.5° higher in the dark than in the light, and variability was approximately 66% greater in the dark than in the light. These results are discussed in terms of possible interactions of two separate systems, one sensitive to the orientations of visible surfaces and the other sensitive to bodily and gravitational information.

[1]  Malcolm M. Cohen.  Elevator illusion: Influences of otolith organ activity and neck proprioception , 1973 .

[2]  D. H. Warren,et al.  Sensory conflict in judgments of spatial direction , 1969 .

[3]  M. Bornstein,et al.  Development in Infancy , 1982 .

[4]  A. Edwards,et al.  Body sway and vision. , 1946, Journal of experimental psychology.

[5]  J. Gibson.  The Senses Considered As Perceptual Systems , 1967 .

[6]  The constancy of object orientation: Effects of target inclination , 1972, Psychologische Forschung.

[7]  H. A. Witkin.  Perception of body position and of the position of the visual field. , 1949 .

[8]  Malcolm M. Cohen,et al.  Human spatial orientation in the pitch dimension , 1974 .

[9]  J. Stevens,et al.  Oculoparalytic illusion: visual-field dependent spatial mislocalizations by humans partially paralyzed with curare. , 1982, Science.

[10]  L. Stark,et al.  Role of corollary discharge in space constancy , 1983, Perception & psychophysics.

[11]  Carl Ivar Sandström,et al.  Orientation in the present space , 1951 .

[12]  Wayne L. Shebilske,et al.  Optical insignificance of the nose and the pinocchio effect in free-scan visual straight-ahead judgments , 1976 .

[13]  H SCHOENE,et al.  ON THE ROLE OF GRAVITY IN HUMAN SPATIAL ORIENTATION. , 1964, Aerospace medicine.

[14]  T. Kapteyn,et al.  Effects of visual-vestibular interaction on human posture. , 1977, Advances in oto-rhino-laryngology.

[15]  J. Gibson.  The perception of the visual world , 1951 .

[16]  J. Gibson,et al.  The perceived slant of visual surfaces-optical and geographical. , 1952, Journal of experimental psychology.

[17]  Ian P. Howard,et al.  Human visual orientation , 1982 .

[18]  David N. Lee.  Visual proprioceptive control of stance , 1975 .

[19]  H A WITKIN,et al.  Visual factors in the maintenance of upright posture. , 1950, The American journal of psychology.

[20]  J. I. Niven,et al.  On predictive equations for subjective judgments of vertical and horizon in a force field. , 1968, Acta oto-laryngologica.

[21]  An experimental study concerning visual localization in the horizontal plane. , 1934 .