Visual mental imagery interferes with allocentric orientation judgements.

The subjective visual vertical is determined when a subject judges the orientation of an indicator (e.g. a short line segment) as apparently vertical. The mechanisms that underlie this perceptual performance are usually assumed to be based predominantly on bottom-up processing of primarily vestibular and visual information. However, it is also possible that top-down processes play a role in such abilities. We used an interference paradigm in order to investigate the effects of mental images on the perception of the visual vertical. The results demonstrate for the first time that visual mental imagery can exert the same directional influence on the subjective visual vertical as a perception of the corresponding stimulus.

[1]  S. Kosslyn.  Measuring the visual angle of the mind's eye , 1978, Cognitive Psychology.

[2]  F. Mast,et al.  Assessing Otolith Function by the Subjective Visual Vertical , 1999, Annals of the New York Academy of Sciences.

[3]  D M Merfeld,et al.  Humans use internal models to estimate gravity and linear acceleration , 1999, Nature.

[4]  Laurence R. Young,et al.  Optimal Estimator Model for Human Spatial Orientation a , 1988 .

[5]  Norbert Bischof,et al.  Optic-Vestibular Orientation to the Vertical , 1974 .

[6]  S. Kosslyn,et al.  Neural Systems Shared by Visual Imagery and Visual Perception: A Positron Emission Tomography Study , 1997, NeuroImage.

[7]  X. M. Sauvan,et al.  Orientation Constancy in Neurons of Monkey Visual Cortex , 1999 .

[8]  M. Farah,et al.  Psychophysical evidence for a shared representational medium for mental images and percepts. , 1985, Journal of experimental psychology. General.

[9]  M. Guerraz,et al.  The role of head-centric spatial reference with a static and kinetic visual disturbance , 1998, Perception & psychophysics.

[10]  V. S. Gurfinkel,et al.  Perceptual and automatic aspects of the postural body scheme. , 1991 .

[11]  N. Wade.  Effect of instructions on visual orientation. , 1970, Journal of experimental psychology.

[12]  L. Yardley.  Contribution of somatosensory information to perception of the visual vertical with body tilt and rotating visual field , 1990, Perception & psychophysics.

[13]  M Dieterich,et al.  Vestibular cortex lesions affect the perception of verticality , 1994, Annals of neurology.

[14]  H. Mittelstaedt.  The subjective vertical as a function of visual and extraretinal cues. , 1986, Acta psychologica.