Multisensory Integration in Speed Estimation During Self-Motion

This study assessed the relative contributions of visual and proprioceptive/motor information during self-motion in a virtual environment using a speed discrimination task. Subjects wore a head-mounted display and rode a stationary bicycle along a straight path in an empty, seemingly infinite hallway with random surface texture. For each trial, subjects were required to pedal the bicycle along two paths at two different speeds (a standard speed and a comparison speed) and subsequently report whether the second speed travelled was faster than the first. The standard speed remained the same while the comparison speed was varied between trials according to the method of constant stimuli. When visual and proprioceptive/motor cues were provided separately or in combination, the speed discrimination thresholds were comparable, suggesting that either cue alone is sufficient. When the relation between visual and proprioceptive information was made inconsistent by varying optic flow gain, the resulting psychometric functions shifted along the horizontal axis (pedalling speed). The degree of separation between these functions indicated that both optic flow and proprioceptive cues contributed to speed estimation, with proprioceptive cues being dominant. These results suggest an important role for proprioceptive information in speed estimation during self-motion.

[1]  Jennifer L. Campos,et al.  Active navigation and orientation-free spatial representations , 2004, Memory & cognition.

[2]  D. Regan,et al.  Dissociation of discrimination thresholds for time to contact and for rate of angular expansion , 1993, Vision Research.

[3]  P. Perona,et al.  Where is the sun? , 1998, Nature Neuroscience.

[4]  J. Pailhous,et al.  Modulations of the optical flow did not induce locomotor pattern fluctuations in treadmill walking in man. , 1994, Perceptual and motor skills.

[5]  D H Warren,et al.  Spatial Localization under Conflict Conditions: Is There a Single Explanation? , 1979, Perception.

[6]  Anne E. Garing,et al.  Calibration of human locomotion and models of perceptual-motor organization. , 1995, Journal of experimental psychology. Human perception and performance.

[7]  J. Lewis,et al.  Probit Analysis (3rd ed). , 1972 .

[8]  M. Ernst,et al.  Humans integrate visual and haptic information in a statistically optimal fashion , 2002, Nature.

[9]  W. Berger,et al.  Visual influence on human locomotion , 1997 .

[10]  S. Coren,et al.  In Sensation and perception , 1979 .

[11]  Mary K. Kaiser,et al.  Perceived Orientation in Physical and Virtual Environments: Changes in Perceived Orientation as a Function of Idiothetic Information Available , 2002, Presence: Teleoperators & Virtual Environments.

[12]  Peter A. Hancock,et al.  Navigation Training in Virtual Environments , 2001 .

[13]  J. Konczak.  Effects of optic flow on the kinematics of human gait: a comparison of young and older adults. , 1994, Journal of motor behavior.

[14]  J. Loomis,et al.  Immersive virtual environment technology as a basic research tool in psychology , 1999, Behavior research methods, instruments, & computers : a journal of the Psychonomic Society, Inc.

[15]  B. Johansson.  Chapter 25: Experimental models of altering the blood-brain barrier , 1992 .

[16]  Michael S. Landy,et al.  Integration of stereopsis and motion shape cues , 1994, Vision Research.

[17]  Horst Mittelstaedt,et al.  Idiothetic navigation in humans: estimation of path length , 2001, Experimental Brain Research.

[18]  William H Warren,et al.  Path Integration from Optic Flow and Body Senses in a Homing Task , 2002, Perception.

[19]  Sarah S. Chance,et al.  Spatial Updating of Self-Position and Orientation During Real, Imagined, and Virtual Locomotion , 1998 .

[20]  Yukie Saito,et al.  Integration of Stereopsis and Motion Shape Cues , 1993 .

[21]  Jack M. Loomis,et al.  Locomotion Mode Affects the Updating of Objects Encountered During Travel: The Contribution of Vestibular and Proprioceptive Inputs to Path Integration , 1998, Presence.

[22]  D J Hannon,et al.  Eye movements and optical flow. , 1990, Journal of the Optical Society of America. A, Optics and image science.

[23]  M. Goodale,et al.  A mammalian model of optic-flow utilization in the control of locomotion , 2004, Experimental Brain Research.

[24]  F. Bremmer,et al.  The use of optical velocities for distance discrimination and reproduction during visually simulated self motion , 1999, Experimental Brain Research.

[25]  B. Frost,et al.  Computation of different optical variables of looming objects in pigeon nucleus rotundus neurons , 1998, Nature Neuroscience.

[26]  J. J. Denier van der Gon,et al.  Integration of proprioceptive and visual position-information , 1999 .

[27]  P. Stappers,et al.  Matching Proprioceptive to Visual Speed Affected by Nonkinematic Parameters , 1996, Perceptual and motor skills.

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

[29]  E Brenner,et al.  Detecting Changes in One's Own Velocity from the Optic Flow , 1994, Perception.

[30]  J M Flach,et al.  Sources of optical information useful for perception of speed of rectilinear self-motion. , 1990, Journal of experimental psychology. Human perception and performance.

[31]  J. Gaddum.  Probit Analysis , 1948, Nature.

[32]  Roy A. Ruddle,et al.  Navigating Large-Scale Virtual Environments: What Differences Occur Between Helmet-Mounted and Desk-Top Displays? , 1999, Presence: Teleoperators & Virtual Environments.

[33]  W. Berger,et al.  Visual influence on human locomotion Modulation to changes in optic flow , 1997, Experimental Brain Research.

[34]  D. Wolpert,et al.  When Feeling Is More Important Than Seeing in Sensorimotor Adaptation , 2002, Current Biology.

[35]  J. Thomson,et al.  Studies in perception and action V , 1999 .

[36]  Earl Hunt,et al.  The Transfer of Spatial Knowledge in Virtual Environment Training , 1998, Presence.

[37]  M. Bonnard,et al.  Interaction between different sensory cues in the control of human gait , 2002, Experimental Brain Research.

[38]  M. Landy,et al.  A perturbation analysis of depth perception from combinations of texture and motion cues , 1993, Vision Research.

[39]  Anthony E. Richardson,et al.  Spatial knowledge acquisition from maps and from navigation in real and virtual environments , 1999, Memory & cognition.

[40]  Lee Dn,et al.  The optic flow field: the foundation of vision. , 1980 .

[41]  Jennifer L. Campos,et al.  Multisensory integration in the estimation of relative path length , 2003, Experimental Brain Research.

[42]  Kay M. Stanney,et al.  Duration and Exposure to Virtual Environments: Sickness Curves During and Across Sessions , 2000, Presence: Teleoperators & Virtual Environments.

[43]  R. Hetherington.  The Perception of the Visual World , 1952 .

[44]  J. Pailhous,et al.  Unintentional modulations of human gait by optical flow , 1990, Behavioural Brain Research.