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Updated: Jul 13, 2026
09:39
Spatial Temporal Analysis of Fieldwise Flow in Microvasculature
Published on: November 18, 2019
Velocity discrimination thresholds for flowfield motions with moving observers
Michael W von Grünau1, Kamala Pilgrim, Rong Zhou
1Department of Psychology, Concordia University, 7141 Sherbrooke St. W., Montreal, Que., Canada. vgrunau@alcor.concordia.ca
Vision Research
|July 27, 2007
Summary
Vertical head bobbing during locomotion can distort visual flow fields. However, the visual system effectively compensates for these distortions, maintaining accurate velocity discrimination during walking and running.
Area of Science:
- Neuroscience
- Vision Science
- Biomechanics
Background:
- Forward locomotion generates visual flow fields crucial for visually guided behavior.
- Locomotion introduces distortions, such as vertical head bobbing, which can affect visual perception.
- Understanding how the visual system compensates for these distortions is vital for explaining visually guided behaviors.
Purpose of the Study:
- To investigate the impact of vertical head bobbing on velocity discrimination thresholds.
- To determine how the visual system compensates for distortions caused by head bobbing during locomotion.
- To compare visual performance during standing, walking, and running.
Main Methods:
- Recorded vertical head and eye movements during treadmill locomotion (standing, walking, running) while fixating.
- Assessed velocity discrimination thresholds in accelerating flow fields under different locomotion conditions.
- Simulated head bobbing effects using pursuit eye movements and analyzed their impact on visual perception.
Main Results:
- Head bobbing noise increased during locomotion compared to standing.
- Velocity discrimination performance remained consistent across standing, walking, and running conditions.
- Simulated head bobbing was compensated by pursuit eye movements but not when it was part of the flow field.
- Distortions from body/head oscillations are compensated, with potentially more efficient mechanisms during running.
Conclusions:
- The visual system exhibits robust compensation mechanisms for head bobbing distortions during locomotion.
- Compensation for head bobbing and visual flow information are processed independently.
- Visual performance is maintained or improved during running compared to walking, suggesting enhanced compensatory strategies.
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