Discrete Visual Samples May Control Locomotor Equilibrium and Foot Positioning in Man

• Published in: Journal of motor behavior 1989-03, Vol.21 (1), p.72-91
• Main Authors: Assaiante, Christine, Marchand, Alain R., Amblard, Bernard
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Cognitive science; Fundamental and applied biological sciences. Psychology; Multimodal perception; Neuroscience; Perception; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology
• ISSN: 0022-2895; 1940-1027
• DOI: 10.1080/00222895.1989.10735466

The static or dynamic visual cues required for equilibrium as well as for foot guidance in visually guided locomotion in man were studied using a variety of locomotion supports and illumination and visual conditions. Stroboscopic illumination (brief flashes) and intermittent lighting (longer flashes) were used to control and to vary the visual sampling frequency of static (positional/orientational) visual cues. There were three main findings: First, visual control of foot positioning during locomotion over discontinuous terrain depends mainly upon static visual cues with a low sampling frequency (about 3 Hz); second, visual control of dynamic equilibrium during locomotion over a narrow support depends mainly upon the availability of high frequency static visual cues (up to about 12 Hz); and third, static visual cues required for equilibrium control are extracted from both the peripheral and the central visual field. Assuming that discrete demands for feedback occur, a simple probabilistic model was proposed, according to which the mean time that elapses following presentation of static visual cues about positions or changes of position accounts for the differences in the difficulty of the various illumination conditions.