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Updated: Jul 31, 2026
08:04
Measuring Sensitivity to Viewpoint Change with and without Stereoscopic Cues
Published on: December 4, 2013
Modulation of perceived contrast by a moving surround.
1NTT Communication Science Laboratories, Atsugi-shi, Morinosato-Wakamiya 3-1, 243-0198, Kanagawa, Japan. tatsuto@apollo3.brl.ntt.co.jp
Vision Research
|August 29, 2000
Summary
The perceived contrast of moving patterns changes based on surrounding motion. Contrast reduction occurs with similar speeds, while enhancement happens with faster surrounds and specific temporal frequency differences.
Area of Science:
- Visual Perception
- Neuroscience
- Computational Vision
Background:
- Perceived contrast is influenced by surrounding visual elements.
- Understanding suprathreshold perception of moving patterns is crucial for visual processing models.
Purpose of the Study:
- To investigate how surround motion (direction and speed) affects the perceived contrast of a central moving pattern.
- To identify the conditions leading to contrast reduction and enhancement in dynamic visual stimuli.
Main Methods:
- Subjects performed contrast matching tasks for a central grating pattern surrounded by moving patterns.
- Systematic variation of temporal frequency, Michelson contrast, and movement direction for both center and surround patterns.
- Analysis of perceived contrast based on differences in velocity and temporal frequency between center and surround.
Main Results:
- Contrast reduction was maximal when center and surround shared the same velocity (velocity selectivity).
- Contrast enhancement occurred when the surround moved faster than the center, provided a significant temporal frequency difference (>10-20 Hz).
- Contrast reduction was more pronounced with higher surround contrasts and lower center contrasts, while enhancement was less affected by contrast levels.
Conclusions:
- Contrast perception of moving patterns is mediated by directionally-selective mechanisms, except at high temporal frequencies.
- Findings suggest both lateral inhibition and excitatory connections between motion-encoding units contribute to contrast gain control.
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