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Updated: Aug 11, 2026
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Measuring Attention and Visual Processing Speed by Model-based Analysis of Temporal-order Judgments
Published on: January 23, 2017
The temporal properties of first- and second-order vision
1Cognitive Science Research Centre, School of Psychology, University of Birmingham, Edgbaston, B15 2TT, Birmingham, UK. a.j.schofield@bham.ac.uk
Vision Research
|August 1, 2000
Summary
This study reveals that the visual system
Area of Science:
- Visual neuroscience
- Perceptual psychology
- Image processing
Background:
- Human vision processes luminance (first-order) and contrast (second-order) information via distinct mechanisms.
- Previous research suggested second-order visual processing is slower than first-order.
Purpose of the Study:
- To quantitatively assess and compare the temporal dynamics of first- and second-order visual processing at perceptual threshold.
- To investigate the influence of dynamic visual noise on these temporal properties.
Main Methods:
- Utilized temporal integration and two-pulse summation psychophysical tasks.
- Derived impulse response functions from two-pulse summation data.
- Calculated temporal frequency response functions from impulse responses.
- Tested three stimulus types: luminance gratings, luminance-modulated noise, and contrast-modulated noise.
Main Results:
- First-order luminance gratings elicited transient, bandpass responses.
- Adding dynamic noise to luminance gratings resulted in sustained, low-pass responses.
- Second-order contrast-modulated noise also produced sustained, low-pass responses, with temporal integration times similar to the noise-added first-order case.
Conclusions:
- Second-order visual processing may not be as sluggish as previously assumed.
- The temporal characteristics of second-order vision are comparable to first-order vision under noisy conditions.
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