Related Experiment Video
Updated: Aug 25, 2026

Measuring Attention and Visual Processing Speed by Model-based Analysis of Temporal-order Judgments
Published on: January 23, 2017
Different attentional resources modulate the gain mechanisms for color and luminance contrast
M C Morrone1, V Denti, D Spinelli
1Università Vita-Salute S. Raffaele, Milan, Italy. concetta.morrone@hsr.it
Abstract:
We used an interference paradigm to investigate whether attention is attribute-specific at early levels of visual processing. We show that the peripheral increment thresholds for luminance contrast deteriorate when the observer is currently performing another luminance (form or contrast) discrimination task in central view, but not when he or she is performing a color discrimination task. Similar results were obtained for color increment thresholds, indicating that the interference is specific to contrast modality. The effects are strong and robust over primary task difficulties and perceptual learning levels. Modeling suggests that attention improves contrast sensitivity by modulating the gain of the neuronal response to contrast. These results suggest that attention is parceled in independent resources for luminance and color contrast.
Related Concept Videos
Color Vision
Photoreceptors and Visual Pathways
Anatomy of the Eyeball
Vision
The Retina
Perceptual Constancy
Size constancy is the recognition that an object remains the same size, even when its image on the retina changes. For instance, a bus is perceived to be large enough to carry people, even if it looks tiny from...

