Related Experiment Video
Updated: May 16, 2026
04:43
Visualizing Visual Adaptation
Published on: April 24, 2017
Density is a precursor in the perception of visual numerosity: Evidence from adaptation
Frank H Durgin1, Abigail Love1, Grace Taylor1
1Department of Psychology, Swarthmore College.
Summary
Numerosity aftereffects result from both size and density adaptation, not just density alone. This suggests size and density are key precursors to perceiving number visually.
Area of Science:
- Visual Perception
- Psychophysics
- Cognitive Neuroscience
Background:
- Understanding visual numerosity perception is crucial for cognitive science.
- Previous research debated whether density adaptation fully explains numerosity aftereffects.
- This study directly tests density-based versus number-based explanations of numerosity aftereffects.
Purpose of the Study:
- To dissociate density-based and number-based explanations of visual numerosity aftereffects.
- To investigate the roles of density and size adaptation in perceived numerosity.
- To determine if density adaptation alone accounts for numerosity aftereffects.
Main Methods:
- A preregistered psychophysical experiment with 60 participants.
- Participants were adapted to high- or low-density stimuli of varying sizes.
- Perceived density, numerosity, and size were assessed using comparison stimuli.
Main Results:
- Numerosity aftereffects were explained by a combination of size and density adaptation.
- Density aftereffects depended solely on adapter density, not size or number.
- Numerosity aftereffects correlated with both size and density aftereffects.
Conclusions:
- Density and patch size are primary perceptual precursors to visual numerosity.
- Numerosity perception likely occurs at a later stage of visual processing.
- Density adaptation alone does not fully explain numerosity aftereffects.
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