Foveated metamers of the early visual system.

Humans' ability to discriminate spatial patterns in the visual periphery is matched by models at a critical scaling that is approximately one-fourth for luminance compared to spectral energy features.

• Why it matters: Understanding how visual discrimination declines with eccentricity helps clarify the limitations of peripheral vision and informs models of visual processing, addressing gaps in how feature representations vary across the visual field.
• What they did: The study used perceptual experiments with large synthetic stimuli, comparing human and model discrimination abilities to determine the maximum pooling window size (critical scaling) for luminance and spectral energy features, with stimuli subtending 53.6 by 42.2° of visual angle.
• The result: Critical scaling differs significantly between features and conditions, being smaller for luminance than spectral energy, and is influenced by image statistics, comparison type, and synthesis initialization, suggesting alignment issues between models and human perception.