Opposing effects of selectivity and invariance in peripheral vision

Sensory processing necessitates discarding some information in service of preserving and reformatting more behaviorally relevant information. Sensory neurons seem to achieve this by responding selectively to particular combinations of features in their inputs, while averaging over or ignoring irrelevant combinations. Here, we expose the perceptual implications of this tradeoff between selectivity and invariance, using stimuli and tasks that explicitly reveal their opposing effects on discrimination performance. We generate texture stimuli with statistics derived from natural photographs, and ask observers to perform two different tasks: Discrimination between images drawn from families with different statistics, and discrimination between image samples with identical statistics. For both tasks, the performance of an ideal observer improves with stimulus size. In contrast, humans become better at family discrimination but worse at sample discrimination. We demonstrate through simulations that these behaviors arise naturally in an observer model that relies on a common set of physiologically plausible local statistical measurements for both tasks. Visual processing necessitates both extracting and discarding information. Here, the authors use a specialized set of stimuli and two complementary discrimination tasks to demonstrate the opposing perceptual implications of these two aspects of information processing.

Automated summary

The study demonstrates the opposing perceptual implications of the tradeoff between selectivity and invariance in sensory processing through specialized stimuli and two complementary discrimination tasks. The results show that ideal observers improve discrimination performance with stimulus size, while humans show improved family discrimination but worsened sample discrimination.