Pooling of continuous features provides a unifying account of crowding.

Ruth Rosenholtz,Shaiyan Keshvari

doi:10.1167/16.3.39

Abstract

Visual crowding refers to phenomena in which the perception of a peripheral target is strongly affected by nearby flankers. Observers often report seeing the stimuli as “jumbled up,” or otherwise confuse the target with the flankers. Theories of visual crowding contend over which aspect of the stimulus gets confused in peripheral vision. Attempts to test these theories have led to seemingly conflicting results, with some experiments suggesting that the mechanism underlying crowding operates on unbound features like color or orientation (Parkes, Lund, Angelucci, Solomon, & Morgan, 2001), while others suggest it “jumbles up” more complex features, or even objects like letters (Korte, 1923). Many of these theories operate on discrete features of the display items, such as the orientation of each line or the identity of each item. By contrast, here we examine the predictions of the Texture Tiling Model, which operates on continuous feature measurements (Balas, Nakano, & Rosenholtz, 2009). We show that the main effects of three studies from the crowding literature are consistent with the predictions of Texture Tiling Model. This suggests that many of the stimulus-specific curiosities surrounding crowding are the inherent result of the informativeness of a rich set of image statistics for the particular tasks.

Highlights

Peripheral vision refers to vision outside of the center of gaze.1 Peripheral vision is where you are not looking
We have shown here that three reasonably different crowding phenomena can be captured by this one model
Freeman et al (2012) found that when viewing letter arrays in the periphery, performance cannot be described by independent position and identity confusion; a more complex mechanism is required to account for crowding

Summary

Introduction

Peripheral vision refers to vision outside of the center of gaze (i.e., outside the central 18– 28 of visual angle known as the fovea). Peripheral vision is where you are not looking (i.e., not pointing your eyes). Peripheral vision is where you are not looking (i.e., not pointing your eyes) Despite it being markedly worse than central vision, peripheral vision is a key player in many natural tasks, including gaze guidance, object recognition, scene perception, and navigation (Strasburger, Rentschler, & Juttner, 2011; Whitney & Levi, 2011). Peripheral vision has limited acuity and color perception compared with central vision (Anstis, 1998; Strasburger et al, 2011). Whereas these deficits are well studied and significant, they only explain a small fraction of the difficulty viewers have when performing peripheral tasks. The crucial limit to peripheral processing is not lack of acuity, but rather visual crowding

Methods

Results

Conclusion