" Detecting distortions of peripherally presented letter stimuli under crowded conditions": Correction.

Abstract

Reports an error in" Detecting distortions of peripherally presented letter stimuli under crowded conditions" by Thomas SA Wallis, Saskia Tobias, Matthias Bethge and Felix A. Wichmann (Attention, Perception, & Psychophysics, 2017 [Apr], Vol 79 [3], 850-862). In the original article, the authors discovered an error in the implementation of the function used to generate radial frequency (RF) distortions. Specifically, the phase offset (φ in Eq. 3 of Wilkinson, Wilson, & Habak, 1998) was specified incorrectly. Instead of causing a" rotation" of the RF pattern, the phase offset instead altered both the angular and radial components of the distortion, causing’swirls’ that depended on the phase (see Fig. 1A). This means that the magnitude of the stimulus distortions depended on an interaction between the (randomized per stimulus) phase of the distortion and the shape of the letter. The authors corrected this bug and generated …