Effects of flanker size and flanker eccentricity on the spatial integration of orthographic information

Abstract

We investigated the impact of flanker size and horizontal flanker eccentricity in the reading version of the flankers task. Critical targets and the corresponding flankers were words that could either be the same or different. Target size did not change, and flankers could either be the same size as targets or larger. Flankers could be located close to targets (normal spacing – close flankers) or separated from targets by seven spaces (distant flankers). Results revealed significant effects of flanker relatedness (same word as the target or a different word) that interacted with both flanker size and flanker eccentricity in the analysis of response times. The three-way interaction was not significant. The only significant effect in the analysis of error rates was that of flanker relatedness. We replicated prior findings showing that increasing flanker eccentricity diminishes the effect of flanker relatedness, and we further demonstrated that increasing flanker size increases the magnitude of flanker effects. Crucially, an increase in flanker size was not found to compensate for the negative impact of an increase in flanker eccentricity on effects of flanker relatedness. These results suggest that eccentricity is one key visual factor influencing the spatial integration of orthographic information, and that the impact of eccentricity overrides the impact of flanker size. This provides support for the hypothesized scale-invariant gaze-centered processing of letter identities during the initial phase of orthographic processing.