Examining the locus of the attentional attraction effect.

Our spatial perception is not always veridical. Indeed, systematic distortions in localization have been found to result from orienting of attention. Distorted localization is inferred from tasks wherein the subject reports the location of centrally presented parallel (vernier) line stimuli. Particularly, prior to the presentation of the lines, a shift of attention toward peripheral cues produces a mislocalization of the line stimuli away from the cues (termed the attentional repulsion effect [ARE]). However, if the shift of attention is induced after target presentation, by reversing the order of stimulus presentation, a substantial mislocalization toward the cues (attentional attraction effect [AAE]) is found. The purpose of this study was to identify whether the AAE arises from the modulation in the same processes as the ARE. While an interocular presentation of cues to one eye and vernier lines to the other was previously shown to eliminate the ARE, the AAE persists across both the interocular and monocular conditions (both the cues and vernier lines are presented to the same eye). Considering Ono and Watanabe's (2011) suggestion that memory traces may be involved in generating the AAE, this prospect was examined by having participants delay their response for a short (100 ms) or long (1,000 ms) period of time. The magnitude of AAE was larger with a longer delay, consistent with the involvement of visual memory. Next, to directly examine the role of spatial working memory, the attentional attraction task was embedded within either a spatial memory task (remembering the locations of one or three squares) or a color memory task (remembering the color of one or three squares). Only high spatial memory load reduced the magnitude of AAE. Our results suggest the AAE relies on changes to different visual processes than does the ARE and involves spatial working memory.